Protecting the Nation's Groundwater from

Contamination—Vol. I

October 1984

NTIS order #PB85-154201
Recommended Citation:

Protecting the Nation Groundwater From Contamination (Washington, DC: U.S. Congress, Office of Technology Assessment, OTA-O-233, October 1984).

Library of Congress Catalog Card Number 84-601126

For sale by the Superintendent of Documents

U.S. Government Printing Office, Washington, D.C. 20402
Foreword

Contamination of groundwater is the focus of public attention nationwide—it is being detected with increasing frequency, it has been detected in every State and often near

heavily populated areas, and it is linked to adverse health, economic, environmental, and

social impacts. At the same time, groundwater is being increasingly relied on for many

types of uses and currently supplies the Nation with one-half of its drinking water. The

sense of public urgency is reflected in the hearings and debates of the 98th Congress to

reauthorize major environmental laws including the Resource Conservation and Recovery

Act, the Safe Drinking Water Act, the Clean Water Act, and the Comprehensive Environmental Response, Compensation, and Liability Act ( "Superfund" ).

The objective of the OTA study, as requested by the Senate Committee on Environment and Public Works, is to assess the current status of the Nation’s knowledge about

and experience in dealing with groundwater contamination problems. Overall, the study

shows that much information is available about sources of contamination, impacts, and

technologies to guide national policy. In particular, the analysis indicates that, despite the

establishment and expansion of numerous Federal and State programs in recent years,

these efforts have a narrow focus from a groundwater perspective and, consequently, are

limited in their ability to protect groundwater quality.

The study itself focuses on existing contamination problems because of the absence

of a coherent technical foundation for understanding—i.e., integrating, analyzing, and

interpreting —information about the problems caused by groundwater contamination from

a national policy perspective. At the same time, OTA recognized that the prevention of

future contamination would also need to be explicitly considered in order to develop a

policy framework for comprehensive resource protection; for example, as experience with

hazardous wastes has shown, the cost to clean up contamination can be enormously greater

than the cost to prevent contamination. Thus, the structure of the study evolved around

the concept of protecting groundwater quality —comprised of activities to detect, correct,

and prevent groundwater contamination—even though the details focus on the detection

and correction of existing problems.

Many individual topics related to groundwater contamination, such as prevention

alternatives, the effects of specific sources on groundwater contamination, and the effectiveness of specific laws and programs have been explored in greater detail in other OTA

studies. Interested readers are referred to, among others, Assessment of Technologies for

Determining Cancer Risks From the Environment (June 1981), Use of Models for Water

Resources Management, Planning, and Policy (August 1982), Technologies and Management Strategies for Hazardous Waste Control (March 1983), The Information Content of Premanufacture Notices—A Background Paper (April 1983), Water-Related Technologies for Sustainable Agriculture in U.S. Arid and Semiarid Lands (October 1983),

Managing Commercial High-Level Radioactive Waste (in press), Cleanup of Uncontrolled

Hazardous Waste Sites Under Superfund (in progress), and Hazardous Materials Transportation: Technology Issues (in progress).

The viewpoints of the private sector, environmental groups, academia, the technical

community, and public interest organizations were sought in conducting the study. In

Ill
addition, over two dozen Federal agencies and offices were contacted for the analysis of

Federal laws and programs, and each of the States responded to the OTA State survey.

OTA thanks the numerous people—advisory panel members, reviewers, advisors, and

consultants— who gave so generously of their time and expertise in support of the study.

As with all OTA studies, the content of the report is the sole responsibility of OTA.

Director
OTA Project Staff— Protecting the Nation’s Groundwater From Contamination

John Andelin,

Science, Information,

Assistant Director, OTA

and Natural Resources Division

Robert W. Niblock, Oceans and Environment Program Manager

Project Staff

Paula J. Stone, Project Director

Joan Ham Howard Levenson Francine Rudoff

Administrative Staff

Kathleen A. Beil Jacquelynne R. Mulder Kay Senn

Contractors

Woodward-Clyde Consultants, Inc., Walnut Creek, CA

Environ Corp., Washington, DC

The University of Oklahoma, Norman OK

GeoTrans, Inc., Herndon, VA

Peter N. Davis, University of Missouri-Columbia Law School, Columbia, MO

v
Protecting the Nation’s Groundwater From Contamination Advisory Panel

Thomas Maddock, III, Chairman

Professor, Department of Hydrology and Water

University of Arizona, Tucson

Harvey Banks

Consulting Engineer

Rodney DeHan

Administrator, Groundwater Program

State of Florida Department of Environmental

Regulation

Robert Harris

Professor

Center for Energy and Environmental Studies

Princeton University

Allen V. Kneese

Resources for the Future

Jay H. Lehr

Executive Director

National Well Water Association

Perry McCarty

Chairman and Professor

Department of Civil Engineering

Stanford University

James Mercer

President

GeoTrans, Inc.

David W. Miller

Resources

President

Geraghty & Miller, Inc.

Mary Lou Munts

State Representative

76th Assembly District

State of Wisconsin

Michael A. Pierle

Director, Regulatory Management

Monsanto Co.

Anthony Z. Roisman

Executive Director

Trial Lawyers for Public Justice

Lawrence Swanson

Director

Great Plains Office of Policy Studies

James T. B. Tripp

Environmental Defense Fund

NOTE: OTA appreciates and is grateful for the valuable assistance and thoughtful critiques provided by the advisory panel members. The

views expressed in this OTA report, however, are the sole responsibility of the Office of Technology Assessment.

vi
Contents

chapter Page

1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

Protecting the Nation's Groundwater From Contamination: Findings . . . . . . . 5

Groundwater- Contamination and Its Impacts . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Federal Institutional Framework To Protect Groundwater

From Contamination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63

State Institutional Framework To Protect Groundwater

From Contamination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89

Hydrogeologic Investigations of Groundwater Contamination . . . . . . . . . . . . . . 111

Federal Efforts To Detect Groundwater Contamination . . . . . . . . . . . . . . . . . . . 145

State Efforts To Detect Groundwater Contamination . . . . . . . . . . . . . . . . . . . . . 165

The Correction of Groundwater Contamination: Technologies and

Other Alternatives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 177

Federal Efforts To Correct Groundwater Contamination . . . . . . . . . . . . . . . . . . 197

State Efforts To Correct Groundwater Contamination . . . . . . . . . . . . . . . . . . . . 205

Federal Efforts To Correct Groundwater Contamination . . . . . . . . . . . . . . . . . . 215

Overview of the States and Prevention . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 235

Index , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 243

Volume II of this report contains the following appendixes:

A. Groundwater Contamination and Its Impacts

B. Federal Institutional Framework To Protect Groundwater

C. State Institutional Framework To Protect Groundwater

D. Hydrogeologic Investigations of Groundwater Contamination

E. Federal Efforts To Detect Groundwater Contamination

F. Corrective Action: Technologies and Other Activities

G. Federal Efforts To Correct Groundwater Contamination

H. Federal Efforts To Prevent Groundwater Contamination

vii
Report Summary

and Findings
Chapter 1

Protecting the Nation’s Groundwater

From Contamination: Findings
Contents

Page

Chapter Overview . . . . . . . . . . . . . . . . . . . . ...............................:.. 5

Federal and State Approach to Groundwater Protection . . . . . . . . . . . . . . . . . . . . . . . . 6

Detection Programs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Corrective Action Programs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Prevention Programs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Technical and Non-Technical Constraints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

National Policy Implications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Funding. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Technical Assistance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Research and Development . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Chapter 1

Protecting the Nation’s Groundwater

From Contamination: Findings

—

CHAPTER OVERVIEW

Contamination of groundwater—by organic and

inorganic chemicals, radionuclides, and/or microorganisms—has occurred in every State and is

being detected with increasing frequency. For a

long time, the land surface and subsurface were

considered safe and convenient depositories for

many of society’s wastes and non-waste products.

Only recently has the limited capacity of natural

soil processes to change contaminants into harmless

substances, before they reach groundwater, become

widely recognized.

Detailed quantitative estimates of the nationwide

extent and effects of groundwater contamination

are not now, and probably never will be, available.

The time, costs, and technical requirements to develop nationwide estimates would be prohibitive.

In addition, information necessary for predicting

future contamination problems—about future uses

of groundwater, potential sources, and types of

contaminants—cannot be known with certainty.

Contaminants found in groundwater—particularly organic chemicals— are associated with adverse

health, social, environmental, and economic impacts. Although only a small portion of the Nation’s

total groundwater resource is thought to be contaminated, the potential effects of this contamination are

significant and warrant national attention.

Public health concerns arise because some contaminants are individually linked to cancers, liver

and kidney damage, and damage to the central

nervous system. They also arise because information is not available about the health impacts of

many other individual contaminants, or of mixtures

of contaminants as typically found in groundwater.

Uncertainties about human health impacts are

likely to persist because impacts are difficult to

study; for example, impacts may not be observable

until long after exposure.

Social impacts are often related to anxiety and

fear about exposure to contaminants. Exposure can

occur unknowingly because even if groundwater

is contaminated, it may be odorless, colorless, and

tasteless. Exposure can also occur over many years

and in many ways—by drinking, eating, bathing,

and breathing.

Environmental impacts include the quality degradation of not only soil, but also air and surface

water because of interrelationships among environmental media (e. g., groundwater can provide baseflow to streams). Vegetation, fish, and wildlife can

be affected adversely.

The economic costs of detecting, correcting, and

preventing groundwater contamination at even a

single site are high; for example, corrective action

can be tens of millions of dollars or more. Economic

losses that occur from impaired groundwater quality

include decreases in agricultural and industrial productivity, lowered property values, the costs for repair or replacement of damaged equipment and

materials, and the costs of developing alternative

water supplies,

Adverse impacts from groundwater contamination are likely to increase. Contaminated groundwater is often located near industrialized, heavily

populated areas, which increases the likelihood of

human exposure. Groundwater is also increasingly

relied on as a source of water for many uses;

withdrawals for all uses increased from about 35

billion gallons per day in 1950 to almost 90 billion

gallons per day in 1980. Groundwater is now a

source of drinking water for approximately one-half

the Nation’s population. It also fills about 40 percent of the Nation’s irrigation requirements, about

80 percent of rural requirements both in the home

and for livestock, and about 25 percent of selfsupplied industrial purposes (other than hydroelectric power).

5
6 ● protecting the Nation’s Groundwater from Contamination

Current information about the Nation’s groundwater contamination problems may not describe the

actual situation as much as it reflects the way in

which investigations are conducted—which contaminants have been looked for, where they have

been looked for, and where they have been found.

Because substances found as contaminants in groundwater are used throughout society, more widespread

detection of contamination can be expected as efforts increase to monitor known problems, locate

as yet undetected problems, and monitor potential

problems. Known sources of contamination include

not only the commonly recognized point sources

associated with hazardous wastes (as defined by

Federal statutes) but also non-point sources and

sources associated with non-hazardous wastes and

non-waste products.

Examples that reflect the diversity of known

sources of contamination include: injection wells

and septic tanks, which are designed to discharge

potential contaminants into the ground; storage

tanks and landfills, which are designed to store,

treat, and/or dispose of potential contaminants;

pipelines and transfer operations, which transport

potential contaminants; agricultural practices,

which include pesticide and fertilizer applications;

production wells, which provide a conduit for potential contaminants to enter groundwater; and saltwater intrusion, which can be induced or worsened

by human activities.

Groundwater contamination problems will continue, and probably increase, as long as there are

sources, contaminants, and users not being addressed. Despite the paucity of quantitative details,

sufficient information is available about the nature

of groundwater contamination to justify national

action to protect groundwater quality—described in

this study as involving choices among activities to

detect, correct, and prevent contamination—in order to minimize associated adverse impacts. Policy

options generally relate to the development and implementation of Federal and State protection programs and include a broadening of programs to those

sources, contaminants, and users not now covered

and the provision of adequate and sustained Federal

support to the States. Unfortunately, the costs and

technical uncertainties associated with detection and

correction activities effectively preclude the investigation and correction of all known and/or suspected

contamination problems. Therefore, prevention is

central to any long-term approach to groundwater

quality protection. In general, selection among

detection, correction, and prevention activities—

given limited funds and technical capabilities—will

depend on policy decisions regarding which and to

what extent groundwater resources will be protected.

FEDERAL AND STATE APPROACH TO

GROUNDWATER PROTECTION

Numerous Federal and State programs for protecting groundwater quality-for detecting, correcting, and preventing contamination-have been

established and expanded in recent years. These

efforts have made a significant contribution to the

protection of groundwater. For example, sources

of contamination have been identified, inventories

of selected sources have been conducted, numerous incidents have been documented, and scientific advances have been made in understanding

groundwater flow.

At the Federal level, at least 16 statutes authorize

programs relevant to groundwater protection, and

more than two dozen agencies and offices are involved in groundwater-related activities. All 50

States are concerned about contamination and have

programs, at varying stages of development, to protect groundwater. As many as seven agencies with

groundwater responsibilities have been identified

in a single State.

Despite growing Federal and State efforts, programs are still limited in their ability to protect

against contamination. For example, there is no explicit national legislative mandate to protect groundwater quality; and although the groundwater protection strategy of the U.S. Environmental Protection

Agency acknowledges the need for comprehensive

resource management, the details of the strategy
Ch. 1—Protecting the Nation’s Groundwater From Contamination: Findings ● 7

do not fully provide for it. Most authorized programs are in their early stages, and some are at least

10 years from being fully in place. Groundwater

quality-related programs among, and within, institutions are often not coordinated, nor are they

coordinated with programs for groundwater quantity or surface water even though groundwater and

surface water quality and quantity are interconnected.

From a groundwater protection viewpoint, existing Federal and State programs also generally

have a narrow focus with respect to sources, contaminants, and users. Essentially, the programs are

concerned with managing selected sources of contamination, selected contaminants, and the users

of public drinking water supplies.

Narrow Focus on Sources. —Federal and State

programs generally focus on managing only selected

point sources of contamination, particularly point

sources associated with hazardous wastes. The programs vary in their approaches to protection of

groundwater quality and generally do not take into

account the potential of the sources to contribute to

groundwater contamination. Further, the non-hazardous waste, non-waste, and non-point sources that

are known to contaminate groundwater are usually

not covered.

Narrow Focus on Contaminants. —This study

has documented the detection of over 200 substances—both natural and synthetic—in groundwater. Yet the Federal Government has established

only 22 mandatory water quality standards, 18 of

which are for specific chemicals. These Federal

standards, developed under the National Interim

Primary Drinking Water Regulations of the Safe

Drinking Water Act, are inadequate, as substantiated

by State responses to the OTA State survey. As a result, many States have set their own standards for

drinking water and groundwater quality; both the

types of contaminants addressed and the stringency

of standards vary from State to State.

Narrow Focus on Users. —Federal and State programs are directed primarily at the protection of

public drinking water supplies. Yet as much as 20

percent of the Nation’s population may rely on private wells for drinking water. The extent to which

people relying on private wells are being exposed to

groundwater contaminants is unknown, and data are

generally not being collected to find out. Data are

also unavailable about the impacts of groundwater

contamination on non-drinking water uses.

As a result of the narrow focus of Federal and

State programs with respect to groundwater protection in terms of sources, contaminants, and

Photo credits: State of Florida Department of Environmental Regulation (left) and Office of Technology Assessment (right)

Sources of potential groundwater contamination are diverse and include the most commonly addressed point sources

associated with hazardous wastes as well as sources associated with non-hazardous wastes (e.g., open dumps, which

are usually point in nature and may also contain hazardous wastes) and non-wastes (e.g., product pipelines,

which are non-point).
8 ● Protecting the Nation’s Groundwater From Contamination

users, related activities to protect against contamination are also narrow in focus. Examples are described below.

Detection Programs

The focus of both inventorying and monitoring

efforts is on selected point sources of contamination, primarily on sources of hazardous wastes. Federal inventories of specific sources are limited to

surface water impoundments under the Safe Drinking Water Act and to hazardous waste sites and

open dumps under the Resource Conservation and

Recovery Act. State inventories are directed primarily at sources designed to store, treat, and/or

dispose of wastes (e. g., landfills) and at sources designed to discharge potential contaminants into the

subsurface (e. g., injection wells). In general, only

recently has groundwater monitoring begun to include organic chemicals and trace metals. Routine

monitoring is required only for public drinking

water supplies, as opposed to private drinking

water supplies and supplies for non-drinking water

purposes.

Corrective Action Programs

Few corrective actions have been undertaken to

date relative to the number of sites identified as requiring such action. For example, although federally funded corrective actions authorized by the

Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA, also known

as “Superfund”) could potentially address a broad

range of sources and contaminants, actions thus far

have been restricted to primarily hazardous waste

sites; in addition, such corrective actions have generally not involved the cleanup of contaminated

groundwater. Overall, the provisions of Federal programs for corrective action vary. Two programs

establish standards for cleanup (the Resource Conservation and Recovery Act and the Uranium Mill

Tailings Radiation Control Act); other programs

(e. g., CERCLA) establish cleanup standards on a

case-by-case basis.

State corrective action programs are similarly at

an early stage of development. The greatest number

of State programs relate to spills and accidents and

to leaks from storage; other activities tend to be associated with point sources that are designed either to

retain (e. g., in landfills) or to discharge (e. g., via

injection wells) potential contaminants into the subsurface. Many State corrective actions result from

complaints rather than systematic efforts to identify

contaminated sites.

Prevention Programs

A limited number of potential sources are addressed in Federal and State programs to prevent

groundwater contamination. The programs focus

primarily on sources associated with hazardous

wastes and other toxic materials. Implementation

and enforcement of most program requirements are

still in their early stages. Differences among programs have little relationship to the potential for

different sources to cause contamination. Current

approaches to preventing contamination include

provisions for the design, operation, siting, restricted use, and closing of sources. The approaches

may be either mandatory or voluntary. Additional

approaches to the prevention of groundwater contamination from specific sources include use of

alternatives to the contaminating activity (e. g., to

land disposal), process or product changes for reduction of waste hazard levels and volumes, and

waste recycling and recovery.

A focus on sources is one approach to prevent

contamination; other types of approaches have not

been widely applied to groundwater. For example,

few efforts have been made to control activities located in recharge areas (i. e., portions of a drainage basin that replenish an aquifer). Approaches

that are not source-specific are most suitable when

there is no single identifiable source or when high

volumes of groundwater or large areas are involved

(e. g., non- point sources or a clustering of point

sources). The Federal Government does provide

some support for the protection of selected recharge

areas through the Sole Source Aquifer Program

under the Safe Drinking Water Act; selected recharge

areas are also being protected by some States and

local governments through land use controls and

land acquisition.

Another approach to prevent groundwater contamination is through restrictions on the manufacture or generation, distribution, and use of the

contaminating substances themselves. This approach recognizes the fact that any one substance
Ch. 1—Protecting the Nation’s Groundwater From Contamination: Findings ● 9

can be released into groundwater from many dif- posal. Although both the Toxic Substances Conferent sources. To illustrate, pesticides may be trol Act and the Federal Insecticide, Fungicide, and

introduced from non-point sources such as land ap- Rodenticide Act authorize regulation of potential

plication, non-waste sources such as storage tanks, groundwater contaminants, application of associhazardous waste sources such as landfills, and non- ated programs to groundwater has been limited.

hazardous waste sources such as residential disTECHNICAL AND NON-TECHNICAL CONSTRAINTS

The effectiveness of Federal and State programs

to protect groundwater from contamination has

been limited not only by their narrow focus but also

by technical and non-technical factors.

Underlying all groundwater protection activities

is the hydrogeologic investigation which is used,

for example, to detect existing problems, monitor

the performance of corrective actions, and monitor the effectiveness of preventive activities. In general, the technologies for obtaining hydrogeologic

information are available. Nevertheless, there will

always be some degree of uncertainty about contamination because of inherent difficulties in dealing with a phenomenon that is inaccessible to direct observation. Many advances have been made

to improve the reliability of results (i. e., to reduce

uncertainty), but they often increase the costs and

time required to conduct the investigation.

There are major constraints on hydrogeologic investigations in some situations. For example, the

technology for conducting reliable investigations in

certain geologic environments such as fractured

rock, which occurs throughout the United States,

is lacking. Investigations can also be very costly and

time-consuming depending on site conditions and

the level of detail required by the investigation objectives (e. g., investigations just to define a contamination problem could cost anywhere from

$25,000 to $500,000 and take many months to complete). In addition, the reliability of a hydrogeologic

investigation depends on highly skilled personnel

because investigations must be tailored to the sitespecific nature of any groundwater contamination

problem. Adequately trained personnel are generally in short supply.

Many of the constraints associated with hydrogeologic investigations—costs, time, inadequate

Photo credit: U.S. Environmental Protection Agency

In general, techniques for conducting hydrogeologic

investigations are available for most environments.

Here a drilling rig provides access to undisturbed,

uncontaminated samples of a deep aquifer; a hollowstem auger holds the drilling hole open while a

sampling tube is lowered inside and pushed

into undisturbed aquifer material.

supply of trained personnel, and technical uncertainties—also apply to detection, correction, and

prevention activities. The importance of the constraints to these activities varies, however, and additional constraints also become relevant.
—

10 ● Protecting the Nation’s Groundwater From Contamination

Detection activities are primarily constrained by

the high costs of monitoring. For example, the annual collection and analysis of groundwater quality

samples from the 12-14 million private wells in the

United States could cost $7 billion or more depending on the techniques used; and such a sampling

program would still provide only a snapshot of data,

at discrete places and for one point in time, that

conveys little information about the sources of any

existing contamination or the potential for further

or future contamination. One institutional constraint on some States is their lack of authority to

obtain data about particular sources of contamination.

Techniques for analyzing groundwater quality

samples are biased in terms of which of the contaminants present they detect, and some contaminants cannot be readily measured at low but potentially harmful levels using routinely available

methods. Water quality data can also be difficult

to analyze and interpret, especially if trace levels

or mixtures of contaminants are present or if contaminants have changed chemically and biologically

into substances different than those expected.

Major constraints on alternatives for corrective

action include: uncertainty about the effectiveness

of various techniques to improve groundwater

quality; the dependence of technology performance

on the amounts of both money and time available;

the high costs of taking corrective action of any sort;

the need for suitably trained professionals to design and implement measures appropriate for sitespecific conditions; and the lack of experience, especially with the large areas or large volumes of contaminated groundwater that are typical of non-point

sources. The nature of the contaminants is another

constraint; for example, treatment techniques can

be costly depending on the contaminants present,

and their performance is uncertain when there is

a complex mixture of contaminants and/or concentrations change rapidly. Based on experience-todate, correction alternatives-containment, withdrawal, treatment, in-situ rehabilitation, and management options—appear to be selected according

to how rapidly they can be implemented, how

rapidly they become effective, the extent to which

the uncertainties inherent in their performance can

 

be

to

Photo credit: U.S. Environmental Protection Agency

Protective clothing is worn to prevent exposure to

contaminants while undertaking corrective measures.

reduced, and whether there is clear authority

implement the selected strategy.

Institutional constraints on corrective actions

relate to ease of access to the site, availability of

alternatives for disposal of any contaminants withdrawn or excavated, and ability to implement some

correction activities (e. g., withdrawal via pumping) given established water rights. Corrective action can also have environmental side-effects. For

example, the management option of closing wells

results in the continued presence of and potential

for further migration of contaminants, and excavation may transfer contaminants to another site or

other environmental media (e. g., surface water and

air).

Major constraints on prevention efforts include

the lack of funds to implement existing programs,

uncertainty about the technical adequacy of available methods and ongoing efforts, and incomplete

understanding about the relationship between land

use and groundwater quality. Some techniques used

to prevent contamination are the same as those used

for correction (e. g., containment measures such as

liners), so that the same uncertainties about performance are pertinent.
Ch. 1—Protecting the Nation’s Groundwater From Contamination: Findings ● 1 1

NATIONAL POLICY IMPLICATIONS

National policy options generally relate to the development and implementation of Federal and State

groundwater quality protection programs.

The existing Federal statutory framework appears to have the potential to protect the Nation’s

groundwater from further contamination. However, the realization of this potential will depend on

broadening the coverage of authorized programs to

those sources, contaminants, and users not presently

included and on effectively implementing programs.

Many approaches for broadening and implementing programs are possible, such as mandatory requirements, voluntary procedures, and/or incentives and disincentives. Effective implementation

will also require the coordination of activities among

and within agencies (e. g., health departments, State

geological surveys, and departments of environmental protection) for both groundwater and surface water quality and quantity. Ultimately, groundwater quality protection will also depend on political

judgments about both the appropriate role of the

Federal Government and the importance of all

States making comparable progress in their abilities

to detect, correct, and/or prevent groundwater contamination.

Fundamental to the development of any national

policy related to the protection of groundwater from

contamination is recognition of the site-specific

nature of the problems. Efforts to detect, correct,

and prevent contamination must be tailored to the

full range of conditions found at any site, including sources, contaminants, and users. National policy must be flexible in its ability to respond to and

accommodate different groundwater quality problems characterized by varying site conditions. For

example, the choice of appropriate monitoring

parameters, locations, and frequencies cannot be

rigidly specified apart from site conditions; however, the factors that need to be considered in making this choice could be specified. A major function

of the Federal Government would be to provide adequate and sustained support to the States for detecting, correcting, and preventing groundwater contamination. The principal areas for Federal support

to the States that would be the most helpful in achieving groundwater quality protection are funding,

technical assistance, and research and development.

The need for flexibility in national policy is

underscored by the vast differences among State

approaches to protecting groundwater. States vary

in their perception about their contamination problems, priorities among sources and users, capabilities, stages of program development and implementation, and institutional arrangements. Land

use considerations, essential for preventing contamination from non-point sources or from clusters

of point sources, have traditionally been addressed

at the State and local levels.

Current Federal laws and programs have generally helped the States with their groundwater contamination problems. However, based on responses

to the OTA State survey, the level of Federal support to the States is not adequate; nor is it directed

at all of the States’ problems. In some cases, current Federal laws and programs have created problems: surface water quality problems have been

reduced at the expense of groundwater quality because Federal programs fail to recognize the interrelationships among environmental media; Federal

programs fail to accommodate variations in State

conditions; and the lack of an explicit national

legislative goal to protect groundwater quality has

led to uncoordinated Federal programs and has

handicapped the States in obtaining authority to

address certain problems.

Funding

Currently no Federal program has earmarked

funds specifically for the protection of groundwater

quality. In addition, funding for programs that have

supported groundwater-related activities has been

reduced or eliminated (e. g., funding under Section

208 of the Clean Water Act, for State solid waste

programs under Subtitle D of the Resource Conservation and Recovery Act, and for the Rural

Abandoned Mine Program under the Surface Mining Control and Reclamation Act). As a result,
12 ● protecting the Nation’s Groundwater From Contamination

groundwater and other water quality programs are

competing for limited State grants (e. g., under Sections 106 and 205(j) of the Clean Water Act). Because of the high costs associated with groundwater

protection, Federal funding assistance is desired by

the States for both the development and implementation of State initiatives.

Technical Assistance

Technical assistance to the States can include

training programs, the development of criteria

and/or guidelines, and information exchange.

Qualified personnel are essential for protection

activities because activities need to be tailored to

site conditions. The supply of qualified technical

personnel appears to be limited and to be an important constraint on the Nation’s ability to protect

groundwater quality. Federal support for training

and education is required for a rapid increase in

the Nation’s technical capabilities. The States have

been assisted by the Cooperative Program of the

U.S. Geological Survey, and they would like to see

it and other technical assistance programs continued. Establishment of professional certification

programs or other criteria (e. g., by the Federal

Government, the States, or professional societies)

for ensuring that personnel possess minimum technical qualifications would also help to develop—and

to provide a check in the hiring of—qualified technical manpower.

Although contamination problems require sitespecific judgments, they nevertheless have common

features that are amenable to the development of Federal criteria and/or guidelines. From a national perspective, the goal of these criteria and/or guidelines

would be to ensure that at least a minimum set of

considerations is being taken into account for protection of groundwater quality. Further, they would

also be an efficient means of providing information

required by all States in handling their groundwater

contamination problems; for example, general

guidelines could be developed for assisting the

States in setting priorities for allocating scarce

resources among alternative protection activities.

In addition to criteria and guidelines, the Federal

Government could provide direct assistance to

States in specified situations.
Ch. 1l—Protecting the Nation’s Groundwater From Contamination: Findings ● 1 3

Technical assistance could include:

● With respect to detection:

— Criteria and/or guidelines to assist the

States in conducting reliable hydrogeologic

investigations under different site conditions and in addressing, for example,

monitoring of the flow system, sampling

and analysis, and data interpretation.

— Criteria and/or guidelines for addressing

contaminants for which there are no Federal standards, including for mixtures.

Standards development for these contaminants is also needed (see Research and Development, below),

— Criteria and/or guidelines to assist the

States in setting priorities among sources

and in determining which sources they will

monitor and inventory.

● With respect to correction:

Criteria and/or guidelines to assist the

States in selecting and implementing corrective action under various conditions.

Criteria and/or guidelines for setting

cleanup standards on a site-specific basis,

incorporating such factors as the limitations and likely performance of technology and current and/or potential users.

● With respect to prevention:

— Criteria and/or guidelines for preventing

contamination from all potential contaminating sources; for a given source, performance criteria and/or guidelines for addressing its siting, design and operation

during its active life, and closure. Alternatives for reducing the wastes generated

by a source, and for waste recycling, also

need to be considered as part of preventing contaminant ion from sources.

— Criteria and/or guidelines for considering

prevention alternatives apart from those

related to specific sources, e.g., for the protection of aquifer recharge areas and for

establishing an institutional memory for

the locations of sources, contaminants, and

land uses.

Because of the complexities of groundwater contamination problems and because efforts to protect

groundwater are generally in their early stages,

there are several important opportunities for the

Photo credit; John Gilbert, EPA Environmental Response Team

Training of staff is required for dealing safely and

effectively with site-specific groundwater

contamination problems.

Federal Government to facilitate information exchange among the States. Information exchange

would not necessarily include the details of sitespecific case studies; rather, programmatic information about State approaches to protection would

assist the States in learning from the successes, and

failures, of each other.

Research and Development

Some research and development activities can

provide timely information that would support all

of the States in their groundwater protection efforts.

Key activities include:

● With respect to detection:

Research on toxicology and the adverse

health effects of contaminants that are being found in groundwater, with particular emphasis on the synergistic effects of

mixtures of contaminants.

Development of water quality standards

for substances known to occur in ground-
74 ● Projecting the Nation’s Groundwater From Contamination

water that are not now covered; these standards could be applied in State drinking

water and groundwater quality programs.

— Research on assessment of the environmental and economic impacts of contamination.

— Research on less costly techniques for

hydrogeologic investigations in general

and development of reliable techniques for

conditions that cannot now be addressed

adequately (e. g., fractured rock).

● With respect to correction:

— Research on the behavior of individual

contaminants in groundwater and, in particular, on the potential for the chemical

and biological transformation of organic

chemicals.

— Research on chemical and biological reactions in fluids that would be necessary, for

example, for the development of techniques for treating water with multiple

contaminants.

● With respect to prevention:

— Opportunities and mechanisms for preventing contamination, including ways of

reducing the generation (e. g., by process

or product changes) and disposal (e. g.,

through resource recovery and recycling)

of potential contaminants.

Ultimately, the protection of groundwater from

contamination will also depend on raising the consciousness of the public as has been done for litterIllustration credit: Sacramento County, CA

Some communities have implemented household

hazardous waste collection programs as part of their

efforts to protect groundwater quality.

ing and air and surface water pollution. All segments of society need to understand how their

activities affect groundwater quality and, in turn,

how they may be affected. Public confidence will

grow only as the Nation makes timely efforts to

detect, correct, and prevent groundwater contamination from all sources and contaminants, to protect all of the public’s interests.

Chapter 2

Groundwater Contamination

and Its Impacts
Contents

Page

Chapter Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Extent and Nature of Groundwater Contamination . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Assessing the Nationwide Extent of Groundwater (contamination . . . . . . . . . . . . . . . . . . . . 20

Substances Known to Occur in Groundwater . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

Health Impacts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

General Issues. ...... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

Adverse Impacts of Chemicals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

Potential Toxicity or Potency of Chemicals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

Interactions Among Multiple Chemicals, . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

Biological Substances . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

Radioactive Substances . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

Non-Health Impacts .......................................... . . ... . . . ... 36

Economic Impacts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

Environmental and Social Impacts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

Concentration and Frequency of Substances Found in roundwater . . . . . . . . . . . . . . 38

Concentration of Substances in Groundwater . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

Frequency of Occurrence of Substances in Groundwater . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

Concentration and Frequency Data in Relation to Governmental Standards . . . . . . . . . . . . 41

Potential But as Yet Undetected Substances in Groundwater . . . . . . . . . . . . . . . . . . . . 43

Types of Sources and Associated Substances . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

Types of Sources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

Association o! Substances Found in Groundwater With Sources . . . . . . . . . . . . . . . . . . . . . . 44

Factors lnfluencing a Source’s Potential To Contaminate Groundwater . . . . . . . . . . . 47

Release Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

Geographic Location: Pervasiveness and Regionality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49

Numbers of Sources and Amounts of Material Flowing Through or Stored in Sources . . . 51

Potential for Sources To Contribute Substances to Groundwater . . . . . . . . . . . . . . . . . 55

Modeling the Potential of Sources To Contaminate Groundwater . . . . . . . . . . . . . . . . . . . . . 55

Identifying Sources With “Significant” Potential To Contribute Substances

to Groundwater . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

Chapter 2 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58

TABLES

TabIe No. Page

1. Substances Known to Occur in Groundwater, Ranges of Detected Concentrations,

Exceeded Standards, Examples of Uses, and Quantitative Estimates of

Carcinogenic Potency and Noncarcinogenic Toxicity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

2. Examples of Economic, Environmental, and Social Impacts Resulting From

Groundwater Contamination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

3. Examples of Economic Costs Resulting From Contaminated Groundwater . . . . . . . . . . . 39

4. Potential Groundwater Contaminants Displaying Serious Adverse Health Effects . . . . . 44

5. Sources of Groundwater Contamination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

6. Sources and Classes of Associated Substances. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

7. Summary of Source Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50

8. Numbers of Sources and Amounts of Material Flowing Through or

Stored in Sources, . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52

9. “Important” Sources of Groundwater Contamination

Based on Selected Sets of Criteria . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
Chapter 2

Groundwater Contamination and Its Impacts

CHAPTER OVERVIEW

Groundwater is an increasingly important resource in the United States—it is relied on for about

50 percent of drinking water supplies; it is used to

supply water for almost 80 percent of rural domestic

and livestock needs, about 40 percent of irrigation

needs, many commercial activities, and almost 25

percent of self-supplied industrial needs (other than

thermoelectric power); it is used for stream flow

maintenance and as a barrier to salt-water intrusion; and it is both an intentional and unintentional

depository for society’s waste and non-waste products (USGS, 1983a).

The degree of reliance on groundwater varies significantly around the Nation. For example, groundwater withdrawals for public water supplies vary

from 11 percent in the Great Lakes region to 75

percent in the Rio Grande region, for rural uses

from 12 percent in the Upper Colorado to 100 percent in New England, and for irrigation from 1 percent in the Upper Colorado to over 90 percent in

the Upper Mississippi.

Contamination of the Nation’s groundwater resource has recently become an issue of widespread

public concern. This chapter analyzes current

knowledge about the nationwide extent of contamination, the substances known to occur in

groundwater and their associated impacts, and

known sources of contamination. Specific topics

addressed are:

● the extent of groundwater contamination and

difficulties in its assessment;

● substances known to occur in groundwater and

their uses;

● health impacts of contamination;

. non-health impacts of contamination (e. g.,

economic and environmental impacts);

1 Substance is defined in this study as any organic or inorganic chemical, micro-organism, radionuclide, or other material (e. g., sediments).

Whether or not a substance is a ‘ ‘contaminant’ depends on its association with adverse impacts and on other site-specific factors (e. g,,

hydrogeology).

●

●

●

●

●

concentration and frequency of compounds in

groundwater;

potential but as yet undetected substances in

groundwater;

types of sources and their associated substances;

factors influencing a source’s potential to contaminate groundwater (including estimates of

numbers of sources and amounts of material

flowing through or stored in sources); and

the potential for sources to contaminate

groundwater.

Major conclusions drawn from this information are

summarized below.

The portion of the Nation’s groundwater resources that is contaminated is believed by experts

to be small. No matter how small, this portion is

nevertheless significant because of its location near

heavily populated areas and because of the many

uses of and increasing dependence on groundwater.

The site-to-site variability of contamination, combined with the expense and time required to investigate potential contamination problems, means

that a detailed nationwide description of groundwater quality may never be attainable.

A variety of adverse impacts due to groundwater

contamination is possible—including effects on

public health, the environment, agricultural productivity (e. g., due to increased salinity in irrigation water), and on the output of industries requiring high-quality water. Public attention has focused

primarily on the potential for health effects; because

little information is available on other impacts, this

chapter focuses on potential damage to human

health.

Even if a comprehensive description of groundwater quality were available, the magnitude and

exact nature of public health effects resulting from

contamination could not be estimated with confidence. At best, evidence would involve the documentation of effects attributable to contamination,

19
20 • Protecting the Nation’s Groundwater From Contamination

with predictions regarding the magnitude and types

of future effects. This type of information is typically obtained from risk assessment analyses,

wherein data on: 1 ) the adverse effects and 2) toxicity (i. e., dosage levels at which adverse effects are

observed) of substances are linked with 3) exposure

data to identify probabilities of adverse impacts on

human health.

Data limitations preclude a risk assessment of the

magnitude of public health risks from groundwater.

Some of the data required for risk assessment analysis of groundwater contamination are available, primarily regarding known or possible hazards and

known toxicities, but much of this information is

not precise enough. Almost no data are available

on human exposure to the substances of concern.

These types of data are not likely to be obtainable

in sufficient detail in most cases because of the inherent limitations of epidemiological investigations.

For example, data would be needed—and, again,

are probably unattainable—on the amount of exposure to substances from only groundwater (e. g.,

as opposed to exposure to the same substances from

other media such as air and surface water), on the

number of people exposed to various concentrations, and on interactions among substances when

more than one substance is present.

Although the magnitude of the impacts of groundwater contamination cannot be estimated with confidence, the nature of many impacts is known.

There is also a substantial body of indirect evidence

indicating the large potential for groundwater contamination and subsequent health effects. Over 200

substances have already been detected in groundwater—substances that are used throughout society

in a multiplicity of commercial, industrial, and

household activities. For some, but not all, of these

known substances, information is available about

their adverse effects on laboratory animals and

humans, toxicity levels, and the range of concentrations found in groundwater. Many of the substances present in groundwater can cause liver and

kidney damage, damage to the central nervous system, cancers, and eye and skin irritation.

The pathways by which substances eventually enter groundwater are diverse and extremely complex—i.e., they can enter during production, handling, storage, processing, disposal, transport, and

use. One focal point along these pathways, which

Congress has started to address in recent legislation, is the sources from which contaminants enter groundwater. Sources of contamination are convenient for assessing possible detection, correction,

and prevention actions. At least 33 major sources

are known. There is a vast diversity among sources

in terms of their associated substances, release

characteristics, amounts of materials, geographic

location, and role in society.

So far, most attention given to sources has concerned waste discharges (particularly hazardous

wastes) from point sources. As shown by OTA’S

analysis, many potential sources of contamination

also are associated with both non-hazardous wastes

and non-waste products; and contaminants can enter groundwater from both point and non-point

sources. Important advances have been made in

the information base concerning sources since the

U.S. Environmental Protection Agency’s 1977 Report to Congress on waste disposal practices (EPA,

1977),

EXTENT AND NATURE OF

GROUNDWATER CONTAMINATION

Assessing the Nationwide Extent of and the Safe Drinking Water Act—groundwater

Groundwater Contamination contamination has historically received little attention at the national level. One major reason was

Although contamination of surface water has the common belief that groundwater was pristine,

long been of concern to the public and to Con- i.e., that potential contaminants percolating through

gress—as demonstrated by passage of the Federal the subsurface would adhere to the soil or be deWater Pollution Control Act (the Clean Water Act) graded by natural processes and, therefore, would
Ch. 2—Groundwater Contamination and Its Impacts ● 2 1

} Unsaturated zone

 Unconfined aquifer

 (fresh groundwater)

Confined aquifer

(fresh groundwater)

Confined aquifer

(brackish groundwater)

Credit: Geraghty & Miller, 1983

Pathways of groundwater contamination vary depending on the source. Examples of sources are shown here for each

of OTA’S six source categories (I-VI) (see the section on Types of Sources and Associated Substances, below).

not enter or greatly affect groundwater quality.

Thus the subsurface, and groundwater, had been

regarded as a safe and convenient depository for

the wastes and non-waste byproducts generated by

society.

But there is a growing consensus that the quality

of groundwater is in decline. Incidents of contamination are being reported with increasing frequency

and have now occurred in every State. Although

the activities and practices that cause contamination are varied and were often begun many years

ago, groundwater contamination recently has come

to the attention of the public, primarily in the context of threats to human health. Most of the attention has focused on sources associated with hazardous wastes (e. g., landfills, surface impoundments,

and waste piles) because of the severity of their impacts on surrounding populations and environments—groundwater has been seriously contaminated by toxic chemicals associated with these

sources in at least 34 States (CEQ 1981). However, non-hazardous wastes and non-wastes also

contribute to the contamination of groundwater.

A small amount of the Nation’s groundwater is

generally believed to be contaminated (estimates

range from about 1-2 percent). Although this portion may seem very small, it is significant because

contamination is often near heavily populated areas

and groundwater is being increasingly relied on for

a variety of uses.

The extent of groundwater contamination is also

likely to be greater than 1-2 percent. Descriptions

of groundwater quality problems often include

anecdotal or non-comparable data, making them

difficult to interpret and analyze. In addition, much

of the current information on the extent and magnitude of contamination reflects only the nature of

investigations —where and which substances have

been looked for and where they have been found.

For example, groundwater that is not used for public drinking water supplies is not always tested, and

more information is generally available about hazardous waste sources than about non-point sources

and sources with non-hazardous wastes and nonwaste products. Further, substances known to contaminate groundwater are used throughout society;

thus, more widespread detection of contamination

can be expected as efforts increase to monitor

known, as yet undetected, and potential problems.

Little is known about how much contamination is

reversible and how rapidly new sites and sources

of contamination are being created.

A complete description of contamination would

require detailed information about groundwater
“”””””””-––-- ,

Thirty-four of the 100 largest cities in the United

quality on a site-by-site basis throughout the Nation and about associated site-specific hydrogeologic

conditions (e. g., the vulnerability of groundwater

to the entrance of substances). A difficulty in assessing the extent of groundwater contamination is that

not all substances entering groundwater may have

adverse impacts. Whether the presence of substances in groundwater results in a contamination

problem depends on site-specific hydrogeology, the

potential for adverse impacts (health, economic,

environmental, and social), current and future

groundwater use patterns, the exposure of humans

to the substances, the availability of alternative

water supplies, and the feasibility of corrective

measures including management alternatives.

The lack of data about groundwater quality stems

from the technical complexity of groundwater.

Groundwater and associated problems often cannot be directly observed and are not easily measPhoto credit: State of Florida Department of Environmental Regulation

States rely completely or partially on groundwater.

ured, and the behavior of substances in groundwater is not well understood—the movement of

substances varies temporally and spatially in different hydrogeologic environments, and chemical

and biological processes can alter the nature and

subsequent behavior of substances. For these reasons, groundwater contamination problems are

highly site-specific. Given this complexity and the

costs and time that would be needed to gather data,

a complete description of groundwater quality may

never, for all practical purposes, be attainable.

Substances Known to Occur

in Groundwater

As part of the OTA study, information was

gathered that documents the presence of over 200

substances known to occur in the Nation’s groundwater. Specific substances detected in groundwater
Ch. 2—Groundwater Contamination and Its Impacts ● 2 3

thus far, and examples of major uses of these substances, are shown in table 1. These substances include about 175 organic chemicals, over 50 inorganic chemicals (metals, non-metals, and inorganic

acids), biological organisms, and radionuclides.

The presence of substances in groundwater and

an understanding of how, why, and where they are

present are directly related to their use and/or

disposition. As shown in table 1, many substances

found in groundwater are widely used by industry, agriculture, commerce, and households. Potential contaminants can thus enter groundwater

at numerous points as materials flow through society. Although most points-of-entry are associated

with particular sources, the sources themselves are

not the only places for controlling the entry of

substances to groundwater (preventive strategies are

discussed in chs. 11 and 12). However, focusing

on sources is convenient to, assess how substances

enter groundwater. The relationship between substances and specific sources is discussed below in

Types of Sources and Associated Substances.

HEALTH

General Issues

Many naturally occurring and synthetic substances can cause biological injury, disease, or death

under certain conditions of exposure. Whether injury or illness occurs depends on many factors, including properties of the substance, dosage of and

exposure to the substance, and characteristics of the

individuals exposed. Many of the diseases and effects associated with groundwater contaminants are

discussed below; however, data are insufficient for

determining the relative importance of these contaminants in causing various effects.

Relationships between health impacts and different groups of substances-organic and inorganic

chemicals (non-radioactive), micro-organisms, and

radionuclides— are not understood with the same

degree of knowledge and certainty. For example,

there is a long history of public health efforts to unDetection of substances in groundwater is biased

not only by sampling and analytical limitations (see

ch. 5) but also by the circumstances that prompted

detection and reporting. There appear to be two

major circumstances under which substances are

being detected in groundwater: 1) as the result of

planned activities (e. g., regulatory compliance,

analysis and data management activities, routine

monitoring, research, and liability protection); and

2) in response to apparent impacts (e. g., citizen

complaints stemming from the observable or feared

presence of substances, accidents, and aerial photography) (University of Oklahoma, 1983). The

two most frequently cited reasons for detection of

substances are regulatory compliance as a planned

activity and response to public complaints. Reliance

on public observation probably will not lead to the

detection of many substances—most substances

of concern are odorless, colorless, and

unobservable without use of special

equipment.

IMPACTS

derstand and address micro-organisms,

. . .

otherwise

analytical

albeit primarily in surface water, and many sources of data

are available. Radionuclides have been studied extensively since the 1940s, and much is now known

about their health impacts, although not often at

low concentrations. In contrast, health effects

resulting from exposure to many chemicals are not

well understood, in large part because of the relatively recent occurrence of and exposure to certain

chemicals in the environment. Health effects of

chemicals are of the greatest concern because chemicals are pervasive and persist in the environment.

Assessing risks from substances in groundwater

requires information about adverse effects, toxicity,

and exposure (extensive details on risk assessment

are available in NAS, 1983, and Environ Corp. ,

1983; a brief summary is presented in app. A. 1.);

and available data are often insufficient to conduct

such an assessment. Thus human health impair-
Table 1 .—Substances Known to Occur in Groundwater, Ranges of Detected Concentrations, Exceeded Standards, Examples of Uses, and

Quantitative Estimates of Carcinogenic Potency and Noncarcinogenic Toxicitya

Carcino- NoncarcinoContaminant Concentrationb

genie genie

StandardC Examples of usesd

potency e,f toxicititye,g

Aromatic hydrocarbons . , . . . . .

AcetanilideA!kyl benzene sulfonates

Aniline

Anthracene

Benzene

Benzidine

Benzyl alcohol

Butoxymethylbenzene

Chrysene

Creosote mixture

Diben[a.h.]anthracene

Di-butyl-p-benzoquinone

Dihydrotrimethylquinoline

4,4-Dinitrosodiphenylamine

Ethyl benzene

Fluoranthene

Fluorene

Fluorescein

Isopropyl benzene

4,4’-Methylene-bis-2-chloroaniline

(MOCA)

Methylthiobenzothiazole

Naphthalene

o-Nitroaniline

Nitrobenzene

4-Nitrophenol

n-Nitrosodiphenylamine

Phenanthrene

n-Propylbenzene

Pyrene

Styrene (vinyl benzene)

Toluene

1,2,4-Trimethylbenzene

Xylenes (m,o,p)

(parts per billion)

—

1 8

h

0.6-20,230

10

0.9-4,000

31

290

6.7-82

18-471h

48

0.1-6,400

0.07-300

Oxygenated hydrocarbons

Acetic acid

photographic chemicals, insecticides

Low

High

Low

Low

Low

Moderate

Low

Low

Low

Low

●
Table 1 .—Substances Known to Occur in Groundwater, Ranges of Detected Concentrations, Exceeded Standards, Examples of Uses, and

Quantitative Estimates of Carcinogenic Potency and Noncarcinogenic Toxicitya—continued

o

Oxygenated hydrocarbons (cent’d) (parts per billion) I Acetone 1O-3,OOO Dyestuffs, solvent, chemical manufacturing, cleaning and

drying of precision equipment

Organic synthesis, odor fixative, flavoring, pharmaceuticals

Solvent

Plastics, intermediate

Plasticizer, solvent, adhesives, insecticides, safety glass,

inks, paper coatings

Chemical manufacturing, solvent, analytical chemistry,

anesthetic, perfumes

Plastics, explosives, solvent, insecticides, perfumes

Solvent, rubber cements, paint and varnish removers

Intermediate, solvent, lubricant

Pharmaceuticals, plastics, disinfectants, solvent, dyestuffs,

insecticides, fungicides, additives to lubricants and

gasolines

Plasticizer for polyvinyl chloride and other vinyls

Solvent, lacquers, paints, varnishes, cleaning and detergent

preparations, fumigants, paint and varnish removers,

wetting agent, cosmetics

Polymers, acrylic paints, intermediate

Dyeing and finishing, chemicals, manufacture of fumigants,

insecticides, solvents, plastics, refrigerants

Chemical manufacturing, solvents, automotive antifreeze, fuels

Solvent, lacquers

Solvent, paint removers, cements and adhesives, cleaning

fluids, printing, acrylic coatings

Nal

Resins, solvent, pharmaceuticals, reagent, dyestuffs and

indicators, germicidal paints

Dyestuffs, medicine, perfumes, reagent

Chemical manufacturing, solvent, deicing agent, pharmaceuticals, perfumes, lacquers, dehydrating agent, preservatives

Solvent

Solvent

Paint and varnish thinner

Low

Low

Low

Benzophenone

Butyl acetate

n-Butyl-benzylphthalate

Di-n-butyl phthalate

I

10-38

470 ●

●

w

Diethyl ether

Diethyl phthalate

Diisopropyl ether

2,4-Dimethyl-3-hexanol

2,4-Dimethyl phenol

20-34

Di-n-octyl phthalate

1,4-Dioxane

Ethyl acrylate

Formic acid

Methanol (methyl alcohol)

Methylcyclohexanone

Methyl ethyl ketone

High

Methylphenyl acetamide

Phenols (e.g., p-Tert-butylphenol) 1O-234,OOO ●

Phthalic acid

2-Propanol

2-Propyl-1-heptanol

Tetrahydrofuran

Varsol

Hydrocarbons with specific elements

(e.g., with N, P,S,Cl,Br,l,F)

Acetyl chloride

Alachlor (Lasso)

Aldicarb (sulfoxide and sulfone;

Temik)

Aldrin

Atrazine

Benzoyl chloride

Bromacil

Bromobenzene

Dyestuffs, pharmaceuticals, organic preparations

● Herbicides

●

Insecticide, nematocide

190-1,700

38-405

Moderate

High

High

Moderate

Moderate

Moderate

● Insecticides

● Herbicides, plant growth regulator, weed control agent

Medicine, intermediate * Herbicides

Solvent, motor oils, organic synthesis

72-110

1.9-5.8
(e:g., with N,P,S,CI,B;,I,F) (cent’d) (parts per billion)

—

1.4-110

2.4-110

4-160

0.3-18,700

2.7-41

1.4-1,890

—

44

83

2.4

—

2.1-55

1-137

—

35-300

44.9

—

2.7

0.6-0.7

0.01-0.8

0.05-0.22

0.5-11.330

●

●

●

Low

Moderate

Moderate

Moderate

Moderate

Low

Moderate

Moderate

Moderate

Low

High

1,1-Dichloroethane r Low
Ch. 2—Groundwater Contamination and Its Impacts ● 2 7

c

l o )

.- .-

1 1

. -

x

l

5-

E

—%

—)

* ● ☛ ● ● ● * * ● ● 0

E-

.-0—

o

o

o

I I I I 0 I

—n

II

I-.
Hexachloroethane

Trichlomethanes (1,1,1 and 1,1,2)

1,1,2-Trichloroethylene (TCE)

(parts per billion)

6

3.8

0.5-43

4.6

7.4

4.6

—

—

8-40

—

3,400

5,–m

4

717-2,405

1-570

2

37

0.2-26,000

210-37,000

26

—

—

●

Insecticides

●

Insecticides

●

Insecticides

●

●

●

●

●

●

●

Intermediate for resins, dyestuffs, pesticides, fungicides,

pharmaceuticals

Solvent, pyrotechnics and smoke devices, explosives,

organic synthesis

N A

i

Pesticides

Insecticides

Insecticides

Fumigants, pesticides, organic synthesis

Insecticides

Insecticides

Insecticides, fungicides, bactericide, algicides, herbicides,

wood preservative

Insecticides

●

•

●

●

Flame retardant for plastics, paper, and textiles

Heat-exchange and insulating fluids in closed systems

Herbicides

Explosives

Herbicides

N A

i

Degreasers, paint removers, varnishes, lacquers, photographic film, organic synthesis, solvent, insecticides,

fumigants, weed killer

Degreasers, drycleaning, solvent, drying agent, chemical

manufacturing, heat-transfer medium, vermifuge

Insecticides

Herbicides

Solvent, dyestuffs, insecticides, lubricants, heat-transfer

medium (e.g., coolant)

Pesticides, degreasers, solvent

Degreasers, paints, drycleaning, dyestuffs, textiles, solvent,

refrigerant and heat exchange liquid, fumigant, intermediate aerospace operations

Solvent, refrigerants, fire extinguishers, intermediate

Fungicides, herbicides, defoliant

● Herbicides, defoliant

Low

Low

Moderate

Moderate

Moderate

Low

Moderate

Low

Low

Moderate

High

Moderate

High

Moderate

Moderate

Low

Moderate
Ch. 2—Groundwater Contamination and Its Impacts ● 2 9

)

● ● * ● * * ● ☛ *

I I I

t-

-0
Metals and cations (cent’d)

Chromium

Cobalt

Copper

Iron

Lead

Lithium

Magnesium

Manganese

Mercury

Molybdenum

Nickel

Palladium

Potassium

Selenium

Silver

Sodium

Thallium

Titanium

Vanadium

Zinc

Nonmetals and anions

Ammonia

Boron

Chlorides

Cyanides

Fluorides

Nitrates

Nitrites

Phosphates

Sulfates

Sulfites

(parts per million)

0.06-2,740

0.01-0.18

0.01-2.8

0.04-6.200

0.01-5.6

—

0.2-70

0.1-110

0.003-0.0”

0.4-40

0.05-0.5

—

0.5-2.4

0.6-20

9-330

3.1-211

—

—

243

0.1-240

1-900

—

1,0-49,500

1.05-14

0.1-250

1.4-433

0.4:33

0.2-32,318

—

●

●

☛

●

●

●

●

●

●

●

●

●

●

☛

●

●

●

●

●

●

●

●

●

Alloys, electroplating, electronics, automotive parts, fungicides, roofing, cable wrappings, nutrition

Fertilizers, chemical manufacturing, refrigerants, synthetic

fibers, fuels, dyestuffs

Alloys, fibers and filaments, semi-conductors, propellants

Chemical manufacturing, water purification, shrink-proofing,

flame-retardants, food processing

Polymer production (heavy duty tires), coatings, metallurgy,

pesticides

Toothpastes and other dentrifices, additive to drinking water

Fertilizers, food preservatives

Fertilizers, food preservatives

Detergents, fertilizers, food additives

Fertilizers, pesticides

High

High

Moderate

High

Low

High

High

Moderate High

Low

High

High

High

Low

High,

moderate

Moderate

High

Moderate

Pulp production and processing, food preservatives

●
Table I.—Substances Known to Occur in Groundwater, Ranges of Detected Concentrations, Exceeded Standards, Examples of Uses, and

Quantitative Estimates of Carcinogenic Potency and Noncarcinogenic Toxicitya—continued

Carcino- Noncarcino-

(parts per million)

— ●

(picocuries per

milliliter)

—

6.4

Iron 59 —

Lead 210 —

Phosphorus 32 —

Plutonium 238, 243

Radium 226 0.8-25

Radium 228 12.5

Radon 222 — ●

Ruthenium 106 —

Scandium 46 —

Strontium 90 0.817 ●

Thorium 270 —

Tritium 150-353 ●

Uranium 238 10-500 ●

Zinc 65 —

genie genie

Examples of usesd

potency e,f toxicity e,g

Gamma radiation source for certain foods

Diagnosis of blood volume, blood cell life, cardiac output, etc.

Radiation therapy, irradiation, radiographic testing, research

Medical diagnosis, therapy, leak detection, tracers (e.g., to

study efficiency of mixing pulp fibers, chemical reactions,

and thermal stability of additives to food products),

measuring film thicknesses

Medicine, tracer

N A

i

Tracer, medical treatment, industrial measurements (e.g., tire

tread wear and thickness of films and ink)

Energy source weaponry

Medical treatment, radiography

N A

i

Medicine, leak detection, radiography, flow rate measurement

Catalyst

Tracer studies, leak detection, semi-conductors

Medicine, industrial applications (e.g., measuring thicknesses,

density control)

NAi

Tracer, luminous instrument dials

Nuclear reactors

Industrial tracer (e.g., to study wear in alloys, galvanizing, body

metabolism, function of oil additives in lubricating oils)

CA
32 ● Protecting the Nation’s Groundwater From Contamination

ment is not easily linked to substances found in

groundwater. Adverse effects and toxicity are discussed below. With respect to exposure, five possible pathways of human exposure have been identified (Environ Corp., 1983):

1. direct ingestion through drinking;

2. inhalation of contaminants (e. g., during showering);

3. skin absorption from water;

4. ingestion of contaminated food; and

5. skin absorption from contaminated soil.

Except for drinking water containing known levels

of substances, there appear to be no general models available for estimating exposure through these

routes.

Adverse Impacts of Chemicals

Many of the chemicals detected in groundwater

are known or suspected to cause a variety of adverse

health effects, including depression of central nervous system functions, liver and kidney damage,

and eye and skin irritation. Some of these chemicals are known or suspected human carcinogens.

The discussion below summarizes the known adverse effects of individual chemicals found in

groundwater; the data upon which the summary

is based are shown in appendix A.2.

Much of the data reviewed below concerning the

effects of chemicals is derived from experimental

studies on laboratory animals, but some information (e. g., acute effects such as eye and skin irritation, some cancers) is based on studies of human

populations. The inference of human health effects

from animal studies is controversial and is reviewed

elsewhere (Environ Corp., 1983). However, for

many chemicals, data from laboratory studies are

the only means available for assessing potential impacts upon humans. Although there is usually no

direct, conclusive evidence that these effects are induced at the concentrations at which these chemicals are detected in groundwater, a variety of

information— qualitative human health studies conducted at sites of groundwater contamination (e.g.,

at Hardeman County, TN; Harris, et al., no date),

data on human health impacts of specific chemicals (whether studied directly in humans or indirectly in laboratory animals), and much anecdotal

information—suggests that the consumption of

groundwater contaminated with chemicals can result in acute, subchronic, and chronic human health

impacts. An important recent study shows a statistically significant relationship between two wells

contaminated with chloroform and TCE and elevated leukemia and birth defect rates in Woburn,

MA (reported in Science News, 1984).

Apart from the controversial nature of laboratory data, the information in appendix A.2 is a

limited data base because:

●

●

●

●

not all chemicals have been tested for all

impacts,

documentation is not available for cases in

which specific impacts were not observed during studies of specific chemicals,

chemicals that dominate the list of potential

health effects are the ones that have been most

thoroughly studied, and

the data were obtained from secondary sources.

Thus the purpose of appendix A.2 is not to establish either that effects will be realized with certainty

in exposed human populations or the probability

of their occurrence. Rather, the information shown

should be viewed as an indication of the nature of

potential human health impacts from substances in

groundwater.

A given effect can be caused by numerous chemicals (see app. A. 2). The effects associated with the

largest numbers of chemicals include (in decreasing order of the number of chemicals known to

cause these effects): eye and skin irritation, effects

on the central nervous system, liver damage, lung

and respiratory tract effects, kidney damage, cancers, and genetic mutation. Of these effects, and

depending on dosage, central nervous system

(CNS) damage, liver and kidney damage, and

cancers may be the most commonly expected serious forms of adverse health impacts associated with

known groundwater chemical contaminants (Environ Corp. , 1983). More specifically:

1. Liver, kidney, and CNS toxicants include

ethylbenzene and toluene (alkyl-substituted

benzenes); carbon tetrachloride, chloroform,

and TCE (halogenated aliphatic hydrocarbons); bromobenzene, PBBs, and PCBs (halo-
Ch. 2—Groundwater Contamination and Its Impacts ● 3 3

genated aromatic hydrocarbons); chlordane,

DDT, and toxaphene (chlorinated hydrocarbon pesticides); and some heavy metals.

2. Known or suspected carcinogens listed in table

1 include 32 of the organic chemicals-chlorinated aliphatic hydrocarbons and chlorinated

hydrocarbon pesticides—and 5 of the heavy

metals (3 of which may be active only via inhalation). The evidence for human carcinogenicity of some substances has been obtained

from human studies and is quite strong. There

is very little doubt that benzene, benzidine,

inorganic arsenic, vinyl chloride, chromium,

and nickel are human carcinogens (the latter

two, however, are not likely to be present in

groundwater in their carcinogenic forms).

Studies of experimental animals where the

predominant effect is on the rodent liver provide the main evidence for carcinogenicity of

chlorinated aliphatic hydrocarbons (e. g., carbon tetrachloride, chloroform, TCE, PCE,

and others; note from above that vinyl chloride is an exception) and chlorinated hydrocarbon pesticides (e. g., aldrin, chlordane, DDT,

dieldrin, heptachlor, toxaphene, and others).

It is also possible that nitrates are transformed

into nitrosamines, which are carcinogenic in

laboratory animals (NAS, 1977).

In a review of 31 substances commonly

found in groundwater (Crump, et al., 1980,

cited in Harris, 1983), two compounds with

known human carcinogenic effects were documented. In addition, 12 compounds (including six chlorinated aliphatic hydrocarbons and

four chlorinated hydrocarbon pesticides) had

carcinogenic effects in at least one laboratory

animal species and two compounds had effects

suggestive of carcinogenicity. Despite some

scientific debate on the biological relevance of

these findings for humans (Environ Corp.,

1983), Federal regulatory agencies consider

many of these substances potential human carcinogens. One compound had no observable

effects in preliminary tests, and 14 chemicals

had not even been tested in animal experiments.

3. Only a few compounds are known to be capable of damaging the reproductive system or

causing birth defects, but some of them are

widely used throughout society. The major

4.

In

substances in this category are DBCP, vinyl

chloride, EDB, benzene, toluene, and xylene

(Harris, 1983) and selected chlorinated ethanes and phthalate esters, PCBs, and the

chlorinated dibenzo-p-dioxins (Environ Corp.,

1983).

Skin and eye irritation, particularly during

showering and bathing, might be expected

when chemicals are found in groundwater.

Data suggest that these effects are reversible

upon cessation of exposure.

Potential Toxicity or

Potency of Chemicals

addition to requiring information on the general adverse effects of groundwater contammants,

a standard risk assessment analysis requires information on the non-carcinogenic toxicity and carcinogenic potency of the chemicals. That is, adverse

effects are associated with certain chemicals, but

they are elicited at only certain dosages and/or exposure levels—and different chemicals have different abilities to elicit those effects. As part of OTA’s

study, chemicals found in groundwater were ranked

according to their relative degree of non-carcinogenic toxicity and carcinogenic potency using doseresponse data when available (see table 1; Environ

Corp., 1983).2 Three broad categories are defined:

‘ ‘high, ‘‘ ‘‘moderate, and ‘ ‘low’; note that the

definitions shown in table 1 are different for noncarcinogenic toxicity and carcinogenic potency.

Based on these broad rankings, the following

general conclusions are drawn (Environ Corp.,

1983):

1.

2.

Some chemicals are of high toxicity and can

elicit non-carcinogenic responses (e. g., liver,

kidney, and CNS damage) at relatively low

doses and/or exposure levels. These chemicals

include endosulfan, endrin, and kepone (pesticides), and heavy metals (see table 1).

Many other chemicals with potential to affect

the liver, kidney, and CNS are of low to moderate toxicity and thus require higher doses

and/or exposure levels to elicit these effects.

‘The susceptibility of humans to various substances is also variable

among individuals and is affected by factors such as age, general health,

and genetic background.
34 “ Protecting the Nation’s Groundwater From Contamination

3.

These chemicals include trichlorofluoromethane, bromochloromethane, chloromethane,

and 1,1 -dichloroethane (halogenated aliphatic

hydrocarbons), bromobenzene and dichlorobenzene (halogenated aromatic hydrocarbons), and ethylbenzene and toluene (alkylsubstituted benzenes).

Substances with high to moderate carcinogenic potency can elicit carcinogenic responses at

relatively low doses and/or exposure levels.

These chemicals include aldrin, DDT, dieldrin, and chlordane (pesticides), carbon tetrachloride, chloroform, and 1,1 -dichloroethy -

lene (halogenated aliphatic hydrocarbons),

benzidine (an aromatic amine), and PCBs

(halogenated aromatic hydrocarbons).

There are substantial numbers of chemicals

known to occur in groundwater for which no toxicity or potency data are available (beyond some

acute effects). Approximately two-thirds of the

organic chemicals and one-half of the inorganic

chemicals listed in table 1 may not have associated

toxicity or potency data. 3 In addition, substances

not generally thought of in terms of toxicity or

potency (e. g., salt water, micro-organisms, or nitrates) can also contaminate aquifers, causing both

health and non-health impacts.

3Data may be available for these substances in sources not reviewed

by OTA.

Photo credit: State of Florida Department of Environmental Regulation

Research on health impacts will provide information

now lacking about many groundwater contaminants.

Interactions Among Multiple

Chemicals

One of the potentially most important, and as

yet relatively unexplored, health issues of groundwater contamination is that contaminated aquifers

usually contain more than one substance. Knowledge is almost totally lacking about possible interactions among combinations of substances. Such

interactions, in which subsequent impacts are qualitatively and quantitatively different than expected

(and usually greater—i.e., synergistic), are common in many chemical and biological processes

(Odum, 1971).

At least one type of synergistic interaction has

been identified that is of potential importance in

groundwater: the liver toxicity of carbon tetrachloride, TCE, and 1 ,1,1 -trichloroethane (halogenated

aliphatic hydrocarbons) is known from animal experiments to increase greatly in the presence of

alcohol. This effect has been confirmed in human

case studies for carbon tetrachloride and TCE

(Radike, et al., 1977; EPA, 1980a and b). Liver

toxicity of TCE and PCE is also affected by Aroclor

1254, a polychlorinated biphenyl (PCB) (see

NRDC, 1982; EPA, 1980c).

Biological Substances

Pathogenic biological organisms that have been

found in groundwater include:

1. bacteria (e. g., typhoid, bacillary dysentery,

cholera, gastroenteritis, and tuberculosis);

2. viruses (e. g., enteroviruses and hepatitis); and

3. parasites (e. g., protozoa, worms, and fungi).

The micro-organisms most frequently found in

groundwater are bacteria that inhabit the gastrointestinal tract, and the most common category of

disease resulting from micro-organisms in groundwater is gastrointestinal. Contaminated groundwater was identified as the cause of approximately

one-half of all outbreaks of acute waterborne disease occurring in the United States from 1971 to

1977, and bacterial contamination has been the

most frequently identified source of groundwaterrelated disease outbreaks (e. g., EPA cites 94 such

outbreaks between 1945 and 1980; see Environ

Corp., 1983). The potential for bacterial contami-
Ch. 2—Groundwater Contamination and Its Impacts • 35

nation of groundwater depends on both the survival

rate of the species and characteristics of the subsurface (e. g., moisture content, pH, and temperature). Bacterial contamination most commonly

results from the introduction of human (or animal)

fecal material, usually when septic tanks or cesspools leak or overflow (Environ Corp., 1983).

Viruses and parasites have been implicated in

groundwater contamination incidents in relatively

few instances. The low rate for viruses may be attributed to limitations in detection methods (Environ Corp. , 1983). The analytical limitations regarding detection of viruses, coupled with estimates

by the World Health Organization that about 60

percent of the cases of waterborne disease reported

in the United States are caused by unrecognized

or unknown agents, suggest that viral contamination of drinking water (including groundwater

sources) may be of greater significance than has

been recognized (Environ Corp., 1983). The principal sources of viruses in groundwater are sewage

effluent (e. g., from septic tanks, cesspools, and land

application practices), animal feedlots, and dairies.

The factors that affect the occurrence of viruses in

groundwater are complex and poorly understood;

it is likely that they are similar to those for bacteria.

Radioactive Substances

Most groundwater contains trace levels of naturally occurring radioactive substances or their byproducts. The types and levels vary from area to

area, depending principally on subsurface materials. In addition to natural radiation, radioactive

 A,---- A- L, -

Credit: Southeast Michigan Council of Governments, 1982

Septic systems can cause both biological and chemical contamination of groundwater and surface water.
36 . Protecting the Nation’s Groundwater From Contamination

substances in groundwater can result from human

activities. These sources include radioactive waste

disposal sites, waste tailings and piles, and mine

drainage related to uranium mining.

Health protection from radiation is a highly developed science, and data accumulated over many

years link adverse health effects and exposure. Importantly, health effects are generally understood

only at high exposure levels; only in isolated circumstances are these levels of radioactivity likely

to occur in groundwater. The National Academy

of Sciences, in its discussion of the health risks of

radioactive drinking water (NAS, 1977), estimated

total average body exposure from drinking contaminated water at less than 1 percent of total average

yearly background radiation exposure received by

the population (total exposure is approximately 100

mrem/year). The risk of cancer from total average

natural background radiation is estimated at 4.5

to 45 fatalities per million persons per year (estimates depend on particular assumptions; NAS,

1977), including 0.6 fatal cases of bone cancer per

million persons per year.

Because radioactive content can vary from average conditions, there can be situations in which

doses are significantly greater than average. For example, in areas with high groundwater radium levels (e. g., 25 pCi/liter of Ra226 and 12.5 pCi/liter

of Ra228), exposure of the human skeleton could

be as much as a sixfold increase (up to 600 mrem/

year) over that from all natural background sources.

Radiation in groundwater could thus be a serious

problem in localized areas, e.g., parts of New

England (Harris, 1984; Duncan, et al., 1976, cited

in Prichard et al., 1983). Under the “high”

groundwater radium levels mentioned above, the

risk of fatal bone cancer could increase to an estimated 4.2 fatalities per million persons per year.

Radiation exposure can also cause developmental

or teratogenic effects; the lowest dose at which any

developmental or teratogenic effect has been reported is 1,100 mrem/year. Under ‘ ‘average’ conditions, doses received by the population are so

small that no measurable developmental or teratogenic effects from drinking radioactive groundwater would be found, even during the sensitive

period of gestation (NAS, 1977).

NON-HEALTH IMPACTS

There is a general absence of both methodological experience and data on evaluating the nonhealth impacts—economic, environmental, and

social—of groundwater contamination. Examples

of these impacts are shown in table 2. Because available data are insufficient for quantifying or otherwise comparing most of these impacts, this section

focuses on the nature of non-health impacts and

the difficulties in their assessment.

Economic Impacts

Data about various types of economic impacts

associated with groundwater contamination are

generally not available (University of Oklahoma,

1983). The data that are available tend to be the

direct costs of corrective action; and they either encompass such a broad range that they are difficult

to interpret apart from site-specific conditions (e. g.,

Corrective actions can cost tens of millions of dollars

or more depending on site conditions), or they lack

sufficient documentation (e. g., in terms of describing site conditions) for subsequent comparison and

analysis. Some data may also be unobtainable because of their proprietary nature or use in litigation.

In addition to empirical difficulties, there are

methodological difficulties in assessing the value of

groundwater quality in terms of both the costs of

contamination and the benefits of protection. Few

studies are available that systematically approach

an assessment of economic impacts (see Raucher,

1983; Sharefkin, et al., 1983; Reitman, 1982).

These conceptual difficulties, some of them common to the assessment of impacts on other environmental media (e. g., surface water and air),

include:
Ch. 2—Groundwater Contamination and Its Impacts ● 3 7

Table 2.—Examples of Economic, Environmental, and Social Impacts

Resulting from Groundwater Contamination

Agriculture

Households

Municipalities

Economic impacts

Industry Higher operation/maintenance or capital costs (e.g., for accelerated repair or replacement of

damaged equipment or materials)

Lost output from downtime during repairs, during the search for alternative water supplies, and

during relocation

Relocation costs

Decreases in property value

Decreases in revenue if quantity of products sold or their prices fall as a result of lower product

quality

Secondary costs (e.g., incurred by suppliers to inputs to the industry or by receivers of the output

such as by processors or marketing agents)

Legal and administrative costs

Costs of detection, correction, and prevention activities

Higher operation/maintenance or capital costs (e.g., for accelerated repair or replacement of

damaged equipment or materials)

Loss of output due to damage to productivity of land (also reflected in decreases in property value)

Lost revenue from discarding of food products unsuitable for consumption

Loss of output due to injury or death to perennial plants and trees

Decreases in livestock productivity, including illness and death

Secondary costs (e.g., incurred by suppliers of inputs to agriculture or by receivers of output)

Legal and administrative costs

Costs of detection, correction, and prevention activities

Higher operation/maintenance or capital costs (e.g., for cleaning, replacement, and/or rehabilitation of

damaged pipes, plumbing, appliances)

Decreased value of residential property

Relocation expenses, including search costs, higher purchase prices, higher interest rates and fees,

and moving costs

Secondary costs (e.g., contraction or expansion of commercial activities)

Loss of income due to sickness

Legal costs

Costs of detection, correction, and prevention activities (e.g., pre-treatment and purchase of bottled

water)

Lost receipts from property, sales, or income taxes

Re-allocation of additional resources to provide emergency services

Costs of procuring alternative supplies

Legal and administrative costs

Detection, correction, and prevention activities

Environmental impacts

Aesthetics Odor

Taste

Appearance

Surface water

contamination by

groundwater

Biota

Air pollution

Soil contamination

Social impacts

Psychological stress

Inconvenience

Damage to vegetation, waterfowl, and aquatic life

Contamination of fish

Social disruption

SOURCE Off Ice of Technology Assessment

Ž determination of the effects of various activi- . selection of an appropriate time horizon for

ties and practices on groundwater quality; the analysis and an appropriate discount rate

● determination of the effects of changes in for the time value of money; and

groundwater quality on groundwater use; ● assessment of the cost and effectiveness of

● lack of a perfectly competitive economic mar- various approaches to detection, correction,

ketplace for valuing groundwater quality; and prevention of groundwater contamination.
38 Protecting the Nation’s Groundwater From Contamination

The economic damages resulting from groundwater contamination shown in table 3 illustrate the

types and magnitude of documented costs. Data

are easiest to obtain for perceptible, short-term effects on users that are reflected in the marketplace.

Importantly, although the real value lost to the Nation from any one incident may not be significant

compared to, say the gross national product, the

economic costs of groundwater contamination are

significant if the costs for all incidents are combined and if the time over which these costs will

be incurred is considered. In addition, the costs

to the Nation associated with the contamination of

many aquifers may well exceed the sum of the costs

associated with individual aquifers—e. g., if there

is widespread loss of potable drinking water or of

agricultural produce. Further, the economic damages from any one incident may be significant

from the perspective of the populations and users

affected. For example, cash-flow imbalances or

other dislocations (e. g., layoffs) can result, especially during emergencies when impacts may not

be anticipated or planned for.

Environmental and Social Impacts

Contaminated groundwater causes diverse environmental and social impacts; they are generally

not quantifiable and little documentation is

available.

Because groundwater provides a significant portion of baseflow to streams, the potential for adverse

impacts on surface water quality may be large, especially during periods of low rainfall when dilution

is minimal. Changes in the quantity of groundwater

also influence the quality of groundwater (e. g., the

pumping of groundwater can induce the migration

of contaminants). The extent of other environmental impacts is unknown; some cases document damage to fish, vegetation, and wildlife. The potential

for groundwater contaminants (e. g., volatile organics) to enter the atmosphere in the vicinity of certain sources (e. g., landfills) or from volatilization

during showering has now been recognized.

Social impacts are related largely to the anxiety

caused by fear and uncertainty about exposure to

contaminants. Exposure can occur unknowingly because many contaminants are odorless, colorless,

and tasteless. Exposure to contaminants occurs over

many years and via many pathways, including

drinking contaminated water, eating foods that

have been in contact with contaminated groundwater, bathing in contaminated water, and breathing contaminants when they volatilize in the shower. Social impacts also arise from decreased

property values, and from lost income because of

illness, relocation, and inconvenience (e. g., in procuring alternative water supplies).

CONCENTRATION AND FREQUENCY OF

SUBSTANCES FOUND IN GROUNDWATER

Concentration of Substances

in Groundwater

A substance is ‘ ‘detected’ or ‘ ‘reported” if its

concentration sufficiently exceeds the detection limits of sampling and measurement equipment so that

its presence is verifiable. Detection limits (typically

referred to as ‘‘trace levels’ imply that values

below the measurement threshold will not be

reported as positive even if substances are in fact

present at lower concentrations.

A wide range of concentrations of various substances has been found in groundwater (table 1).

The most important conclusions about the concentration data are:

. concentrations of substances in groundwater

are site-specific and thus are highly variable

spatially;

. concentrations are highly variable temporally—they may fluctuate at a particular site by

a factor of 10 during the course of a year (Har-
Location Contaminants Nature of costs Direct costs incurred Documentation

Canton, CT Well closings; extension

of water lines to

affected areas

$145,000-379,000 CRS, 1980a

Oscoda Ml

South Brunswick, NJ

Cohansey Aquifer, NJ

Well closings; provision of

new source of water

Well closings; extension of

municipal water lines to affected area

Well closings (148); removal

of drums; interim

emergency water supply

(via tanker trucks); drilling

of new wells; extension of

public water supply (60°/0

of total monetary costs)

Loss of irrigation well

Partial rice crop loss

Estimated loss in profits

for changing from irrigated

to nonirrigated crops

Reduced service lives of house.

hold plumbing and

appliances

$140,000

300,000

CRS, 1980a

Chloroform, toluene, CRS, 1980a

xylene, trichloroethane,

trichloroethylene

Wastes from manufacture of organic chemicals, plastics, resin

$417,000

(Residential cost of

water increased from

an average of $45/year

to $75/year)

U.S. EPA, 1976

CRS, 1980b

Miller County, AR Brine contamination

from oil and gas

activities

$4,000

$36,000

$150/acre/year for rice

$35/acre/year for cotton

$20/acre/year for soybeans

Increased annual capital

cost per household of

40% as total dissolved

solids increase from

250 ppm to 1,750 ppm

$2 million

Fryberger, 1972

38 communities in 11

Midwestern Statesc

Mineral content Patterson, et al., 1968

As reported in Sharefkin,

et al., 1983

Atlantic City, NJ Chemical wastes

(Price’s Landfill)

Estimated cost of new well

field to replace contaminated

wells

Cost of alternative water supply

to 35 private residences

Estimated cost of reduced

service lives of household

plumbing and appliances

Estimated average annual cost

of water softeners or increased cost of cleaning

products

Estimated average costs of

using bottled water

Loss of farm income

Loss of farm income

Alternative water supply for

affected area

Purchase of water by residents

Connection to district water

supply

$250,000

$6.5 million total annual

capital cost

$12.3 million

Orange County, CAd Mineral content Orange County Water District,

1982

$2.2 million

$5 million per year

$31.2 million per year

$180,000

$3-5 per 5 gallons

$150 per connection,

monthly operating

costs of $4-1o

$1.2 million

Montana

San Joaquin Valley, CA

Auburn, MA

Lathrop, CA

Miller, 1980

Sheridan, 1981

U.S. House of Representatives,

1980

CRS, 1980b

Salinity

Salinity

Unspecified chemicals

Pesticides

Jackson Township, NJ Chloroform, methyl Costs of planned water system

to replace closing of 100

wells

CRS, 1980a

chloride benzene

toluene, trichloroethylene, ethylbenzene, acetone
40 • Protecting the Nation’s Groundwater From Contamination

ris, et al. , no date), and they may vary from

day to day (Harris, 1984);

● concentrations of substances are often many

times higher in groundwater than in surface

water; and

● higher concentrations of substances are typicall y found near the site of their release

(Westerhoff, et al., 1982), especially if that site

contains concentrated amounts of the substance, sources are numerous, and/or the site

is characterized by relatively permeable soils.

A number of surveys focusing on public drinking water wells have been conducted by the States

and the Federal Government in the last 10 years—

including the early Environmental Protection Agency (EPA) National Organics Reconnaissance Survey (NORS) and National Organics Monitoring

Survey (NOMS) and, more recently, the Community Water Supply Survey (CWSS) and Ground

Water Supply Survey (GWSS).4 Efforts in these

studies were oriented toward detection of volatile

organic chemicals (VOCs), as opposed to nonVOCs (NAS, 1977). These studies show that volatile organic compounds are frequently present at

detectable concentrations in public drinking water

wells.5 The studies also reveal that concentrations

of compounds in groundwater are often much

higher than in surface water; for example, TCE,

toluene, and 1,1,1-trichloroethane are up to 1,000

times more concentrated in groundwater than in

surface water (Burmaster, et al. , 1982).6

The National Inorganic and Radionuclides Survey (NIRS) is an ongoing EPA study of groundwater-supplied community water systems; 38 inorganic (26 of which have already been detected

in groundwater), 4 radionuclides (all previously

detected in groundwater), and 2 common measures

of radioactivity are the focus of this investigation.

Because of the site-specific nature of groundwater

contamination, it is not possible to draw more detailed conclusions about or to predict typical contaminant concentrations. At best, concentration

data indicate the severity of site-specific contamination problems and immediate local risks to public

health and the environment (see the sections on

Standards and Health Impacts). Such data are also

essential to determine the suitability of alternative

corrective actions (see ch. 8).

Generalizations about concentration data at any

level more aggregated than at an individual site

are highly tentative. Systematic collection of data

in space or time can show how concentrations vary

in an area and can provide historical information,

thus establishing contamination trends for a particular source and/or type of hydrogeologic setting.

In all cases, however, the concentration data are

snapshots at one point in time and thus do not take

into account the dynamics of system behavior.

Frequency of Occurrence of

Substances in Groundwater

Frequency of occurrence generally refers to the

number of positive samples (i. e., number for which

the substance of concern is detected) in the total

number of samples tested. Like concentration data,

frequency data can be biased by sampling procedures and analytical detection limits (University of

Oklahoma, 1983; Westrick, et al., 1983). In addition, data are not usually collected with sufficient

detail for frequency analysis (e. g., detection limits

of the measuring instrumentation are often not

specified), and there may be no information available on frequency distributions. Most importantly,

there is often no attempt to link frequency data with

concentration data; thus a ‘ ‘positive’ sample implies that the substance is detectable, but it does

not indicate the concentration.

Interpretation of frequency data is more meaningful if information is also available about such

factors as historical land uses and sources. At least
Ch.2—Groundwater Contamination and Its Impacts ● 41

at the site-specific level, frequency data can give

an impression of the pervasiveness of substances

in groundwater. From a regional or national perspective, however, interpretation of frequency data

becomes much more difficult. Nationwide frequenc}’ studies would require extensive sampling (hundreds to thousands of sites) and, like concentration

studies, would provide only snapshots.

With these limitations in mind, data concerning

the frequency of occurrence for specific chemicals

are summarized in appendix A.3. The national surveys listed in the section on Concentration of Substances in Groundwater (NORS, NOMS, CWSS,

GWSS), the National Screening Program for Organics in Drinking Water (NSP), and some State

surveys have all yielded data on the frequency of

organic chemicals in groundwater-supplied drinking water. Information on the percentage of total

groundwater samples in Federal surveys which contained detectable levels of VOCs is summarized by

Coniglio (1982).

General conclusions about the frequency data

are:

c

●

●

several organic chemicals associated with

chlorinated solvents, especially TCE and PCE,

have frequently been detected in groundwater

contamination incidents;

public drinking water systems relying on

groundwater are frequently contaminated with

VOCs; and

two or more VOCs are frequently detected simultaneously in groundwater supplies.

In studies of drinking water wells conducted by

18 States, frequencies of detection of various VOCs

were compiled for both random and non-random

samples (CEQ 1981). For the most common chemicals in the random samples, frequency of detection ranged among the States from 1 .7-11.3 percent for TCE and from 3.6-4.5 percent for 1,1-

dichloroethane. Random samples both are more indicative of general conditions and generate more

conservative estimates than non-random samples.

The two most recent Federal studies (CWSS and

GWSS) provide much information regarding frequency of VOCs in groundwater. Information from

the CWSS indicated that 15 percent of public water

systems relying on groundwater contained at least

one VOC; VOCs were detected in 45 percent of

the public water systems serving more than 10,000

people and in 12 percent of the more numerous

public water systems serving fewer than 10,000 people. Because the samples were 1-2 years old at the

time of analysis, some VOCs may have degraded;

thus, these percentages are regarded as minimum

estimates (Brass, et al. , 1981, cited in NRDC,

1982).

The GWSS (Westrick, et al., 1983) provides information on the frequency with which one or more

VOCs were detected in groundwater samples. In

the GWSS, random samples of groundwater supplies from public water systems were collected from

466 randomly selected communities. The percentage of random samples with one or more VOCs

detected was 16.8 percent for small systems (serving fewer than 10,000 people) and 27.9 percent for

large systems (serving more than 10,000 people).

TCE and PCE were detected in 3.2 percent and

4.6 percent of the random samples from small systems, respectively, and both were detected in 11.3

percent of the random samples from large systems.

More importantly, the percentage of random samples with two or more VOCs present was 6.8 percent for small systems and 13.4 percent for large

systems. An additional part of the survey focused

on non-random supplies selected by State agencies.

Concentration and Frequency Data in

Relation to Governmental Standards

Evaluation of health risks associated with groundwater contamination requires, among other things,

information concerning both frequency and concentration of substances—specifically, the frequency

with which groundwater contains one or more substances at concentrations exceeding levels that are

considered unsafe. Standards promulgated by government agencies specify those limits above which

the presence of a substance is considered unsafe;

they thus serve as a gauge of the potential impacts

of contamination. Concentration data alone can reveal potential problems, but only if they can be

compared with standards or health impact data related to those specific concentrations.

No Federal standards have been developed specifically for substances found in groundwater. But
42 ● Protecting the Nation’s Groundwater From Contamination

various Federal standards and guidelines-some developed for drinking water-have been applied to

groundwater. These include National Interim

Drinking Water Regulations (Primary and Secondary), Health Advisories, and Ambient Water Quality Criteria. In addition, individual States have developed standards which they are applying to

groundwater, including State drinking water standards and State groundwater standards (see chs. 3

and 4 and app. C. 3 for additional information related to standards).

Standards or guidelines of some type (State or

Federal) have been promulgated for less than onehalf the substances that have been detected in

groundwater (refer to table 1). Although Federal

standards or guidelines exist for over 60 substances,

there are only 22 enforceable standards (established

by the National Interim Primary Drinking Water

Regulations) and of these, 18 are for individual

substances. An additional six Federal standards are

non-enforceable under the Secondary Relations;

remaining standards or guidelines are Health Advisories or Ambient Water Quality Criteria. Over

150 substances and other quality indicators have

State standards; less than one-half of them also have

some type of Federal standard or guideline.

Because there is no consistent approach to the

development of standards, because different standards are used by different Federal and State agencies, and because standards do not exist for many

substances, people in different States do not receive a uniform level of health protection against

groundwater contaminants. For example, some

States (especially in the Northeast, but also in other

parts of the country) have closed contaminated

drinking water wells in order to prevent human exposure to specific chemicals (e. g., TCE, PCE, dichloroethane, benzene, chloroform, toluene, and

vinyl chloride; Environ Corp. , 1983). Concentrations of the chemicals in the closed wells almost

always exceeded Ambient Water Quality Criteria,

but the levels at which the wells were closed varied

greatly from State to State. For example, wells in

New York, Rhode Island, and Massachusetts were

closed at levels of tetrachloroethylene ranging from

1-61 parts per billion (Ambient Water Quality Criterion = 0.8 ppb); and wells in New York and

Rhode Island were closed at levels of 1,1,1-trichloroethane ranging from 3-1400 ppb (Ambient Water

Photo credit: State of Florida Department of Environmental Regulation

About one-half of the Nation’s population depends on

groundwater for drinking, and the level of health protection

against groundwater contaminants varies from State to State.

Quality Criterion = 18.4 ppb). Although these data

indicate the levels at which wells were closed, they

do not indicate the minimum threshold concentrations that would have elicited well-closing decisions

(Environ Corp., 1983).

Theoretically, frequency data could be linked

with concentration data and various standards to

ascertain the percentage of contamination incidents

in which some type of standard is exceeded. If the

standard reflects an exposure level that could result in adverse health effects, then this type of analysis would yield information on the frequency with

which the public is exposed to unsafe concentrations of contaminants in groundwater. In general,

both concentration and frequency data are usually

not reported in enough detail for such an analysis.

OTA’s study attempted such an analysis, as a

first approximation, for examples with sufficient

data. Documentation showed 38 organic chemicals,

25 inorganic chemicals, and two radionuclides for

which concentrations in at least one groundwater

sample are known to have exceeded one or more

of the above types of standards or guidelines (see

app. A.4 for details of which standards or guidelines have been exceeded). Of these 65 substances,

14 (3 organics, 10 inorganics, and 1 radionuclide)

involve National Interim Primary Drinking Water

Regulations, and an additional 5 inorganic chemicals involve Secondary Regulations. In most cases

where standards or guidelines were exceeded, State
Ch. 2—Groundwater Contamination and Its Impacts ● 43

standards or Ambient Water Quality Criteria were

involved.

Frequency and concentration data are available

for 13 of the 38 organic chemicals known to exceed

some standard or guideline in at least one sample;

for none of these 13 compounds have the National

Interim Primary or Secondary Drinking Water

Regulations been promulgated. Calculations indicate that 4 of the 13 compounds are known to

exceed at least one type of standard or guideline

in .5-10 percent of groundwater contamination incidents (the type of standard or guideline exceeded

is shown in parentheses in the following list):

1.

2.

3.

4.

carbon tetrachloride (State groundwater and

Ambient Water Quality);

1,1-dichloroethylene (Ambient Water Quality);

tetrachloroethylene (Ambient Water Quality);

and

trichloroethylene (Ambient Water Quality).

This list is not intended to be exhaustive; rather,

it documents situations where substances are known

to exceed specified standards or guidelines frequently.

POTENTIAL BUT AS YET UNDETECTED

SUBSTANCES IN GROUNDWATER

Many substances have the potential to enter

groundwater because of their molecular properties

and association with sources (see the section on

Association of Substances Found in Groundwater

With Sources, which follows); they may already

be present in groundwater but have not yet been

detected. This study has been unable to determine

whether these substances have not yet been detected

because they are not being looked for, or are being looked for but have not been found. A number of them are known or are suspected to exhibit

toxic properties. Table 4 presents some generalizations about potential groundwater contaminants

that could have serious health effects; these generalizations are derived primarily from animal experiments. Table 4 should not be viewed as either

exhaustive or definitive. It appears that some, but

not all, of the contaminants of potential concern

can be detected with standardized analytical methods (Environ Corp., 1983).

TYPES OF SOURCES AND ASSOCIATED SUBSTANCES

Types of Sources

The quality of groundwater is altered by a wide

variety of human activities and naturally occurring

situations. Sources are points along the pathways

that substances travel as they flow through society,

where the substances can be released into groundwater. To illustrate, substances can be stored in or

flow through sources in a variety of ways, from the

storage of raw materials (e. g., materials stockpiles)

to manufacturing (e. g., product storage) to distribution (c. s., pipelines) to use (e. g., pesticide applications) to disposal (which can take place almost

an?’where in the process).

OTA’s study has identified 33 sources known to

have contaminated groundwater and has categorized them based on the nature of their release of

substances to groundwater (table 5). It is important to note that these categories are for the convenience of discussion. Depending on emphasis, a

source could be categorized in another way. For

example, non-waste injection wells (for enhanced

recovery and artificial recharge) could be placed in

Categories I or V. In addition, sources interact with

each other—a leak from an above ground storage

tank could result in substances entering groundwater directly (Category II) or entering urban runoff and, subsequently, groundwater (Category IV).
44 . Protecting the Nation’s Groundwater From Contamination

Table 4.—Potential Groundwater Contaminants

Displaying Serious Adverse Health Effectsa

Compound or class Potential effects

Acrylonitrile

Alkyl lead compounds

Alkylamines and alkanolamines (alkyl polyamides,

secondary amines)

Carbon disulfide

Dimethyl sulfate

n-Hexane

Mercaptans

N-Nitrosamines

Pesticides which are not included in Table 1.1

Phenols which are not included in Table 1.1

Propylene oxide

Carcinogenicity

Neurotoxicity; damage to

kidneys and hematopoietic system

Allergic sensitization; liver

and kidney injury; potential to form carcinogenic N-nitrosomines

Neurotoxicity

Carcinogenicity; mutagenicity

Neurotoxicity

CNS depression; liver and

kidney damage

Carcinogenicity

Neurotoxicity; enzyme

inhibition

Neurotoxicity; variety of

systemic effects

Suspect carcinogenicity;

mutagenicity

additional details in Environ Corp., 1983.

SOURCE: Off Ice of Technology Assessment

Other categorization schemes are also possible

(e.g., according to the nature of the user: agricultural, industrial, domestic, and municipal; or the

physical location of the source: above the land surface, below the land surface and above the groundwater table, and below the groundwater table).

However, classification based on discharge characteristics has the advantage of identifying and

characterizing the entry of substances into the

groundwater system. The points-of-entry, in turn,

are places where actions can be taken to discover

and alter the entry—i.e., to detect, correct, and prevent contamination.

Three general conclusions can be reached from

this categorization:

1. There is a great diversity of sources, and they

are associated with a broad range of industrial, agricultural, commercial, and domestic

activities. Both wastes and non-wastes are potential contaminants of groundwater. However, most attention has been focused on

wastes, particularly hazardous wastes, from

point sources or clusters of point sources. (A

‘‘point’ source is an easily identified facility,

such as a landfill or impoundment. )

2

3.

Only a few source types (Category I) are specifically designed to discharge substances (i. e.,

wastes) into the subsurface.

Non-waste releases result from some sources

designed to retain non-waste products (Categories II and III) and as a consequence of

other activities (Category IV) or altered flow

patterns (Category V).

Association of Substances Found in

Groundwater With Sources

The occurrence of substances in groundwater

and an understanding of how, why, and where they

are present are directly related to their use and/or

disposition. One way of approaching this topic is

to examine the association of various substances

with specific sources.

Rather than examine all substances shown in

table 1 individually, this study relates nine general

classes of substances to specific sources7 (table 6).

Classes of substances with the potential to be found

in association with a source are also indicated.

Table 6 does not represent a comprehensive survey

of the literature, even though one was attempted.

New information about actual contamination incidents is being obtained continually, especially as

the States survey their groundwater resources or

ings in the hierarchy. The groupings shown deviate from conventional approaches to contaminant categorization: these groupings are based

on molecular properties as well as detectability; conventional categories are based strictly on molecular properties (and thus tend to be

more detailed).
Ch. 2—Groundwater Contamination and its Impacts ● 4 5

Table 5.—Sources of Groundwater Contamination

Category l—Sources designed to discharge substances

Subsurface percolation (e.g., septic tanks and cesspools)

Injection wells

Hazardous waste

Non-hazardous waste (e.g., brine disposal and drainage)

Non-waste (e.g., enhanced recovery, artificial recharge,

solution mining, and in-situ mining)

Land application

Wastewater (e.g., spray irrigation)

Wastewater byproducts (e.g., sludge)

Hazardous waste

Non-hazardous waste

Category 11—Sources designed to store, treat, and/or

dispose of substances; discharge through unplanned

release

Landfills

Industrial hazardous waste

Industrial non-hazardous waste

Municipal sanitary

Open dumps, including illegal dumping (waste)

Residential (or local) disposal (waste)

Surface impoundments

Hazardous waste

Non-hazardous waste

Waste tailings

Waste piles

Hazardous waste

Non-hazardous waste

Materials stockpiles (non-waste)

Graveyards

Animal burial

 Aboveground storage tanks

Hazardous waste

Non-hazardous waste

Non-waste

Underground storage tanks

Hazardous waste

Non-hazardous waste

Non-waste

Containers

Hazardous waste

Non-hazardous waste

Non-waste

Open burning and detonation sites

Radioactive disposal sites

Category Ill–Sources designed to retain substances during

transport or transmission

Pipelines

Hazardous waste

Non-hazardous waste

Non-waste

Materials transport and transfer operations

Hazardous waste

Non-hazardous waste

Non-waste

Category IV—Sources discharging substances as

consequence of other planned activities

Irrigation practices (e.g., return flow)

Pesticide applications

Fertilizer applications

Animal feeding operations

De-icing salts applications

Urban runoff

Percolation of atmospheric pollutants

Mining and mine drainage

Surface mine-related

Underground mine-related

Category V—Sources providing conduit or inducing

discharge through altered flow patterns

Production wells

Oil (and gas) wells

Geothermal and heat recovery wells

Water supply wells

Other wells (non-waste)

Monitoring wells

Exploration wells

Construction excavation

Category Vi—Naturally occurring sources whose discharge

is created and/or exacerbated by human activity

Groundwater—surface water interactions

Natural leaching

Salt-water intrusion/brackish water upconing (or intrusion of

other poor-quality natural water)

SOURCE Office of Technology Assessment.

respond to contamination incidents, inventory

sources, and monitor supplies, and as efforts are

undertaken to recover and/or remove substances 2.

prior to their entry into the groundwater.

Four general conclusions can be drawn from this

table:

1. A diversity of classes of substances is associated with known sources of contamination.

The most common are the metals/cations and

non-metals/anions, followed by hydrocarbons

with specific elements (e. g., pesticides and

chlorinated solvents), miscellaneous hydrocarbons (e. g., fuels), and radionuclides.

The association of substances with specific

sources often varies according to the nature

of the use and disposal of substances by different segments of society. For example, pesticides may enter groundwater from the storage tanks of manufacturers, from aerial

spraying during agricultural operations, and

from residential disposal in backyards. In contrast, because of their design and operating

constraints (see app. A.5), radioactive disposal
46 ● Protecting the Nation’s Groundwater From Contamination

Photo cradlt: State of Florfda Department of Environmental Regulation

Wafer supply well

~ ~ 1 Unsaturated zone

Saturated zone

Credit: USGS, 14

3,

4.

sites are not likely to contain many organic

chemicals. In addition, substances associated

with a source are not necessarily found at

every facility of a given source type, and they

can vary from facility to facility and over time

at a given facility. The essential conclusion is

that generalizations about the association of

substances with sources are not possible —

specific substances associated with a single

source depend on past and present uses, and

thus the association of substances with sources

is highly site-specific.

Almost all sources are likely to release simultaneously a number of substances with very

different properties. Eight sources (subsurface

percolation, disposal wells, land application,

landfills, open dumps, residential disposal,

surface impoundments, and underground

storage tanks) have already been associated

with substances from five or more classes, and

an additional nine sources have a similar potential (table 6). Even if only one class of substances is involved in a particular situation,

many individual substances within that class

could be present, and their properties (e. g.,

toxicity) could vary.

For sources associated with particular activities (e. g., agricultural practices and materials

storage), fewer classes of substances are likely

to be found combined. Even then, however,

a broad range of substances may be present

in groundwater, depending on past and present land uses.

Poorly constructed and maintained or abandoned wells

can provide a conduit for the introduction of

contaminants into groundwater because of, for

example, the migration of water through corroded

casings. In this case, uncontrolled discharge from an

artesian well is causing brackish water upconing.
Ch. 2—Groundwater Contamination and Its Impacts ● 4 7

Photo credit: U.S. .Environmenta/ Protection Agency

Residential disposal as a source of groundwater contamination involves the

indiscriminant disposal of household products.

FACTORS

TO

INFLUENCING A SOURCE’S POTENTIAL

CONTAMINATE GROUNDWATER

The extent to which a source has the potential

to contribute to groundwater contamination depends on factors that characterize both the general

type of facility or activity (e. g., all landfills) and

the particular facility or activity of concern (e. g.,

a specific landfill). These factors include:

● design, operation, and maintenance characteristics;

● release characteristics;

● geographic location (pervasiveness and regionality);

. number of sources and amounts of material

flowing through or stored in sources; and

● hydrogeology.

Design, operation, and maintenance can influence a source potential to contribute substances

to groundwater through faulty operation and maintenance procedures or through mechanical failure

or deterioration; these factors are relatively random.

Release characteristics, pervasiveness and regionality, and the number of sources and amounts of

material are described in this section. (For general

descriptions of sources and details of calculations,

see app. A.5. )

Hydrogeology is site-specific, and it influences

the potential contribution of individual facilities or

activities primarily by affecting the movement of

substances into and within groundwater. (See ch.

5 for a discussion of hydrogeologic factors and investigative techniques. )

Release Characteristics

Potential sources of groundwater contamination

are highly variable in the spatial (areal) pattern of

their releases (table 7). These releases can be: 1)

discrete releases, where substances emanate from

a single identifiable unit; 2) diffuse releases over

a large area, so that substances cannot be traced

to a single identifiable source; or 3) frontal or

boundary releases, which may or may not emanate
48 ● Protecting the Nation’s Groundwater From contamination

Table 6.—Sources and Classes of Associated Substancesa

Organic chemicals Inorganic chemicals Biological Radionuclides

I

Category I

Subsurface percolation

Injection wells

Land applicationb

a Wastewater

b Wastewater byproducts

c. Hazardous waste

Category II

Landfills

Open dumps

Residential disposal

Surface impoundments

Waste tailings

Waste piles

Materials stockpiles

Graveyards

Animal burial

Above-ground storage tanks

Underground storage tanks

Containers

Open burning and

detonation sites

Radiooactlve disposal sites

Category I I I

Pipelines

Materials transport and

transfer operations

Category IV

Irrigation practices

Pesticide applications

Fertilizer applications

Animal feeding operations

De-icing salts applications

Urban runoff

Percolation of

atmospheric pollutants

Mining and mine drainage

 Potential exists for contaminant in class to be found in groundwater associated with source.
Ch. 2—Groundwater Contamination and Its Impacts ● 4 9

Table 6.—Sources and Classes of Associated Substances—Continued

Category V

Production wells

a 011

b Geothermal and heat recovery

c Water supply

Other wells

Construction excavation

Category VI

Ground Water surface water

I Interactions

Natural leaching

Salt water Intrusion

from a single source but which generally impact

groundwater along a front or boundary.

The first pattern, discrete releases, is typical of

point sources; diffuse and frontal release describe

non-point sources. But there are exceptions. For

example, point sources may be so densely situated

(e. g., oil production fields) that substances are released in an essentially diffuse pattern, and no single

source can be identified. If numerous different types

of point sources are located in an area (e. g., urban area), the specific source of the substances

found in groundwater may also be obscured. For

these reasons, the categorization of a source according to spatial release patterns is often site-specific

and thus not rigid.

Sources also vary in the temporal pattern of potential releases (table 7). Some sources that are active year-round are influenced by seasonal patterns

of rainfall and recharge (e. g., subsurface percolation, materials stockpile runoff, and natural leaching). Other year-round sources are not affected by

the elements because their associated materials are

enclosed or otherwise protected from climate (e. g.,

storage tanks and containers); in these cases, releases are random with respect to season. Some

sources are active only at certain times of the year

(e. g., agricultural activities and de-icing salts applications).

The age of an individual facility may also influence temporal release patterns. For example, more

concentrated levels of substances may be released

during the active years of a facility’s operations,

or if there is increasing mechanical failure or deterioration over time. Salinity from irrigation flow

(a Category IV source, which is seasonal in intensity) may also be age-dependent in salts built up

in the soil over time.

Geographic Location: Pervasiveness

and Regionality

Sources of groundwater contamination are either

widespread throughout the Nation, located in a few

concentrated areas or regions, or extremely localized (table 7). The majority of widespread sources

are point sources; they are numerous but also tend

to be concentrated in heavily populated areas. Most

point sources are Category II sources and are wasterelated (e.g., landfills and surface impoundments).

Some non-waste point sources (e. g., storage tanks

and water supply wells) and, importantly, some

non-point sources (e. g., pesticide applications and
50 ● Protecting the Nation’s Groundwater From Contamination

Table 7.—Summary of Source Characteristics

Individual facility/activity Aggregate of facilities/activities

Spatial Temporal Diversity

release release of known Amounts of

Purposeapatternbpatternc Pervasivenessdcontaminantse Numbersf materialg

Category I

Subsurface percolation .

Injection wells . . . . . . .

Land application . . . . . .

Category II

Landfills. . . . . . . . . . . . .

Open dumps . . . . . . . . .

Residential disposal . . .

Surface

impoundments . . . . .

Waste tailings . . . . . . . .

Waste piles . . . . . . . . . .

Materials stockpiles . .

Graveyards . . . . . . . . . . .

Animal burial. . . . . . . . .

Aboveground storage

tanks . . . . . . . . . . . . . .

Underground storage

tanks . . . . . . . . . . . . . .

Containers. . . . . . . . . . .

Open burning and

detonation sites. . . . .

Radioactive disposal

sites . . . . . . . . . . . . . . .

Category Ill

Pipelines . . . . . . . . . . . .

Materials transport and

transfer operations . . .

Category IV

Irrigation practices . . . .

Pesticide

applications . . . . . . . .

Fertilizer applications . . .

Animal feeding

operations . . . . . . . . . .

De-icing salts

applications . . . . . . . .

Urban runoff . . . . . . . . .

Percolation of

atmospheric

pollutants . . . . . . . . .

Mining and mine

drainage. . . . . . . . . . .

Category V

Production wells. . . . . .

Other wells . . . . . . . . . .

Construction

excavation . . . . . . . . .

Category VI

Groundwater-surface

water interactions. . . .

Natural leaching . . . . . .

Salt-water intrusion. . . .

NW

NW

NW

w

NW

w

w

w

NW

w

w

NW

High

Moderate

Moderate

High

High

High

High

Moderate

Moderate

Low

Moderate

Low

Low

Moderate

Low

Low

Low

Low

Moderate

Low

Low

Moderate

Low

Low

Moderate

Low

Moderate

Moderate

Low

Low

Low

Moderate

NW D,F s Moderate

High

High

Moderate

High

Moderate

?

High

?

High

Moderate (?)

Low (?)

Low

Moderate

Moderate

Moderate

High

High

Moderate

?

Moderate

?

High

High

?

?

NA

NA

NA

High

High

Low

Moderate

(High?)

Moderate

7

High

High

High

High

?

7

7

Moderate

Moderate

Low

Low

High

Moderate

Moderate

Low

Moderate

LOW

Moderate

?

?

Low (?)

Moderate

?

Moderate

?

?

?
Ch. 2—Groundwater Contamination and Its Impacts ● 5 1

urban runoff) are also widespread. But widespread

point sources may be of greater concern in some

regions than in others because of variations in hy -

drogeology or the level of dependence on groundwater.

Regional sources tend to be associated with heavily populated areas or major economic activities;

often they are numerous or have large amounts of

material associated with them. They include sources

in Categories I, II, V, and VI. For example, septic tanks are relatively more concentrated in California and the Northeast, fertilizers and pesticides are

applied primarily in the West and Midwest, brine

disposal wells are located primarily in the Southwest, and mine drainage is found mostly in the

East, Midwest, and Southwest. A regional source

such as salt-water intrusion is naturally limited to

certain coastal areas. In addition, because the distribution of sources is dynamic (e. g., industrialization is increasing in the South, and energy development is increasing in Appalachia and in the

Midwest), sources related to previous land uses,

rather than present-day activities, may be responsible for the contamination.

The regional nature of some activities does not

preclude their associated substances from becoming widespread. For example, only a few manufacturers are primary producers of the active ingredients in pesticides, but their products are used

by intermediate manufacturers, small industries,

residential households, and agricultural operations

throughout the country.

Maps could be used to show the predominance

of sources on a regional scale as well as the pervasiveness of sources nationwide. Maps are not included in this report for two major reasons:

1. Available maps generally refer to one source

or to several related sources. Because the information contained on different maps involves different assumptions and levels of detail, the relative importance of different

sources is difficult to ascertain.

2. Most importantly, site-specific conditions (including hydrogeology), which are essential for

any conclusions or predictions about groundwater contamination, are not included on

these maps. Relationships would need to be

established between source locations and hy -

drogeologic areas most vulnerable to the entrance and subsequent movement of substances in groundwater and source locations.

Numbers of Sources and Amounts

of Material Flowing Through

or Stored in Sources

Current estimates of the number of sources and

the amounts of materials flowing through or stored

in these sources are presented in table 8. As can

be seen, many of the estimates in the 1977 Report

to Congress (EPA, 1977; Miller, 1980) are updated,

and initial estimates for many additional sources

have been developed in OTA’s analysis. Details of

the calculations are in appendix A.5.

At least four limitations are inherent in these

estimates:

1.

2.

3,

The estimates are specifically for the amounts

of material flowing through or stored in the

source and are not estimates of the amounts

of material actually reaching the groundwater

(unless otherwise indicated). Thus the estimates suggest only the maximum potential for

groundwater contamination.

An estimate of the amount reveals nothing

about the nature and concentration of substances in that material. Industrial and municipal sludge provides an example. The

amount of industrial sludge used in land applications is roughly 7 percent of that used

from municipal systems, yet often the chemical compounds or their concentrations in industrial sludge (e. g., inorganic acids and

higher concentrations of hydrocarbons) pose

greater health threats than the chemical compounds found in municipal sludge.

Accuracy of the quantitative estimates varies

considerably from source to source, depending

on the underlying assumptions and completeness of the data. This study has attempted to

address this problem by indicating the range

of values within which the true value probably falls (see app. A.5 for details), but even

this approach is arbitrary. It is important to

remember that there is a high degree of uncertainty underlying the estimates and that
52 ● Protecting the Nation’s Groundwater From Contamination

Table 8.—Numbers of Sources and Amounts of Material Flowing Through or Stored in Sourcesa

OTA Update 1977 Report

Possible Possible

Approximate Approximate uncertainty uncertainty Approximate

number of amount of in number in amount amount of

Source facilities material b

estimate c

estimate c material

Category I

Subsurface percolation

Domestic. ... , . . . . . . . . . . .

Industrial . . . . . . . . . . . . . . . .

Injection wells

Hazardous waste . . . . . . . . .

Drainage, etc. . . . . . . . . . . . .

Brine . . . . . . . . . . . . . . . . . . .

Non-waste (enhanced

oil recovery) . . . . . . . . . . . I

Non-waste (solution,

in-situ) . . . . . . . . . . . . . . . .

Land application

Municipal sludge . . . . . . . . .

Industrial hazardous waste .

Spray irrigation . . . . . . . . . . .

Category II

Landfills

Industrial hazardous

waste. . . . . . . . . . . . . . . . .

Industrial nonhazardous waste. . . . . . . .

Utility. . . . . . . . . . . . . . . . . . .

Municipal . . . . . . . . . . . . . . .

Open dumps. . . . . . . . . . . . . . .

Residential disposal sites . . . .

Surface impoundments. , . . .

Hazardous waste . . . . . . . . .

Non-hazardous waste. . . . . .

Waste tailings. . . . . . . . . . . . . .

Waste piles

Hazardous waste . . . . . . . . .

Non-hazardous waste. ... , .

Materials stockpiles . . . . . . . . .

Graveyards. . . . . . . . . . . . . . . . .

Animal burial . . . . . . . . . . . . . .

Aboveground storage

tanks . . . . . . . . . . . . . . . . . .

Underground storage

tanks . . . . . . . . . . . . . . . . . .

Hazardous waste . . . . . . . . .

Non-hazardous waste. . . . . .

Non-waste . . . . . . . . . . . . . . .

Containers

Hazardous waste . . . . . . . . .

Non-hazardous waste. . . . . .

Non-waste . . . . . . . . . . . . . . .

Open burning and detonation

sites . . . . . . . . . . . . . . . . . . .

Radioactive disposal sites . . . .

Category Ill

Pipelines

Hazardous waste . . . . . . . . .

Non-hazardous waste. . . . . .

16.6 -19.5

million

25,000

350,000

140,000

12,000

2,500

70

485

199

75,700

?

15-20,000

2,400

?

1,078

180,000

?

174

?

?

?

?

?

2,031

2.5 million

?

3,577

?

?

‘?

31’

?

700,000

miles

820-1,460

bgy

1-2 bgy

< 2 x < 2 x 800 bgy

>10 x > 10x 1.2 bgy

8.6 bgyd

?

525 bgy

<10 x

< 10x

<10 x

< 10x

?

<10 x 460 bgy

24.5 bgy < 10x

<10 x 0.3 mt

3-4 mty 4 mty

(dry)

0.10 bgyd

?

< 10x < 10x

<10 x

>10 x

< 10x

?

0.81 bgy < 10x >10 x 50 bgy d

40-140 mty (wet)

30 mty (wet)

138 mty

<10 x

?

< 2X

>10 x

‘?

>10 x

> 10x

< 2 x

>10 x

?

90 bgy

10 bgy

‘?

35.8 bgyd

1,800 bgye

580 mty

< 10x

< 2 x

?

< 10x

<10 x

< 2X

161 bgy

—

0.4 bgy

1,730 mty

700 mty

?

?

> 10x

< 2 x

< 10x

?

‘?

?

13.8 bgy

25 bg

7

< 10x

< 2 x

?

<10 x

<10 x

?

>10 x

?

?

>10 x

?

‘?

?

3.7 million

cubic yards

?

< 2 x

?

< 2X

?

280 bgye

?

< 10x

?

>10 x 250 bgy
Ch. 2—Groundwater Contamination and Its Impacts ● 5 3

Table 8.—Numbers of Sources and Amounts of Material Flowing Through or Stored in Sourcesa—continued

OTA Update 1977 Report

Possible Possible

Approximate Approximate uncertainty uncertainty Approximate

number of amount of in number in amount

Source

amount of

facilities materialb

estimatec

estimatec material

Category Ill—continued

Non-waste . . . . . . . . . . . . . . . 175,000 10 billion ? ? —

miles barrels

Materials transport and

transfer operations

Hazardous waste . . . . . . . .

16,000

spills

?

14 mty <10 x >10 x

50-60

million acres

280 million

acretreatments

229 million

acretreatments

169 million < 2 x < 2 x

acre-feet

0.26 mty < 2 x < 2X

active

ingredients

42 mty < 2 x < 2 x

Pesticide applications. . . . . .

Fertilizer applications. . . . . . . .

Animal feeding

operations . . . . . . . . . . . . .

De-icing salts

applications . . . . . . . . . . . .

Urban runoff . . . . . . . . . . . . . . .

8 mty < 2 x

?

< 2 x

< 10x

< 2 x

?

1,935

?

21.2-32.6

million acres

10-12 mty

‘?

Percolation of

atmospheric pollutants . . . .

Mining and mine drainage

Surface . . . . . . . . . . . . . . . . .

NA

4 million

acres; \

? ?

15,000 active

< 10x < 10x 108 billion

Underground . . . . . . . . . . . . . 67,000 gallons

inactive

0.36-1.0

mty acid \

Category V

Production wells

Oil wells . . . . . . . . . . . . . . . . 548,000 activity

2 million

abandoned

g <10 x < 10x

Geothermal, heat

recovery. . . . . . . . . . . . . . .

Water supply. . . . . . . . . . . . .

Other wells (non-waste)

Monitoring . . . . . . . . . . . . . .

Exploration . . . . . . . . . . . . . .

Construction excavation . . . . .

Category VI

Groundwater-surface

water interactions . . . . . . .

Natural leaching . . . . . . . . . . . .

Salt-water intrusion . . . . . . . . .

32 ? ? ? —

350,000 ? ? ? —
54 Ž Protecting the Nation’s Groundwater From Contamination

4.

they are best used to indicate the most numerous and most material-intensive sources.

Comparing estimates is difficult because they

are expressed in different units of measurement. The units cannot be converted into a

common base unit; thus only simple categorizations of large versus small numbers or

amounts can be made. (See the section on

Identifying Sources With “Significant” Potential To Contribute Substances to Groundwater, where this problem is encountered

again, for more details, )

Given these caveats, table 8 is still useful in at

least two ways:

1. It indicates sources which are numerous and/

or have large amounts of associated materials.

2. Table 8 shows that non-point sources (e.g.,

Category IV, including fertilizer and pesticide applications) and sources dealing with

non-waste products (e. g., Category II, including underground storage tanks) and with

non-hazardous wastes (e. g., Category 1, including brine disposal wells) are often as

important—in terms of numbers or amounts

of material as defined in table 7—as point

sources or hazardous waste sources. Many of

the non-point sources have associated with

them chemicals that are highly toxic (e. g.,

pesticide applications) or very diverse (e. g.,

underground storage tanks); see the previous

section on Association of Substances Found

in Groundwater With Sources).

Quantitative estimates of the numbers of sources

are available at least in part for 19 sources. The

contribution of some sources to groundwater contamination is difficult to measure (e. g., salt-water

intrusion), and data are incomplete for others. Of

equal importance, estimates of amounts do not exist

for 11 sources and are incomplete for seven others.

For some sources, amounts are technically difficult

to measure (e. g., drainage wells and residential disposal); for others, local information is available but

is difficult to compile on a national level (e. g., nonwaste containers and water supply wells). With increased time and effort, investigators can probably improve estimates for some sources (e. g., industrial subsurface percolation and hazardous waste

containers) and possibly obtain sufficient information to generate first estimates for some of the

sources for which there are no estimates (e. g., spray

irrigation).

The most numerous sources include: subsurface

percolation (domestic), injection wells (brine disposal and drainage), industrial landfills, surface impoundments, underground storage tanks, pipelines,

irrigation practices, pesticide applications, fertilizer

applications, mine drainage, and oil wells.

The largest amounts of material apparently flow

through or are stored in the following sources: subsurface percolation (domestic), brine disposal wells,

industrial and municipal landfills, surface impoundments, waste tailings and piles, materials stockpiles,

and pipelines. Much of the material that enters

groundwater comes from non-point sources, such

as applications of pesticides and fertilizers, especially in particular regions of the country. Nonwaste sources such as injection wells, storage tanks,

and many agricultural activities, and non-hazardous waste, and/or non-waste sources contribute large amounts of material.

Photo credit: Paula Stone, Office of Technology Assessment

Of an estimated 2.4 million steel underground storage

tanks in the United States, as many as one-fourth may

be used by farmers; other important users include

service stations (using an estimated 50 percent) and

government agencies (using an estimated 5-6 percent)

(see app. A.5).
Ch. 2—Groundwater Contamination and Its Impacts ● 5 5

POTENTIAL FOR SOURCES TO CONTRIBUTE

SUBSTANCES TO GROUNDWATER

Determining the contribution of any source to

groundwater contamination depends on understanding a broad range of technical, economic, and

social factors. Economic and social factors affect

where sources are located, how they are used, and

what they are used for. The actual contribution of

substances by any source will depend on such technical factors as biodegradation rates, surface and

subsurface hydrology (e. g., percolation and adsorption rates), the amount and type of wastes, release

patterns, number of sources, and source characteristics (condition, maintenance, and operation

procedures).

Two basic approaches are discussed below for

identifying which sources have the potential for contributing significant amounts of substances to

groundwater. One approach involves the use of

physical and mathematical models to predict when

and which sources release substances to groundwater and what happens to the substances once they

enter groundwater. This approach can also involve

record-keeping at individual facilities. In the second approach, descriptive criteria are developed in

order to generate lists of important sources (as

cl(’fined on the basis of those criteria).

Modeling the Potential of Sources

To Contaminate Groundwater

Efforts m protect groundwater would be aided

by a priori information on when an individual facility or activity will release substances with the potential to enter groundwater, and by estimates of

what portion of these substances will actually enter groundwater.

Little work has been done to develop measures

of the potential for sources to contribute substances

to groundwater-. In general, the site-specific nature

of hydrogeology and the varying characteristics of

individual sources have precluded development of

predictive models. One existing model for steel

underground storage tanks uses tank age and local

soil condition data to generate predictions about

the’ situations in which tanks will develop leaks

(Rogers, no date). If an inventory of underground

storage tanks (including specific age data) were

available, at-risk situations identified by the model

could be investigated. Apparently this type of modeling has not been developed for other sources and

is limited by data availability.

Physical and mathematical models are available

that predict the behavior and movement of substances once they enter groundwater. (See app. A.5

for references. ) Most of the models yield a temporally varying description of the spatial distribution of a substance in an aquifer (see ch. 5). Input

requirements generally relate to underlying soils

and other hydrogeologic features and the amount

or rate at which the aquifer is receiving the substance. If existing contamination and aquifer characteristics are known, some models can be run in

reverse to determine the amount of the substance

that must have been released from its source to produce the given conditions. These models rely on

empirical measurements for input; the value of their

output, therefore, is highly dependent on both the

underlying assumptions and the quality of the input data.

Measuring contamination potential thus also involves record-keeping at individual facilities. Losses

caused by leakage or infiltration of leachate can be

estimated via water balance, injected waste leakage,

or back-calculation procedures (University of Oklahoma, 1983). However, these procedures are basically empirical or bookkeeping for an individual

facility, and the information gained is used to estimate leachate generation or the amount of contaminated recharge at that particular facility. Applicability of these prediction methods to other similar

facilities is limited. Historic flow records could contribute to crude predictions, but the records are generally not available.

Identifying Sources With

‘‘Significant” Potential To Contribute

Substances to Groundwater

OTA’s analysis attempted to develop objective

criteria that could be used to identify and list im-
56 ● Protecting the Nation’s Groundwater From Contamination

portant sources, i.e., sources with a ‘‘significant

potential to contaminate groundwater. However,

in the course of developing these lists, a number

of problems became apparent that severely limited

the usefulness of the lists.

Developing a single unambiguous set of objective criteria is not a simple task. One investigator

might believe that amounts of material are a sufficient indicator of importance, and others might

be concerned with the diversity of substances associated with various sources. Groups of criteria

might be used, but the lists of important sources

will differ depending on which sets of criteria are

selected, as shown below.

An additional problem concerns comparisons of

different units of measurement for a single criterion.

For example, suppose that the amount of material

handled by a source is the criterion under consideration. In table 7, amounts of material are measured in gallons, tons, cubic yards, barrels, acres,

and acre-feet. Definition of a “large” versus

‘‘small” amount is arbitrary because of the inabilit y to make comparisons among different units of

measurement. In addition, documentation or estimation of large amounts of material (using any definition of large) does not necessarily mean that large

amounts of substances will be released into the

groundwater; estimates of large amounts should be

viewed only as upper bound indicators of the potential for contaminant release.

To illustrate some of the above problems and to

indicate the context in which such lists could be

used, listing is examined in detail. As an example,

one set of criteria was selected, comprised of four

characteristics described in the section on Factors

Influencing a Source’s Potential To Contaminate

Groundwater: number, amounts of material, diversity of substances, and pervasiveness. Although

these criteria might seem to be relatively objective,

all entail arbitrary definitions of low (or small),

moderate, and high (or large), The definitions thus

determine the evaluations made in any list.

Information is even more subjective or sparse for

other possible criteria, such as the degree to which

source control (of operating and maintenance procedures) is required to prevent the release of

substances, the potential of the source to introduce

new substances into groundwater, the toxicity of

associated substances, and the nature of release

characteristics. These criteria are useful in characterizing sources, but they are more difficult to

interpret when considering the question of the potential of any particular source to contaminate

groundwater. For example, the release of substances with any of the spatial or temporal release

patterns discussed above could result in little to significant contamination.

Using the above four criteria, several lists of

sources were generated by using different groupings of the criteria and different levels of importance for particular criteria (e. g., use of high numbers in one list, moderate to high numbers in

another list). A selection of these lists is presented

in table 9. Although some sources fit into many of

these lists, a major conclusion is that the exact listing

changes as different criteria are selected. For example, if regulatory authorities are interested in

groundwater contaminated by a high diversity of

substances, there are five important sources (subsurface percolation, landfills, open dumps, residential disposal, and surface impoundments) and, of

these, the most important source would be surface

impoundments (based on table 6). If the number

of facilities alone is important (e. g., as a gauge of

regulatory efforts required for control), nine sources

are of primary interest and, of these, the most important source would be subsurface percolation

(based on table 8).

Among the first nine lists in table 9, seven sources

appear on more than one-half the lists: subsurface

percolation, injection wells, landfills, open dumps,

surface impoundments, underground storage tanks,

and fertilizer application. Of all sources, only the

surface impoundment source is widespread and has

a ‘ ‘high” ranking for the other three criteria (see

table 7). Additional criteria could justify the inclusion of specific sources. For example, it is known

that a high percentage of underground storage tanks

are leaking gasoline and causing a number of contamination incidents (see app. A. 5). Location over

vulnerable aquifers (e. g., sole-source aquifers)

would be another reason for including surface impoundments and other sources on a list.

The first nine lists are based exclusively on the

above four criteria, which tend to be quantitative;

quantitative criteria will generally bias a list toward
Ch. 2—Groundwater Contamination and Its Impacts ● 5 7

I

x x

x x

x x

x

x

x

xx x

x x

x

x

x

x

x Xxx x x x

x

x

x

x

 

 

 

x

x

x

x

x

x

x

x

 

 

 

 
58 ● Protecting the Nation’s Groundwater From Contamination

point sources, because point sources are relatively

easy to identify and count or measure (note that

of the above seven sources, only fertilizer applications is a non-point source). In contrast, suppose

toxicity, a criterion that is more descriptive of the

potential health effects of substances and is not

biased toward point sources, is selected. Then the

list (see the toxicity column in table 9) would include pesticide applications, open dumps, residential disposal (e. g., TCE and other halogenated

aliphatic hydrocarbons), open dumps, and the facilities/activities of each source type that deal with

hazardous wastes. Although this list does focus on

hazardous waste sources, it also includes several

non-point sources (pesticide applications, residential disposal, land application, pipelines, and materials transport). Other criteria that could be used

in this manner include economic impacts and environmental impacts.

This exercise illustrates the difficulty in identifying one single list of sources that would satisfy

all sets of criteria—the list of sources generated depends on the criteria selected for identifying” important” sources. In addition, groundwater contamination problems differ from region to region

and from site to site, thereby making national lists

somewhat tenuous. Listing the sources is not as important as recognizing that materials flow through

society; that problems involve non-point, non-hazardous, and non-waste sources; that problems vary

from region to region; and that groundwater contamination is highly site-specific.

CHAPTER 2 REFERENCES

Congressional Research Service, Six Case Studies of

Compensation for Toxic Substances Pollution: Alabama, California, Michigan, Missouri, NewJersey,

and Texas, prepared for the Committee on Environment and Public Works, U.S. Senate, 1980b.

Coniglio, W., ‘‘Criteria and Standards Division Briefing on Occurrence/Exposure to Volatile Organic

Chemicals, ” Office of Drinking Water, U.S. Environmental Protection Agency, 1982.

Considine, D. M., and G. D. Considine (eds. ), Van

Nostrand’s Scientific Encyclopedia, 6th ed. (New

York: Van Nostrand Reinhold, 1983)

Council on Environmental Quality, “Contamination of

Ground Water by Toxic Organic Chemicals, ”

Washington, DC, 1981.

Environ Corp., “Approaches to the Assessment of

Health Impacts of Groundwater Contaminants, ”

draft report prepared for the Office of Technology

Assessment, August 1983.

Fryberger, J., “Rehabilitation of a Brine-Polluted

Aquifer, ” Office of Research and Monitoring, U.S.

Environmental Protection Agency, 1972.

Geraghty & Miller, Inc., “The Fundamentals of

Ground-water Quality Protection, ” New York,

1983.

Harris, R. H., ‘ ‘The Health Risks of Toxic Organic

Chemicals Found in Groundwater, ” Princeton

University/Center for Energy and Environmental

Studies, Report No. 153, 1983.
Ch. 2—Groundwater Contamination and Its Impacts ● 5 9

Harris, R. H., Center for Energy and Environmental

Studies, Princeton University, personal communication, January 1984.

Harris, R. H., J. V. Rodricks, R. K. Rhamy, and S.

S. Papadopulos, ‘ ‘Adverse Health Effects at a Tennessee Hazardous Waste Disposal Site, draft manuscript, Fourth Annual Symposium on Environmental Epidemiology, University of Pittsburgh, no date.

Hawley, G. G., The Condensed Chemical Dictionary,

9th ed. (New York: Van Nostrand Reinhold, 1977).

Kaplan, E. M. G., B. Royce, E. F. Riedel, and J.

Sathaye, ‘ ‘Assessment of Environmental Problems

Associated With Increased Enhanced Oil Recovery

in the United States: 1980 -2000,” Brookhaven

National Laboratory 51528 UC-92a, under U.S.

Department of Energy contract No. DE-AC02-

76CH00016, 1983.

Lewis, R. J., and R. L. Tatken (eds. ), Registry of Toxic

Effects of Chemical Substances, 1979 ed., U.S. Department of Health and Human Services (Washington, DC: U.S. Government Printing Office, September 1980).

Metropolitan Area Planning Council, “A Guide to the

Safe Use and Disposal of Hazardous Household

Products, Boston, MA, 1982.

Miller, D. W. (cd.), Waste Disposal Effects on Ground

Water (Berkeley, CA: Premier Press, 1980).

National Academy of Sciences, Drinking Water and

Health (Washington, DC: National Academy Press,

1977).

National Academy of Sciences, Risk Assessment in the

Federal Government: Managing the Process (Washington, DC: National Academy Press, 1983).

Natural Resources Defense Council, “Comments of the

Natural Resources Defense Council, Inc. on National

Revised Primary Water Regulations, Volatile Synthetic Organic Chemicals in Drinking Water, Advanced Notice of Proposed Rulemaking, 47 Federal

Register, 9350-9358 (Mar. 4, 1982), ” Sept. 30, 1982.

O’Brien, R. P., and J. L. Fisher, ‘ ‘There is an Answer

to Groundwater Contamination," WATER\Engineering and Management, p. 30ff, May 1983.

Odum, E. P., Fundamentals of Ecology, 3d ed. (Philadelphia: W. B. Saunders Co., 1971).

Orange County Water District, “Water Quality and

Consumer Costs, ” 1972.

Patterson, W. L., and R. F. Banker, “Effects of Highly

Mineralized Water on Household Plumbing and Appliances, ’ paper presented at the Annual Conference, American Water Works Association, June

1968.

Prichard, H. M., and T. F. Gesell, “Radon-222 in

Municipal Water Supplies in the Central United

States, Health Physics 45:991-993, 1983.

Radike, M. J., K. L. Stemmer, P. G. Grown, E. Larson, and E. Bingham, ‘ ‘Effect of Ethanol and Vinyl

Chloride on the Induction of Liver Tumors: Preliminary Report, Environmental Health Perspectives

21:153-155, 1977.

Raucher, R. L., ‘‘A Conceptual Framework for Measuring Benefits of Groundwater Protection, Water

Resources Research 19:320-326, 1983.

Reitman, F., “Costs and Benefits in Aquifer Protection, New England Journal, Business and Economics 19(1), 1982.

Ridgley, S. M., and D. V. Galvin, ‘ ‘Summary Report

of the Household Hazardous Waste Disposal Project , Toxicant Control Planning Section, Water

Quality Division, Municipality of Metropolitan Seattle, WA, 1982.

Rogers, W., ‘‘Tank Integrity Program, Warren Rogers Associates, Inc., Newport, RI, no date.

San Francisco Bay Regional Water Quality Control

Board, “Underground Tank Leak Detection Program Status Report, ’ 1983.

Science News, vol. 125, No. 104, Feb. 18, 1984.

Sharefkin, M. F., M. Schecter, and A. V. Kneese, “Impacts, Costs, and Techniques for Mitigation of Contaminated Groundwater, pp. 93-126 in Papers for

and a Summary of a Workshop on Groundwater Resources and Contamination in the United States

(Washington, DC: National Science Foundation,

PRA Report 83-12, August 1983).

Sheridan, D., “Desertification of the United States’

(Washington, DC: Council on Environmental Quality, 1981).

Southeast Michigan Council of Governments, “Public

Review Summary Draft: Genoa Township Policy

Plan for Groundwater Protection, March 1982.

Tucker, R. K., ‘‘Groundwater Quality in New Jersey:

An Investigation of Toxic Contaminants, New Jersey Office of Cancer and Toxic Substances Research,

1981.

U.S. Environmental Protection Agency, “Hazardous

Waste Disposal Damage Reports, ” No. 3, 1976.

U.S. Environmental Protection Agency, ‘ ‘The Report

to Congress; Waste Disposal Practices and Their Effects on Ground Water, ” 1977.

U.S. Environmental Protection Agency, “Ambient

Water Quality Criteria for Carbon Tetrachloride,

NTIS PB81-117376, 1980a.

U.S. Environmental Protection Agency, “Ambient
60 ● Protecting the Nation’s Groundwater From Contamination
Chapter 3

Federal Institutional Framework

To Protect Groundwater

From Contamination
contents

Chapter Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Relevance of Federal Statutes to Groundwater Protection . . . . . . . . . . . . . . . . . . . . . . .

Summary of Federal Statutes and Programs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Federal Legislation Passed Prior to the 1970s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

Environmental Legislation: 1969 to the Present . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Sources Addressed by Federal Statutes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Sources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Types of Programs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Water Quality Standards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Mechanisms for Interagency Coordination. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

USGS Coordinating Committees . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Program-Related Agreements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Water Data Coordination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Efforts To Improve Capabilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Financial Assistance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Technical Assistance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Federal Research and Development Concerning Groundwater Quality . . . . . . . . . . . . . . . . .

Chapter 3 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

TABLES

Table No.

10. Summary of Federal Programs and Ac

Groundwater Quality . . . . . . . . . . . . . .

11. Descriptions of Major Federal Statutes

ivities Related to the Protection of

. . . . . . . . . . . . . . . . . . . . . . ,. . . . . . . . . . . .

Relevant to the Protection of

Groundwater Quality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

12. Groundwater-Related Activities of Federal Agencies . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Page

63

64

64

64

73

75

75

77

80

81

82

82

83

83

83

84

84

86

Page

65

66

72

13. Relationship Between Sources of Contamination and Federal Statutes . . . . . . . . . . . . . . 76

14. Committees for Program Coordination Between USGS and Other Federal Agencies . 82

15. Federal Involvement in Groundwater Quality Research and Development . . . . . . . . . . 85
Chapter 3

Federal Institutional Framework To

Protect Groundwater From Contamination

CHAPTER OVERVIEW

OTA’s assessment of Federal activities regarding groundwater contamination involved examination of 16 Federal statutes and discussions with representatives of 11 Federal agencies. The laws and

programs selected for review relate to sources of

contamination, the regulation of potential contaminants, and the use of groundwater for drinking water supplies. This chapter provides a summary of the existing Federal laws and programs that

protect groundwater quality. In addition, aspects

of the laws and programs are analyzed that define

or support—and are thus shared in common by—

detection, correction, and prevention activities.

The following topics are included:

●

●

●

●

●

●

relevance of Federal laws to the protection of

groundwater;

summary of Federal laws and programs;

sources of contamination addressed by Federal laws;

water quality standards;

existing mechanisms for interagency coordination with respect to implementation of legislative mandates; and

efforts of the Federal Government to improve

its own capabilities and those of the States to

protect groundwater.

Federal detection, correction, and prevention activities are discussed in greater detail in chapters 6,

9, and 11, respectively.

The general conclusions drawn from this information follow.

There is no explicit, comprehensive national

legislative mandate to protect groundwater from

contamination. Federal laws and programs do not

address all sources known to contaminate groundwater, the vast majority of substances that have

already been found or have the potential to be found

in groundwater, or all uses of groundwater,

Specifically with respect to sources, different Federal laws and programs address different sources

of groundwater contamination in different ways.

The differences often have little relation to the potential for a source to cause contamination. In general, more stringent requirements are applied to

selected point sources (especially those associated

with hazardous wastes), rather than non-hazardous

waste, non-waste, and non-point sources.

The Federal approach to contaminants, in terms

of standards, is neither complete nor consistent.

(The Federal regulation of potential contaminants

for prevention is discussed in ch. 11.) Although

drinking is the principal use addressed by Federal

statutes, not all drinking water supplies are covered (see ch. 6).

There are many Federal laws and programs directed toward assisting the States and Federal agencies with groundwater contamination problems.

These generally provide for financial and technical assistance and research and development. Several laws also authorize the States to implement federally mandated programs and establish minimum

requirements for such programs. However, Federal efforts to protect groundwater quality are fragmented, and there is no single agency or organization responsible for all groundwater programs

and activities; several coordination mechanisms are

used.

63
64 . Protecting the Nation’s Groundwater From Contamination

RELEVANCE OF FEDERAL STATUTES TO

GROUNDWATER PROTECTION

Protection of groundwater is not covered comprehensively by any one Federal law; nor is one

Federal agency or office responsible for overseeing

or coordinating all groundwater programs and activities. 1 Although the groundwater protection strategy of the U.S. Environmental Protection Agency

acknowledges the need for comprehensive resource

management, the details of the strategy do not fully

provide for it (EPA, 1984).2

OTA’s analysis has identified 16 principal pieces

of Federal legislation that authorize numerous programs and activities relevant to groundwater protection, and it develops a framework for determining how current laws and programs contribute to

the detection, correction, and prevention of contamination. Groundwater protection per se is

not, however, the primary objective of any of the

statutes.

Table 10 summarizes the relationship between

Federal legislation and groundwater protection

activities including: detection/investigatory activities; corrective actions for contaminated groundwater; measures to prevent contamination; and

standards for contaminants used in detection, correction, and prevention activities. Although table

10 presents an extensive array of programs and

activities, Federal efforts overall are not fully protecting groundwater resources. For example, not

all sources of groundwater contamination are included, and for the general source types that are,

not all related facilities and/or activities may be covered; not all drinking water supplies are monitored

routinely; and standards have not been developed

for most contaminants that have already been detected in groundwater.

SUMMARY OF FEDERAL STATUTES AND PROGRAMS

Table 11 summarizes the objectives and major

provisions of the statutes examined in this study,

lists the Federal agencies responsible for their implementation, and indicates the relationship between the Federal laws and the States. (State programs are discussed in chs. 4, 7, 10, and 12. )

Additional Federal activities undertaken to support

or comply with these laws are summarized in table

12. Note that Federal statutes have not been ranked

in terms of their relative importance to groundwater

protection for many of the same reasons that sources

were not prioritized in chapter 2—i.e., ‘‘importance’ depends on the ranking criteria chosen and

site conditions.

Federal Legislation Passed Prior

to the 1970s

Early Federal legislation regarding water quality

in the United States focused primarily on surface

waters. These statutes were the precursors of the

more comprehensive water quality legislation

passed in the 1970s.
Ch. 3—Federal Institutional Framework To Protect Groundwater From Contamination ● 65

x x x x

x

x

x x x

x x x

. 

aj- : . . .

. . .

x

x

U

C

x

x

xx x x x

x

x

x

xx x x

x x

x

x

)

)
Table ll.— Descriptions of Major Federal Statutes Relevant to the Protection of Groundwater Quality

Objectives and provisions relevant

Statute to groundwater protection Responsible Federal agencies Relationship to the States

Atomic Energy Act

of 1954, 42 U.S.C.

2011a

Clean Water Act

of 1977, 33 U.S.C.

1251 -1378b

Coastal Zone

Management Act

of 1976, 16 U.S.C.

1451

One purpose of the act is to encourage the

development and use of atomic energy

for peaceful purposes consistent with the

common defense and security and the

health and safety of the public.

The act authorizes the regulation of the

development and utilization of atomic

energy, including the storage and disposal of radioactive wastes.

The objective of the statute is to restore

and maintain the physical, chemical, and

biological integrity of the Nation’s waters.

Activities authorized by the act include:

— the construction of sewage treatment

works and the use of alternative waste

management techniques (Section 201);

— the establishment of effluent standards

and the regulation of point discharges of

pollutants (Sections 302, 306, 307, and

402);

— the development of ambient water quality

criteria (Section 304);

— regulation of the disposal of dredged or

fill materials (Section 404);

— establishment of State or regional water

quality management plans, and the

establishment of a program to develop

Best Management Practices to control

non-point source pollution in rural areas

(Section 208);

— responses to oil discharges into navigable

water (Section 311).

One policy specified in the statute is to

preserve, protect, develop, and where

possible, restore or enhance the

resources of the Nation’s coastal zone

for this and succeeding generations.

The act authorizes funding to encourage and

assist the States in the development and

Department of Energy

Nuclear Regulatory Commission

Environmental Protection

Agency—Office of Radiation

Programs

Environmental Protection

Agency—Office of Water Programs Operations, Office of

Water Regulations and Standards, and Office of Water

Enforcement and Permits

Department of Agriculture—Soil

Conservation Service and Agricultural Stabilization and Conservation Service (Section 208)

Department of Transportation—

U.S. Coast Guard (Section 311)

Department of Commerce—

National Oceanic and

Atmospheric Administration

Regulation of certain radioactive materials is delegated by NRC to the States

that participate in the Agreement

States Program. Pursuant to the LowLevel Radioactive Waste Policy Act of

1980, States are currently engaged in

regional and individual planning efforts

to site new disposal facilities.

States (or local planning agencies) were

required by Section 208 to submit areawide water quality management plans

to EPA that identified and proposed

solutions to water quality problems (including point and non-point sources

affecting surface water and groundwater). Funding for Section 208 activities was terminated in 1981. Grants

under Sections 106 and 205(j) are now

being used to support planning

activities.

State (or interstate agency) grants are

authorized (Section 106) to assist with

the administration of water pollution

control activities required by the act.

Funds are also available from Sections

205(g) and (j) which are reserves from

State construction grant allotments.

While Section 205(g) funds are used

primarily to support construction grant

programs (for sewage treatment works),

Section 205(j) funds are authorized to

support State water quality management planning.

Regulatory authority for Section 402 is

delegated to States for the point discharges of pollutants into navigable

waters. c Section 303 requires States

to adopt water quality effluent standards for such discharges consistent

with Federal standards.

States are eligible to receive grants if a

coastal zone management program is

developed that meets minimum Federal

requirements.
Table 11 .—Descriptions of Major Federal Statutes Relevant to the Protection of Groundwater Quality—continued

Statute

Comprehensive

Environmental

Response,

Compensation,

and Liability Act

of 1980, 42 U.S.C.

9601

Federal Insecticide,

Fungicide, and

Rodent icicle Act,

as amended 7

U.S.C. 136e

Federal Land Policy

and Management

Act of 1976, 43

U.S.C. 1701, and

associated mining Iaws.g

implementation of management programs

with respect to the use of land and water

resources in the coastal zone, including

efforts to mitigate salt-water intrusion.

The statute does not contain an explicit

policy statement.

The act authorizes the Federal Government

to respond whenever there is a release or

threat of release of hazardous substances,

pollutants, or contaminants into the environment which may present an imminent

and substantial danger to public health

or welfare. Responses are financed by

excise taxes levied on petroleum and

chemical feedstocks. The act also establishes liability for the cost of response

actions on responsible parties and provides for compensation of expenses

incurred by the government.d

The statute does not contain an explicit

policy statement.

The act requires the registration of all

pesticides based on the submission of

specified data (Section 3), the classification of pesticides for general or

restricted uses (Section 3), and suspension and cancellation of pesticides

causing unreasonable adverse effects on

the environment (includes water, air, land,

plants, man and other animals, and their

interrelationships) (Section 6). The act also

requires the establishment of procedures

for the storage and disposal of pesticide

containers and excess pesticides (Section

19), as well as formulation of a National

Monitoring Plan for pesticides

(Section 20).

The statute specifies that it is the policy of

the United States that public lands be

managed in a manner that will protect the

quality of scientific, scenic, historical,

ecological, environmental, air and atmospheric, water resource, and archaeological values.

The act authorizes the regulation of the

use of public lands, including mining

operations.

Environmental Protection

Agency—Office of Emergency

and Remedial Response

Department of Transportation —

U.S. Coast Guard

Department of the Interior

Environmental Protection

Agency—Office of

Pesticide Programs

States may enter into a Cooperative

Agreement with EPA and assume lead

responsibiIity for remedial actions, or

States may enter into a contract with

EPA whereby EPA assumes lead

responsibility. In either case, States are

required to assure payment of 10 percent of the costs (or 50 percent if the

site is publicly owned), assume

responsibiIity for all future operation

and maintenance required at the site,

and assure the availability of an authorized hazardous waste disposal facility i

necessary for the disposal of wastes

removed during remedial activities.

Authority is delegated to States for

enforcement of FIFRA provisions (e.g.,

ensuring that pesticides are used in

compliance with any Federal restrictions) if States adopt and implement

adequate pesticide laws, regulations,

and enforcement procedures.f

States may also assume responsibility for

the training and certification of pesticide applicators if Federal approval of a

plan for such activities is obtained.

Federal funding of State programs is

available to those States that enter into

cooperative agreements with EPA.

Mining regulations may not preempt State

laws and regulations regarding the

conduct of mining operations or

reclamation on Federal lands. States

may enter into agreements with BLM

to provide for joint administration and

enforcement of regulatory programs
Table 11.- Descriptions of Major Federal Statutes Relevant to the Protection of Groundwater Quality—continued

Objectives and provisions relevant

Statute to groundwater protection Responsible Federal agencies Relationship to the States

Hazardous Liquid

Pipeline Safety

Act of 1979, 49

U.S.C. 2001

Hazardous

Materials Transportation Act of

1974, 49 U.S.C.

1801h 

National Environmental Policy

Act of 1969, 42

U.S.C. 4371

Reclamation Act

of 1902, 43 U.S.C.

390(b)

The statute does not contain an explicit

policy statement.

The act requires the establishment of

Federal regulations for the movement of

hazardous liquids by pipeline (and their

storage incidental to such movement) and

pipeline facilities in or affecting interstate

or foreign commerce; such regulations

must consider the extent to which they

contribute to public safety.

The policy underlying the statute is to

protect the Nation adequately against

the risks to life and property which are

inherent in the transportation of hazardous materials in commerce.

The act requires the establishment of

Federal regulations for the transportation of hazardous materials (including

hazardous wastes in commerce.

The purposes of the statute include: the

declaration of a national policy to encourage productive and enjoyable harmony

between people and the environment, and

the promotion of efforts to prevent

or eliminate damage to the environment

and biosphere and to stimulate human

health and welfare.

The act directs Federal agencies to utilize a

systematic, interdisciplinary approach in

planning and decisionmaking that may

have an impact on the environment and to

prepare environmental impact statements

for major Federal actions significantly

affecting the quality of the human environment.

The policy underlying the statute supports

the participation and cooperation of the

Federal Government with States and local

interests in developing water supplies for

domestic, municipal, industrial, and other

purposes.

Some projects funded under the act are for

the development of underground water

supplies that are contaminated due to

natural leaching (e.g., high salt concentrations) or human activities and thus require

treatment prior to use.

Department of Transportation—

Office of Pipeline Safety

Regulation

Department of Transportation—

Office of Hazardous Materials

Regulation

All Federal agenciesi

Department of the lnterior—

Bureau of Reclamation

Federal regulations do not apply to intrastate pipelines and associated facilities

for which there are applicable State

regulations, provided that the State

agency is certified annually by DOT.

State regulations that are inconsistent

with Federal requirements are preempted. Although there is not a formal

delegation of authority, States may

enter into cooperative agreements with

DOT to obtain technical and financial

assistance. States may also establish

requirements for certain activities not

addressed by Federal regulations (e.g.,

routing the transport of hazardous

materials).

States have opportunity to review and

comment on Federal actions under

this and other programs under intergovernmental review provisions

authorized by Executive Order 12372.

Water rights for reclamation projects

must be obtained through States’ water

rights systems.

States are involved in project planning

activities.
Table 11.— Descriptions of Major Federal Statutes Relevant to the Protection of Groundwater Quality—continued

Objectives and provisions relevant

Statute to groundwater protection Responsible Federal agencies Relationship to the States

Resource Conser- The objective of the statute is to promote

vation and the protection of health and the environRecovery Act of ment and to conserve valuable material

1976, 42 U.S.C. and energy resources.

690 Subtitle C of the act requires the establishment of regulations for hazardous

waste generators, transporters, and owners

or operators of facilities who treat, store,

or dispose of such wastes.

Subtitle D requires the establishment of

Federal guidelines for State solid waste

management plans.

Environmental Protection Regulatory authority for Subtitle C is

Agency—Office of Solid delegated to States that establish

Waste programs that incorporate minimum

Federal requirements. Programs may be

more stringent than Federal requirements. Financial assistance is authorized to the States for development

and implementation of such

programs.

Although Subtitle D of the act does not

mandate the development of State solid

waste plans, States are required to

meet certain minimum requirements to

Safe Drinking The statute does not contain an explicit Environmental Protection

Water Act of objective but is designed to assure that Agency—Office of

1974, 42 U.S.C. public water systems meet minimum Drinking Water

300f standards for the protection of public

health.

The act requires the establishment of contaminant standards for drinking water

(Part B), the establishment of regulations

for underground injection (Part C), and the

protection of sole source aquifers (Part C).

obtain EPA approval and qualify for -

Federal financial assistance. (Subtitle D

State grants have not been available in

1982 and 1983.)

States may assume primary enforcement

responsibility for public water systems

(PWS) to ensure compliance with

national drinking water regulations if

minimum Federal requirements are met.

States may establish standards that are

more stringent than Federal standards

and may also set standards for

substances not addressed by the

Federal regulations.

Regulatory authority for the Underground

Injection Control (UIC) Program is also

delegated to those States that establish

programs that incorporate minimum

Federal requirements. Programs may be

more stringent than Federal

requirements.

Financial assistance is authorized to

States for the development and implementation of both the PWS and UIC

programs.

States, municipalities, partnerships, associations, companies, corporations, or

individuals may petition EPA to designate a sole source aquifer. Once an

aquifer is so designated, any of these

parties may petition EPA to review the

potential of a project to contaminate

the aquifer and create a significant

hazard to public health.
Table 11 .—Descriptions of Major Federal Statutes Relevant to the Protection of Groundwater Quality-continued

Objectives and provisions relevant

Statute to groundwater protection Responsible Federal agencies Relationship to the States

Surface Mining

Control and

Reclamation Act

of 1977, 30 U.S.C.

1201

Toxic Substances

Control Act of

1976, 15 U.S.C.

2601

Toxic Substances

Control Act of

1976, 15 U.S.C.

2601 (continued)

Water Research

and Development

Act of 1978, 42

U.S.C. 7801

One purpose of the statute is to establish

a nationwide program to protect society

and the environment from the adverse

effects of surface coal mining operations.

The act requires the establishment of regulations for surface mining of coal (and the

surface effects of underground coal mining) and authorizes reclamation of

abandoned mine lands.

The primary purpose of the act is to assure

that chemical substances and mixtures do

not present an unreasonable risk of injury

to health or the environment.

The purpose of the statute is to stabilize and

control both inactive mill tailings in a safe

and environmentally sound manner and to

minimize or eliminate radiation hazards to

the public.

The act requires the establishment of regulations for mill tailings at uranium or

thorium processing mills and authorizes

remedial actions at inactive sites.

The purpose of the statute is to assist the

Nation and the States through water

resources science and technology to

address a variety of water quality and

quantity concerns.

The act authorizes the establishment

of a water resources research and techDepartment of the lnterior—

Office of Surface Mining

Department of Agriculture—

Soil Conservation Service

Environmental Protection

Agency—Office of Toxic

Substances

Department of Energy

Nuclear Regulatory Commission

Environmental Protection

Agency—Office of Radiation

Programs

Department of the Interior

Regulatory authority is delegated to

States that establish programs that

incorporate minimum Federal requirements. Financial assistance is authorized to States for the development and

implementation of such programs.

Grants are available for States to

establish programs to prevent or eliminate unreasonable risks to health or the

environment in association with

chemicals for which EPA is either

unable or unlikely to take action under

TSCA.

States may not establish or continue

requirements (e.g., testing requirements

or other regulatory actions) for

chemicals for which EPA has prescribed rules or orders unless they are

identical to the Federal requirements,

prohibit the use of the chemical, or are

adopted under the authority of other

Federal laws. Exemptions may be

approved by EPA under specified

circumstances.

Regulatory authority for active uranium

mills is delegated by NRC to the States

that participate in the Agreement

States Program.

States may enter into cooperative agreements with DOE for remedial action

projects; the agreements define the

responsibilities of the parties. States

are required to pay 10 percent of the

costs, concur with the remedial action

plan, and acquire private lands, as

necessary, to be used as a permanent

disposal site for residual radioactive

materials.

States are required to designate the

college or university at which the institute is established if there is more than

one land grant college within a State.

Two or more States may cooperate in

the establishment of a regional

institute.
Table 11 .—Descriptions of Major Federal Statutes Relevant to the Protection of Groundwater Quality—continued

I
72 • Protecting the Nation’s Groundwater From Contamination

Table 12.—Groundwater-Related Activities of Federal Agencies

Department of Agriculture—Agriculture Research Service:

ARS is conducting a limited number of research projects

related to groundwater recharge and the impacts of

agricultural activities on groundwater quality.

Department of Agriculture—Forest Service: The Forest

Service is conducting environmental research projects

on the fate and transport of pesticides (under the

National Agricultural Pesticide Impact Assessment

Program).

Department of Commerce— National Bureau of Standards:

NBS is responsible for projects regarding the

development of quality assurance standards that are

used by other Federal agencies (e.g., EPA and DOE) to

monitor the analytical performance of laboratories.

Department of Defense: The Army, Navy, and Air Force are

participating in a program to identify and evaluate

hazardous waste disposal sites on military installations

and to undertake remedial actions at certain sites to

control the migration of wastes (Installation Restoration

Program).

The Army Toxic and Hazardous Materials Agency

(USATHAMA), Air Force Occupational Environmental

Health Laboratory, Air Force Engineering and Service

Center, and Navy Energy and Environmental Support

Activity provide technical support for the Installation

Restoration Program and conduct research related to

these efforts.

The Army Medical Bioengineering Research and

Development Laboratory develops water quality criteria

for certain munitions compounds.

The Army Corps of Engineers is working with EPA

(under an interagency agreement) on design and

construct ion of remedial action projects for

CERCLA-designated sites. Research projects are also

being conducted to support these activities.

Environmental Protection Agency-Office of Research and

Development: EPA’s Environmental Photographic

Interpretation Center in Warrenton, VA, is responsible for

acquiring and interpreting overhead imagery to support

programs of EPA as well as other Federal agencies.

Activities include conducting inventories of abandoned

wells, mines, and hazardous waste sites, identifying

failures in septic tank systems, and supporting

emergency (e.g., oil spills) response activities.

EPA’s Environmental Monitoring Systems Laboratory in Las Vegas, NV, the Robert S. Kerr Environmental Research Laboratory in Ada, OK, and the

Environmental Research Laboratory in Athens, GA are

conducting studies related to prediction (e.g., studies of

those characteristics of aquifers that influence

contaminant behavior) and monitoring (e.g., protocols for

designing groundwater sampling programs). Other

research activities related to source control, health

effects, and treatment technologies are also being

conducted at other EPA facilities.a

Department of Energy: Programs have been established for

identifying and decommissioning nuclear materials

storage and processing facilities that have become

contaminated. Hydrogeologic investigations are being

conducted at some of these sites. These programs

include the Formally Utilized Sites Remedial Action

Program and the Surplus Facilities Management

Program.

Department of Housing and Urban Development:

Environmental assessments are conducted related to

housing projects; groundwater impacts are considered.

Department of the Interior—Bureau of Land Manage”

ment: BLM is conducting inventories of hazardous waste

sites on public lands.

Department of the Interior—National Park Service:

Groundwater monitoring studies are conducted at

various national parks to develop baseline data and to

determine the extent and impacts of groundwater

contamination from sources such as septic tanks and

agricultural activities.

Department of the Interior—U.S. Geological Survey: The

Water Resources Division of USGS is responsible for

collection and analysis of hydrogeologic information

(including groundwater data), maintaining computerized

data bases, conducting research, and coordinating

Federal activities with respect to the use and acquisition

of water data.

Department of the lnterior— Fish and Wildlife Service: FWS

is conducting inventories of hazardous waste sites for

all FWS lands and facilities.

Department of the lnterior— Bureau of Indian Affairs: BIA

is planning to conduct inventories of hazardous waste

sites on or near Indian reservations.

National Science Foundation: The Division of Civil and

Environmental Engineering, Directorate for Engineering

(the Hydraulics, Hydrology, and Water Resources

Program, and the Environmental and Water Quality

Engineering Program) supports research projects on

topics such as subsurface transport and wastewater

treatment. Policy-related research is conducted by the

Division of Research and Analysis, Directorate for

Scientific, Technological and International Affairs.

Nuclear Regulatory Commission: Research projects are

conducted related to the fate and transport of radioactive

substances in support of regulatory activities.

aEPA also supports several other types of activities related to groundwater. For example, EPA established a consortium called the National Center for Ground Water

Research in September 1979. The consortium consists of the University of Oklahoma, Oklahoma State University, and Rice University; and the Ground Water Research

Branch of the Kerr Laboratory serves as the center’s immediate technical liaison. The primary objective of the center is to identify long-term problems and needs

related to groundwater quality protection (e. g., transport and fate of contaminants and subsurface characterization) (Canter, 1982). EPA also provides funding to the

GroundWater Clearinghouse at the Holcomb Research institute. The clearinghouse contains an extensive file of groundwater models and assists the States in model

selection and application (see OTA, 1982).

SOURCE Office of Technology Assessment.
Ch. 3—Federal Institutional Framework To Protect Groundwater From Contamination ● 7 3

past 10 years for storage and disposal of radioactive substances.

Environmental Legislation:

1969 to the Present

The National Environmental Policy Act of 1969

(NEPA) was the first of many laws specifically enacted to protect the environment. It establishes a

national policy on environmental quality and directs

Federal agencies to use a systematic and interdisciplinary approach in decisionmaking and planning

to ensure that environmental concerns are sufficiently considered. The act also requires Federal

agencies to prepare environmental impact statements (EISs) for major Federal actions significantly

affecting the environment. Although NEPA does

not directly address groundwater, the EIS process

provides a mechanism for evaluating the impacts

of proposed projects (e. g., construction of a sewage

treatment plant) and regulatory programs on

groundwater.

Other environmental legislation passed in the

early 1970s contains explicit wording for the protection of air, water, and oceans. G The objective

of the Federal Water Pollution Control Act Amendments of 1972 (referred to as the Clean Water Act,

CWA) is “to restore and maintain the chemical,

physical, and biological integrity of the Nation’s

waters. 7 However, because of ambiguous language contained in key regulatory provisions of the

statute and conflicting judicial interpretations,8 its

%ee the Federal Water Pollution Control Act Amendments of 1972,

33 U,S.C. 1251 et seq., as amended by the Clean Water Act of 1977;

the Clean Air Act of 1970, 42 U. S.C. 1857 et seq., as amended; and

the Marine Protection Research and Sanctuaries Act of 1972, 33

U.S.C. 1401 et seq., as amended.

‘Section 10 1(a).

8

Section 402 of the act establishes the National Pollutant Discharge

Elimination System (NPDES), which requires that all point discharges

into ‘‘navigable waters’ be permitted. The legislative history of the

statute suggests that the NPDES program is limited to surface water

discharges. The permit program established by EPA is limited to surface water discharges. Federal courts have complicated the interpretation of the applicability of Section 402 to groundwater. The Seventh

Circuit upheld EPA’s authority to regulate underground discharges

(United States Steel Corp. v. Train, 556 F. 2d 822, 7th Cir., 1977);

two other courts denied EPA such authority (United States v. GAF

Corp., 389 F. Supp. 1379, S, D, Tex., 1975, and Exxon Corp. v,

Train, 554 F. 2d 1310, 5th Cir., 1977).

Section 303 of the act authorizes establishment of State water quality

standards. Although the language used in Section 303 does not mention groundwater standards explicitly, one court has upheld the author-
74 ● Protecting the Nation’s Groundwater From Contamination

application to groundwater has been limited. Nonetheless, provisions of the act are directly relevant

to groundwater: Sections 208, 205(j), and 106 provide authorization and funding for State and regional monitoring and planning activities directed

at both surface water and groundwater; Sections

201 and 311 authorize programs related to potential sources of groundwater contamination (land application of sewage treatment wastes and facilities

used to store large quantities of oil, respectively);

and Section 304 provides for development of water

quality criteria.

In 1974, Congress enacted the Safe Drinking

Water Act (SDWA) to “assure that water supply

systems serving the public meet minimum national

standards for protection of public health’ (U.S.

House of Representatives, 1974). To accomplish

this goal, the act authorizes development and enforcement of drinking water standards for contaminants that may adversely affect human health, establishment of a program to regulate underground

injection activities to protect drinking water sup-

.—-— —

ity of EPA to require States to develop such standards in cases where

a ‘ ‘clear hydrologic nexus’ can be shown between surface water and

groundwater (Kentucky ex rel. Hancock v. Train, 6 ELR 20689, E.

D. Ky,, 1976). For a more detailed discussion, see Wilson, 1976; Comments, 1978; and Tripp, et al. , 1979.

plies, and designation of sole-source aquifers to protect aquifer recharge areas. The act does not establish a comprehensive program for protection of all

groundwater resources.

Subsequent legislation, enacted between 1976

and 1980, authorizes preventive measures (e. g., design and operating requirements) and federally

funded remedial action programs for specific

sources of groundwater contamination. These statutes include: the Resource Conservation and Recovery Act (RCRA), the Surface Mining Control

and Reclamation Act (SMCRA), the Uranium Mill

Tailings Radiation Control Act (UMTRCA),

the Hazardous Materials Transportation Act

(HMTA), the Hazardous Liquid Pipeline Safety

Act (HLPSA), and the Comprehensive Environmental Response, Compensation, and Liability Act

(CERCLA, commonly known as “Superfund”).

The objectives or purposes of these statutes focus

more generally on protection of public health and

the environment than on protection of groundwater

per se; and the regulatory programs that followed

are inconsistent regarding groundwater protection

(see chs. 6, 9, and 11).

In addition to source-oriented statutes, two others

regulate the production and use of pesticides and

Photo credit:

FIFRA addresses the improper storage and disposal of pesticides and

State of Florida Department of Environmental Regulation

pesticide containers and residues.
Ch. 3—Federal Institutional Framework To Protect Groundwater From Contamination ● 75

other chemical substances. The Federal Insecticide,

Fungicide, and Rodenticide Act (FIFRA) provides

for registration and classification of pesticides (e. g.,

pesticides that may have unreasonable adverse environmental effects can be classified for ‘ ‘restricted

use’ in specified areas) and authorizes development

of procedures for storage and disposal of pesticides

and pesticide containers and residues. The Toxic

Substances Control Act (TSCA) authorizes the regulation of chemical substances or mixtures that may

present an unreasonable risk of injury to human

health and the environment. Regulations regarding the manufacture, processing, distribution in

commerce, use, or disposal can be promulgated.

To date, however, the application of these two

statutes to groundwater has been limited.

Three additional statutes relate to groundwater

protection. Two of them focus on natural resources

management. The Coastal Zone Management Act

of 1972 (CZMA) provides Federal funds to States

for development and implementation of management programs for coastal areas. Some State management programs are concerned with salt-water

intrusion, a source of groundwater contamination.

The Federal Land Policy and Management Act

of 1976 (FLPMA) authorizes the Bureau of Land

Management (BLM) to manage public lands on

the basis of multiple use and sustained yield principles. Although the act does not discuss groundwater explicitly, it does authorize the management

of public lands in a manner that protects the quality

of ecological, environmental, and water resource

values. The statute provides BLM with explicit authority to regulate the use and development of public lands through permits, leases, licenses, published

rules, and other instruments. g One use of public

lands with the potential to contaminate groundwater is mining.

The Water Research and Development Act of

1978 (WRDA)11 authorizes the establishment of

State Water Resources Research Institutes to conduct research and development relating to water

resources, to disseminate information about these

efforts, and to train scientists and engineers. Numerous projects funded under this program relate

to groundwater quality.

943 U. S.C. 1732.

Ioprior t. the passage of FLPMA, BLM had established or proposed regulations governing certain activities on Federal lands under

the authority of several mining laws, including the U. S, Mining Laws

of the 1860s and 1870s, the Mineral Leasing Act of 1920, and the

Materials Act of 1947. With the enactment of FLPMA and the reallocation of responsibilities for mining operations (among DOI’S BLM,

USGS, Minerals Management Service, and Conservation Division),

BLM initiated efforts to revise the existing regulations so that they

more clearly conformed with the objectives of the new legislation. Requirements for mining activities on Federal lands discussed in subsequent chapters reflect these changes; note that regulations for the

Geothermal Steam Act were redesignated, with minor revisions, in

43 CFR 3260 on Sept. 30, 1983.

The U.S Mining Laws (see 30 U.S.C. 22 et seq. ) include the Lode

Law of July 26, 1866 (14 Stat. 251), the Placer Law of July 9, 1870

(16 Stat. 217), and the Mining Law of May 10, 1872 (17 Stat. 91),

as amended. These laws address all ‘ ‘locatable’ mineral deposits such

as gold, silver, uranium, lead, iron, and copper. The Mineral Leasing Act of 1920 (30 U.S. C. 181) and the Materials Act of 1947 (30

U.S. C. 601) address “leasable” minerals, including coal, phosphate,

sodium, potassium, sand, gravel, and clay,

The Minerals Leasing Act and 16 other laws, Attorney General’s

Opinions, and Secretary’s Orders address onshore oil and gas operations. Regulations for oil and gas production have been undergoing

substantive revisions and were not analyzed in detail as part of this

study. See table 11, footnote g, for a brief description of the relationsip between the revised regulations and ground water.

1 I section 410 of the act repe~ed the Water Resources Research Act

of 1964 (Public Law 88-379, 78 Stat. 329, 42 U. S.C. 1961 et seq.),

as amended, and the Saline Water Conversion Act of 1971 (Public

Law 92-60, 85 Stat. 159, 42 U.S. C. 1959 et seq.), as amended.

SOURCES ADDRESSED BY FEDERAL STATUTES

This section focuses on current Federal programs

and activities to address specific sources of groundwater contamination. It reviews the sources covered by each statute and the types of programs that

each authorizes. Subsequent chapters describe in

detail Federal investigatory activities (including

monitoring), corrective actions, and preventive

measures for specific sources.

Sources

Table 13 summarizes the relationship between

sources known to contaminate groundwater and the

Federal statutes, (The table is organized according to the OTA source categories described in ch.

2; see table 5.) Two significant points about sources

and types of programs. based on table 13, are:
.——..——————

76 ● Protecting the Nation’s Groundwater From Contamination

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Ch. 3—Federal Institutional Framework To Protect Groundwater From Contamination ● 7 7

1.

2.

existing Federal statutes do not cover all

known sources of contamination discussed in

this study; and

sources are not treated in a uniform manner

by the programs authorized by Federal legislation.

Table 13 indicates that most sources (all but 4)

are covered by at least one statute and that 18

sources are covered by more than one statute. 12 But

the coverage is not as comprehensive as it appears

in the table. Most Federal statutes limit coverage

by defining only subsets of facilities and/or activities of a given source type that are subject to their

respective requirements. These definitions are

based on various criteria, such as the presence of

certain contaminants (e. g., hazardous wastes).

Moreover, the statutory definition of sources is

sometimes narrowed further by the regulations

issued by the Federal agencies responsible for implementing the statutes.13 Descriptions of the

sources covered by Federal programs is compiled

in appendix B. 1, which also indicates whether detection, correction, or prevention provisions have

been established for each source. These provisions

are discussed in chapters 6, 9, and 11, respectively.

Based on the information in appendix B. 1 and

the data on sources presented in chapter 2, a preIllt is impomant to point out that the applicability of CERCLA to

sources of contamination as presented in table 13 is based on the types

of sources currently on the National Priorities List. It is certainly possible to use CERCLA to cleat with other sources that release any hazardous substance, pollutant, or contaminant. Under CERCLA, hazardous substances are those designated by CWA (Sections 31 l(b)(2)(A)

and 307(a)); RCRA (Section 3001); CERCLA (Section 102); the Clean

Air Act (Section 112); and TSCA (Section 7). A pollutant or contaminant includes ‘ ‘any element, substance, compound, or mixture that will, or may reasonably be anticipated to cause death,

disease, behavioral abnormalities, cancer, genetic mutation,

physiological malfunctions, or physical deformations in organisms or

their offspring’ (Section lo). Petroleum (including crude oil

and any fraction thereo~ and natural gas, natural gas liquids, liquefied

natural gas, and synthetic gas usable for fuel are explicitly excluded

from the definition of hazardous wastes.

13 For example, Section 3001 of RCRA requires EPA to promulgate

regulations identifying the characteristics of hazardous wastes and listing particular wastes. The statute explicitly defines hazardous wastes

as solid wastes which may: ‘ ‘(A) cause, or significantly contribute to

an increase in mortality or an increase in serious irreversible, or incapacitating reversible illness; or (B) pose a substantial present or potential hazard to human health or the environment when improperly

treated, stored, transported, or disposed of, or otherwise managed

[42 U,S. C. 6903( S)].” The listing criteria developed by EPA (see 40

CFR 261) have been subject to much discussion and criticism in that

they limit the universe of hazardous wastes currently being regulated,

See OTA, 1983.

liminary list of sources of groundwater contamination which are not currently being addressed by

Federal statutes would include:

●

●

●

●

●

surface impoundments used to contain nonhazardous wastes (e. g., impoundments used

in agriculture);

waste piles and materials stockpiles used to

store non-hazardous wastes (except pesticides);

tanks (aboveground and underground) used

to contain non-hazardous wastes;

non-coal mining activities on private lands;

and

pipelines not regulated by the Hazardous Liquid Pipeline Safety Act.

Given the limitations of OTA’s information on

sources, this list should not be viewed as either exhaustive or rigid. Further, some States are addressing some of these sources. Thus, a thorough assessment of source coverage necessitates examination

of both Federal and State activities. (See ch. 4 for

a discussion of State coverage of sources. )

Types of Programs

In addition to the sources that are covered by

Federal statutes, it is also important to look at the

types of programs authorized by the laws (table 13).

These range from mandatory permit or licensing

programs to such voluntary programs as development of Best Management Practices for new or existing sources of contamination. Other programs

direct the Federal Government to undertake remedial action at inactive or abandoned sites that either

have contaminated or have the potential to contaminate groundwater.

The Federal Government’s general approach to

prevention and control of contamination from

sources with hazardous wastes and other toxic materials (e.g., mining operations and injection wells)

differs from the one used for most non-hazardous

waste sources (e. g., sanitary landfills in Category

H) and non-waste sources (e. g., agriculture-related

sources in Category IV and all sources in Category

14Five more sources not covered by Federal statute are: percolation of atmospheric pollutants, graveyards, animal burial grounds,

deicing salts, and household disposal. The OTA analysis in ch. 2 did

not identify these sources as major contributors to groundwater contamination nationwide.
VI). The major distinction is that the types of programs applicable to non-hazardous waste and nonwaste sources rely on use of voluntary design or

operating procedures (e. g., Best Management Practices), and those associated with hazardous or toxic

substances establish mandatory requirements (e. g.,

permit programs). Significantly, programs with

mandatory requirements focus on point sources of

contamination, and voluntary approaches are generally used with non-point sources.

The types of programs authorized by Federal

statutes that are relevant to sources of contamination can generally be described as follows (refer to

table 13):

●

●

●

Programs that establish mandatory requirements (e.g., design, operation, monitoring,

and/or corrective action requirements) for

sources of groundwater contamination: Tabl e

13 indicates that 11 statutes authorize development and enforcement of such requirements. Site-specific permits or licenses are required by several of these laws (i.e., Subtitle

C of the Resource Conservation and Recovery

Act, the Safe Drinking Water Act, the Surface Mining Control and Reclamation Act, the

Atomic Energy Act, and the Uranium Mill

Tailings Radiation Control Act). In addition,

some statutes specify that regulatory authority may be delegated to States that meet certain Federal criteria and/or enter into specific agreements with Federal agencies (table 10).

Programs that authorize Federal funding of

optional State programs for specific sources:

Subtitle D of the Resource Conservation and

Recovery Act is in this category. States are

awarded grants to develop solid waste management plans if the plans meet specified criteria for sanitary landfills.

Programs that establish Best Management

Practices (BMPs) or recommended procedures

for design and operation of certain sources:

Best Management Practices for certain nonpoint sources have been developed under the

Clean Water Act (e. g., agriculture-related

sources in Category IV). Procedures are recommended for the storage of pesticides and

disposal of pesticide residues under FIFRA

(e.g., some Category II sources).

Photo credit: U.S. Geological Survey

The storage and disposal of radioactive substances

is regulated under the Atomic Energy Act. This

photograph shows vaults used to contain low-level

radioactive wastes in shallow land burial sites.

Programs that establish Federal design and

operating criteria that must be met by owners

or operators in order to receive funds for specific projects (orproject components) that are

potential sources of contamination: This category includes the Innovative and Alternative

Technology provisions of Section 201 of the

Clean Water Act for land application of sludge

and wastewater from sewage treatment.

Programs that establish grant programs to

States for water planning and management activities: Under the Coastal Zone Management

Act, grants are awarded to States for development and implementation of coastal zone

management plans. Plans may provide for
Ch. 3—Federal Institutional Framework To Protect Groundwater From Contamination ● 7 9

minimizing impacts of salt-water intrusion by

controlling land and water uses. Section 208

of the Clean Water Act also provides for State

water planning and management activities.

Funds may be used at the State or local level

on non-point sources that cause groundwater

quality problems.

● programs that fund Federal remedial actions

for sources of groundwater contamination:

These statutes include the Comprehensive

Environmental Response, Compensation, and

Liability Act, the Surface Mining Control and

Reclamation Act, and the Uranium Mill Tailings Radiation Control Act. Some water development projects funded under the Reclamation Act also involve

contaminated groundwater.

Two statutes not included above

treatment of

are the National

Environmental Policy Act (NEPA) and the Water

Resources Development Act (WRDA). Although

NEPA is not directed at particular sources, environmental impact statements may be required for

federally funded projects that are potential sources

of groundwater contamination (e. g, construction

of a highway or housing development). WRDA also

does not address specific sources, but research projects funded under the act may relate to sources of

contamination.
—

80 ● Protecting the Nation’s Groundwater From Contamination

WATER QUALITY STANDARDS

Water quality standards specify the limits beyond

which substances in the environment may cause adverse impacts. Standards may be developed strictly

to protect public health, the environment, or uses

of groundwater, or to balance the benefits and costs

of achieving different levels of protection.

Water quality standards may be applied in programs to detect, correct, or prevent groundwater

contamination. Detection programs may use water

quality standards to determine whether there is a

problem that warrants action. For example, under

the Safe Drinking Water Act, public water supplies

are monitored for contaminants specified by the

National Interim Primary Drinking Water Regulations (NIPDWR); if concentrations exceed specified levels, certain steps must be taken, including

public notification. Under the Resource Conservation and Recovery Act, hazardous waste landfills must be monitored for particular substances;

if concentrations exceed specified levels, more intensive monitoring is required, possibly leading to

corrective action. Correction programs may use

water quality standards in determining cleanup

goals (e. g., under RCRA, the NIPDWR may be

used to set cleanup requirements; in the absence

of drinking water standards, background levels or

an alternative concentration limit may be used on

a case-by-case basis). Prevention programs may use

water quality standards in defining unacceptable

levels of contamination (e. g., under the Clean

Water Act, NIPDWR may be used to limit discharges to groundwater from the land application

of wastewater, depending on the use of the groundwater).

In addition to standards that relate correction or

prevention programs to the actual quality of water

that may result from a particular activity, technology-based approaches such as design and operating requirements are also often used. In 1972, with

passage of new water quality legislation, the Federal Government de-emphasized quality-based pollution control, given the difficulties in linking

allowable releases of pollutants from point sources

to the quality of surface waters.15

~

~For a more detailed discussion of the legislative history of the Federal transition to technology-based standards with respect to surface

water, see Copeland, 1983; and Davis, et al., 1976.

Federal statutes require standards for drinking

and surface water quality, but not specifically for

groundwater (see also the section Concentration

and Frequency Data in Relation to Government

Standards, ch. 2). For drinking water, there are

22 Federal mandatory minimum standards for public drinking water supplies under the Safe Drinking Water Act National Interim Primary Drinking

Water Regulations (Maximum Contaminant Levels, MCLs). Federal minimum standards are not

set for surface water quality; rather, the Federal

Government provides general guidance to the

States on setting standards for specific water uses

through Ambient Water Quality Criteria under the

Clean Water Act. These criteria include numeric

and narrative water quality standards to protect

public health and welfare, aquatic life, and recreational use. If a State does not adopt as a minimum

the NIPDWR or federally approved surface water

quality standards, the the Federal Government is

authorized to assume responsibilities for standards

in the State.

The Federal Government also provides guidance

on standards for selected substances in drinking

water through National Secondary Drinking Water

Regulations and Recommended Maximum Contaminant levels (RMCLs) under the Safe Drinking Water Act and Health Advisories (formerly,

Suggested No Adverse Response Levels, SNARLS).

National Secondary Drinking Water Regulations

cover selected contaminants and concentrations that

may adversely affect either odor, appearance, or

the public welfare. RMCLs are non-enforceable

health goals for public water supplies and are set

at levels that would result in no known or anticipated health effects, including an adequate

margin of safety. 16 Health Advisories cover selected

contaminants found in drinking water for which

there are no Federal requirements.

As shown in appendix C.3, which lists the specific substances covered by Federal and/or State

l~The first RMCLS were proposed for nine volatfle synthetic organic

chemicals (VOCS) in the Federal Register on June 12, 1984. MCLS

for these chemicals will be proposed when the RMCLS are finalized.

MCLS are to be set as close to the RMCLS as feasible but will also

be based on a balancing of health protection with other factors including the availability and costs of treatment technologies.
Ch. 3—Federal Institutional Framework To Protect Groundwater From Contamination ● 8 1

Photo credits” State of Florida Department of Environmental Regulation

An underground source of drinking water is in part defined under the Safe Drinking Water Act as containing fewer than

10,000 milligrams per liter (mg/1) of total dissolved solids (TDS) (left). Good tasting water has less than 1,500 mg/1 of TDS (right).

water quality programs, different programs gen- concerns as well as technology-related and economic

erally apply to different substances. When a factors, while Ambient Water Quality Criteria consubstance is covered by more than one program, sider only health or environmental impacts. Furminimum requirements or suggested concentra- ther, health information from Ambient Water

tions differ from program to program. Such dif- Quality Criteria includes the ingestion of aquatic

ferences arise because concentrations developed life and not just adverse impacts from drinking

under the Safe Drinking Water Act reflect health water.

MECHANISMS FOR INTERAGENCY COORDINATION

The multiplicity of both groundwater-related coordinating all groundwater programs and activlaws and the agencies responsible for their imple- ities, three mechanisms for interagency coordinamentation has fragmented Federal protection of tion are used and are described below. Activities

groundwater quality. Further, within certain agen- to be coordinated are both regulatory, primarily

cies, numerous offices are responsible for ground- focusing on sources of contamination, and non-regwater activities (refer to tables 11 and 12). Because ulatory, including data collection, technical assistno single agency or organization is responsible for ance, and research and development.
82 Ž Protecting the Nation’s Groundwater From Contamination

USGS Coordinating Committees

The U.S. Geological Survey and other Federal

agencies have entered into Interagency Agreements

(IAGs) or Memoranda of Understanding (MOUs),

which establish coordinating committees comprised

of representatives of each agency. The committees

coordinate plans and activities of mutual interest,

including water-related issues (e. g., hydrologic investigations), and exchange data and information.

Table 14 lists the agencies with which USGS has

established committees, their effective dates, and

their purposes. As table 14 indicates, the scope of

these committees extends beyond groundwater-related issues. Nonetheless, the committees provide

a forum for raising groundwater concerns and have

led to additional agreements that focus on groundwater quality.

Program-Related Agreements

IAGs and MOUs established between Federal

agencies also relate to implementation of statutespecific programs or activities concerning groundwater protection, such as provision of technical assistance for hydrogeologic investigations (e. g.,

groundwater monitoring) or for corrective actions.

Several agreements described below are examples

of the types of programs that have been arranged:

● The Environmental Protection Agency and the

Army Corps of Engineers have entered into

an agreement whereby the Corps provides

both management and technical assistance to

EPA with respect to implementation of the

Comprehensive Environmental Response,

Compensation, and Liability Act (CERCLA).

Table 14.—Committees for Program Coordination Between USGS and Other Federal Agencies

Federal agency Effective date Purpose

Department of Agriculture—

Soil Conservation Service

Department of Commerce—

National Oceanic and

Atmospheric Administration

Department of Energy—

Office of Energy Research

Department of the lnterior—

Bureau of Land Management

Department of the lnterior—

Bureau of Mines

Department of the lnterior—

Bureau of Reclamation

Department of the lnterior–

Office of Surface Mining

Environmental Protection

Agency

5/12/73, revised

1/21/76

2/20/72

11/8/78

3/6/74, revised

9/9/82

12/9/77

4/15/83

7/26/78

8/5/81

To exchange data and information, to cooperate in programs, and to

coordinate fields of operation such as geologic, soil, chemistry,

mineralogic erosion, watershed, river basin, flood, land resources,

wetland, hydrologic, sediment, snow, topographic surveys, and

mapping and resource analysis.

To coordinate related programs including seismology, marine geology

and geophysics, hydrology, mapping, and earth resource surveys from

space.

To develop an exchange of information on research, to resolve issues of

policy and responsibilities, to arrange cooperation in operation of

programs, and to exchange budget information for cooperative

programs.

To coordinate related programs including lease management,

environmental studies, land and resource classification, mapping and

surveys, and water resource investigations.

To clarify the primary roles of the agencies and to establish mechanisms

for coordination, including resource classification, data storage, and

data standards.

To coordinate related programs including mapping, land and water

resource planning, water resources investigations and research,

geologic investigations and research, and information systems.

To coordinate data exchanges and related programs, including

monitoring, hydrologic studies, land use, geologic mapping, data

systems, and programs and budgets.

To provide a mechanism to coordinate programs and plans, provide for

technology transfer and data exchanges, arrange for cooperation and

support of programs of mutual interest, arrange exchange of budget

and planning information, act as a clearinghouse for EPA/USGS

contacts, and provide information on existing and future MOUs and

IAGs between the agencies.

SOURCE: USGS, 1983
Ch. 3—Federal Institutional Framework To Protect Groundwater From Contamination ● 83

Under the agreement, the Corps is responsible for managing the design, construction, and

operation of remedial actions at hazardous

waste sites for which EPA (as opposed to a

State) assumes lead responsibility.

● An agreement between EPA and USGS specifies the cooperation and extent of assistance

that USGS will provide EPA’s Office of Waste

Programs Enforcement in gathering information and assessing the hydrology and geology

of hazardous waste sites. The types of assistance that USGS can provide include but are

not limited to: provision of data from USGS

files on groundwater systems near a hazardous waste site; technical assistance on the design or review of investigative studies; and

comments on remedial action designs and the

predicted effectiveness of such actions.

● Another agreement between EPA and USGS

is for USGS assistance to EPA in fulfilling its

responsibility to designate sole source aquifers

under Section 1424(e) of the Safe Drinking

Water Act. USGS provides EPA with the following: aquifer descriptions, evaluations of

aquifer vulnerability to contamination, background information on drinking water sources

and alternative water supply sources, and projections of water consumption,

Water Data Coordination

A 1964 directive issued by the Office of Management and Budget, Circular No. A-67, prescribes

guidelines for ‘‘coordination of Federal activities

in acquiring water data from streams, lakes, reservoirs, estuaries, and groundwater. The Department of the Interior was assigned lead responsibility. In October 1964, the Office of Water Data

Coordination was established within the Water Resources Division of USGS to implement provisions

of the directive. Two advisory committees, the Interagency Advisory Committee on Water Data and

the Advisory Committee on Water Data for Public Use, were also established to assist USGS.

EFFORTS TO IMPROVE CAPABILITIES

Improving Federal and State capabilities to protect groundwater quality requires a variety of activities, including financial assistance, technical assistance, and research and development. The following

discussions generally describe Federal activities and

programs in these areas.

Financial

A number of Federal

Assistance

statutes examined in this

study authorize grant programs for the States. None

of the provisions, however, is earmarked exclusively

for groundwater activities.

As indicated in table 11, the States maybe delegated authority to implement certain regulatory

programs, and grants are provided for these purposes. For example, Subtitle C of the Resource

Conservation and Recovery Act, the Surface Mining Control and Reclamation Act, and the Underground Injection Control (UIC) Program of the

Safe Drinking Water Act have such provisions.

Funds under these programs are not limited to

groundwater-related activities.

Under other statutes, the States are awarded

grants for planning and other water-related activities. For example, Section 208 of the Clean Water

Act authorizes the States or regional planning agencies to prepare water quality management plans to

identify and propose solutions to water quality

problems; the plans, however, are not legally binding. Section 208 was designed explicitly to address

non-point sources such as agriculturally and silviculturally related sources (e. g., irrigation return

flows), mine-related sources, construction activities, and salt-water intrusion.

17 Funding for Section 208 activities ended in 1981, but additional

funding for State water quality activities is now

available through Sections 106 and 205(j) of the

Clean Water Act. Funding for other programs

(e.g., the Coastal Zone Management Act, RCRA

17sectirjn 208(b)(2)(F)—(K)
84 ● protecting the Nation’s Groundwater From Contamination

Subtitle D, and the Rural Abandoned Mine Program) has either been reduced or eliminated in recent years.

Technical Assistance

Programs within EPA, USGS, and the Soil Conservation Service (SCS) provide technical assistance

on groundwater quality to the States, individuals,

and other Federal agencies. For example, EPA’s

Office of Drinking Water advises the States and

other authorities in determining the types of response appropriate to contamination incidents,

Health Advisories for 22 contaminants have been

developed; they suggest the level of a potential contaminant in drinking water at which adverse health

effects would not be anticipated for the most sensitive members of the population. Other kinds of

technical assistance activities at EPA include preparation of special guidance manuals for EPA program implementation (e. g., RCRA permit writer

manuals) and guidance on laboratory testing.

USGS technical assistance to the States and other

Federal agencies includes a variety of programs

(e. g., the Hazardous-Waste Hydrology Program,

the Assistance to Other Federal Agencies Program,

and the State Cooperative Program) (Chase, et al.,

1983). USGS assists in the development of both

Federal and State regulations and standards for

managing disposal of hazardous wastes and assists

Federal agencies on toxic waste cleanup under

RCRA and CERCLA programs. Through the National Water-Data Storage and Retrieval System

(WATSTORE) and National Water Data Exchange (NAWDEX), USGS maintains and provides access to data on surface water and groundwater quality and quantity and to meteorological

data. USGS study and research results are disseminated through numerous publications. USGS also

provides training programs for Federal, State, and

local agencies on hydrologic investigations. (Ch.

6 describes selected USGS activities in more detail.)

Although SCS programs are not directed specifically at groundwater, technical assistance to the

States, counties, and individuals is provided

through the Rural Clean Water Program and the

development of Best Management Practices to minimize adverse impacts on water quality. Financial

assistance to individuals may be provided through

the Agricultural Stabilization and Conservation

Service (ASCS) to implement some Best Management Practices.

In compliance with Section 104 of CERCLA, the

Agency for Toxic Substances and Disease Registry

was established as part of the Centers for Disease

Control (CDC) in April 1983.18 CDC is currently

working with the National Governors’ Association

(NGA) to implement Section 104(i)(3). Under the

section, the Agency for Toxic Substances and Disease Registry is required to maintain a complete

list of areas closed to the public or otherwise restricted in use because of toxic substance contamination. A Memorandum of Understanding is currently being negotiated between CDC and EPA on

the responsibilities of each for administering provisions of Section 104. CDC has also designated

public health advisors in EPA’s regional offices to

assist in assessing health impacts at uncontrolled

hazardous waste sites.

Other Federal agencies also have designated responsibilities under Section 104:

1.

2.

3.

The Food and Drug Administration conducts

field investigations and analyses of food chain

crops affected by CERCLA sites (Section

lo) .

The National Library of Medicine is conducting an inventory of literature, research, and

studies on health effects of toxic substances

(Section lo) .

The National Institute of Environmental

Health Sciences analyzes compounds found

at CERCLA sites (Section lo).

Federal Research and Development

Concerning Groundwater Quality

At least 26 Federal organizations are conducting or are planning to conduct research and development (R&D) studies on groundwater quality.

Table 15 lists the organizations and categorizes their

major groundwater quality R&D activities. Most

of the work that is done requires an understanding of groundwater flow systems.

1848 FR 17651-17652. The agency was established fOllOwing settlement of a lawsuit brought by the Environmental Defense Fund (EDF)

against the Department of Health and Human Services for their failure to comply with Section 104 of CERCLA. See Reisch, 1983.
Ch. 3—Federal Institutional Framework To Protect Groundwater From Contamination ● 85

Table 15.—Federal Involvement in Groundwater Quality Research and Development’

Categories of groundwater quality R&Db

Federal organization 1 2 3 4 5 6 7 8 9 10

National Science Foundation. . . . . . . . . . . . . . . . . . . .

Department of Agriculture

Agricultural Research Service. . . . . . . . . . . . . . . . .

Forest Service. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Soil Conservation Service. . . . . . . . . . . . . . . . . . . . .

Department of Commerce

National Bureau of Standards. . . . . . . . . . . . . . . . .

Department of Defense

Army Corps of Engineers. . . . . . . . . . . . . . . . . . . . .

Army Medical Bioengineering R&D Laboratory. . .

Army Toxic and Hazardous Materials Agency. . . . .

Department of Energy. . . . . . . . . . . . . . . . . . . . . . . . . .

Department of the Interior

Bureau of Indian Affairs. . . . . . . . . . . . . . . . . . . . . .

Bureau of Land Management. . . . . . . . . . . . . . . . . .

Bureau of Reclamation. . . . . . . . . . . . . . . . . . . . . . .

Fish and Wildlife Service. . . . . . . . . . . . . . . . . . . . .

Geological Survey. . . . . . . . . . . . . . . . . . . . . . . . . . .

National Park Service. . . . . . . . . . . . . . . . . . . . . . . .

Office of Surface Mining. . . . . . . . . . . . . . . . . . . . .

Office of Water Policy. . . . . . . . . . . . . . . . . . . . . . . .

Environmental Protection Agency

Environmental Monitoring Systems Laboratory. . .

R.S. Kerr Environmental Research Laboratory. . . . .

Environmental Research Laboratory. . . . . . . . . . . .

Office of Pesticide Programs. . . . . . . . . . . . . . . . . .

Office of Radiation Programs. . . . . . . . . . . . . . . . . .

Office of Research and Development. . . . . . . . . . .

Office of Solid Waste. . . . . . . . . . . . . . . . . . . . . . . .

Office of Water. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Nuclear Regulatory Commission. . . . . . . . . . . . . . . . .

x x x

x x

x

x x

x

x x x

x

x

x

x

x

x x

x

Xxx xx x

x x

x x

x x x x

x x

x

x

x

x x

x x x x x

x

x

x x

x

x x

x

The most diverse research programs—in terms

of the number of R&D categories involved—are

those of the Environmental Protection Agency (the

Office of Research and Development is most active), the U.S. Geological Survey, and the Army

Corps of Engineers. Information made available

for this study does not allow a detailed breakdown

of projects within all the agencies.

Institutional involvement is highest—in terms of

the number of organizations conducting research

in a particular category—in the detection of

groundwater contamination and in subsurface fate

and transport of contaminants. Detection efforts

generally involve point sources (e. g., waste piles,

landfills, mine drainage, underground injection

wells, surface impoundments, and septic tanks), but

some efforts are also being directed toward nonpoint sources (e. g., salt-water intrusion, farm runoff, and pesticide applications). Several organizations are also involved in standards certification and

quality assurance, hydrogeologic investigations,

and treatment technologies.

As of 1978, the Federal budget for all water research was approximately $225 million but only $10
86 • Protecting the Nation’s Groundwater From Contamination

million to $12 million was spent on groundwater

R&D (U.S. House of Representatives, 1978). Data

available for this study are not sufficient for estimating current Federal expenditures either on

groundwater quality R&D overall or on specific categories of R&D. In general, groundwater R&D expenditures are not identified as such, and without

detailed budget information, the extent and focus

of Federal groundwater R&D activities cannot be

assessed.

CHAPTER 3 REFERENCES
Chapter 4

State Institutional Framework

To Protect Groundwater

From Contamination
Contents

Chapter 4 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107

TABLES

-/:1/)1(. ,\”() l’aqc’

16. OTA Sta:c Sur\cy Responses: State Activities To Improve Capabilities To Deal

W’ith Grcundwater Contamination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95

17. Orl’A Sta e Survey Responses: Examples of Special Studies To Irnpro\e

State Ca~abilitics To Deal With Groundwater Contamination . . . . . . . . . . . . . . . . . . . . 96

18. OTA Sta e Sur\cy Responses: Distribution of State Special Studies Among

.Source Cfitegories . . . . . . . . . . . . . . . . . , . . . . . . . . . . . . . . . . . . . . . . . 97

1{), O’1’A Stzll c surl.~y Responses: Types of’ Useful Information From Other States . . . . . 97

z(). OTA Stal e Su r~’ey Responses: Number of Statrs Reporting Positive and/or

Negative Effects of Selected Federal Laws and Programs on Effbrts To Deal W’ith

Groundwiter Contamination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99

21. l’ypes of State Groundwater Quality Standards Programs in 1981 and 1983 . . . . . . . . 101

zz. <)’I’A Sta[ e Survey Responses: Strengths and Problems in Programs To Deal With

C~roundw:lter Contamination and Desired Federal Assistance , . . . . . . . . . . . . . . . . . . . . 103

23. OTA State Sur\ey Responses: Types of Sources for Which States Experience

Variati(>ny; in Their .Ability “lo Deal Effectively \\’ith Groundwater Contamination . . 105

FIGURE!;

F’i,yurc ,1’[~. i’,!,ye

1. Number 01 States With Programs To Detect, Correct, or Pre\ent

Groundwater Contamination From Selected Sources in 1981 and 1983 . . . . . . . . . . . . . . 93

‘2. O-l’A State Sur\q’ Responses: Number of States With No Programs 1’o Detect,

Corrt’et, or Prtx’ent Groundwater Contamination From Selected Sources . . . . . . . . . . . . 94
Chapter 4

State Institutional Framework To Protect

Groundwater From Contamination

—— . — —— — — — -— — — -—— — . - CHAPTER OVERVIEW

OTA State Survey

Information on the States presented in this report is based primarily on a survey of all the States

conducted by OTA from June to September 1983.

The objectives of the questionnaire, which was sent

to the State Governors, were to obtain a common

information base for assessing the extent to which

individual States use avaiIable techniques for handling existing groundwater contamination problems

and to learn the status of State efforts concerning

groundwater quality protection. All 50 States responded. Summary information derived from State

responses is discussed in this chapter regarding the

institutional framework; technically oriented issues

related to specific detection, correction, and prevention activities are covered in chapters 7, 10, and

12, respectively.

State responses to the OTA survey reflect the

views of State personnel involved in groundwater

quality programs. Questionnaires received by the

Governors’ offices were forwarded to the State

agencies with groundwater quality responsibilities.

Responses were prepared by a single agency in 36

States, although several programs within the agency

often participated. Fourteen States coordinated

their responses with more than one agency. The

extent to which the response of a single agency

reflects State activities is highly variable, depending on the relative role of that agency in dealing

with groundwater contamination. In view of the

fact that many States are actively developing or

revising their contamination programs, responses

reflect program status only as of the date of the

questionnaire, i.e., summer 1983.

Survey questions were divided into eight categories: sources, detection, corrective actions, prevention, improving capabilities, State policies,

Federal-State relations, and impacts. Emphasis was

on the detection and correction of existing contamination. Thus, further investigation would be required for a detailed analysis of prevention.

A list of the State agencies that responded and

a copy of the questionnaire are presented in appendixes C. 1 and C.2, respectively. Because many of

the questions asked in the survey are open-ended,

the fact that only a few States commented on a particular issue does not necessarily imply that the issue

is not of concern to other States. Issues raised by

the State responses should thus be interpreted as

potentially important to additional States as well.

State questionnaire responses discuss most, but

not all, of the sources of contamination, techniques

for hydrogeologic investigations, and correction

alternatives presented in the technical chapters of

this report. The technical chapters have additional

coverage because they continued to evolve after the

questionnaire was distributed. Nevertheless, State

responses provide a factual and comprehensive basis

for analysis of State activities and concerns.

State Institutional Framework

In this chapter, State perceptions of groundwater

contamination problems and a general description

and assessment of their efforts to handle these problems are presented. ’ The following topics are discussed:

. State perceptions of groundwater contamination problems;

. Overview of State activities to protect groundwater quality from contamination by selected

sources;

1 For more detailed accounts of selected State programs see GAO,

1984; Pye, et al., 1983; Henderson, et al., 1984; National Conference of State Legislatures, 1983; and Magnuson, 1981.

89

38-799 0 - 84 - 4 : QL 3
90 Ž Protecting the Nation’s Groundwater From Contamination

●

●

●

State efforts to improve capabilities to deal with

groundwater contamination;

State perspectives on Federal programs, including Federal water quality standards and

guidance; and

State strengths, problems with their programs

to protect groundwater quality, and types of

desired Federal assistance.

Conclusions drawn from this information are summarized below.

Problems with groundwater quality have been

identified in every State, and all the States are working to improve their efforts to deal with contamination. State efforts to protect groundwater quality

have increased markedly in the past 2 years; for

example, the States are beginning to look at more

types of activities and facilities that are potential

sources of groundwater contamination than previously. However, there are differences in the ways

the States perceive and address contamination problems—different States have different problems, priorities, capabilities, and approaches. Some sources

of contamination are receiving more attention than

others. Some potential sources are not being addressed by most of the States. The States are also

at different stages in developing and implementing programs, and generally, are at the very early

stages.

The States have been more successful addressing some types of sources of contamination than

with others: new v. old, active v. inactive, large

v. small, concentrated v. widespread, point v. nonpoint, non-agricultural v. agricultural, and industrial wastes v. residential wastes. They have also

been generally more successful with sources for

which there is a Federal mandate for action or for

which they have explicit authority. In general, the

focus of State programs is on point sources of

wastes, rather than on non-point sources and nonwaste sources. More States give priority to, and

have developed programs for, prevention rather

than detection or correction.

All the States recognize problems with their efforts to protect groundwater from contamination.

The problems relate primarily to resources (e. g.,

funding, technical expertise, and information and

data) and authority to develop and implement programs. Lack of authority to deal with some sources

is considered a serious problem by almost 40 percent of the States. Although there is a general lack

of uniformity among the States about the sources

for which they do not have authority, at least two

sources—underground storage tanks and agricultural practices—were highlighted by one-half the

States noting problems with authority. z

Current Federal laws and programs are generally helpful to the States. But the level of support

is not perceived as adequate by most States, nor

is support directed at all the specific areas where

the States have identified problems (e. g., Federal

guidance on water quality standards is perceived

as insufficient by many States). In some cases, the

States feel that Federal initiatives have actually

hindered State efforts.

Problems have been created for some States by

some Federal programs. For example:

● programs have resulted in the transferring of

surface water quality problems to groundwater;

. resources have been shifted from groundwater

issues to other Federal priorities;

● programs have failed to provide explicit

2The States obtain authority to address sources of groundwater contamination through a variety of mechanisms. For example, a State

may establish authority through legislation specifically addressing a

source (e. g., regulating solid waste landfills); legislation specifically

addressing groundwater quality (e. g., m+y-dating discharges to groundwater); or more general water quality legislation that enables a State

to protect the quality of State waters (delined to include groundwater

in many States). State legislation may be passed in response to Federal laws or programs, or legislation may be developed by the State

independently of any Federal activities. For example, Federal laws

may require that States establish a program (or the Federal Government will develop a program for the State, as in the Safe Drinking

Water Act) or a Federal law or program may offer a State financial

assistance if the State establishes a program meeting Federal criteria,

as in the Coastal Zone Management Act.

Once a State has established authority to address groundwater contamination, specific programs are developed (unless they are specifically described in the legislation) and implemented. Program development may involve approval of administrative regulations and

guidelines that describe the scope of the program in greater detail than

the enabling legislation. For example, a State may have a law that

authorizes the establishment of standards for groundwater quality,

but the specific standards and the exact circumstances in which they

are applied are established in administrative rules or regulations. Such

administrative rules and regulations may require some type of approval by the State legislature, or they may be up to the discretion

of the implementing agency. State program implementation may require that the legislature appropriate special funds for that purpose,

or program funding may depend on the implementing agency’s making

allocations from its general operation budget.
Ch. 4—State Institutional Framework To Protect Groundwater From Contamination ● 9 1

●

●

●

authority to the States to deal with groundwater quality problems;

programs have not provided adequate and sustained funding for both development and implementation;

programs have not been applicable to the

hydrogeologic conditions in all States; and

programs have had technical deficiencies.

and the differences in State hydrogeologic conditions and institutional arrangements.

The States generally want Federal assistance in

the form of funding, technical assistance, research

and development, information management, administrative improvements, and policy development. Different States want different combinations

of these kinds of assistance and would like assistThese problems are related to the lack of Fed- ance directed toward detection, correction, preveneral goals for groundwater protection and the fail- tion, standards, or, more generally, improvement

ure of Federal programs to recognize both the in- of State capabilities to handle contamination.

terrelationships among all environmental media

STATE PERCEPTIONS ABOUT GROUNDWATER

CONTAMINATION PROBLEMS

Incidents of groundwater contamination have

been identified in all 50 States (USGS, 1984), but

perceptions about what constitutes a problem vary.

For example, some States consider small areas of

contamination or several incidents of contamination a statewide problem; others do not. The extent to which an isolated site-specific problem is of

statewide concern is partly a function of the availability of alternative high-quality water supplies,

the number of further incidents expected from various sources of contamination, and the capability

of a State to detect and correct contamination from

existing sources and to prevent contamination from

new sources.

Several States commented on the future of groundwater protection, Some are pessimistic about controlling contamination, given the complexity of the

problems and the politics and emotions involved.

Other States are optimistic that contamination will

be controlled if they are able to establish and/or implement programs to: 1) prevent groundwater quality degradation from a variety of sources; 2) obtain

a better understanding of hydrogeology, sources,

Photo credits: State of F/orida Department of .Environrnenta/ Regulation

Contaminated groundwater has been detected in every State.
92 Ž Protecting the Nation’s Groundwater From Contamination

and groundwater quality; and 3) detect and cor- ity. Overall, the States are devoting more attenrect contamination from existing sources. tion to preventing contamination than to detectRegardless of their perceptions of contamination ing or correcting it. This pattern is consistent with

State comments on present and future priorities. problems, all the States are working to improve Most States give highest priority to prevention. their capabilities for protecting groundwater qualOVERVIEW OF STATE ACTIVITIES TO PROTECT

GROUNDWATER FROM CONTAMINATION

Historical Perspective

State efforts regarding contamination have been

changing rapidly in the past few years. The number of States working to address particular sources

has increased substantially in the past 2 years.

Some States that have only recently recognized particular sources as problems (e. g., underground storage tanks) are beginning to address them. Figure

1 compares the number of States with programs

either to detect, correct, or prevent groundwater

contamination from selected sources in 1981 with

the number in 1983. Information in the figure does

not imply that all types of facilities and activities

for any given source are included, that the same

facilities and activities are covered consistently from

State to State, or that details of programs for sources

have remained the same over time.

As discussed in chapter 3, the Federal Government has some type of program for nearly all these

sources. The extent to which State activities are a

response to Federal initiatives is not evident from

available information. However, some State requirements are more stringent than available Federal guidance for some sources; other States are

constrained from addressing certain sources by a

lack of Federal initiatives. Further, some States

commented that they can more easily address contamination from sources for which there is a Federal mandate.

Current State Programs

The OTA State survey asked the States whether

they had programs to detect, correct, or prevent

contamination from various sources. Figure 2 shows

the number of States with no program to detect,

correct, or prevent contamination from various

sources. The fact that a State program is directed

at a particular source does not necessarily imply

that all aspects of contamination from that source

are being addressed. A program may be limited to

preventing further contamination from a particular source rather than focusing on detecting and/or

correcting existing contamination. In addition,

State programs may deal only with a subset of facilities and activities of any particular source type.

Two major points are apparent from figure 2:

1) some sources of groundwater contamination are

receiving attention from more States than others.

In general, sources in OTA Category I (sources designed to discharge substances) and Category II

(sources designed to store, treat, and/or dispose of

substances) are receiving the attention of more

States than sources in Category IV (sources that

discharge substances as a consequence of other

planned activities); and 2) not all States are addressing all potential sources. The reasons given

were: 1) the source is not commonly found or does

not occur in the State; or 2) no problems with the

source have been encountered. With respect to the

first reason, sources that are most commonly found

in particular regions include de-icing salts (northern States), salt-water intrusion/brackish water upconing (coastal and western States), and irrigation

return flow (western agricultural lands). With respect to the reason that problems have not yet been

found, it is possible that some problems will not

be recognized until they are looked for. This point

is especially true for the groundwater contaminants

that are often not directly observable by taste, odor,

color, or acute illness.
Ch. 4—State Institutional Framework To Protect Groundwater From Contamination • 93

Figure I.—Number of

SOURCE

a

States With Programs to Detect, Correct, or Prevent Groundwater Contamination

From Selected Sources in 1981 and 1983

Subsurface percolation (1)

Injection wells (1)

Land application (1)

Wastewater

Wastewater byproducts

Landfills (II)

Surface impoundments (II)

Leaks from storage, pipelines,

etc. (II, Ill)

Agricultural runoff (IV)

Urban runoff (IV)

Mining and mine drainage (IV)

Salt-water intrusion/brackish

water upconing (VI)

Spills and accidents

I 1 1 1 I !

o 10 20 30 40 50

Number of States

Key:

w Based on OTA State Survey

Responses, 1983.

■ Based on WRC, 1981.

a The ~ource~ included are those listed on both the OTA and wRc surveys, Roman numerals refer to OTA source Categories (see table 5). See also the footnOtes to

fig. 2 for a description of the sources included.

SOURCE: Water Resources Council (WRC), 10S1; and the Off Ice of Technology Asaeaament.

STATE EFFORTS TO IMPROVE CAPABILITIES TO

DEAL WITH GROUNDWATER CONTAMINATION

States are undertaking a variety of activities to ●

improve their capabilities to deal with groundwater

contamination and are developing institutional

frameworks to support their efforts. In this section,

information provided in State survey responses

about these activities is described. It demonstrates

the general points which follow:

●

● The States are approaching the need to improve their efforts in many different ways.

Most activity to improve capabilities is at an

early stage of development. Training staff and

developing their capabilities, detecting contamination, collecting data on particular

sources or aquifers, and developing management strategies and programs are among the

most commonly reported activities.

All potential sources of contamination, as identified by OTA’s study, are not being considered by all the States.
94 ● Protecting the Nation’s Groundwater From Contamination

Figure 2.—OTA State Survey Responses: Number of States With No Programs To Detect, Correct, or Prevent

Groundwater Contamination From Seiected Sources
Ch. 4—State Institutional Framework To Protect Groundwater From Contamination ● 9 5

As shown in table 16, the highest number of

States are working to improve staff capabilities,

undertaking special studies, and improving coordination among programs. A large number of States

is also involved in public education, facility development, and agency reorganization. Many States

commented that their efforts—especially as related

to staff development and training, public education, and facility development—were limited by insufficient funding. There is a wide variety of State

activities, as shown in tables 17 and 18 and discussed below.

Staff Development and Training. Forty-five

States reported staff development and training

activities to improve their capabilities. Twenty-two

States provided examples of activities, which can

be classified as: classes and conferences (e. g, short

courses, hands-on training, workshops, seminars,

and safety training); benefits (e.g.,, improved salary structures, career ladders, continuing education funding, and management programs); and additional staff. Some States are engaging in more

than one type of activity.

Special Studies. Forty-three States reported conducting special studies to improve their capabilities.

All but two of these States provided examples of

their studies, which cover five major areas: detection, sources and/or contaminants, aquifer characteristics, groundwater management and protection strategy development, and regulatory program

development. The number of States reporting each

type of activity and examples of their studies are

presented in table 17. Some detail is provided about

the types of sources being studied in table 18.

Sources that discharge substances as a consequence

of other planned activities (Category IV) are receiving the most attention.

Table 16.—OTA State Sunrey Responses: State

Activities To Improve Capabilities To Deal With

Groundwater Contamination

Number of States Activity

45 . . . . . . . . . . . . . . . . . . . . . Staff development and training

43 . . . . . . . . . . . . . . . . . . . . . Special studies

42 . . . . . . . . . . . . . . . . . . . . . Coordination programs

36 . . . . . . . . . . . . . . . . . . . . . Public education

29 . . . . . . . . . . . . . . . . . . . . . Facility development

24 . . . . . . . . . . . . . . . . . . . . . Agency reorganization

10 . . . . . . . . . . . . . . . . . . . . . Other

SOURCE Office of Technology Assessment.

Coordination Programs. Forty-two States

reported special coordination programs. All but two

of these States provided examples of their coordination activities, which may be classified as: interagency coordination (e. g., with Federal agencies, among State agencies, and with regional

agencies); program coordination; and other activities (e. g., formation of special groundwater committees, designation of special staff for coordination, management program strategy development,

written agreements, and data base improvements).

The most commonly reported activity was interagency coordination. Of the eight States noting coordination with Federal agencies, seven specified

the agencies; the U.S. Geological Survey (USGS)

was listed by all seven.

Forty-two States also reported benefiting from

information provided by other States. Most information exchange among States occurs informally

through: personal contacts (e,g., direct inquiry,

visits, and informal discussions); attendance at

events (e. g., conferences, seminars, special training sessions, and workshops); written materials

(e. g., publications, newsletters, rules, regulations,

and guidelines); associations (e. g., Association of

State and Interstate Water Pollution Control Administrators, National Governors’ Association, and

interstate commissions); and contact with consultants and experts. Contact through Federal agencies (e. g., Environmental Protection Agency and

USGS) was reported by relatively few States.

Table 19 summarizes major categories of information that the States want from each other. They

are primarily interested in learning about programs—types of approaches, successes, and failures—rather than about the details of individual

sites.

Thirty-two States reported a need to change some

of their own practices to facilitate the exchange of

information among States. Two types of changes

were reported by the majority of States: 1 ) improving data management, such as by establishing an

information clearinghouse, and 2) preparing reports

on State experiences. Several States expressed interest in sharing their experiences through a centralized, national data base, recognizing that much

of the information would have to be keyed to specific hydrogeologic conditions. Several States also

noted that to write, print, and distribute reports
96 • Protecting the Nation’s Groundwater From Contamination

Table 17.—OTA State Survey Responses: Examples of Special Studies To Improve State Capabilities To Deal

With Groundwater Contamination

Number of:

Type of study States Studies Examples

A. Detection studies . . . . . . . . . . . . . . . . . . . . . . . . . .

Problem areas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Program development. . . . . . . . . . . . . . . . . . . . . . . . .

Source-related . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Use-related. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

B. Source and contaminant studies . . . . . . . . . . . . .

Assessments/inventories . . . . . . . . . . . . . . . . . . . . . .

Program development. . . . . . . . . . . . . . . . . . . . . . . . .

Impacts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

C. Aquifer studies . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Baseline data... . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Modeling studies . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Contamination potential . . . . . . . . . . . . . . . . . . . . . . .

D. Groundwater management protection strategy . .

Program development

Contamination response . . . . . . . . . . . . . . . . . . . . . .

Staff development . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Data management improvement . . . . . . . . . . . . . . . .

E. Regulatory program development . . . . . . . . . . . . .

Standard development . . . . . . . . . . . . . . . . . . . . . . . .

Enforcement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

24

18

5

3

1

19

13

6

6

17

14

2

2

12

10

4

1

1

2

33

25

5

5

1

34

16

7

8

21

16

2

3

20

14

4

1

1

5

3

2

Coal mining area studies—UT;TCE studies—

AZ.

Groundwater quality monitoring assessment—

PA; Study of techniques for detection of

pollutants-CT.

Monitoring coal-fired electric generating plant

sludge and ash pits, selected municipal

Iagoons, and selected oil and gas drilling

and production facilities—ND.

Investigating water quality at non-municipal

public supply wells-AR.

Surface impoundment assessment and injection well inventories-AL; Statewide toxic

substances assessment—NM; behavior of

organic contaminants in groundwater—FL;

pesticide studies-CA, Wl.

Bulk storage program development—NY; rules

needed for drilling oil and gas in hydrogen

sulfide areas—OK; irrigation disposal

well alternatives study—lD; Statewide

assessment of magnitude of groundwater

contamination—Ml.

Coal mining impact studies—UT; effects of

salt-water disposal associated with oil field

activities—MS; impact of pesticides on

groundwater–FL, AZ, HI.

Near-surface permeability—FL; recharge area

maps—WV; hydrogeologic studies—GA, DE,

IL, KY, NE, NJ, SC, SD.

Solute transport studies–MS.

Potential for contamination of shallow acquifers from land disposal of municipal

wastes—lL.

Prevention strategies for particular region—

WA, NY; statewide management/protection

strategy—AR, Ml, NE, NY, ND, OK.

Point/non-point tradeoff project—NY; evaluate

aquifer restoration/cleanup schemes—MA;

incident response—NY, VT; Hydrogeologic

Investigation Team—NH.

Staff evaluations—DE.

Groundwater management information system

project—NY.

Develop standards for hazardous chemicals in

groundwater—FL; develop and adopt

groundwater quality standards–OR.

Coordinated UIC program—AR; permittee or

responsibility party studies—DE.

SOURCE: Off Ice of Technology Assessment.
Ch. 4—State Institutional Framework To Protect Groundwater from Contamination ● 9 7

Table 18.—OTA State Survey Responses: Distribution of State Special Studies

Among Source Categories

Total

number of Assessments/ Program

Sources studies inventories development Impacts

a Waste

b Non-waste

c Note that the totals do not add up to the totals in table 17 because some of the contaminant-related studies indicated in

that table (sources and contaminant studies) are not linked to specific source categories.

SOURCE Off Ice of Technology Assessment

Table 19.—OTA State Survey Responses: Types of Useful Information From Other States

Information Number of States a Major topics of interest

Corrective . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 Experience with techniques; case histories; cleanup

standards.

Detection activities. . . . . . . . . . . . . . . . . . . . . . . . 28 Experience with techniques; case histories;

behavior of specific contaminants in particular

hydrogeologic environments; monitoring

programs.

Prevention activities . . . . . . . . . . . . . . . . . . . . . . 14 Experience with techniques, design criteria and

siting requirements for some types of facilities;

Best Management Practices.

Standards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 General water quality standards; maximum contaminant levels; discharge standards; treatment

or technology based standards.

Sources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Groundwater contamination problems associated

with different sources.

Other . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 Groundwater quality management/protection

strategies; risk assessment information; impacts

of groundwater contamination; research results;

legislation; interstate groundwater flow and

quality; public education.

aFortY

.eight states described the types of lnfOrmatlOn that would be useful.

SOURCE Off Ice of Technology Assessment

and studies on their experiences requires increased

staff and support budgets.

Public Education. Thirty-six States reported

public education activities, and 16 listed examples:

written materials (e. g., pamphlets, magazine articles, and use of the news media) and personal contacts (e. g., workshops with consultants, seminars,

and speaker bureaus). Some States noted that they

have public information programs; the programs

may be either general or targeted at particular

sources or areas where groundwater contamination

Facility Development. Twenty-nine States

reported facility development activities, with 22

States listing examples. The most commonly reported activity is related to laboratory improvements (e. g., expansion of State water quality laboratories, certification and quality assurance checks

on private laboratories, upgrading techniques, additional analysis of particular substances such as

organic chemicals or radionuclides, and purchase

of laboratory equipment). Other activities listed include improving computer capabilities, developing

special waste disposal facilities (e. g., State hazardis of concern. ous waste facilities and agricultural chemical wash-
98 ● Protecting the Nation’s Groundwater From Contamination

ing facilities), and establishing quality assurance

programs.

Agency Reorganization. Twenty-four States

reported some type of agency reorganization designed at least in part to improve their capabilities

to deal with groundwater contamination. Twelve

States gave examples, which may be categorized

as: consolidating groundwater expertise in one

group or establishing a special task force; creating

a single agency for the environment or for water

resources; and establishing a special agency or

group for special projects or sites of contamination.

Other Activities. The “other” category listed by

10 States relates primarily to either general program development (e. g., specific laws, priorities,

or standards for groundwater) or data collection

(e.g., improved drilling capability and monitoring

and inventory efforts).

STATE PERSPECTIVE ON FEDERAL PROGRAMS

In this section, two major themes are discussed:

1) whether selected Federal laws and programs have

helped or hindered State efforts to protect groundwater quality, and 2) how States use Federal water quality standards and guidance for groundwater

contaminants.

State Responses About

Selected Federal Laws

In the State survey, the States were asked

whether selected Federal laws and programs have

been a help to them or hindrance. For the most

part, Federal laws and programs have helped many

States address contamination. Several States

pointed out problems with some Federal programs.

In general, States have different problems. They

relate primarily to Federal programs that: shift

problems with the quality of another environmental

medium to groundwater; divert resources to activities other than groundwater; do not explicitly

authorize consideration of groundwater; lack flexibility to address specific conditions in a State;

create administrative problems for a State; do not

fund activities mandated by the Federal Government; and have provisions that the States view as

technically unsound or inappropriate,

Table 20 shows the number of States commenting positively and/or negatively about the laws and

programs. When a State commented both positively

and negatively, the comments may apply to a single

section of a law or to different sections. The ‘‘no

impact comment has several possible meanings:

1) that the law or program does not apply to the

State (e. g., the Bureau of Indian Affairs (BIA) is

active only in States with Indian lands and the

Coastal Zone Management Act (CZMA) applies

only to States bordering seacoasts or the Great

Lakes); 2) that respondents to the questionnaire

were not familiar with the applicability of the law

or program to groundwater issues (e. g., the National Bureau of Standards (NBS)); or 3) that the

law or program has no bearing on the efforts of a

particular State (e.g., Surface Mining Control and

Reclamation Act (SMCRA) and CZMA). Note

that the number of States commenting that a law

or program has no impact on their efforts to deal

with groundwater contamination is relatively large.

In the following discussion, information on the

negative comments is presented in detail. These

comments provide a basis for determining needed

changes in existing laws and programs, or approaches to avoid in establishing new programs,

to help the States with their groundwater contamination problems.

The positive comments, not discussed in detail

here, indicate the types of Federal laws, programs,

and services that the States view as helpful. In general, the positive comments include many of the

points made by the States in their response to questions about how the Federal Government can best

assist them (see the next major section, e.g., technical assistance, funding, research and development, and information management). Positive

comments were also made for Federal programs

that, for example, are flexible and can be tailored

to individual State needs and conditions.
Ch. 4—State Institutional Framework To Protect Groundwater From Contamination ● 9 9

Table 20.—OTA State Survey Responses: Number of States Reporting Positive

and/or Negative Effects of Selected Federal Laws and Programs on Efforts

To Deal With Groundwater Contaminationa

State response

Both positive

Positive Negative and negative No impact

Laws

CWA . . . . . . . . . . . . . . . . . . . 33 2 12 3

SDWA . . . . . . . . . . . . . . . . . . 36 1 10 3

RCRA . . . . . . . . . . . . . . . . . . 33 2 10 5

CERCLA . . . . . . . . . . . . . . . . 31 0 4 15

TSCA . . . . . . . . . . . . . . . . . . . 12 0 0 38

UMTRCA . . . . . . . . . . . . . . . . 7 0 2 41

FIFRA . . . . . . . . . . . . . . . . . . 11 1 37

CZMA . . . . . . . . . . . . . . . . . . 6 0 1 43

SMCRA . . . . . . . . . . . . . . . . . 15 2 1 32

Programs

SCS . . . . . . . . . . . . . . . . . . . . 26 2 1 21

ASCS . . . . . . . . . . . . . . . . . . . 16 0 0 34

NBS . . . . . . . . . . . . . . . . . . . . 4 0 0 46

BIA . . . . . . . . . . . . . . . . . . . . 2 0 1 47

BLM . . . . . . . . . . . . . . . . . . . 7 0 1 42

BuRec . . . . . . . . . . . . . . . . . . 8 0 0 42

USGS . . . . . . . . . . . . . . . . . . 43 0 1 6

WRDA . . . . . . . . . . . . . . . . . . 14 0 1 35

asee text and ch 3 for abbrewatlons.

SOURCE’ Off Ice of Technology Assessment

Federal laws and programs that have influenced

the most States include: the Clean Water Act

(CWA), the Safe Drinking Water Act (SDWA), the

Resource Conservation and Recovery Ac t

(RCRA), the Comprehensive Environmental

Response, Compensation, and Liability Act

(CERCLA), and programs of USGS. Most States

view favorably the contribution these laws and programs have made to their handling of contamination programs. But, with the exception of USGS

programs and CERCLA, a relatively large number of States noted that these Federal programs have

also had negative (or both positive and negative)

effects on their efforts.

It is important to recognize that although one

State may view a particular section of a law as

limited in its application to groundwater, another

State may be using that same provision very effectively. Such discrepancies may reflect differences

among States’ groundwater problems as well as institutional differences (e. g., authority and priorities)

which affect the use of a State’s resources. Negative aspects of these laws and programs mentioned

by the States are described below, with emphasis

on the laws receiving the most negative comments

(i.e., CWA, SDWA, and RCRA).

Clean Water Act. The States were asked to comment on Sections 104 (Research, Investigation,

Training, and Information); 106 (Grants for Pollution Control); 201 (Grants for Construction of

Treatment Works); 205j (Grants for Water Quality

Management Planning); 208 (Areawide Waste

Treatment); 303 (Water Quality Standards and Implementation Plans); and 402 (National Pollutant

Discharge Elimination System, NPDES). Fourteen

States made negative comments about the various

sections. Two major issues were raised about how

the act has hindered State efforts to deal with

groundwater contamination:

1.

2.

Ten States noted that the act has promoted

surface water quality protection efforts to the

detriment of groundwater quality (e. g., land

disposal practices, increased wastewater treatment, and point source discharges in normally

dry streambeds) and has diverted resources

away from groundwater issues.

One State noted that the lack of explicit

authority in the law to address discharges to

groundwater has prevented the State from doing so.

It should be noted that many States are actively

using their discharge elimination permit systems
100 ● Protecting the Nation’s Groundwater From Contamination

to regulate discharges to groundwater (20 States

commented only positively on Section 402).

Safe Drinking Water Act. The States were asked

to comment on the following portions of this law:

Part B—Section 1412 (National Drinking Water

Regulations); Part C—the Underground Injection

Control Program and the Sole Source Aquifer Program; and Part E—Sections 1442 (Research, Technical Assistance, Information, and Training of Personnel) and 1443 (Grants for State Programs). The

negative comments from 11 States about one or

more of these provisions raised two major issues:

1, Six States noted that the provisions of the Sole

Source Aquifer Program and the Underground Injection Control Program were not

applicable to or were of little value for conditions in their States.

2. Six States noted administrative problems with

implementation of the Underground Injection

Program and Sections 1442 and 1443.

Resource Conservation and Recovery Act. The

States were asked to comment on Subtitles C (Hazardous Waste Management) and D (State or Regional Solid Waste Plans) of the act. Twelve States

made negative comments about one or both provisions, with three major points of concern:

1.

2.

3.

Eight States cited problems with administration or implementation of program requirements (e. g., difficulties with requirements for

authorization of State programs or conflicts

between Federal requirements and ongoing

State programs; difficulties in dealing with

EPA staff and coordinating with other EPA

programs; inflexibility of certain rules; and

lack of Federal support for enforcement of

Subtitle D).

Five States noted funding problems, particularly for Subtitle D, but also for monitoring,

laboratory facilities, and staff to implement

Subtitle C.

Three States cited technical shortcomings

within the law: the emphasis on land disposal,

mandated use of liners, and inadequate performance standards that, according to one

State, hinder proper disposal; the lack of information about the adverse effects of various

concentrations of contaminants; the omission

of some known toxic or carcinogenic chemicals from RCRA’s hazardous waste list; and

questions about the applicability of statistical

methods used to evaluate concentrations of

synthetic chemicals.

Other Laws and Programs. The negative comments made by a relatively few States about other

Federal laws and programs generally relate to the

same kinds of problems and concerns discussed

above for the Clean Water Act, the Safe Drinking

Water Act, and the Resource Conservation and

Recovery Act.

That the law or program shifts surface water

quality problems to groundwater was mentioned

by three States with respect to the Soil Conservation Service, by one State with respect to studies

supported by its Water Resources Research Institute, and by one State with respect to the Bureau

of Land Management and the Bureau of Indian

Affairs.

The lack of explicit authority to deal with

groundwater quality problems has been a problem

for one State with respect to the Surface Mining

Control and Reclamation Act (SMCRA). Three

other States noted that SMCRA has little impact

on groundwater quality.

Administrative problems with the Uranium

Mill Tailings Radiation Control Act (UMTRCA),

noted by two States, relate to coordination between

State and Federal agencies; with the Comprehensive Environmental Response, Compensation, and

Liability Act (CERCLA), noted by three States,

relate to problems with coordination and the slow

rate of progress in program implementation; with

SMCRA, noted by one State, relate to retaining

State primacy; and with the Coastal Zone Management Act, noted by one State, relate to coordination problems among State agencies.

Funding problems with the USGS Cooperative

Program were indicated by one State. The State

was unable to participate in the Program because

of the cash payments required for matching funds.

One State mentioned the lack of funding to comply with Federal requirements under CERCLA to

evaluate sites,

Technical shortcomings were noted by two States

with respect to the Federal Insecticide, Fungicide,

and Rodenticide Act (FIFRA); some registered

pesticides have contaminated groundwater.
Ch. 4—State Institutional Framework To Protect Groundwater From Contamination . 101

State Use of Federal Guidance on

Quality Standards for Groundwater

Water quality standards provide a baseline for

detection, correction, and prevention activities, The

States apply standards to groundwater through their

drinking water quality programs and/or groundwater quality programs.

As mentioned in chapter 3, the Federal statutes

require the establishment of quality standards for

drinking water and surface water. The Federal

Government establishes minimum standards for

selected substances in drinking water and provides

guidance for additional substances in drinking water and surface water. Although the Federal Government does not require the States to set quality

standards for groundwater, many States have done

so, especially in the past 2 years, as shown in table

21. States have either established explicit authority for groundwater quality standards or have used

their general authority over water quality (often

based on Federal mandates to control surface water pollution) to address groundwater. Some States

have not developed groundwater quality standards

in the absence of explicit Federal guidance.

Also shown in table 21 are the types of State

groundwater quality standards—i.e., whether

standards are numerical, narrative, or both. Numerical standards specify concentration limits (e. g.,

parts per million of a substance). Narrative standards describe limits but do not specify concentrations (e. g., a non-degradation standard requiring

that concentrations be at or below natural background levels) or even necessarily individual contaminants (e. g., a standard prohibiting the discharge of toxic, carcinogenic, teratogenic, or

mutagenic substances into groundwater). Numerical standards are generally preferable to narrative

standards because the substances that are covered

and the concentrations that are acceptable are

clearly stated. Because of difficulties in obtaining

toxicological and risk-related information (discussed

in ch. 2 and app. A. 1), there are many problems

in developing numerical water quality standards.

State standards are based on available literature;

the States have not conducted their own research

to determine toxicological, risk, and impact information. Some standards are based on the detection limits of instrumentation, for practical purposes, rather than on the appraisal of risks

associated with different concentrations of individual substances.

Major conclusions about State water quality

standards applied to groundwater, compared with

available Federal water quality standards and

guidelines, are discussed below.

Federal drinking water standards and guidance

on acceptable concentrations of substances in water are not adequate for State needs. When Federal standards or guidance are available, the States

often do not rely on them. Although it is not required by Federal law, most States have developed

or are developing groundwater quality standards.

Some States have established drinking water standards for substances in addition to, and/or applied

more stringent standards to, those substances covTable 21.-Types of State Groundwater Quality Standards Programs in 1981 and 1983

Types of standards/number of States

1983 1981

State groundwater quality Not

standards programs Numerical Narrative Both specified Total Total

Programs exist specific to

groundwater. . . . . . . . . . . . . . . . . . . 6 3 10 1 20 8

Programs exist based on

general water quality standards

that apply to both surface water

and groundwater. , . . . . . . . . . . . . . 2 2 1 6 11 1

Developing programs specific to

groundwater . . . . . . . . . . . . . . . . . . . 1 4 1 6 12 9

No program development . . . . . . . . . . — — — — 7 32

SOURCE” Office of Technology Assessment; American Petroleum Institute (API), 1983; and WRC, 1981
102 ● Protecting the Nation’s Grourtdwater from Contamination

ered by Federal regulations. State standards include

numerical limits for many substances for which the

Federal Government has provided no guidance.

The standards States apply to groundwater are

extremely diverse. They have developed standards

for different substances, and when different States

have standards for the same substance, the values

are usually not the same. It is not clear, however,

how different standards affect the level of groundwater quality protection, given the varying behavior

of contaminants in different hydrogeologic environments and the many uses of groundwater.

Appendix C .3, a table on Federal and State water quality standards, indicates the range of drinking water and groundwater quality standards established by the States, the States with these standards,

the standards established by the Federal National

Interim Primary and Secondary Drinking Water

Regulations, and Federal guidance provided by

Health Advisories and Ambient Water Quality Criteria. A summary of comments, drawn from appendix C.3, follows:

●

●

States have developed water quality standards

for numerous substances for which the Federal Government has not established standards

or provided guidance. The States have established drinking water or groundwater quality

standards or other indicators of quality for over

150 substances. The Federal Government has

established standards or provided guidance for

developing water quality standards for less

than half of this number. The Federal Government has provided guidelines for fewer than

20 substances for which no State has standards.

Apart from the substances covered by the National Interim Primary Drinking Water Regulations, few States have developed standards

for the same substances (i. e., different States

●

●

●

have generally developed standards for different substances).

Even when States have standards for the same

substances, the standards are usually not the

same.

State water quality standards differ in stringency from Federal standards or guidelines for

the same substances. In general, State drinking water standards are more stringent than

National Secondary Drinking Water Regulations and Ambient Water Quality Criteria. In

general, State groundwater quality standards

are also more stringent than Federal guidelines, but there are substantial numbers of

substances for which the State groundwater

quality standards are less stringent than Ambient Water Quality Criteria.

Overall, the States have established groundwater quality standards for many more substances than they have established drinking

water standards;3 this may reflect the States’

orientation to the prevention of groundwater

contamination. The substances for which a

State has established groundwater quality

standards are usually different than the ones

for which it has established drinking water

standards. If a State has established drinking water standards and groundwater quality

standards for the same substance, the groundwater quality standard is usually more stringent than the drinking water standard.

3

In New York, the State with groundwater quality standards for

the highest number of substances, groundwater quality standards serve

as guidelines for drinking water quality. Reconnaissance studies conducted by the State arc used to identify water supplies that have the

potential to be contaminated from these substances. More detailed

investigations are undertaken if a potential problem is identified. The

State has found that water suppliers are responsive to the use of

guidelines and has not felt the need to establish formal regulations

(Markusen, 1984).
Ch. 4—State Institutional Framework To Protect Groundwater From Contamination • 103

STATE STRENGTHS AND PROBLEMS IN PROGRAMS

TO DEAL WITH GROUNDWATER CONTAMINATION

AND DESIRED FEDERAL ASSISTANCE

In response to survey questions about strengths

and problems in State groundwater protection programs (e. g., program weaknesses, needed changes,

and limiting factors) and how the Federal Government can be of most assistance, the States brought

up a number of issues related to six topics: 1 )

sources of contamination, 2) general capabilities to

deal with contamination, 3) standards for groundwater quality, 4) detection, 5) correction, and/or

6) prevention. Table 22 summarizes the State responses. Individual responses are presented in appendix C .4; and examples of issues for which each

State appears to be particularly articulate are presented in appendix C.5. Major findings, presented

below, are followed by details on each topic:

• Because the questions were basically openended (i. e., the States were not asked directly

about strengths, problems, and the desire for

Federal assistance with respect to detection,

correction, and prevention), table 22 reflects

the issues that questionnaire respondents

voluntarily raised, perhaps feeling they were

of the greatest concern to their groundwater

programs. The fact that a State did not comment about a particular issue does not necessarily reflect a lack of strengths, problems, or

desire for Federal assistance with respect to

that topic.

●

●

●

The fact that the highest number of States

commented about improving capabilities and

detection probably reflects the early stage of

development of most State programs. That

these issues dominate many States’ concerns

does not mean that they do not need assistance in other areas.

Many States did not highlight any strengths,

all the States noted problems, and nearly all

want some change in Federal assistance efforts.

Comments on strengths relate primarily to the

existence of institutional mechanisms (e. g.,

authority and program regulations) to address

various components of the problems in a State.

Comments on problems relate primarily to

resources (e. g., financial, staff, and information) or authority. Comments on desired Federal assistance address six major categories: 1)

funding, 2) technical assistance, 3) research

and development, 4) new policy development,

5) information management, and 6) administrative improvements. Funding, technical

assistance, and R&D were suggested by the

highest number of States. Six States mentioned

the need for a national policy on protection

of groundwater in order to overcome State

program constraints in handling groundwater

contamination; at least 14 other States want

Table 22.—OTA State Survey Responses: Strengths and Problems in Programs To

Deal With Groundwater Contamination and Desired Federal Assistance

Number of States

Desired

Federal

Issues Strengths Problems assistance Total

Sources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 20 — 33

Improving capabilities . . . . . . . . . . . . . . . . . . . . . . . . 12 48 41 50

Standards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 19 19 28

Detection, ., , ., ... , . . . . . . . . . . . . . . . . . . . . . . . . . 15 38 29

Correction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 19 23 35

Prevention . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0 12 10 18

Total States ... , . . . . . . . . . . . . . . . . . . . . . . . . . . 38 50 48 50

SOURCE’ Office of Technology Assessment
104 • Protecting the Nation’s Groundwater From Contamination

Federal funds for development of State policies and programs.

● The States do not want Federal assistance on

all the problems that they identified. In particular, they do not desire Federal assistance

with problems related to water rights.

● Survey responses reveal a great deal of

variability. One State’s strengths may be

another’s problems. Different States highlight

problems with different sources and different

aspects of programs for improving capabilities,

standards, detection, correction, and prevention. Some States are concerned about establishing authority, and others about either developing or implementing programs. A State

may have different needs for different sources

or for detection, correction, or prevention. In

addition, the States seek different kinds of Federal assistance.

Sources

Strengths and Problems

Thirty-three States commented on the adequacy

of their authority to deal with sources of contamination. Some States listed either strengths or problems with respect to authority for sources, and some

listed both. When both strengths and problems were

noted, they relate to different categories of sources,

different sources within a single category, or different characteristics of facilities or sites of a particular source type. Other comments on sources are related to strengths and problems with detection,

correction, prevention, or improving capabilities.

They are discussed in that context below.

Although the States did not use the same terminology, apparently many sources for which some

States reported having adequate authority are the

same sources for which other States reported inadequate authority. These responses highlight the

fact that the States have different capabilities for

dealing with different sources of contamination and

may indicate that individual States are most concerned about different sources of contamination.

In addition, relatively few States commented on the

adequacy of their authority for specific sources.

However, a relatively large number of States commented on the inadequacy of their authority to deal

with agriculturally related sources (including agricultural wastes, non-point source control, and pesticide and fertilizer use) and underground storage

tanks. No States commented specifically on having adequate authority to deal with these sources.

A State may have adequate authority with regard to some facilities associated with a particular

source but not regarding others. Table 23 lists characteristics of sources for which States reported their

relative success in establishing and/or implementing programs to control groundwater contamination. The relative success of controlling contamination may reflect the ease with which States are able

to acquire authority to regulate different types of

operations (which may in turn relate to public support, available resources, number of facilities, and

Photo credits: Office of Technology Assessment (left) and State of Florida Department of Environmental Regulation (right)

Many States lack adequate authority to deal with agriculturally related activities that are potential sources of

groundwater contamination including fertilizer applications and animal feedlot operations.
Ch. 4—State Institutional Framework To Protect Groundwater From Contamination • 105

Table 23.—OTA State Survey Responses: Types of

Sources for Which States Experience Variations in

Their Ability To Deal Effectively With

Groundwater Contamination

More success Less success

New facilities

Active sites

Large operators, facilities,

sites

Regulation federally

mandated

Concentrated sources

Nonagriculture

Point sources

Industrial wastes

Old facilities

Inactive sites

Small operators,

facilities, sites

Regulation not federally

mandated

Widespread sources

Agriculture

Non-point sources

Household wastes

SOURCE: Off Ice of Technology Assessment

other factors). Success may also reflect the kinds

of options that are available for controlling contamination from different sources (e. g., it may be

easier and less expensive to design new facilities

than to retrofit old ones to prevent contamination).

Federal Assistance

Sources of contamination were not mentioned

specifically when the States listed desired Federal

assistance. Rather, desired assistance related to improving capabilities, standards, detection, correction, and prevention, as described in the following sections.

Improving Capabilities

Strengths and Problems

All of the States commented on their strengths,

problems, and/or desire for Federal assistance to

improve their handling of contamination. Comments on strengths relate primarily to institutional

mechanisms that provide flexibility for responding

to newly recognized problems (e. g., coordination

among State programs, staff training opportunities,

and legislative support). Other strengths include

availability of information on aquifer characteristics as an aid to decisionmaking.

Comments on problems relate primarily to having sufficient resources and support to establish or

implement institutional mechanisms. Almost all of

the States are concerned with having sufficient

funds and staff. Funding problems were reported

by the highest number of States. With staff, the

problems relate to having, attracting, and retaining sufficient numbers of adequately trained personnel.

The States also noted that a number of changes

are required in their programs. Several States recognize problems with their institutional framework,

including lack of authority to deal with contamination, and inability to develop and implement a coordinated strategy (e. g., because of factors related

to regulations and their enforcement). Resolution

of these institutional problems is complicated in

some States by the lack of support of various interest groups, policy conflicts or coordination problems among State agencies and between State and

Federal programs, and the low priority of groundwater relative to surface water.

Federal Assistance

Forty-one States expressed a desire for Federal

assistance to improve their capabilities—apart from

Federal assistance related to standards, detection,

correction, and prevention. Desired types of Federal assistance to improve capabilities, indicated by

the highest number of States, include: general technical assistance for groundwater quality programs;

funding for development of groundwater policies

and programs, State research and development,

and staff training; and Federal activities related to

information management and information/technology transfer. Suggested improvements to Federal

regulatory programs include more flexible regulations to meet individual States’ needs, coordination among Federal laws and among Federal and

State agencies, and adequate funding for federally

mandated programs.

Standards

Strengths and Problems

Twenty-eight States commented about their

strengths and problems with quality standards for

groundwater or drinking water and desire Federal

assistance in this area. Strengths relate primarily

to the existence of standards for groundwater

quality. The most frequently reported problems are

the lack of groundwater quality standards in general and the lack of numerical standards or toxicological or risk information for particular substances
106 . Protecting the Nation’s Groundwater From Contamination

(e.g., volatile or synthetic organics and radiological

substances).

Federal Assistance

Nineteen States reported a desire for Federal

assistance related to quality standards (two of them

also commented on strengths in their own efforts).

Research and development was most frequently

cited (e. g., information on toxicology, impacts, and

risk assessment). Other suggestions are for technical assistance and additional Federal drinking water standards.

Detection

Strengths and Problems

Forty-six States commented about the strengths

and problems with their efforts, and about their desire for Federal assistance, to detect contamination.

Strengths relate primarily to institutional resources

and mechanisms (e. g., staff expertise and coordination among State agencies) to detect contamination, at least from some sources. More States noted

strengths with respect to their detection efforts than

they did with respect to any other category of activity related to dealing with contamination.

Nearly all the States commenting on the strengths

of their detection programs also noted problems.

Problems relate primarily to institutional concerns,

particularly funding and other resource (e. g., staff)

constraints that prevent a State from obtaining data

on groundwater contamination. Not having the

authority to obtain data on particular sources is a

problem for many States. Many noted the need to

modify and increase monitoring activities, although

they differed on focus—whether the emphasis

should be sources of contamination, aquifer characteristics, or ambient quality.

Federal Assistance

Twenty-nine States expressed a desire for Federal assistance specifically related to detection.

Funding for data collection was the most commonly

reported. Research and development for monitoring and technical assistance for hydrogeologic analysis and interpretation were also listed. In addition,

funding, technical support, and R&D for laboratory analysis were noted.

Correction

Strengths and Problems

Thirty-five States commented about strengths

and problems and their desire for Federal assistance with corrective action. In general, their

strengths relate to the existence of institutional

mechanisms (e. g., authority, funding, and priority

ranking systems) to undertake corrective action for

at least some sources. Their problems relate primarily to insufficient funding and other resources

(e. g., staff). Other problems relate to inadequate

institutional mechanisms (e. g., authority, including

water rights, coordination, and enforcement) and

to the lack of technology for correcting contamination in some environments (e. g., karst).

Federal Assistance

Twenty-three States expressed a desire for Federal assistance related specifically to corrective action,

12 of them noting neither strengths nor problems

in this area. The highest number of States specified technical assistance (e. g., to implement corrective action, to train staff on safety and on the

use of corrective action techniques, and to deal with

the public when groundwater contamination is discovered); improvements through research and

development (e. g., low-cost corrective action techniques for treating specific contaminants, for particular sources like on-site waste disposal or oil field

wastes, or for aquifers in general; and cleanup

standards); and funding assistance (e. g., to deal

with contamination in general, existing problems,

large problems, and sources for which Federal funding is not available). Other areas cited by a few

States include: Federal program administration

(e. g., continued support or improvements to the

Federal “Superfund” program); Federal policy development (e. g., establishing a national groundwater policy for prevention and correction); and

development of an information clearinghouse related to experience with corrective action.

Prevention

Strengths and Problems

Eighteen States commented about problems or

desired Federal assistance for prevention of con-
Ch. 4—State Institutional Framework To Protect Groundwater From Contamination ● 107

lamination. No States commented specifically about

strengths in their prevention programs.

Comments on problems were institutional in

nature and relate either primarily to the absence

of or deficiencies in some types of programs for prevention (e. g., classification systems, well-drilling

standards, environmental impairment liability insurance, recharge area protection, and hazardous

waste disposal facilities) or to the lack of resources

to implement existing institutional mechanisms

(e. g., funds for existing prevention programs to

handle more potential sources of contamination).

The technical adequacy of some prevention mechanisms was questioned by one State.

Federal Assistance

search and development activities (e. g., developing

control technologies or Best Management Practices

(BMPs) for additional sources or contaminants and

determining which substances should never be discharged to groundwater) and to funding (e. g., to

implement BMPs and federally mandated programs). Additional Federal assistance is also desired

for information management (e.g., a clearinghouse

for information on State approaches and regulations to prevent groundwater contamination) and

for changes to existing Federal programs (e. g.,

change in the emphasis of RCRA from land disposal to recycling and chemical destruction of toxic

materials and improvements in FIFRA pesticide

registration requirements to increase success in

identifying contamination potential prior to marketing).

Ten States desire Federal assistance for prevention activities. Comments relate primarily to reCHAPTER 4 REFERENCES

American Petroleum Institute (API), “Guide to Ground

Water Standards of the United States, ” 1983a.

American Petroleum Institute, ‘ ‘Underground Leak

Laws , May 6, 1983b.

Feliciano, D., ‘‘ Leaking Underground Storage Tanks:

A Potential Environmental Problem, ” Congressional

Research Service 84-508 ENR, Jan. 11, 1984.

General Accounting Office, ‘ ‘Federal and State Efforts

To Protect Ground Water, 1984.

Henderson, T. R., J. Traubman, and T. Gallagher,

‘‘Groundwater: Strategies for State Action’ (Washington, DC: Environmental Law Institute, 1984).

Magnuson, P., ‘‘Groundwater Classification, September 1981 (copyright by Geraghty & Miller, Inc.,

Svosset. NY. 1982).

Markusen, K., Department of Health, State of New

York, personal communication, Mar. 3, 1984.

National Conference of State Legislatures, ‘ ‘Groundwater Management and Protection: A Midwestern

State’s Policy Agenda, ” June 1983.

Pye, V. I., R. Patrick, and J. Quarles, Gz-oundwater

Contamination in the United States (Philadelphia:

University of Pennsylvania Press, 1983).

U.S. Geological Survey, National Water Summary

1983—Hydrogeologic Events and Issues, USG S

Water-Supply Paper 2250 (Washington, DC: U.S.

Government Printing Office, 1984).

U.S. Water Resources Council (WRC), “State of the

States, Water Resources Planning and Management,

Groundwater Muddlement. ” Mav 1981. / , L 1 ,
Chapter 5

Hydrogeologic Investigations of

Groundwater Contamination
Contents

Page

Chapter Overview.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111

Approaches for Minimizing Difficulties With Groundwater

Contamination Investigations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135

Ensuring the Reliability of Hydrogeologic Investigations .....,. . . . . . . . . . . . . . . . . . . . . . . 135

Approaches f’or Minimizing Difficulties in Measuring Substances . . . . . . . . . . . . . . . . . . . . . 137

Chapter 5 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138

TABLES

Table No, Page

24.

25.

26.

27.

28.

29.

Groundwater Contaminants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Costs and Detection Limits of Methods for Measuring the Molecu

Properties of Contaminants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Techniques Commonly Used To Measure Media-Based

Properties of Contaminants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . 129

ar-13ased

. . . . . . . . . . . . . . . . 130

. . . . . . . . . . . . . . . . 133
Chapter 5

Hydrogeologic Investigations of

Groundwater Contamination

CHAPTER OVERVIEW

This chapter describes the current status of hy -

drogeologic investigations. The first section, The

Conduct of Hydrogeologic Investigations, summarizes the general approach used for investigations, describes the two primary driving forces of

investigations (i. e., site conditions and objectives),

and discusses the design of investigations in terms

of information requirements, techniques, and monitoring networks. (This section is based on

GeoTrans, Inc., 1983a, unless otherwise indicated.)

The second section, Approaches for Minimizing

Difficulties With Groundwater Contamination Investigations, discusses reliability of data collection

and interpretation.

The conclusions that follow are based on this

information.

Hydrogeologic investigations play an integral

role in understanding and evaluating groundwater

contamination regardless of the policy objective

(i.e., whether to detect, correct, or prevent contamination). The techniques for obtaining information on hydrogeologic conditions and groundwater quality are now generally available.

Because of the inherent difficulties in dealing with

the subsurface (e. g., its inaccessibility to direct

observation), there will always be some degree of

uncertainty about contaminants—which substances

are present and at what concentrations, where they

are going, and how fast they are moving. The nature and degree of the uncertainty vary according

to such factors as the hydrogeologic environment,

types of contaminants, the number and history of

the sources involved, and the type of techniques

used. Under most circumstances, the uncertainties

can be reduced, although not eliminated, to obtain

reliable results. The uncertainties are most often

reduced by combining complementary techniques

and/or collecting increasingly detailed site information. These strategies, however, usually increase

the costs of and/or time for an investigation. The

impacts of uncertainties on decisionmaking can be

minimized by making conservative assumptions

and conducting sensitivity analyses.

Design and implementation of investigations are

highly dependent both on site-specific conditions

and on the specific objective to be achieved at a site

(i.e., detection, correction, or prevention). The siteand objective-specific nature of groundwater contamination problems requires that investigations be

tailored to each individual problem. It is thus impractical to standardize requirements for hydrogeologic investigations (e. g., with respect to the number or location of monitoring wells). The burden

of performing reliable hydrogeologic investigations

falls on those responsible for obtaining, interpreting, and applying results; and the required skilled

personnel are in short supply.

Many techniques are available for analyzing contaminants once a groundwater sample has been obtained. Generally, the techniques identify contaminants and quantify their concentrations, but they

also introduce a bias in terms of which of the contaminants present are detected. Behavioral properties of contaminants (e. g., mobility and toxicity),

on the other hand, cannot be measured directly and

thus must be deduced from indirect information,

experience, and judgment. Understanding the behavior of contaminants is important for detection,

correction, and prevention of problems.

117
112 ● Protecting the Nation’s Groundwater From Contamination

THE CONDUCT OF HYDROGEOLOGIC

INVESTIGATIONS

General Approach of Investigations

Hydrogeologic investigations are the process for

collecting and analyzing information on the presence and behavior of contaminants in the subsurface. This knowledge is obtained primarily by collecting and analyzing data on the hydrogeologic

environment (to ascertain the rate and direction of

groundwater flow and help predict contaminant

behavior) and on groundwater quality (to ascertain

the presence and concentrations of contaminants).

Investigations are simplified if information about

the nature and location of sources of contamination is known and if information is available on the

properties of contaminants likely to be found.

Knowledge of contaminant properties is helpful,

for example, in determining how fast contaminants

move relative to groundwater flow or if they move

independently of flow.

Hydrogeologic investigations usually involve the

design and operation of a groundwater quality

monitoring network to collect data on the behavior

of contaminants in the subsurface in order to satisfy

detection, correction, or prevention objectives.1 For

example, to detect contamination from a potential

source, understanding the behavior of expected

contaminants is required to determine where contamination is most likely to be found. To correct

a problem, understanding contaminant behavior

is necessary to determine the nature and extent of

the problem and to predict responses to alternative

corrective measures. To prevent contamination,

understanding contaminant behavior is necessary

to select, design, and evaluate preventive measures.

Key issues in the design of monitoring systems

are: what information is required, what techniques

are applicable for obtaining this information, what

should be the number and location of measuring

points, and how frequently should samples be collected. Answers to these questions depend on conditions at the site and the objectives to be achieved.

‘For sample discussions of methodologies for hydrogeologic investigations, see Todd, et al., 1976; Wood, et al., 1984; and GeoTrans,

Inc., 1983b.

Hydrogeologic investigations of groundwater

contamination problems rely on many of the same

techniques (e. g., groundwater exploration, aquifer

testing, geochemistry, and mathematical modeling

of groundwater flow) developed in the past 60 years

to evaluate groundwater resources for supply purposes. These hydrogeologic techniques were developed primarily to evaluate permeable and saturated

geologic units (e. g., aquifers) covering extensive

areas, most often at the county or regional scale.

For investigations of contamination, the scale is

usually much smaller; and low permeability units,

which can act as a barrier to contaminant migration, and the unsaturated zone, which can retain

contaminants for long periods, can be very significant. Data that were historically collected and analyzed only in special research studies must be obtained routinely in investigations of contamination.

Many simplifying assumptions often used in

groundwater supply investigations (e. g., that the

vertical component of flow is not significant; that

flow in fractured media can be approximated by

an equivalent porous media; and that the unsaturated zone is of minor importance) are often not

applicable in groundwater contamination investigations. As a result, the costs and time required for

these hydrogeologic investigations are higher than

those for water supply investigations. In addition,

the investigation of contamination requires more

precise well drilling and water quality sampling.

Site Conditions

There are inherent difficulties in obtaining information on an environment that not only is

mostly inaccessible to direct observation but is also

extremely variable in both space (i. e., the

hydrogeology at a single site may be complex and

non-uniform) and time (i. e., the rate and direction

of groundwater flow and groundwater quality are

not constant). Each site will have a unique combination of characteristics including:2

‘Listing is based on discussion by Keith, et al., 1982a.
Ch. 5—Hydrogeologic Investigations of Groundwater Contamination • 113

Regional

discharge

area

Local

recharge Local

Monitoring w

*

area

;

Credit: Geraghty & Miller, 1983

Regional groundwater flow is of primary interest in evaluating the water supply potential of an aquifer;

local groundwater flow is of primary concern in investigations of contamination.

sources of contaminants (e. g., associated types

of contaminants and release patterns);

the hydrogeologic environment (e. g., topography, vegetation, climate, geology, surface

and subsurface hydrology, unsaturated zone,

and contaminant transport parameters); and

groundwater use (e. g., effects of pumping rates

and schedules on groundwater flow).

To have confidence that the interpretation of information in hydrogeologic investigations reflects

actual conditions in the subsurface, some investigations require more detailed information than others

on the hydrogeologic environment and groundwater quality, More detailed information is required at sites where: the hydrogeologic environment is very complex (e. g., heterogeneous or

fractured aquifers v. uniform or simple aquifers),

the contaminants present do not move with groundwater flow (e. g., the presence of immiscible v. miscible contaminants), and information is limited

about which contaminants are present, contaminant properties, and sources and their contaminant

release characteristics.

Objectives

The different purposes of hydrogeologic investigations—detection, correction, and prevention—

are presented in table 24. As shown, the design and

operation of a monitoring effort will vary according to the objective to be achieved, the steps to be

taken to meet the objective, and the type of pro-
114 • Protecting the Nation’s Groundwater From Contamination

Table 24.—Elements of Groundwater Protection and Topics for Hydrogeologic Investigations

Detection Correct ion Prevention

Objectives

Identify/quantify existing

contamination

Characterize nature and

extent of contamination

Assess impacts

Steps in meeting objectives

Evaluate detection options—assess

their applicability and potential

impacts

Select detection measures and design

system

Implement detection system

Evaluate performance

Programs

Monitor sources

Monitor supplies

Monitor groundwater resources (e.g.,

ambient quality)

Inventory sources

Characterize nature and

extent of contamination

Reduce/eliminate existing

groundwater contamination

Assess/reduce/eliminate

impacts of groundwater

contamination

Evaluate both technologyand management-based

corrective action options

— assess their applicability

and potential impacts

Select and design corrective

action measures

Implement corrective action

stragtegy

Evaluate performance

Correct sources that are

causing contamination

Correct supplies (uses) that

are contaminated

Correct groundwater resources that are contaminated

Identify potential for

future contamination

Hinder/prohibit contaminants from entering

subsurface

Assess/reduce/eliminate

impacts of future

contamination

Evaluate preventive action

measures — assess

their applicability and

potential impacts

Select and design

preventive measures

Implement preventive

measures

Evaluate performance

Prevent sources from

causing contamination

Prevent supplies from

becoming contaminated

Prevent groundwater

resources from becoming contaminated

SOURCE: Office of Technology Assessment

gram to be implemented.3 Examples of how these

three elements influence the need for information

about the hydrogeologic environment and water

quality in a hydrogeologic investigation is described

below.

Objective. At a given site, an objective to detect

contamination will generally require less detailed

water quality information than an investigation to

correct contamination. For example, in a detection

investigation it may be sufficient to define the

boundaries of a contaminated area; in a correction

investigation, more detailed information about variations in contaminant concentrations within the

area may be necessary to evaluate correction alternatives.

Steps. Steps in meeting an objective also influence the level of detail to be obtained about water

3

0ther factors, such as different motivations for conducting investigations (e. g., a State environmental program investigating threats to

public health; an industry complying with regulatory requirements;

and an industry investigating potential liabilities associated with known

contamination), also influence the nature of the investigation in terms

of funds, time, and expertise that are devoted to the task.

quality and the hydrogeologic environment. Investigations to evaluate the feasibility of options generally require less detailed information than investigations to select and design the action.

Program. Different kinds of programs may require different kinds of information. A detection

program for water supplies may be limited to identification and quantification of contaminants in

public water supplies, as required under the Safe

Drinking Water Act. Monitoring under such a program is relatively straightforward because the measuring points are defined as the existing water supply

wells, and the type of information required is water quality data. There is no need to evaluate the

hydrogeologic environment to determine where to

collect samples. However, samples taken without

information about the hydrogeologic environment

and associated flow system provide only a single

snapshot of water quality-at the place and at the

time the sample is collected; they cannot be used

either to predict whether water quality is likely to

change or to indicate the location of the source of

contamination. Alternatively, a detection program
Ch. 5—Hydrogeologic Investigations of Groundwater Contamination ● 115

to determine whether a source is in fact contaminating groundwater requires information on the

hydrogeologic environment near the source—in addition to the collection and analysis of water quality

samples —in order to identify areas that are most

likely to show evidence of contamination.

Design of Hydrogeologic

Investigations of Groundwater

Contamination

Information Requirements

Contamination investigations require information on the hydrogeologic environment, water

quality, sources of contamination, and properties

of contaminants, as shown in table 25.4 The importance of this information in understanding the

behavior of subsurface contaminants is also presented in table 25. The major points of the table

are summarized below:

● The primary purposes for collecting hydrogeologic data are to determine the rate and direction of groundwater flow, evaluate the types

of contaminants likely to be found, and determine whether the contaminants and the

groundwater are likely to be moving at the

same rate and direction.

● Information on the hydrogeologic environment (i. e., surface conditions—topography,

vegetation, climate and surface water hydrology; geology; and subsurface hydrology—

unsaturated zone, groundwater hydrology,

contaminant transport parameters, and groundwater use) is obtained primarily to describe the

flow of groundwater. Evaluating flow involves

the collection of data on the quantity, timing,

rate, direction, and pathways of water moving from the surface through the unsaturated

zone and into and through the saturated zone.

Information about the hydrogeologic environment is important in understanding whether contaminants will move at the same rate as

groundwater or if physical, chemical, and/or

biological processes are likely to occur that will

cause them to move at different rates.5 Anal- — .

4Hydrogeologic terms are defined in app. D.

5Chemical and biological processes can alter the rate of contain inant movement, change contaminant concentrations, and transform

the contaminants that are present. These processes are a function of

ysis of the physical, chemical, and biological

properties of the hydrogeologic environment,

along with information on the properties of

contaminants, is needed to evaluate the behavior of contaminants in the subsurface.

The hydrogeologic environment is dynamic,

and information on spatial and temporal variations is also important to assess contamination

problems accurately. Some human activities

can influence the flow of groundwater (e. g.,

pumping groundwater for use can alter the direction of flow, and modifications to the land

surface can alter the amount of water infiltrating to the groundwater system).

● Information on water quality is collected primarily to determine the nature and/or verify

the extent of contamination. Water quality information also contributes to knowledge of the

nature and rate of chemical and biological

reactions that influence contaminant behavior.

● Information on sources of contamination is

useful in predicting the types of contaminants

likely to be present, their locations, and their

concentrations. When interpreted along with

data on groundwater flow and associated contaminant behavior, source data can be used

to predict the location, rate, and direction

of contaminant movement. Knowledge of

sources aids in determining the area to be inboth the properties and concentrations of the contaminants present

and the properties of the hydrogeologic environment (i. e., the unsaturated and saturated zones). Chemical processes include: adsorption-desorption, oxidation-reduction, acid-base, solution-precipitation,

ion pairing or complexation reactions; and radioactive decay. Chemical

processes are least significant in clean sand aquifers and some crystalline

environments. Biological processes may be direct (e. g., enzyme activity) or indirect (e. g., production of metabolizes; alteration of pH and

Eh conditions; and provision of a surface for the accumulation and

concentration of contaminants). Biological processes may result in the

uptake, decay, or transformation of organic materials or the generation of additional contaminants. These processes can be particularly

confusing in investigations of a source when information is available

on the original contaminants but not on their altered states. For example, biological processes can transform trichloroethylene (TCE) io

vinyl chloride, tetrachloroethylene to trichloroethylene, and heptachlor

to heptachlor epoxide (McCarty, 1984). Biological processes are most

significant in zones of higher oxygen availability and larger pore spaces,

such as the unsaturated zone.

Physical processes include dispersion, whereby dissolved contaminants spread in ways that would not be predicted if the contaminants were moving only with the groundwater. Dispersion is a

function of the hydrogeologic environment. It is independent of the

properties of the contaminant. Dispersion results in an apparent faster

movement of contaminants, relative to the average groundwater flow,

at lower concentrations. Dispersion is especially important in fractured systems.
116 . Protecting the Nation’s Groundwater From Contamination

Table 25.—importance of Information Used in Hydrogeologic Investigationsa

B. Vegetative data

C. Climatic data (precipitation;

evapotranspiration; site temperature)

D. Geologic data (surficial deposits;

subsurface stratigraphy; Iithology;

structural geology)

E. Surface hydrology data (overland flow;

stream discharge; stage; recurrence

interval; baseflow discharge)

Information obtained for Importance of information for

hydrogeologic investigationsb

understanding contaminant behavior in subsurface

L information on the hydrogeologic

environment

A. Topographic data Provide partial information on flow (i.e., rate, directions, and

pathways of unsaturated zone and groundwater flow and relationship of groundwater to surface water including: relative

position of water levels in wells, locations of possible discharge and recharge areas, rates of infiltration and surface

runoff, and general direction of groundwater flow).

Provide partial information on flow (i.e., rate and pathways of

water movement into and out of the subsurface). Also

vegetation type and condition may reflect the quality of

groundwater and be used to identify areas of contamination.

Used to estimate depth to water table and identify possible

discharge and recharge areas.

Provide partial information on flow (i.e., the quantity, timing,

and rate of movement of water and contaminants into the

subsurface). Provide basic information to assess rate of

reactions and biodegradation of contaminants.

Provide partial information on flow (i.e., location and volumes

of potential groundwater supplies, pathways for water and

contaminant movement into and out of underlying

formations, and direction and rate of groundwater

movement) and are used to identify possible recharge and

discharge areas. Also, provide partial information on

mechanical dispersion (mixing) and attenuation reactions of

contaminants.

Provide partial information on flow (i.e., quantity, rate, and

timing of water movement into and out of subsurface). Used

to identify and quantify possible discharge and recharge

areas, and to identify potential conduits for contamination.

Surface water may affect concentrations of contamination at

discharge points.

Provide partial information on flow (i.e., on the flow regime

which influences the rate, direction, and quantity of water

and contaminants moving from the surface into

the saturated zone). Usually relatively unimportant in the

humid areas such as the Eastern United States.

Provide partial information on flow (i.e., the rate, direction, and

quantity, of groundwater and contaminant flow). Also,

provide partial information on recharge and

discharge characteristics.

F. Unsaturated zone data (water table;

geometry; hydraulic properties: effective

porosity, effective permeability, relative

permeability, permeability, specific

storage; flow parameters: pressure head,

hydraulic gradient, fluid saturation;

recharge/discharge: surface water

characteristics, precipitation/

evapotranspiration)

G. Groundwater hydrology (Saturated Zone)

data (aquifer characterization: confined

aquifers, unconfined aquifers, leaky

aquifers; hydraulic parameters of aquifers:

storativity, transmissivity, primary

permeability, secondary permeability, primary porosity, secondary porosity;

confining unit geometry; hydraulic

parameters of confining units: hydraulic

conductivity, specific storage; flow

parameters: water levels, hydraulic

gradient, flow velocity; recharge/

discharge: surface water characteristics,

precipitation contributions, confining layer

leakage, fracture/matrix flux)

H. Contaminant transport parameters Provide partial information on properties of the hydrogeologic

(distribution coefficient; dispersivity co- environment that influence the potential for physical,

efficient; flow velocities; relative chemical, and biological reactions that result in

saturations; cation exchange capacity; contaminants moving at different rates than water through

subsurface mineralogy; ambient water the groundwater flow system.

chemistry; microbiology)
Ch. 5—Hydrogeologic Investigations of Groundwater Contamination • 117

Table 25.—importance of Information Used in Hydrogeologic Investigationsa—continued

Information obtained for Importance of information for

hydrogeologic investigationsb

understanding contaminant behavior in subsurface

1.

Il.

Ill.

Iv.

A.

B.

Groundwater use (current usage;

projected usage)

Information on water quality

(contaminants present; concentrations)

Information on sources of contamination

(location; contaminants; release

characteristics: location, volumes,

contaminants, concentrations, timing)

timing)

Information on properties of contaminants

Molecular-based properties

Media-based properties

Provides partial information on flow (i.e., the influence of

groundwater pumping on the rate and direction of

groundwater and contaminant flow). Also provides

information on impacts of contamination.

Provides data on concentrations and distribution of

contaminants.

Provides data on types of contaminants that are likely to be

present, requirements for collecting and analyzing samples,

and suitability of different types of corrective action. Also

provides data on flow (i.e., used to describe and predict the

rate and direction of contaminant movement and the

location of contaminants).

Provide information to identify which contaminants are

present and at what concentrations.

Provide information used as a basis for deducing contaminant

behavior (e.g., persistence and mobility). -

a Based on GeoTrans. Inc., 1983b b Hydrogeologlc terms are defined In app D 1

SOURCE Off Ice of Technology Assessment

●

vestigated, the sites for collecting water quality

samples, and sampling and analysis procedures.

Information on properties of contaminants is

important in understanding the rate and direction of contaminant movement, the location

of contaminants relative to the water table and

less permeable units, the persistence of the contaminants in the subsurface, and the types of

techniques that can be used to detect, correct,

and prevent contamination.

The properties of contaminants that are

most important for their detection in the subsurface relate to volubility. Hydrogeologic investigations of contaminants that are only

slightly soluble (immiscible) require more information on the hydrogeologic environment

and water quality than may be needed to describe contaminants that move with groundwater flow, Immiscible fluids that are also

more dense than groundwater (e. g., many industrial solvents) may move in a different

direction than groundwater flow. Immiscible

fluids that are less dense than water (e. g.,

many petroleum products) tend to float on top

of the water table and may require water

quality sampling in the unsaturated zone.

Although all the hydrogeologic information

shown in table 25 is useful for accomplishing investigation objectives for most site conditions, the

amount and types of information collected in practice is limited because of the time and costs of obtaining and analyzing data. The information collected varies, depending on site conditions and

study objectives. Examples of different information needs according to objectives were discussed

in the preceding section on Objectives. The major

site conditions that determine the information to

be collected relate to the complexity of the hydrogeologic environment, the climate, the number of

potential contamination sources, and knowledge of

the behavior of the contaminants. G

cExamples of variations in information collected under different site

conditions are described below:

●

●

●

●

In fractured (as opposed to unfractured) aquifers, information

is needed on fracture patterns, joint patterns and spacings, and

possibly dual porosity properties (i. e., primary and secondary

permeability and porosity).

In semi-arid (as opposed to humid) climates where the water table

is deep, information on the properties of the unsaturated zone

(e. g., moisture content and relationships between relative

permeabilities and capillary pressure) is very important for defining groundwater flow and determining the potential for contamination.

Where multiple sources (rather than a single source) of contamination are suspected, water quality sampling and analysis may be

directed more to contaminants that are unique to a particular

source, perhaps at very low concentrations, than to contaminants

that are likely to be found at the highest concentrations.

Where the behavior of contaminants can be readily described-for

example, by having knowledge that the contaminant is quickly

degraded or strongly retarded in groundwater—collection of data

on water quality can be concentrated in areas near the source

rather than over a wider area.
118 ● Protecting the Nation’s Groundwater from Contamination

Source of product Source of product

t

-

(Greater density than water) (Lesser density than water )

Unsaturated

zone

I

Saturated Direction of

zone groundwater flow

Product flow

.

Flow of dissolved product

Credit: Geraghty & Miller, 1983

Immiscible contaminants that are more dense than water may not move in the same direction as groundwater flow.

Immiscible contaminants that are less dense than water tend to float on top of the water table.

Techniques for Obtaining Information

About the Hydrogeologic Environment

The presence and concentrations of most contaminants are determined from groundwater quality samples. Techniques for sample collection are

discussed in this section on the hydrogeologic environment, and the analytical techniques for measuring the contaminants in a water quality sample

are discussed in the next section on contaminants.

Techniques used to describe the hydrogeologic

environment and to collect groundwater quality

samples are organized into 12 major categories in

table 26. The table outlines the general types of information obtained from the techniques and the

limitations of the techniques under different conditions.

In general, some information on the behavior

of subsurface contaminants can be obtained and

interpreted with greater reliability than others.

Groundwater flow can be readily described in most

environments; however, information cannot be

readily obtained on the physical, chemical, and

biological processes that may cause contaminant attenuation. This difference reflects both the state

of scientific understanding and available technology. For example, groundwater flow is better understood and mathematical modeling of flow is

more highly developed than for contaminant behavior; thus data can be interpreted more reliably,

and more accurate predictions can be made for

groundwater flow than for contaminant behavior. 7

Summary points and findings from table 26 are

highlighted below:

● Techniques. There are many techniques for

obtaining information about groundwater flow

and the movement of contaminants.

7For a more detailed discussion of differences in models for groundwater flow and contaminant behavior, see OTA, 1982.
Table 26.—Techniques for Hydrogeologic Investigations: Information Obtained and Principal Constraints on Applicationa

Major site constraints

Techniques Information Subsurface geology Subsurface hydrology Water quality Surface conditions Other constraints

 10 identity geologic, ny- type of geologic Complexity of subsurface con- Not a constraint. Not a constraint.

published informa- drologic, hydrogeologic, formation: May not ditions: Usually data are untion water-quality, topo- -

graphic, and climatic

conditions.

2. Mapping To delineate surface

geologic, soil, or

topographic conditions.

3. Remote sensing To assess indirectly

(aerial photography geologic, hydrologic,

and thermal, infra- hydrogeologic, or

red, and radar water quality

satellite imagery) characteristics of the

earth’s surface. A

reconnaissance tool

to optimize surface

field studies.

4. Excavations and To access directly the

drilling subsurface environment for the purpose

of geologic sampling,

geophysical logging,

water quality sampling, and fluid pobe sufficiently detailed available for specific sites,

for complex geologic but some regional hydrogeosettings. logic information may be useful, particularly in simple,

uniform hydrogeologic settings.

Not a constraint. Not a constraint. Not a constraint. Site access: Inaccessible terrain may be

problematic during

ground surveys.

Depth: Techniques Saturation conditions: Some

generally provide techniques (e.g., radar) to

information on only detect presence of contaminaface features but some tion are applicable only in

techniques may provide unsaturated areas where there

some information on is a moisture difference beshallow groundwater tween contaminated and

flow and/or con- uncontaminated areas.

taminant seepage Flow system: Detectable conwithin 10 feet of the lamination limited to disIand surface. charge areas with techniques

Type of geologic formation: other than radar.

Some techniques can

penetrate the surface

and provide information

on contaminants if

under thin alluvium or

sand.

Depth: Excavations Not a constraint.

generally only done at

less than 20 feet.

Applicability of

different drilling techniques varies with

depth; however, with

tential measurements. use of proper equipment, holes can be

drilled to virtually any

depth.

Type of geologic formation: Some drilling

techniques can be

used in only certain

types of materials (soil

versus rock, consolidated versus unconsolidated, prone to caving

versus non-caving).

Nature of Chemical Com- Climate: Some techniques

pounds: Contaminant are weather dependent;

distribution can be cloud cover interferes

detected by various tech- with all techniques

niques if chemicals except radar.

stress vegetation, Timing: Some techniques

cause tonal changes are accomplished best

in surface water, or at different times of

thermal anomalies. day (e.g., predawn or

midday) and seasons.

Nature of chemical Scale: Excavations can

compounds: Presence of cover larger areas than

certain contaminants drilling.

may limit use of some Site access: H may be difProprietary data may

limit availability.

Nonsite-specific

information often

adequate; represents separate

cost. May require a

relatively long time

to complete (days

to months).

Nonsite-specific

information often

adequate; represents separate

cost.

Property access: May

require a relatively

long time to

complete (days to

drilling fluids to avoid ficult to reach some sites months). Relatively

sample contamination. (e.g., steep or marshy) with high cost to imVariations in contamina- steep or marshy) with plement.

tion with depth may some types of equipIimit use of certain ment.

techniques to avoid

cross-contamination.
Table 26.-Techniques for Hydrogeologic Investigations: Information Obtained and Principal Constraints on Applicationa—continued

Major site constraints

Techniques Information Subsurface geology Subsurface hydrology Water quality Surface conditions Other constraints

5. Geologic sampling To identify directly Depth: Type of sample Not a constraint. Not a constraint.

stratigraphy and that can be obtained

geologic structure depends on the depth

and to obtain and penetration capgeologic samples for ability of drill rig and/

laboratory testing of or sampling equipment.

 - . hydraulic and soil Depth is not a limiting

characteristics. factor for obtaining

either undisturbed

samples from some

unconsolidated

materials, or representative and

non-representative

samples from any

type of materials.b

Type of geologic formation: Some limitations

depending on whether

consolidated or unconsolidated. See Depth.

6. Hydrometeorolog- To quantify temperature, Not a constraint. Not a constraint.

ical measurements precipitation, evapotranspiration, and

infiltration at the

earth’s surface.

7. Surface hydrology To identify flow and

(hydraulic measure- water quality

ments; surface characteristics of

water sampling) surface water.

8. Subsurface Hydro- To measure subsurface

logy water level or presa. Potential sure for evaluating

measurements direction of flow and

Not a constraint. Not a constraint.

Depth: Depth is a limit- Saturation conditions: Choice

ing factor for some of techniques depends on

techniques (e.g., some whether measurement is retensiometers and drill quired for the saturated or

to calculate flow rates

.

stem tests). However, unsaturated zone.

within and between techniques are availhydrologic units in able to obtain measureboth the unsaturated ments at any depth,

and saturated zones. provided specially designed wells are drilled.

Type of geologic formation: Fine-grained, low

permeability material

limits the use of certain techniques (e.g.,

standpipes). However,

Not a constraint.

Nature of chemical compounds: Difficult to obNot a constraint. May require a

relatively long time

to complete (days

to months).

Not a constraint. Field techniques to

measure transpiration are difficult

to apply, so estimates are usually

made. Nonsitespecific information

often adequate; represents separate

cost.

Not a constraint. Nonsite-specific information often adetain samples of many or. quate; represents

ganic compounds that separate cost.

are only slightly

water-soluble.

Not a constraint. Not a constraint. Not a constraint.
w

I

o

I

I

-l

.

w

Table 26.--Techniques for Hydrogeologic Investigations: Information Obtained and Principal Constraints on Applicationa—continued

Major site contraints

Techniques Information Subsurface geology Subsurface hydrology Water quality Surface conditions Other constraints

a. Potential

measurements

(cent’d)

b. Hydraulic testing To determine the

hydraulic properties

of in-situ subsurface

materials needed for

calculations of flow

rates in the unsaturated zones or

directly measure

groundwater flow

velocities and to determine contaminant

transport parameters.

c. Laboratory testing (hydraulic,

geologic)

d. Water quality

sampling

To measure the hydraulic properties of samples of subsurface

materials needed for

groundwater flow calculations of variably

saturated materials

(e.g., porosity) and

selected contaminant

transport parameters

(e.g., adsorption).

To obtain a subsurface

water sample representative of in-situ

water quality for

analyses of the pretechniques are available to obtain measurements in any type of

formation provided

specially designed

wells are drilled.

Type of geologic forma- Complexity of subsurface con- Not a constraint.

tion: Some unsaturated ditions: Some techniques

zone techniques (e.g., (e.g., slug tests and flow

infiltration tests) are meters) measure conditions

impractical in coarse- only at or near the point of

grained soils due to measurement, and do not

the amount of water re- account for spatial heterogequired. Choice of tech- neities.

niques (e.g., slug test, Saturation conditions: Some

pressure injection test, techniques are applicable in

and pump test) for either saturated or unsaturated

saturated zone depen- zones.

dent on permeability

of formation.

Depth: Testing dependent Complexity of subsurface con- Not a constraint.

on obtaining appropri- ditions: Superior to field

ate type of sample (i.e., measurements of vertical perundisturbed, repre- meability of fine-grained unsentative, or non- consolidated materials. Major

representative). limitation is small sample

Type of geologic formation: size and the applicability of

Depends on whether extrapolating point information

consolidated or uncon- to the three-dimensional

solidated. See Depth. space being assessed.

Provides good method

of measuring permeability of fine-grained

unconsolidated mateerials. Choice of

geologic sampling

technique (hydrometer

v. sieve tests) depends

on grain size.

Depth: Some pumps to Complexity of subsurface conevacuate wells and ob- ditions: Multiple completion

tain samples have wells to characterize vertical

depth limitations. distribution of water quality

Type of geologic formation: are limited due to concerns

sence and concentra- In high permeability about the effectiveness of

tions of chemicals formations, evacuation sealing to prevent hydraulic

and other substances of sampling wells to connections and the ability

in unsaturated and ensure sample is not to obtain representative

saturated zones. affected by the well samples from different

is problematic. sampling zones. Saturation

However, techniques conditions: Different techNature of chemical compounds: Casing, well materials, and pumps must

be selected both to

resist deterioration from

long-term exposure to

natural chemicals or

contaminants and to

minimize interference

with the measurement of

specific constituents.

Current knowledge of

Not a constraint. Relatively high

equipment cost; intensive manpower

requirements; and

need for skilled personnel. May cause

short-term changes

in water levels.

Tracers may have

adverse environmental effects.

Not a constraint. Not a constraint.

Not a constraint. Not a constraint

are available to min- niques are used to obtain sam - sampling interferences is

imize the amount of pies in the unsaturated zone limited for most well

pumpage required materials.
Table 26.—Techniques for Hydrogeologic Investigations: Information Obtained and Principal Constraints on Applicationa—continued

Major site contraints

Techniques Information Subsurface geology Subsurface hydrology Water quality Surface conditions Other constraints

d. Water quality before sample collection, Design constraints of mulsampling which may in turn limit tiple completion wells

(cent’d) selection of the most (e.g., small diameter) may

effective sampling may limit use of most

equipment for parti- effective sampling equipcular constituents. ment for some chemical

parameters. Proper disposal

of evacuation water prior

to sampling is dependent on its quality.

Techniques used to

evacuate wells and obtain samples may result

in incorrect measures of

some compounds

(especially dissolved

gases and volatile

organics). Also, the

presence of some

constituents (e.g.,

sediment) may damage

some types of

equipment. Some

techniques allow excessive exposure to the

atmosphere or other

gases that might influence the measurement

of specific parameters.

Complexity of subsurface con- Not a constraint. Not a constraint.

ditions: choice of modeling

technique (i.e., analytic or

numeric) depends on complexity of problem. Modeling

complex systems limited by

cost of obtaining data. Most

geostatistical methods require

that the sample population be

normally distributed; thus if

data represent complex subsurface conditions, geostatistical methods may be

difficult or impossible to

apply.

10. Surface geophysics To assess indirectly Depth: Depth limitations Complexity of subsurface condi- Nature of chemical com-

(electrical resistivity

Climate: Some techniques

stratigraphy and ex- are dependent on tech- tions: Techniques applicable pounds: Chemicals of in- requiring electrode conand electromagnetic tent of subsurface nique. Generally, tech- only in relatively simple strati- terest must be capable of tact not applicable in

conductivity; ground- contamination to aid niques cannot be ap- graphic conditions. Natural both inducing a change frozen soils or in dry

penetrating radar; in placement of plied at depths greater subsurface properties must be in the subsurface param- sandy areas (e.g., electriseismic refraction; monitoring well sand than 500 feet. sufficiently uniform so as not eter measured by the cal conductivity). Howshallow geothermic to reduce number of Type of geologic forma- to confuse or mask the ef- method and showing a ever, other techniques

9. Hydrogeologic To simulate or predict Not a constraint

system analysis the behavior of sub-

(modeling; geo- surface hydrogeologic

statistics) units, including

groundwater flow

and solute transport;

or to estimate the

values of hydrogeoIogic phenomena at

unmeasured points.

Relatively high cost

to implement. May

require a relatively

long time to

complete (weeks to

months). Specialized skills required.

Requires a clear definition of the

hydrogeologic parameters used, including their variability in time and

space.

Relatively high equipment cost; need for

skilled personnel;

may require a relatively long time to

complete (weeks to

months).

method) - wells. tion: Minimum detecta- fects of chemicals. Natural different response than are applicable in these
Table 26.—Techniques for Hydrogeologic Investigations: Information Obtained and principal Constraints on Applicationa—continued

Major site contraints

Techniques Information Subsurface geology- Subsurface hydrology Water quality Surface conditions Other constraints

10 Surface geophysics ble concentration conditions that may be surrounding subsurface conditions (e.g., elec-

(cent’d) -

11. Subsurface (borehole) geophysics

(acoustical; electrical-magnetic; nuclear; flow; thermal;

geochemical)

strongly Influenced by responsible for false detection conditions,-Many tech- tromagnetic conducproperties of subsur- or nondetection Include: dis- niques (e.g., resistivity tivity).

face materials. Condi- continous, thick layers of clay; and conductivity Nature of surface: Conduc

tions that may prevent hydrogeologic heterogeneity; methods) generally are tors (e.g., metal fences,

good results include: variations in natural ground- ineffective for defining overhead power lines,

naturally conductive water chemistry due to organic contaminant paved areas, buildings,

brackish water, steep changes in geologic materials; plumes. However, the storage tanks, and bu -

water table, crystalline and variations in surface

rock, and karst or other topography.

environs where ground- Some methods are more effecwater flow IS concen - tive than others for detecting

trated along lntercon- small fracture zones containnected fractures in ing high contaminant concenmassive bedrock. trations (e.g., electromagnetic

conductivity iS better than

electrical resistivity).

Homogeneous subsurface environments having layers of increasing densities present interpretative difficulties for

some techniques (e.g., seismic

refraction). All techniques

generally require subsurface

drilling or monitoring for verification of results.

Saturation conditions: Some

techniques can be used to obtain some types of information only in the unsaturated

zone (e.g., electrical resistivity

can track contaminant movement in only the unsaturated

zone).

presence of organic ried pipelines or wires)

chemicals and petroleum may impair use of some

products may be techniques.

delineated in sand or Sensitivity of different

gravel aquifers at depths

generally less than 25

feet with ground

penetrating radar.

Relatively high concentrations required by techniques for detection of

contaminants. Techniques only provide

gross information on

concentrations of some

individual constituents.

Some techniques can be

effective in delineating

extent of high concentrations of inorganic contamination in suitable

geologic environments.

techniques to these features is variable. Bare

rock, wetlands, shallow

lakes, and dry sandy

areas prevent use of

techniques requiring

electrode contact.

To measure direct physi- Depth: Not a Iimiting fac- Saturation conditions: Some Nature of chemical com- Not a constraint. Relatively high cost

cal properties of sub- tor for most tech--

surface materials to niques provided an unevaluated Iithology, ge- cased borehole can be

ologic structure, hy- drilled.

draulic properties, wa- Type of geologic formater quality, and flow. tion: Most techniques

can be used only in

uncased boreholes,

and thus cannot be

used in geologic formations that cave in

when drilled. Exceptions include nuclear

logs which can be

used in cased boreholes. Some techtechniques (e.g., electricalmagnetic logging techniques)

are applicable only in saturated zone. Some techniques

can be used to provide certain

types of information in the unsaturated zone, and other

types of information in the

saturated zone (e.g., neutron

logs).

pounds: Some tech- to implement.

niques applicable only if

constituents in groundwater have properties

that will induce response

from instruments (e.g.,

spontaneous potential

logs). Some techniques

can be used to detect

particular contaminants

(e.g., Draeger tubes can

detect over 140 in-situ

soil gases).
Table 26.—Techniques for Hydrogeologic Investigations: Information Obtained and Principal Constraints on Applicationa

-continued

Major site constraints

Techniques Information Subsurface geology Subsurface hydrology Water quality Surface conditions Other constraints

11.

12.

Subsurface

(cent’d)

Hydrogeochemistry To perform field testing

of water samples to

determine need for

further laboratory

chemical analysis and

to analyze for unstable constituents.

niques more suitable

for obtaining information on particular types

of geologic materials

(e.g., natural gamma

logs for obtaining clay

unit properties).

Not a constraint. Not a constraint. Nature of chemical com- Not a constraint.

pounds: Field techniques

available to obtain information on conductance,

organic vapors, alkalinity,

pH, Eh, DO, iron, and

hydrocarbons. (See Subsurface Hydrology —

Groundwater quality

sampling, for additional

constraints.)

Not a constraint.
Ch. 5—Hydrogeologic Investigations of Groundwater Contamination ● 125

..

Photo credit: U.S. Geologic

Techniques are available for the direct sampling of groundwater quality.

al Survey

● Information Obtained. Regardless of what

techniques are used, which parameters are

measured, and whether the measurements are

taken directly or indirectly, all measurements

must be interpreted in conjunction with other

data to determine groundwater flow and the

behavior of contaminants. Interpretation of

data is uncertain because of factors relating to:

the precision, accuracy, or detection limits of

the equipment; lack of a unique measurement

(e.g., geophysical response) for particular subsurface conditions; the degree to which averaging of conditions masks actual conditions; and

the degree to which the sample or the measurement represents in-situ phenomena.

Some techniques are useful in obtaining

general information; others are used to obtain

site-specific information. Some techniques

(e.g., excavation and drilling) are not used to

provide information per se, but their use is a

necessary step before other techniques can be

applied. Other techniques (e. g., mathematical

modeling) are not used to measure properties

of the hydrogeologic environment but can be

used to simulate conditions and predict groundwater flow and movement of contaminants.

Techniques are generally available to collect data on the unsaturated zone, groundwater hydrology, sources, and contaminants;

this information is necessary to make reliable

predictions of groundwater flow and estimate

current and future water quality in most environments. However, historic data and data

reflecting changes with time (e. g., groundwater use and the contaminant release characteristics of sources) are usually not available

for a specific site, which diminishes the reliability of some investigations.
126 ● Protecting the Nation’s Groundwater From Contamination

● Constraints. Factors that can limit the use of Some techniques are limited to particular subdifferent techniques are related primarily to

site conditions, costs, and the availability of

skilled personnel. Additional constraints include problems with property access and the

potential for adverse effects.

Site conditions that can limit the use of

hydrogeologic techniques include: subsurface

geology (e. g., depth and type of geologic formation); subsurface hydrogeology (e. g., complexity of subsurface conditions, saturation

conditions, and flow system); water quality

(e. g., nature of the contaminants), and surface conditions (e. g., presence of buildings,

pavement, power lines, vegetative cover, and

other features; site accessibility; climatic factors; time of day; and size of the area).

As shown in table 26, site constraints on obtaining information vary for different categories of hydrogeologic techniques as well as for

specific techniques within each category (e. g.,

surface conditions (e. g., different techniques

are used for the saturated zone than for the

unsaturated zone). In addition, the site constraints that apply to a particular technique

vary, depending on the purpose for which the

technique is used (e. g., subsurface geology

constraints on geologic sampling depend on

the type of sample that is needed).

There are a few types of information that

cannot be obtained reliably using any technique including: chemical reactions in fluids

containing multiple contaminants, properties

characterizing in detail groundwater flow and

chemical transport in fractured media, certain

hydraulic properties of very low permeability

media, in-situ determinations of hydraulic

properties in the unsaturated zone when immiscible contaminants are present, and history

of the contaminating source.8

climate is a constraint only on certain remote 8

See ch. 2 for discussion of the problems associated with determinsensing and surface geophysical techniques). ing the contribution of a source to groundwater contamination.

Photo credit: U.S. Environmental Protection Agency

Remote sensing equipment can be used to identify, document, and evaluate groundwater quality problems. The data

acquisition system, which is mounted on the aircraft and operates 500-10,000 ft above ground level, includes

(from left to right): an instrument logger for recording location, time, and altitude; a control console;

a multispectral scanner; and an aerial mapping camera.
Ch. 5—Hydrogeologic Investigations of Groundwater Contamination ● 127

The costs of applying hydrogeologic techniques depend primarily on site conditions and

the objectives to be achieved. Costs of hydrogeologic investigations to define contamination problems can range from $25,000 to

$250,000, and litigation can double the figure

(Miller, D., 1982). Many factors determine

costs: the complexity of surface and subsurface conditions, areal extent of the study area,

number and frequency of measurements, availability and quality of existing information, site

access, experience and training of personnel,

reliability and capability of equipment, availability of equipment, geology, weather, and

the need for site-specific v. regional data.

These same factors also determine the amount

of time required, and they affect the choice of

equipment and the number and locations of

measurements to be taken.

Equipment costs limit the use of certain

techniques (e. g., hydraulic testing, hydrogeologic systems analysis, surface geophysics, and

subsurface geophysics). Either less costly or less

sophisticated techniques are used. The costs

of applying certain techniques (e.g. geologic

sampling, potential measurements, water

quality sampling, and subsurface geophysics)

are reduced if a well or borehole can be used

for more than one purpose. However, the information required to meet particular objectives will influence the decision on whether to

use a single well or borehole for several techniques. Investigation costs can also be reduced

by using indirect or field screening techniques

to provide reconnaissance level information for

selection of direct measurement locations.

Availability of reliable equipment capable

of operating efficiently under the site conditions is an important factor in determining

costs (e. g., choice of drilling methods and

pumping equipment depends on site conditions). Capital expenditures for major equipment and materials vary, depending on the

purpose and technical sophistication of the

equipment. Certain types of equipment are

more readily available in some areas of the

country than others because of their other uses

(e.g., subsurface geophysics equipment is used

extensively for petroleum and mineral exploration).

The experience and training of personnel

affect costs in terms of the level of skills needed

to design an investigation and collect and interpret data. Highly specialized skills are required for some techniques, and skilled people are in short supply. The result is relatively

high costs to obtain their services.

Property access may limit the use of drilling

and associated techniques. Permission to drill

wells is often not readily granted on private

property because of the inconvenience and disruption created by the drill rig. Interest in

drilling beyond property boundaries is often

quite low because whoever finances the drilling

must usually assume liability for damages.

The potential for short- or long-term adverse

effects limits the use of some techniques. For

example, short-term changes in water levels

during hydraulic pump tests may limit their

use in some environments (e. g., where there

are water supply wells). Use of tracer tests is

unacceptable to many regulatory authorities

because tracers (some of which maybe radioactive) may remain as a potential contaminant

in the environment.

Techniques for Obtaining Information

About Contaminants

Advances during the last decade in techniques

for analyzing water quality samples—for identifying increasing numbers of specific substances, for

detecting substances at progressively smaller concentrations, and for increasing the automation of

instrumentation—have been major driving forces

behind the detection of contaminants in groundwater. Continued improvement is expected; not

only will previously undetected substances be found

but more will be detected at increasingly small concentrations.

Not all contaminants, however, can be detected

at low concentrations using routinely available techniques. Further, the fact that certain substances can

be measured at increasingly small concentrations

does not mean that they need to be. Rather, analysis should be guided by the levels at which substances may cause adverse impacts (Environ Corp. ,

1983). Major unresolved issues concern which

substances and concentrations to measure, given

limited resources, in order to evaluate the risks to
128 ● Protecting the Nation’s Groundwater From Contamination

public health and to provide the public with confidence that it is being protected.

At present, techniques for measuring substances

in groundwater are not being used consistently, and

they introduce a bias in terms of which of the substances present are detected. In addition, analytical accuracy becomes increasingly difficult to

achieve as concentrations become very small and

mixtures become more complex (Woodward-Clyde

Consultants, 1983; Shifrin, 1984).

Properties of Substances. —Analyzing contaminants in a groundwater sample is based on the capability of instrumentation to discern certain properties of substances. These properties are important

in contamination studies because they are characteristic of either individual substances or groups of

substances and because they determine the nature,

behavior, and response of substances under various

conditions.

In the context of groundwater contamination, a

distinction can be made between two types of properties, molecular-based and media-based (Woodward-Clyde Consultants, 1983).9 Measurement of

these two types of properties is based on different

principles. In addition, the two relate to different

objectives. For example, the detection of contaminants in a groundwater quality sample (e. g., determining the general presence of substances or identifying and/or quantifying the concentrations of

specific substances) is based principally on the

measurement of molecular-based properties. Molecular-based properties are derived solely from the

basic construction of the substance: 1) elemental

composition (i. e., elements and their frequency of

occurrence in a molecule); 2) structure (i. e., spatial

arrangement of elements); and 3) functional group

(i.e., arrangement of elements into stable combinations). In contrast, media-based properties are the

principal basis for characterizing the behavior of

contaminants. Understanding behavior is necessary

for designing hydrogeologic investigations including: evaluating the applicability of corrective actions, assessing the vulnerability of an aquifer to

contamination, and assessing health and environmental impacts. Media-based properties are derived

not only from the basic construction of a substance

‘For the purposes of this SI udy, substances have been organized into

nine groupings (see ch. 2, footnc)te 7 and table 6).

but also from its concentration in solution (in this

case, in groundwater) and its interaction with the

surrounding (e. g., hydrogeologic) environment. Although molecular-based and media-based properties are interrelated by molecular composition, this

interrelationship is not well understood.

Information examined as part of this study, about

the current status of the techniques for analyzing

substances that are found in groundwater, is summarized below.

Measuring Molecular-Based Properties. —Many

analysis techniques are available for measuring the

molecular-based properties of substaces in groundwater, as shown in tables 27 and 28 (WoodwardClyde Consultants, 1983). Many of these techniques are routinely available and have been standardized—i. e., they are ‘ ‘referenced’ and published

by the scientific community. Many standardized

techniques have also been sanctioned by EPA—

i.e., protocols have been established to ensure that

the regulated community applies techniques consistently and to facilitate enforcement. 10

With general (also known as non-specific, surrogate, or indicator) methods, it is possible to discern

molecular-based properties that are common to,

and hence can be used to determine the presence

of, groups or classes of molecules. The major advantages of general methods are that they are relatively inexpensive in terms of both capital costs and

costs per sample, and their use requires neither sophisticated equipment nor highly skilled technical

personnel. The shortcomings include that many

general methods can neither measure low concentration levels (i. e., several parts per billion or less)

10Standardized methods have been subjected to statistical tests of

precision (i. e., the reproducibility of results) and accuracy (i, e., the

proximity of the measured results to the actual value) when used to

detect substances in a representative group of samples. Detection using

standardized methods therefore is not to depend on the specific nature

of the sample.

Development of analytical methods for measuring substances in water has intensified since the passage of the Federal Water Pollution

Control Act Amendments of 1972. The act’s requirements triggered

widespread analysis of surface water as well as municipal and industrial effluents for biochemical oxygen demand (BOD), chemical oxygen demand (COD), and other general parameters. Enforcement

of regulations developed pursuant to the 1972 Amendments led to the

need for a high degree of uniformity in the conduct of analytical programs to ensure consistency and equity within the regulated community. EPA first sanctioned the use of methods for measuring both general parameters and specific parameters in EPA, 1974 (revised 1979).
Ch. 5—Hydrogeologic Investigations of Groundwater Contamination ● 129

Table 27.—Analytical Methods for Measuring the Molecular-Based Properties of

Groundwater Contaminantsa

Contaminants Routinely b

Methods measured Available

substance)

GC (gas chromatography, both

gas-liquid and gas-solid)

HPLC (high performance liquid

chromatography)

Detection systems

CD (conventional detectors)

MS (mass spectrometry)

Inorganic

General methods

Eh (Oxidation potential)

Specific conductance

pH/acidity

Contaminant-specific methods

AA (atomic absorption spectrometry)

ICAP (induction-coupled argon plasma)

Wet chemistry

Colorimetry

Gravimetry

Titrimetry

Radionuclides

General methods

Gross emission

Contaminant-specific methods

Concentration/i dentification

Microorganisms

General methods

Standard plate count

Multitube fermentation

Membrane filtration

Contaminant-specific methods

Culturing

Morphology

Concentration/Identification

Organics

Polynuclear aromatics

Organics

Organics

Oxidizing metals

Ionized species

Mineral acids

Metals/cat ions

Metals

Non-metals/anions

Metals

Acids

Yes

No

No

No

Yes

Yes

Yes

Yes

Yes

Yes

Yesd

Yes

Yes

Yes

Yes

Yes

Yes

Yes

Yes

Yes

Yes

Yese

Yes

Aerobic and facultative

anaeorbic, heterotrophic

bacteria

Coliform bacteria

Coliform bacteria, pathogens,

parasites

Yese

Pathogens

Parasites, fungi
130 ● Protecting the Nation’s Groundwater From Contamination

Table 28.—Costs and Detection Limits of Methods for Measuring the Molecular-Based Properties

of Contaminantsa

Costs b ($) Detection Iimitsc

Method Per sample Capital (ppm) (ppb)

15-30

30-60

20-40

10-30

30-60

20-30

20-40

60-100

20-30

30-70

30-500

100-1,500

40-500

10-15

3-5

3-5

10-15

150

125-200

10-35

75/group

1,000/strain

40-75

1,000-1,500

9,000-15,000

12,000-30,000

5,000-16,000

5,000-12,000

4,000-6,000

4,000-6,000

1000-2,000

8,000-10,000

500-1,500

1,000-2,500

8,000-30,000

55,000-220,000

8,000-40,000

1,000-1,500

1,000-1,500

1,000-1,500

500-1,000

12,000-20,000

125,000-175,000

2,000-5,000

2,500-4,000

2,500-4,000

5,000-7,000

30,000-60,000

1

(O.1)d

(1)

0.002

0.002

0.025

0.01

0.2

0.01

<0.001-01

<0.001-0.01

0.000001

N/A

N/A

±0.1 pH unit

±0.1 mg CaC03/l

<0.001–0.2

<0.001-0.2

01-1

N/A

N/A

l-2pCi/l

l-loo pCi/lf

0.05-1 pCi/lg

1,000

(loo)

(1,000) —

2

2

25

10

200

10

<1-1oo

<l–l o

0.001

<1-200

<1-200

100-1,000
Ch. 5—Hydrogeologic Investigations of Groundwater Contamination ● 131

nor identify individual substances of a group or

class. Individual substances would be of concern

if they were expected to vary in terms of their potential impacts. In addition, data from general

methods can be difficult to interpret, especially

when interferences arise from the presence of several different types of substances in the sample.

These interferences are known to give misleading

results (‘false positives’ (Davis, 1984).

With contaminant-specific methods, it is possible both to identify individual substances and to

quantify their concentrations at extremely low

levels. The disadvantages of contaminant-specific

methods are that they are more costly than general methods, and they require the use of relatively

sophisticated equipment. These methods, as well

as general methods, are also subject to quality control problems with analysis procedures, and data

can be difficult to interpret (e. g,, there will always

be some degree of uncertainty about how well data

represent in-situ conditions).

Three important points about measuring molecular-based properties are discussed below related

to: 1) which substances can be measured, 2) the

extensive use of gas chromatography/mass spectrometry (GC/MS), and 3) the ‘ ‘standardized’

concept as it relates to groundwater contamination

(see Woodward-C1yde Consultants, 1983).

Substances Measured. —Not all known or potential substances can be detected at trace levels using

routinely available standardized methods. Some

of these substances have been, or may be, associated with toxic effects in either clinical or laboratory studies.

Organic chemicals:

● There are no routinely available general

methods for measuring trace levels of some

organic chemicals known to occur in groundwater, including aromatic and polynuclear

hydrocarbons. There are no general methods

for measuring trace levels of some substances

that have the potential to be found in groundwater—e. g, glycols and oxygenated hydrocarbons such as aldehydes, ethers, esters, ketones,

and alcohols,

● Standardized contaminant-specific methods

—namely gas chromatography/mass spectrometry, GC/MS—tend to be available for only

●

selected organics (i. e., 129 ‘‘Priority Pollutants’ and pesticides regulated under CWA).11

There are no cost-effective methods for meas-
132 . Protecting the Nation’s Groundwater From Contamination

Photo credit: U.S. Environmental Protec(/on Agency

Gas chromatography/mass spectrometry equipment is

used for the qualitative identification and quantitative

measurement of individual organic chemicals.

2.

3.

molecular weight, substances that are unstable

at high temperatures, and substances that are

highly soluble in water. In many of these

cases, relatively simple, modified versions of

some standardized GC/MS procedures are

adequate (e. g., for malathion); in other cases,

entirely different methods, such as High Performance Liquid Chromatography (HPLC),

may be required (Davis, 1984). Specialized

modifications of standardized GC/MS methods may also be possible for additional

substances such as dioxin (2,3,7,8 -TCDD);

dioxin is difficult to detect because it is relatively insoluble in water and often present at

concentrations of only parts per trillion. In

general, none of these other techniques have

been standardized and used routinely.

Standardized GC/MS methods could be applied directly (i. e., without modification) to

substances in addition to the Priority Pollutants (e. g., xylenes and aniline). Although

EPA has made significant research and development commitments to improve the basic instrumentation of GC/MS and associated data

processing systems, less attention has been

given to widening the routine use of standardized GC/MS methods for additional substances (e. g., by expanding the list of Priority

Pollutant organics).

While contaminant-specific techniques, such

as standardized GC/MS methods, are costeffective for identifying substances in a sample of unknown composition if the substances

are amenable to analysis by the methods, the

methods may be otherwise inefficient (i. e.,

very costly) for unknown samples. Little research attention has been given to developing techniques for substances not amenable

to analysis by GC/MS or to developing reliable and inexpensive screening techniques

(e.g., alternative types of analytical and physical/chemical testing methods) for narrowing

the universe of potential substances that might

be present in a sample and therefore for efficiently determining which contaminant-specific techniques are most applicable (Davis,

1984; Woodward-Clyde Consultants, 1983). 12

Standardized Methods. -Central to the standardization of methods is the concept of a representative sample (refer to footnote 10). This is a difficult concept to apply to groundwater samples

because groundwater contamination is site-specific,

and the ‘ ‘representative samples’ used to standardize a method may not represent the universe of

groundwater samples to which the method might

be applied. Thus the use of a standardized, routinely available method does not guarantee that substances in groundwater can be detected with the

precision and accuracy indicated by following the

standard procedures.

Measuring Media-Based Properties. —Once

substances in groundwater have been identified by

measuring their molecular-based properties, it is

often essential to understand their behavior.

Behavioral characteristics—e. g., persistence and

mobility-determine, for example, the extent of the

contamination problem and likely impacts. However, with present techniques, behavioral characteristics of a substance cannot be measured directly.

Rather, the characteristics are deduced from the

media-based properties of the substance. These

properties are determined by the nature of the sub-
Ch. 5—Hydrogeologic Investigations of Groundwater Contamination ● 133

then deduced using this information together with

professional judgment and experience (e. g., to perform correlation analyses).

Approaches for the Measurement of Substances

in Groundwater. —Techniques for measuring substances in groundwater are not now being selected

and used consistently to ensure that all potential

contaminants at a given site are being addressed,

that substances are being detected efficiently given

time and financial constraints, and that information obtained can be meaningfully interpreted,

consuming and costly; high-quality data required for correlations are

often not available; and published data are often incomplete, inconsistent, or imprecise. For example, published data are found in such

references as Weast, 1978-1979; Perry, et al., 1973; EPA, 1981; Windholz, et al., 1983; and Sax, 1979. Data tend to be limited to such properties as density, viscosity, ignitability, corrosivity, miscibility,

volubility, and vapor pressure. Information is not available for all substances and is often not sufficiently accurate for analysis of tram levels.

Moreover, while some of these properties, such as ignitability and corrosiveness, are used for classifying wastes as hazardous (under RCRA),

they contribute little information about the behavior of such substances

in groundwater. Other properties that are of interest to groundwater

contamination studies, such as adsorption, bioaccumulation, and the

partition coefficient (i. e., the tendency of a substance to partition between soil and water) are not generally available and must bc measured using groundwater samples.

Table 29.—Techniques Commonly Used To Measure Media-Based Properties

of Contaminants

Media-based property Techniques employed

Density Measure forces transmitted by a mass of the substance being

analyzed as in viscous-drag, gas-density meter.

Viscosity Measure fluid friction by either mechanical drag between driven

and free members immersed in the sample or resistance to

flow.

Adsorption Use batch test or leaching columns.

Volubility Dissolve measured amount of contaminant in a given volume of

water at room temperature.

Volatility Estimate quantity of contaminant vaporized from water by use

of an Organic Vapor Analyzer (OVA).

Immiscibility Shake contaminants in water and observe if there is complete

mixing.

Bioaccumulation Determine concentration of contaminant in sample (e.g., via fish)

and compare with background level.

Reactivity Observe violent reaction of contaminant and/or generation of

toxic gases, vapors or fumes when mixed with water.

Degradability Measure CO2 evolution, or determine rate of disappearance of

parent compound over time.

Stability Observe disappearance of parent compounds or generation of

daughter products.

Oxygen uptake Determine biochemical oxygen demand (600) or chemical

oxygen demand (COD).

Partition coefficient Measure concentration of contaminant in soil relative to

concentration of contaminant in water.

SOURCE: Woodward-Clyde Consultants, Inc., 1983.
134 • Protecting the Nation’s Groundwater From Contamination

given the objective (detection, correction, or prevention) of the measurement program. A coherent

approach would consider measuring molecularbased properties with both general methods (e. g.,

as screening tools to narrow the choice of possible

substances present) and contaminant-specific methods (e. g., to identify individual substances and determine their concentrations). 15

EPA has made efforts in the direction of a master scheme for measuring substances (e. g., EPA

Method 8600 is being developed as a comprehensive analytical scheme to determine the presence

of chemicals listed in Appendix VIII of RCRA,

Part 261). Agency efforts are not yet coordinated

in a way that responds fully to the spectrum of

substances found in groundwater and possibly at

extremely low concentrations.

For example, the groundwater indicator parameters to be measured at both interim status facilities (40 CFR 265) and permitted facilities under

the detection monitoring system (40 CFR 264) are

delineated as pH, Specific Conductance, Total

Organic Carbon (TOC), and Total Organic Halogens (TOX). Some substances known to cause adverse health impacts are not detectable using the

indicator parameters. TOC and TOX measurements have the disadvantages of general methods

discussed above (e. g., subject to interference effects). In addition, there are categories of contaminants that are neither halogenated, acidic, nor

conducting and that may be toxic at less than 1 part

per million (ppm, the detection limit of TOC) including pesticides and pesticide byproducts (e. g.,

dioxin and 2,4,5-T, both of which are known to

occur in groundwater; see ch. 2) (Woodward-Clyde

Consultants, 1983). “To a great extent, because

of an overreliance on indicator parameters, we

don’t know much more now about which sites are

‘clean’ or ‘potentially dirty’ than we did before EPA

started using the indicator monitoring approach 3

years ago” (Davis, 1984).

Monitoring Networks

Hydrogeologic investigations involve collecting

information about the hydrogeologic environment

and water quality at selected locations and then

making assumptions about what is likely to be

occurring between sampling points. In general, the

more the sampling points, the less uncertainty is

associated with interpretation of what is taking place

in the subsurface. But practical considerations limit

the number of measurements taken. The number

of measuring points (for direct techniques), the density of measurements (for indirect techniques), and

the verification that is required to obtain a satisfactory level of confidence in the results depend on

site conditions and the objective of the investigation.

To account for horizontal and vertical variations

in the hydrogeologic environment and in water

quality, both the location of sampling points and

sampling frequency will vary depending on site conditions and objectives. For example, measuring

points could be located at random or in an evenly

spaced pattern, or in relation either to the pathways

of substances (i. e., measuring points are located

where substances are either expected and/or not expected to be found) or to concentrations (i.e., measuring points are located where concentrations are

highest and/or lowest). Sampling could be conducted once, annually, seasonally, or more frequently, depending, for example, on whether

groundwater flow patterns change periodically.
Ch. 5—Hydrogeologic lnvestigations of Groundwater Contamination ● 135

Source of contamination

Monitoring

wells

. . *

.“*.

n

i

● ✍

✎ “ . . “” & .“11’. 1

.

● ● *

. 

● ●

Unsaturated zone

Unconfined aquifer

Confining unit

Confined aquifer

Confined aquifer

with fractures

● . Contaminated groundwater ● . ● *

●

 Groundwater flo w

In order to detect contamination, sampling wells need to be located at varying depths and

Credit: Geraghty & Miller, 1983

distances from the source.

APPROACHES FOR MINIMIZING DIFFICULTIES WITH

GROUNDWATER CONTAMINATION INVESTIGATIONS

Ensuring the Reliability of

Hydrogeologic Investigations

As described in the previous sections, investigations of groundwater contamination are very complex and uncertain because the hydrogeologic environment is not easily observed, and hydrogeology

varies both spatially and temporally. Hydrogeologists cannot describe and predict with absolute confidence the rate, direction, and pathways of contaminant movement in groundwater. Estimates can

be made and ranges of values given but there will

always be some degree of uncertainty about which

contaminants are present, where they are moving,

how fast they are moving, and their concentrations

as they move.

Despite these uncertainties, investigations are

under way, and they are used as a basis for mak-
136 ● Protecting the Nation’s Groundwater From Contamination

ing decisions about I he need for and usefulness of

alternative corrective and preventive actions. Given

the nature of such decisions—e.g., regarding public

health and the dollars involved-decisionmakers

and the public need some assurance that certain

elements of uncertainty are minimized and that

hydrogeologic investigations provide reliable

results.

Factors that tend to increase uncertainty in investigations of groundwater contamination include:

complex hydrogeologic environments; lack of historic information about sources of contamination;

substances that do not move with groundwater (because they are immiscible, or due to physical, chemical, and biological processes that alter their nature

or retard their movement); changing patterns of

groundwater use; and inexperienced or untrained

individuals designing investigations and collecting

and analyzing hydrogeologic information.

All of these factors reflect conditions at the site

and are beyond the direct control of decisionmakers, except the choice of personnel. Most of the siterelated factors that contribute to uncertainty can

be overcome by an experienced hydrogeologist,

provided sufficient time and funds are available.

That is, steps can be taken such that the uncertainties do not undermine ability to make reliable predictions about the response of contamination to

Photo (<redIt: U.S. Environmental Protection Agency

Special precautions must be taken to ensure that

samples are not contaminated by the sampling

equipment. This photo shows aquifer material bein g

extruded from a core sampling tube while a sterile

shaving device removes material that has been in

contact with the inside of the sampler.

various corrective or preventive measures. For example, by collecting more information over a longer

period on the presence of substances and the rate

and direction of groundwater flow, investigators can

reduce many uncertainties about complex hydrogeologic environments, sources of contamination,

and changing patterns of water use. The one major exception, where reliable predictions are unlikely, is in fractured environments (e. g., karst regions

of the southeastern United States).

Uncertainties about immiscible substances that

do not move with groundwater can be reduced with

the collection of more information, especially about

the hydrogeologic factors that control the movement

of such substances. The uncertainty associated with

the behavior of substances that do not move with

groundwater flow due to physical, chemical, and

biological processes cannot be reduced significantly,

given technical limitations in understanding these

processes. However, precautionary steps can be

taken to minimize the impact of this and any other

remaining uncertainties, including: using sensitivity

analyses to test the significance of varying assumptions about groundwater flow and the behavior of

substances; using conservative or worst-case assumptions about groundwater flow as the basis for

designing corrective or preventive measures; and

continuing the monitoring of groundwater flow and

water quality as part of the implementation of any

program to corrector prevent contamination so that

any errors in predictions about the response of contaminants can be recognized early and compensating actions can be undertaken.

These precautionary steps may lead to overdesign and higher costs for corrective or preventive measures. However, overdesign may be the

only way to limit risks associated with the lack of

precise knowledge about the concentration and

location of substances and the rate and direction

of their movement.

An additional step that can be taken to improve

reliability, and perhaps to reduce future costs and

time required, is to keep records on the use of

groundwater and the location of potential sources

and their associated substances, With these records

the hydrogeologist will have a better idea about

which substances are of concern at a site and where

to look for them.
Ch. 5—Hydrogeologic Investigations of Groundwater Contamination ● 137

Approaches for Minimizing

Difficulties in Measuring Substances

Analysis of water quality samples is a technically

complex process, and the difficulties associated with

accurate measurement and interpretation of data

are discussed in the literature (e. g., Keith, et al.,

1982b, 1983; Miller, S., 1982). Uncertainties can

be introduced at many steps—including when the

sample is collected, handled, transferred, stored,

prepared for analysis, as well as analyzed (Shifrin,

1984). Thus, detection limits (as presented in table

28) are not absolute; they depend on many factors,

including the skill and experience of the analyst,

the combinations and concentrations of the substances present, and the equipment used. For example, acceptable ranges for precision and accuracy, used for EPA-sanctioned methods by contract

laboratories, range from 15 to 50 percent and 15

to 200 percent, respectively, depending on the

organic classes measured (Keith, et al., 1983).16 

In all cases, uncertainties in the analytical results

need to be defined if the data are to be correctly

interpreted. This need is especially important for

the types of groundwater samples for which a high

degree of accuracy is not now attainable—samples

in which there are complex mixtures of substances,

samples in which substances are present at trace

concentrations, and samples being analyzed with

relatively new analytical methods.

Some uncertainties can at least be defined, if not

reduced, through quality assurance/quality control

programs. QA/QC programs, which are part of

EPA’s contract analysis program, need to consider

sample handling and storage procedures, sample

preparation, care of equipment, methods for assessing data for completeness, and record-keeping and

documentation (ACS, 1980, 1982). Analysis of several samples is also important for obtaining statistically significant results. Other factors important

for obtaining meaningful analytical results in

groundwater contamination studies concern: the

laboratory certification process,l7 laboratory selection, availability of background information (e.g.

about sources and users), availability of information about the nature and history of the sample,

independent confirmation of the quality of 1aboratory data, and guidance on the selection of appropriate measurement methods (Woodward-Clyde

Consultants, 1983; Keith, et al., 1983).

38-799 0 - 84 - 6 : QL 3
138 ● Protecting the Nation’s Groundwater From Contamination

Photo credit: U.S. Environment/ ProtectIon Agency

Standard reference materials are provided by EPA’s Environmental Monitoring Laboratory to laboratories for instrument

calibration and internal checks in order to evaluate performance.

CHAPTER 5 REFERENCES

American Chemical Society (ACS), “Data Acquisition

and Data Quality Evaluation in Environmental

Chemistry, Analytical Chemistry 52:2242, 1980.

American Chemical Society, “Improving the Reliability

of and Acceptability of Analytical Chemical Data

Used for Public Purposes, ” Chemical Engineering

News 60(23):44, 1982.

Brass, H. J., “Procedures for Analyzing Organic Contaminants in Drinking Water, Journal American

Water Works Association, pp. 107-112, February

1982.

Chapman, P. M., G. P. Romberg, and G. A. Vigers,

“Design of Monitoring Studies for Priority Pollutants, ’’Journal of the Water Pollution Control Federation, vol. 54, No. 3, pp. 292-297, March 1982.

Davis, S., Environment Testing and Certification

Corp., personal communication, May 1984.

Environ Corp., “Approaches to the Assessment of

Health Impacts of Groundwater Contaminants, ”

draft report prepared for the Office of Technology

Assessment, Aug. 15, 1983.

Environmental Science and Technology, vol. 15, No,

6, 1982.

GeoTrans, Inc., “Technologies for a Hydrogeologic

Analysis-Interim Draft Report, ” draft report prepared for the Office of Technology Assessment,

1983a.

GeoTrans, Inc., ‘‘RCRA Draft Permit Writer’s Manual, Groundwater Protection, 40 CFR Part 264 Subpart F, ‘‘ U.S. EPA contract No. 68-01-6464, draft,

1983b.

Geraghty & Miller, Inc., “The Fundamentals of

Groundwater Quality Protection, ” New York, 1983.

Keith, S. J., L. G. Wilson, and H. R. Fitch, “Sources
Ch. 5—Hydrogeologic Investigations of Groundwater Contamination ● 139

of Spatial and Temporal Variability in Ground -Water Quality Data and Methods of Control: Case

Study of the Cortaro Monitoring Program, Arizona , in Second National Symposium on Aquifer

Restoration and Groundwater Monitoring, National

Watcr Well Association, Columbus, OH, pp. 217-

228, May 26-28, 1982a.

Keith, S.J., and 1,. G. Wilson, ‘‘ Stacking the Deck in

Ground-Water Quality Data, Proceedings of the

Arizona Section of the American Water Resources

Association Ground Water Quality Management

Symposium, Tucson, AZ, pp. 27-34, Oct. 29, 1982b.

Keith, S.J., M. T. Frank, G. McCarty, and G. Mossman, ‘ ‘Dealing With the Problem of Obtaining Accurate Ground-Water Quality Analytical Results,

Proceedings of the Third National Symposium on

Aquifer Restoration and Ground-Water Monitoring,

Columbus, OH, pp. 272-283, May 25-27, 1983.

McCarty, P., Stanford University, personal communication, July 17, 1984.

Miller, D., Testimony before the Toxic Substances and

Environmental Oversight, Committee on Environment and Public Works, U. S. Senate, July 28, 1982.

Miller, S.. “Quality Assurance, Analytical Methods,

and Hazardous Wastes, Environmental Science and

Technology, vol 16, No. 6, pp. 332A-336,4, 1982.

Neal, R. A., ‘‘ Drinking Water Contamination: Priorities for Analysis of Organics, Guest Editorial, vol.

17, No. 3, p. 11 3A, 1983.

Office of’ Technology Assessment, Use of Models for

Water Resources Management, Planning, and Pol -

icy, OTA-O - 159 Washington, DC: U.S. Govern -

ment Printing Office, August 1982).

Perry, R. H., and C. H. Chilton (eds. ), Chemical Engineers' Handbook, .5th cd. (New York: McGraw-Hill

Book Co., 1973).

Sax, N. 1., Dangerous Properties of Industrial

Materials, .5th cd. ( New York: Van Nostrand Reinhold, 1979).

Shifrin, N., Cambridge Analytical Associates, personal

communicant ion, Apr. 16, 1984.

Todd, D. K.. R. Al. Tinlin, K. D. Schmidt, and L.

G. Everett, ‘‘A Groundwater Quality Monitoring

Methodology, Journal American Water Works

Association, pp. 586-593, 1976.

U.S. Environmental Protection Agency, ‘‘Methods for

Chemical Analysis of Water and Waste," Environmental Monitoring and Support Laboratory (EMSL),

Cincinnati, OH, EPA-600/4-79-020, 1974, revised

March 1979.

U.S. Environmental Protection Agency, ‘‘Treatability

Manual, Office of Research and Development,

Washington, DC, EPA 600/2-82-001 (3 vols. ), September 1981.

U.S. Environmental Protection Agency, ‘ ‘Test Methods for Evaluating Solid Waste, Physical/Chemical

Methods (SW-846 ),” July 1982.

U.S. Environmental Protection Agency, ‘ ‘Methods for

Nonconventional Pesticides Chemicals Analysis of

Industrial and Municipal Wastewater," Effluent

Guidelines Division, Washington, DC, EPA 440/1 -

83/079-C, January 1983.

U.S. Geological Survey, ‘ ‘Laboratory Analysis, Book

5, Section A, Techniques of Water-Resources Investigations of the United States Geological Survey"

(Washington, DC: U.S. Government Printing Office, 1979).

Vicory, A. H., Jr., and J. F. Malina, Jr., ‘ ‘Apparatus

Needs and Costs for Monitoring Priority Pollutants,

Journal of the Water Pollution Control Federation,

vol. 54, No. 2, pp. 125-128, February 1982.

Weast, R. C. (cd.), Handbook of Chemistry and Physics, 59th ed. (West Palm Beach, FL: CRC Press,

Inc., 1978-79).

Windholz, M., S. Budavari, R. F. Blumetti, and E. S.

Otterbein (eds. ), The Merck Index—An Encyclopedia of Chemicals, Drugs, and Biological, 10th ed.

(Rahway, NJ: Merck & Co., Inc.l 1983).

Wood, E. F., R. A. Ferrara, W. G. Gray, and G. F.

Pinder, Groundwater Contamination From Hazardous Wastes (Englewood Cliffs, NJ: Prentice Hall,

Inc., 1984).

Woodward-Clyde Consultants, Inc., ‘ ‘Groundwater

Contaminants and Their Measurement, draft report prepared for the Office of Technology’ Assessment, October 1983.
Detection
Chapter 6

Federal Efforts To Detect

Groundwater Contamination
Contents

Pag e

Chapter Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . , 14.5

Chapter 6 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 161
Chapter 6

Federal Efforts To Detect

Groundwater Contamination

CHAPTER OVERVIEW

This chapter describes the investigatory activities of the Federal Government related to groundwater contamination. Some of these activities are

explicitly mandated by Federal legislation. Others

have been undertaken by Federal agencies either

to support regulatory programs or as special studies.

The techniques used for detection activities are discussed in chapter 5.

Four major types of Federal investigatory programs are discussed:

1.

2.

3.

4.

conducting hydrogeologic investigations of

aquifer systems, including ambient groundwater quality;

monitoring drinking water supply systems;

conducting inventories of potential sources of

contamination; and

monitoring groundwater in the vicinity of specific sources of contamination (includes:

monitoring conducted by Federal agencies

with respect to federally financed remedial action programs, hydrogeologic investigations,

special studies, and monitoring required

under regulatory programs that apply to facility owners or operators).

These programs are providing significant information on the Nation’s groundwater problems. However, their coverage is generally limited relative to

the sources of contamination and substances discussed in chapter 2. For example, only recently are

hydrogeologic investigations starting to look for

organic chemicals; monitoring provisions for drinking water supplies address only selected substances

found in public systems; inventories are conducted

for only particular sources; and monitoring requirements are specified for only particular sources and

their coverage is inconsistent.

The chapter begins with an overview of U.S.

Geological Survey (USGS) activities. Although

USGS does not have regulatory authority with respect to groundwater contamination, hydrogeologic

information developed by its Water Resources Division supports the programs of other Federal agencies as well as State and local governments.

GROUNDWATER ACTIVITIES OF THE

U.S. GEOLOGICAL SURVEY

Principal responsibility in the Federal Govern- Program, and 3) activities for other Federal

ment for-providing hydrogeologic information and agencies.

appraising the Nation’s water resources lies within

the Water Resources Division of the USGS. 1 The

division conducts three types of programs: 1) Fed- Federal Programs

eral programs, 2) the Federal-State Cooperative

Congressional appropriations for USGS support

‘USGS was established by legislation passed in 1879 (see 43 U.S. C.

31 et seq ). Subsequent legislation specifically authorized USGS to

activities on research, data collection, high-priority

gaug-c streams and dcterm ine the Nation water supply. For an over- special topics, and coordination of Federal use and

. .

view of all L’SGS activit ics sec Chase, ct al., 1983. acquisition of water data.

145
146 ● Protecting the Nation’s Groundwater From Contamination

Examples of programs related to groundwater

quality include the Regional Aquifer-System

Analysis Program, the Toxic Wastes-Groundwater Contamination Program, the Radioactive Waste

Program, and the Coal Hydrology and Oil Shale

Hydrology Programs. In addition, USGS maintains

the National Water-Data Exchange (NAWDEX)

and is involved in research efforts related to groundwater contamination (see ch. 3).

Federal-State Cooperative Program

The Federal-State (Inoperative Program encompasses hydrologic data collection and water resources investigations relevant to State and local

needs and issues. Congressional appropriations support the program, and the States are required to

match Federal funds on a 50-50 basis. USGS considers this program ‘‘the foundation of much of the

water-resources management and planning activity in the Nation and it serves as an early warning

system for the detection of emerging water problems’ (USGS, 1982). The program is active in all

50 States, Puerto Rico, Virgin Islands, Guam,

and the Trust Territories; and during 1982, USGS

had agreements with more than 800 State and local

agencies (at a total funding of more than $80 million). Of these projects, 414 were at least partly

related to either groundwater quality or quantity.

The total budget for the groundwater portions of

the investigations was $25 million (USGS, 1982;

Chase, et al., 1983).

Activities for Other Federal Agencies

USGS also provides hydrologic expertise and related information to other Federal agencies upon

request. The agencies are generally required to

reimburse USGS. Programs established through

Interagency Agreements and Memoranda of Understanding are included in this category (see ch.

3). In 1982, USGS undertook 115 projects at least

partly related to groundwater for other Federal

agencies. The total budget for the groundwater portion of these projects was $5,5 million (USGS,

1982).

INVESTIGATIONS OF AQUIFER SYSTEMS AND

AMBIENT GROUNDWATER QUALITY

Section 104(a)(5) of the Clean Water Act specifies

that EPA shall,

. . . in cooperation with the States, and their political subdivisions, and other Federal agencies

establish, equip, and maintain a water quality surveillance system for the purpose of monitoring the

quality of the navigable waters and groundwaters . . . [emphasis added].

As noted above, USGS is responsible for collecting most of the Nation’s water quality data. It operates two nationwide surface water monitoring programs: the National Stream Quality Accounting

Network (NASQAN) and the National Hydrologic

Benchmark Network.2 Fundamental differences bez

r

I’he NASQAN pr~rarn is cornpr]sed of 504 operating stations designed to monitor the quantity and quality of water in major U.S.

rivers. The National Hydrologic Benchmark Network monitors hydrologic characteristics of 52 small drainage basins that are relati~”ely

unaffected by human activities. Data collected from these programs

are stored in computer systerls maintained by USGS and EPA.

tween surface water and groundwater have precluded the establishment of a similar nationwide

program for the collection of groundwater data. For

example, there is no single point in an aquifer from

which ‘ ‘upstream’ water quality can be deduced,

as in river basins.

Although there is no nationwide groundwater

data collection program, groundwater studies have

been conducted by numerous Federal, State, and

local agencies. 3 The data collected relate to sitespecific conditions and the characterization of certain aquifers. Historically, the studies have focused

on certain inorganic compounds; only recently have

hydrogeologic investigations of specific instances of

3Therc were 28,964 active obser~’ations by Federal agencies at

groundwater stations in 1968 (see Langford, 1977). In 1982, groundwater quality data were collected at more than 7,000 stations through

the Federal-State Cooperative Program and other L’SGS activities (see

Chase, et al,, 1983, p. 34).
Ch. 6—Federal Efforts To Detect Groundwater Contamination ● 147

contamination started to provide some information

on organic chemicals in groundwater. In recognition of these data gaps, USGS is currently involved

in a program to characterize the Nations major

aquifer systems and will begin to monitor ambient

groundwater in selected areas of the United States

in 1984.

Regional Aquifer-System Analysis

Program

In 1978, USGS began a series of studies to provide basic information about certain regional

groundwater systems that comprise a significant

portion of the Nation’s water supply. The Regional

Aquifer-System Analysis (RASA) Program has

identified 28 systems for possible study. Types of

information being developed include: characteristics of the flow system; general water quality; regional utilization patterns; and response of aquifer

systems to stress. Computer simulation models are

being developed for each system to assist in understanding the natural flow regime and changes resulting from human activities and in predicting the

effects of future stresses (e. g., waste disposal, artificial recharge, and pumping). The status of RASA

studies as of September 1984 is shown in figure 3.

The RASA studies are conducted on a very large

scale and contribute only indirectly to site investigations of groundwater contamination by providing

a framework for model selection and analysis. Studies conducted as part of the Federal-State Cooperative program provide more detailed information

about local areas within the regional systems.

Ambient Groundwater Quality

Appraisal

USGS is initiating an ambient groundwater quality study that will emphasize detection of organic

chemicals and trace metals. Representative areas

of the United States will be selected on the basis

of climate, hydrogeology, land use, and other factors. A sampling network will be designed for each

area, both with samples taken first at a reconnaissance level and then at a more detailed level

(Cohen, 1983).

MONITORING DRINKING WATER SUPPLIES

Public Water Systems

Part B of the Safe Drinking Water Act (SDWA)

establishes a program to ensure that public drinking water supply systems comply with minimum

national standards for substances that may adversely affect human health. The requirements apply to both surface water and groundwater. Section 141 requires the Environmental Protection

Agency (EPA) to promulgate National Drinking

Water Regulations that specify either Maximum

Contaminant Levels (MCLs) or treatment techniques for such substances. (See app. C. 3 for a

listing of standards for specific substances and other

quality indicators. )

The act also provides for the establishment of an

enforcement program for public water systems. Under Section 1413, a State may assume primary enforcement responsibility if it:

1.

2.

3.

4.

5.

adopts drinking water regulations at least as

stringent as the Federal regulations;

adopts and implements adequate enforcement

procedures;

complies with EPA record-keeping and reporting requirements;

permits variances or exemptions based on conditions at least as stringent as the Federal requirements (Sections 1415 and 1416 of SDWA

allow for variances and exemptions, respectively, from the drinking water regulations if

such action would not pose an unreasonable

risk to health); and

adopts and implements an adequate plan for

provision of safe drinking water under emergency circumstances.

Ch. 6—Federal Efforts To Detect Groundwater Contamination ● 149

As of September 1984, 52 out of the 57 States and

Territories covered by the program had accepted

primacy for public water supply systems (Baltay,

1984). 4 EPA is responsible for enforcing the regulations when a State does not assume primacy.

The Safe Drinking Water Act defines a public

water system as ‘‘a system for the provision to the

public of piped water for human consumption, if

such system has at least 15 service connections or

regularly serves at least 25 individuals. The Safe

Drinking Water Act does not address individual

drinking water supplies (e.g., private domestic

wells). EPA estimates that there are approximately

12-14 million individual private wells in the United

States supplied by groundwater (EPA, 1983a).

Public water systems are further divided into

‘‘community’ and ‘ ‘non-community’ systems by

4 l)ri m.ic y has not ken a( ccpted b} the Ilist ri( t of (;olurnbia, I nd i-

,ina, P(, nnsyl\an ia, Orcgmn, or W’yorning ( Pcnns~l\ania is expcctcd

[() [I(I s() in 1 98.5) (13altay, 1984) ‘1’erri[orie\ under EPA jurisdiction

arc Ameri( arl Samoa, (;uam, ?J(Jrt hem hlarianas, Puerto RICO, Trust

‘1’crrit[)rics, ,int] L’. S. \’ir~in Jslar](l\.

‘Section 1 401(4), $2 U .S C; 300(f)(4).

EPA regulations. G ‘ ‘Community’ systems serve at

least 15 connections year-round or regularly serve

at least 25 people. ‘‘ Non-community’ systems

serve transient users, such as at highway rest stops

or campgrounds, and are not required to comply

with the standards for organic chemicals. 7 The

States may also decide that non-community systems

not be required to meet the nitrate standard; nonetheless, concentrations may not exceed a specified

level.8 A recent EPA inventory indicates that there

are 59,660 community systems and approximately

160,000 non-community water supplies (Kimm,

1983).

EPA Drinking Water Surveys

EPA’s Office of Drinking Water and Office of

Research and Development have conducted a num6

40 CFR 141 .2(c).

7

40 CFR 141.12.

8

40 CFR 141.1 1(d). The water supplier must demonstrate that the

water will not be a~’ailable to children under the age of 6; that use

of the water will not ~’suit in adl’crse health effects; that there will

be public notification of the levels; and that the local and State officials will be notifrcd of levels exceeding the national standard.

Photo credit: State of Florida Department of Environmental t3egu/atiorr

There are 12-14 million individual private wells in the United States used for drinking water; these wells are not covered

by SDWA. Shown here are the pump and storage tank for a private well.
150 ● Protecting the Nation’s Groundwater From Contamination

ber of surveys of drinking water supplies to provide

data to support regulatory actions under SDWA

(e. g., development of MCLs). These surveys include: the National Organic Reconnaissance Survey (1975, focused primarily on surface water); the

National Organics Monitoring Survey (conducted

1976-77); the Rural Water Survey (conducted

1978-79); the Community Water Supply Survey

(1978); and the Groundwater Supply Survey (conducted 1980-81) (see ch. 2 for additional information), EPA initiated a survey in July 1984 to collect necessary information about the nationwide

occurrence of selected inorganic contaminants and

radionuclides in community drinking water supplies (EPA, 1983b); results are not expected to be

available before 1986 (Westrick, 1984).

SOURCE INVENTORIES

The Federal Government is also involved in investigatory efforts concerning specific sources of

known or potential groundwater contamination.

Activities related to the compilation of information

on locations and characteristics of actual or potential sources are generally referred to as inventories.

Inventories provide one indication of the extent to

which particular sources are or may be contributors

to contamination problems.

Federal inventory activities are of three types:

1.

2.

3.

Federal statutes authorize the use of funds to

support formal studies or projects involving

the collection of information from, for example, Federal, State, and local government files

and records, field investigations, and aerial

photography;

Federal statutes or regulatory programs establish requirements for the submission of information on spills, accidents, or other releases

of contaminants that have the potential to

enter groundwater; and

Federal regulations require responsible parties to submit information about particular

sources.

These inventories focus on selected sources in OTA

Categories I, II, and 111 (namely, sources designed

to discharge substances; sources designed to store,

treat, and/or dispose of substances; and sources that

transport or transmit substances; see ch. 2, table

5). There are no explicit inventory provisions for

sources in OTA Categories IV, V, and VI (namely,

sources discharging substances as a consequence

of other planned activities; sources that provide conduits for or induce discharges of substances; and

naturally occurring sources).

Formal

The Resource Conservation and Recovery Act

(RCRA) and the Safe Drinking Water Act

(SDWA) contain provisions authorizing the use of

Federal funds to conduct formal studies that involve

the collection of information about particular

sources—open dumps, hazardous waste sites, and

surface impoundments.

Open Dumps

Section 4005(b) of RCRA requires EPA to publish an inventory of all open dumps in the United

States. The States were to conduct the inventory

on the basis of specific criteria developed by EPA

for classifying solid waste facilities as sanitary landfills or open dumps, and the inventory was to be

completed no later than 1 year after promulgation

of the criteria. The criteria were published in 1979

(with subsequent amendments in 1981), almost 2

years later than the date specified by the statute. g

EPA first published its inventory in 1981. It listed

1,209 open dumps; 80 of them were cited as having violated the groundwater requirements specified in the criteria. However, a General Accounting Office (GAO) study indicated that the 1981

inventory was based on incomplete reports from

the States (GAO, 1981).

‘RCRA specifies that a facility may be classified as a sanitary landfill

‘ ‘only if there is no reasonable probability of adverse effects on health

or the environment from disposal of solid waste at such facility’ [42

~’. S.C. 6944(a)]. Criteria established by EPA specify eight conditions

that must be met by a facility in order to be classified as a sanitary

landfill; onc of the criteria requires that a facility not contaminate an

underground drinking water source beyond the facility boundary or

an alternatiic boundary (set on a case-b}’-case basis). See 40 CFR

257.3,
Ch. 6—Federal Efforts To Detect Groundwater Contamination ● 151

. .

.

●

✌

=

. .

Open

Photo credit: u.S. Environmental Protection Agency

dumps and their potential for groundwater contamination have been partially inventoried by the States

but inventories have not been completed due to inadequate funding from EPA.

The inventory was published a second time in

1982, to reflect State efforts during 1981. The third

edition of the inventory, published in 1983, incorporated both additions and deletions submitted by

18 States during 1982 (EPA, 1983c). The third edition contains 2,081 facilities; 130 violations of

EPA’s groundwater criteria were reported. EPA

estimates that these figures are based on evaluation of only 3 percent of the more than 300,000 solid

waste facilities in the United States (Absher, 1983).

A major problem encountered by the States with

respect to completion of the inventory has been the

lack of financial assistance from EPA. No Federal

funds for Subtitle D programs were made available

during 1982 and 1983, although funding was originally planned to extend through 1984 (EPA,

1983c).

Hazardous Waste Sites

The 1980 amendments to RCRA added Section

3012, which requires each State to, “as expeditiously as practicable, undertake a continuing program

to compile, publish, and submit . . . an inventory

describing the location of each site within such State

at which hazardous waste has at any time been

stored or disposed of."10 Although Section 3012 also

provides for Federal financial assistance to the

States, funds were not appropriated until September 1982, when $10 million was appropriated from

the Hazardous Substance Response Trust Fund

under the Comprehensive Environmental Resource,

Compensation, and Liability Act (CERCLA).11

1042 U S.C 69:12,

L 1 &,c public 1,al$. 97.272, Appmprl~t ionj .Act for the Eni’ironmc’ntd

Protection Agency, Sept. 30, 1982
152 Ž Protecting the Nation’s Groundwater From Contamination

Funds were allocated to the States in proportion

to the number of sites listed in EPA’s hazardous

waste site inventory as of January 17, 1983.

In addition to State inventories, some Federal

agencies have undertaken or have proposed inventories on Federal lands. For example, the Department of Defense conducted record searches of its

installations to identify hazardous waste sites. As

of August 10, 1983, 781 (out of911 ) searches were

completed (Daley, 1983). The Fish and Wildlife

Service recently requested all field stations to inventory all lands and facilities (Hester, 1983); and

the Bureau of Land Management is developing a

strategy to conduct hazardous waste site inventories

(Lawton, 1983).

Surface Impoundments

Section 1442(b)(3)(C) of the Safe Drinking Water Act allows EPA to award grants and enter into

contracts with any public agency, educational institution, or other organization to develop and expand the capability of States and municipalities to

carry out the purposes of the statute. In 1978, EPA

made $5 million available to the States to conduct

studies to assess the magnitude and potential effects of surface impoundments on groundwater

quality. Although a draft report was issued in 1982

on the results of the assessment, a final report has

not yet been issued by 13 PA. Subsequent drafts have

been issued; the most recent is dated July 1983.

The objectives of the studies were: to locate and

count the number of surface impoundments in the

United States and its Territories; to provide a first

approximation of the groundwater pollution potential of the impoundments; to assist the States and

EPA in developing a better understanding of the

problems caused by surface impoundments; and to

provide a data base upon which Federal (e.g., EPA)

and State authorities could develop a strategy to

control or regulate pollution from these sources, including to recommend legislative programs, if necessary (EPA, 1983d).

The States located 180,973 surface impoundments used for industrial, municipal, agricultural,

mining, and oil and gas extraction purposes. 13 EPA

“48 FR 5686.

i +S{lnlc . S[att.s ~ls[) ~eportcd (In other types of impoundments such

as septic systetns, farm ponds used for stock watering, and safety impoundments around bulk sto~ ge tanks.

concluded from the studies that fewer than 10 percent of all sites are located in a manner that poses

little threat of groundwater contamination, and approximately 85 percent of all sites are located within

1 mile of a potential surface or groundwater source

(EPA, 1983d). (See ch. 2 and app. A.5 for further

information on surface impoundments. )

Reporting Requirements

Four Federal statutes and their associated regulatory programs require notification of EPA or the

Department of Transportation (DOT) in the event

of a spill, accident, or other release of specified contaminants. The relevant statutes are the Clean Water Act and CERCLA for EPA; and the Hazardous Liquid Pipeline Safety Act (HLPSA) and the

Hazardous Materials Transportation Act (HMTA)

for DOT. Although reporting activities are not

inventories in the strict sense, they do provide

documentation on releases of substances from various sources. But, with the exception of CERCLA,

the emphasis of reporting requirements is on surface water discharges, not groundwater. In addition, the programs address different substances; although there is some overlap, each agency has

developed its own list of contaminants that it considers hazardous.

EPA Regulations: CWA and CERCLA

Section 311 of the Clean Water Act (CWA) requires individuals in charge of facilities or vessels

to notify the National Response Center in the event

of any discharge of oil or a hazardous substance

into navigable waters, along adjoining shorelines,

or into waters of the contiguous zone. The National Response Center is operated by the U.S.

Coast Guard in Washington, DC. Its function is

to convey information about releases of oil and hazardous substances to the appropriate government

agencies so that they, in turn, can determine

whether and how response action should be taken.15

Although Section 311 relates to surface water dis14Section 3 I I@)(2)(A) requires EPA to promulgate regulations listing

the hazardous substances that are subject to this section. These substances are listed in 40 CFR 116. Section 31 l(b)(4) requires the determination of quantities of oil and hazardous substances, discharge

of which may be harmful to public health or welfare. 40 CFR 117

specifies the quantities.

1540 CFR 300.36.
Ch. 6—Federal Efforts To Detect Groundwater Contamination ● 153

charges, it is significant here to the extent that there

may be a connection between surface water and

groundwater.

CERCLA contains a provision that is similar to

Section 311 of CWA, but it is explicitly applicable

to groundwater as well as surface water. Section

103(a) requires individuals in charge of facilities or

vessels to notify the National Response Center in

the event of any release of any hazardous substances

in quantities equal to or greater than specified

amounts. 16 The definition of the term ‘‘release’

encompasses: spilling, leaking, pumping, pouring,

emitting, emptying, discharging, injecting, escaping, leaching, dumping, or disposing into the environment.17 In addition, Section 103(c) of CERCLA

required individuals to notify EPA of the existence

of any unauthorized hazardous waste facilities by

June 1981. The sites identified are part of EPA’s

inventory of hazardous waste sites.

DOT Regulations: HLPSA and HMTA

Under regulations promulgated by DOT for

pipelines and transportation-related sources, all carriers are required to submit written reports to DOT

describing any accidents within 15 days of their

discovery. DOT prepares annual reports which

summarize the information reported under these

regulations. (See app. A.5 for data on numbers of

accidents from these reports. )

DOT regulations under HLPSA specify that any

failure in a pipeline system must be reported if the

release of a hazardous liquid (defined as petroleum,

petroleum products, or anhydrous ammonia) results in: 1) an explosion or fire not intentionally

set by the operator; 2) loss of 50 or more barrels

of liquid; 3) escape to the atmosphere of more than

5 barrels a day of highly volatile liquids; 4) the death

of anyone; 5) bodily harm to anyone; or 6) estil’L’nder CERCI,A, the term ‘‘hazmfous substances’ includes those

substances ct]~cred h} Se( tions 311 (b)(2)(A) and 307(a) of CWA, Section 102 of CER[; I.A, Section 3001 of RCRA, Section 112 of the

Clean Alr Act, and Sm-tion 7 of ‘1’SCA. Se(tion 102(a) of CIERC IA

reyu i res F-PA to designate hazardous substances (in add it ion to those

spcclfied abo~x- ) and to establish reportable quant it ics for them, Section 102(b) specifics that a reportable quantity of 1 pound shall apply

to all the haza~iou$ substances includccl in the statutes 1 isted abm’c

(ex( ept for differ-ent quantltie~ established under Section 31 l(b)(4) of

CWA) unless and until F,P.A estahlishcs reportahlc quantitt regulations pursuant to %ction 1 02(a).

1

‘SC( t ion 101 (22)

mated damage to the property of the operator or

others, or both, exceeding $5,000.18 In cases of significant damage, DOT must be notified immediately by telephone. Criteria for such instances include, but are not limited to, accidents resulting

either in damage exceeding $5,000 (as above) or

in the ‘‘pollution of any stream, river, lake, reservoir, or other similar body of water that violated

applicable water quality standards, caused discoloration of the surface of the water or adjoining

shoreline, or deposited a sludge or emulsion beneath

the surface of the water or on adjoining shorelines. ”19 Similar conditions for groundwater are not

specified,

DOT regulations for HMTA contain similar

provisions. The hazardous materials coverage is extensive.20 DOT must be notified by telephone at

the earliest practicable moment after any incident

in which: 1) a person is killed; 2) a person receives

injuries requiring hospitalization; 3) estimated damage to the carrier or other property exceeds $50,000;

4) fire, breakage, spillage, or suspected radioactive

contamination involving shipment of radioactive

material occurs; 5) fire, breakage, spillage, or suspected contamination involving shipment of etiologic agents occurs; or 6) in the judgment of the

carrier, the situation should be reported .21 In the

event of a discharge of a reportable quantity of a

hazardous substance into navigable waters or along

adjacent shorelines, the National Response Center must be notified (see the discussion under CWA

above). As is true for the pipeline requirements,

no reporting requirements are tied to groundwater

contamination other than the property

visions.

Regulatory Requirements

to Inventories

damage proRelated

Part C of SDWA requires EPA to establish regulations specifying minimum requirements for State

Underground Injection Control (UIC) Programs.

1849 c FR 195,50. A spe(ial accident reporting form has been d(.-

~clop~d b~ DOT (110’1’ Form 7000-1).

1949 c FR 19.5. 52(a).

‘“See 49 C FR 172

z 14q c FR 171 15, 1)0”1’ F{)rnl F 5800, 1 must also be submit te(l

within 15 days of disco~ery of the accident (see 4° (~ FR 171. 16).

38-799 0 - 84 - 7 : QL 3
154 • Protecting the Nation’s Groundwater From Contamination

Final Federal regulations were published on Feb- by rule to submit inventory information to the

ruary 3, 1982, and the States are now in the proc- States or EPA about their operations within one

ess of developing UIC programs based on these re- year after they are authorized. The inventory form

quirements. The States are required to establish a requires information on the facility name and locapermitting program for injection wells. Most exist- tion, a legal contact, ownership, the nature and type

ing wells are authorized by rule until a State pro- of wells, and the operating status of the wells .22

gram is in place and site-specific permits are issued.

One section of the Federal regulations requires

owners and operators of injection wells authorized ‘Z40 CFR 144.26.

.

Photo credit: State of Florida Depatiment of Environmental Regulation

Permitting rules developed under State Underground Injection Control Programs typically address

the construction and monitoring of injection wells. - -‘ -
Ch. 6—Federal Efforts To Detect Groundwater Contamination ● 155

GROUNDWATER MONITORING AND SOURCES

This section summarizes Federal efforts related

to monitoring specific sources of groundwater contamination. Three types of monitoring activities are

discussed:

1. monitoring requirements specified by Federal regulations that apply to facility owners and

operators;

2. monitoring conducted by Federal agencies

relative to federally funded remedial programs; and

3. monitoring conducted by Federal agencies as

part of hydrogeologic investigations related to

certain sources.

Table 30 summarizes these groundwater monitoring activities as they relate to Federal statutes and

indicates the objectives of each program. Appendix

E contains more detailed information about these

activities for each source. In addition to the statutory provisions shown in table 30, other Federal

groundwater monitoring activities are also described below.

In summary, Federal monitoring requirements

are specified for certain sources in OTA Categories 1, II, IV, and V (see ch. 2, table 5). But there

are inconsistencies in the coverage of the monitoring provisions for similar sources under different

programs. Detailed guidance on the design of sitespecific monitoring systems is not provided in the

regulations. Although guidance manuals have been

developed by some agencies, the individuals who

draft and review permits (including exemptions)

are responsible for ensuring the adequacy of sitespecific systems; adequately trained personnel are

in short supply. A detailed discussion of these conclusions follows.

Monitoring Provisions of

Federal Programs

There are 10 regulatory programs authorized by

Federal statutes that establish groundwater monitoring provisions for sources of contamination.

However, these programs address only certain

sources in OTA Categories I, 11, IV, and V, and

monitoring is not required for many of them. For

example, there are no requirements for non-point

sources in Category IV such as irrigation practices

and fertilizer applications. Groundwater monitoring requirements are not established for any

sources in Categories III and VI.

In addition, monitoring requirements for

sources within the same category are not uniform.

Under the Toxic Substances Control Act (TSCA),

for example, required groundwater monitoring for

PCB disposal sites is limited to an initial collection

of background data. In contrast, the regulations

promulgated for radioactive disposal sites under the

Atomic Energy Act (AEA) and for hazardous waste

sites under the Resource Conservation and Recovery Act (RCRA) require monitoring during operation and after closure.

For the most part, final Federal regulations do

not contain explicit monitoring requirements (e. g.,

numbers and locations of wells) in recognition of

the site-specific nature of groundwater contamination problems and the technical uncertainties associated with hydrogeologic investigations (see ch. 5).

Because of the variety and complexity of factors that

must be considered in designing a program to monitor (e. g., sample and analyze) groundwater quality, Federal regulations establish monitoring objectives and general guidelines rather than detailed

requirements. 23

In the absence of detailed monitoring requirements, several Federal agencies have developed

manuals to assist both permit (or license) writers

and the regulated community. 24 The manuals provide guidance on determining background levels,

selecting parameters, designing a monitoring network (e. g., number and location of wells), selecting appropriate sampling frequencies, and other

topics. Because monitoring programs do not specify

detailed requirements, the burden of ensuring that

Z~scC. ~, ~,, Fi~~ N~~ Rcwla[ ions ~Or 1.o\\I Lrvcl Radioact i~’e \$’astt’

Disposal Facilities, 47 FR 57452, Dec. 27, 1982; Final OShl Rc’~ulationj for Surface Coal hlining and Rcrlamat ion Opm-ations, 48 FR

43974, Scpt. 26, 1983; and Final EPA Rc~ulations for Hazardous

J$’astc I,and Disposal Facilities, 47 FR 32274, July 26, 1982,

24 ~’~~r ~.~amp]~., s{>c FYJ4, 1983c,, 1983f; and NRC, 1983a, 1983t~.
Table W.—Federal Groundwater Monitoring Provisions and Objectives

Statutory authority Monitoring provisionsa Monitoring objectives

Atomic Energy Act

Clean Water Act

—Sections 201 and 405

—Section 208

Coastal Zone Management Act

Comprehensive Environmental

Response, Compensation,

and Liability Act

Federal Insecticide, Fungicide,

and Rodenticide Act—

Section 3

Federal Land Policy and

Management Act (and

Associated Mining Laws)

Hazardous Liquid Pipeline

Safety Act

Hazardous Materials

Transportation Act

National Environmental

Policy Act

Reclamation Act

Resource Conservation and

Recovery Act

Groundwater monitoring is specified in Federal regulations for low-level radioactive

waste disposal sites. The facility license must specify the monitoring requirements

for the source. The monitoring program must include:

—Pre-operational monitoring program conducted over a 12-month period. Parameters not specified.

—Monitoring during construction and operation to provide early warning of releases

of radionuclides from the site Parameter and sampling frequencies not

-

specified.

—Post-operational monitoring program to provide early warning of releases of radionuclides from the site. Parameters and sampling frequencies not specified.

System design is based on operating history, closure and stabilization of the site.

Groundwater monitoring related to the development of geologic repositories will be

conducted. Measurements will include the rate and location of water inflow into

subsurface areas and changes in groundwater conditions.

Groundwater monitoring may be conducted by DOE, as necessary, part of remedial

action programs at storage and disposal facilities for radioactive substances.

Groundwater monitoring requirements are established on a case-by-case basis for the

land application of wastewater and sludge from sewage treatment plants.

No explicit requirements are established; however, groundwater monitoring studies

are being conducted by SCS under the Rural Clean Water Program to evaluate the

impacts of agricultural practices and to design and determine the effectiveness

of Best Management Practices.

The statute does not authorize development of regulations for sources. Thus, any

groundwater monitoring conducted would be the result of requirements established

by a State plan (e.g., monitoring with respect to salt-water intrusion) authorized and

funded by CZMA.

Groundwater monitoring may be conducted by EPA (or a State) as necessary to

respond to releases of any hazardous substance+ contaminant, or pollutant (as

defined by CERCLA).

No monitoring requirements established for pesticide users. However, monitoring may

be conducted by EPA in instances where certain pesticides are contaminating

groundwater. b

Groundwater monitoring is specified in Federal regulations for geothermal recovery

operations on Federal lands for a period of at least one year prior to production.

Parameters and monitoring frequency are not specified.

Explicit groundwater monitoring requirements for mineral operations on Federal lands

are not established in Federal regulations. Monitoring may be required (as a permit

condition) by BLM.

Although the statute authorizes development of regulations for certain pipelines for

public safety purposes, the regulatory requirements focus on design and operation

and do not provide for groundwater monitoring.

Although the statute authorizes development of regulations for transportation for

public safety purposes, the regulatory requirements focus on design and operation

and do not provide for groundwater monitoring.

The statute does not authorize development of regulations for sources.

No explicit requirements established; however, monitoring may be conducted, as

necessary, as part of water supply development projects.

Groundwater monitoring is specified in Federal regulations for all hazardous waste

land disposal facilities (e.g., landfills, surface impoundments, waste piles, and

land treatment units).

to obtain background water quality data and to evaluate

whether groundwater is being contaminated.

To confirm geotechnical and design parameters and to

ensure that the design of the geologic repository

accommodates actual field conditions.

To characterize a contamination problem and to select and

evaluate the effectiveness of corrective measures.

To evaluate whether groundwater is being contaminated.

To characterize a contamination problem and to select and

evaluate the effectiveness of corrective measures.

To characterize a contamination problem (e.g., to assess

the impacts of the situation, to identify or verify the

source(s), and to select and evaluate the effectiveness of

corrective measures).

To characterize a contamination problem.

To obtain background water quality data.
Table 30.—Federal Groundwater Monitoring Provisions and Objectives—continued

Statutory authority Monitoring provisions Monitoring objectives

Resource Conservation and I t ’

Recovery Act (cent’d) These requirements specify the installation of at least one upgradient well and

–Subtitle C three downgradient wells. Samples must be taken quarterly during the first year and

analyzed for the National Interim Drinking Water Regulations, water quality indicator

parameters (chloride, iron, manganese, phenols, sodium, and sulfate), and indicator

parameters (pH, specific conductance, TOG and TOX). In subsequent years,

each well is sampled and analyzed quarterly for the six background water quality

indicator parameters and semiannually for the four indicator parameters.

Groundwater monitoring requirements can be waived by an owner/operator if a

written determination indicating that there is low potential for waste migration via

the upper-most aquifer to water supply wells or surface water is made and certified

by a qualified geologist or engineer. The determination is not submitted to EPA

for verification or approval.

The monitoring requirements for a fully permitted facility are comprised of a three-part

program:

—Detection Monitoring — Implemented when a permit is issued and there is no

indication of leakage from a facility. Parameters are specified in the permit.

Samples must be taken and analyzed at least semiannually. Exemptions from

detection monitoring program may be granted by the regulatory authority

for landfills, surface impoundments, and waste piles with double liners and

leak detection systems.

—Compliance Monitoring — Implemented when groundwater contamination is

detected. Monitoring is conducted to determine whether specified concentration

levels for certain parameters are being exceeded (levels are based on background

concentrations, maximum contaminant levels specified by the National Drinking

Water Regulations [if higher than background], or an alternative concentration

limit [established on a site-specific basis]). Samples must be taken and analyzed

at least quarterly for parameters specified in the permit. Samples must also

be analyzed for a specific list of 375 hazardous constituents (Appendix Vlll,

40 CFR 261) at least annually.

—Corrective Action Monitoring – Implemented if compliance monitoring indicates

that specified concentration levels for specified parameters are being exceeded

(and corrective measures are required). Monitoring must continue until specified

concentration levels are met. Parameters and monitoring frequency not specified.

—Exemption from groundwater monitoring requirements may be granted by the

regulatory authority if there is no potential for migration of liquid to the

uppermost aquifer during the active life and closure and post-closure periods.

—Subtitle D Groundwater monitoring may be required by State solid waste programs. Federal

requirements for State programs recommend the establishment of monitoring

requirements.

Safe Drinking Water Act

—Part C—Underground Groundwater monitoring requirements may be specified in a facility permit for

Injection Control Program injection wells used for in-situ or solution mining of minerals (Class Ill wells) where

injection is into a formation containing less than 10,000 mg/l TDS. Parameters and

monitoring frequency not specified except in areas subject to subsidence or

collapse where monitoring is required on a quarterly basis.

Groundwater monitoring may also be specified in a permit for wells which inject

beneath the deepest underground source of drinking water (Class I wells).

Parameters and monitoring frequency not specified in Federal regulations.

To obtain background water quality data and evaluate

whether groundwater is being contaminated.

To obtain background water quality data or evaluate

whether groundwater is being contaminated (detection

monitoring), to determine whether groundwater quality

standards are being met (compliance monitoring), and to

evaluate the effectiveness of corrective action measures.

To evaluate whether groundwater is being contaminated.
Table 30.— Federal Groundwater Monitoring provisions and Objectives—continued

Statutory authority Montoring provisions Monitoring objectives

Surface Mining Control and Groundwater monitoring is specified in Federal regulations for surface and underReclamation Act ground coal mining operations to determine the impacts on the hydrologic balance

of the mining and adjacent areas. A groundwater monitoring plan must be

developed for each mining operation (including reclamation). At a minimum,

parameters must include total dissolved solids or specific conductance, pH, total

iron, and total manganese. Samples must be taken and analyzed on a quarterly

basis.

Monitoring of a particular water-bearing stratum may be waived by the regulatory

authority if it can be demonstrated that it is not a stratum which serves as an

aquifer that significantly ensures the hydrologic balance of the cumulative

impact area.

Toxic Substance Control Act

—Section 6 Groundwater monitoring specified in Federal regulations requires monitoring prior to

commencement of disposal operations for PCBs. Only three wells are required if

underlying earth materials are homogeneous, impermeable and uniformly sloping in

one direction. Parameters include (at a minimum) PCBs, pH, specific conductance,

and chlorinated organics. Monitoring frequency not specified.

No requirements are established for active life or after closure.

Uranium Mill Tailings Federal regulatory requirements for active mill tailings sites are, for the most part, the

Radiation Control Act same as those established under Subtitle C of RCRA.C

Groundwater monitoring for inactive sites may be conducted if necessary to determine the nature of the problem and for the selection of an appropriate remedial

action.

Water Research and The statute does not authorize the development of regulations for sources.

Development Act Groundwater monitoring may be conducted as part of projects funded by the act.

To obtain background water quality data and evaluate

whether groundwater is being contaminated.

To obtain background water quality data

To obtain background water quality data, evaluate whether

groundwater is being contaminated, determine whether

groundwater quality standards are being met, and

evaluate the effectiveness of corrective action measures.

To obtain background water quality data and to characterize

a contamination problem.

a The ~onltori

ng Provisions presented in this table are either those specified by regulatmns for exlstlng and new sources; or for groundwater monitoring that may be conducted as Part of an lnvesti9atoW study or remedial

b~~~~~i$~o~~n~jacturers may be required by EpA t. subm{t g~oundwater monitoring data as pafi of the registration requirements for a pestlclde product to evaluate the potentlat for a pesticide tO COntaf_Ilinate groundwater.

csee app. E.2 for a surnma~ of the differences between UMTRCA and RCFtA rnOnitOrh9 rfWJirernents.

SOURCE Office of Technology Assessment,
Ch. 6—Federal Efforts To Detect Groundwater Contamination ● 159

1

-

---- - -

- - - -

------ 

100 feet

Level of contamination ug/l (ppb):

❑ >100,000 10,000-100,000 1,000-10,000 100-1,000

n

1-100

Cred/t Tewhey, et al , 7982

The site-specific nature of groundwater contamination problems requires that hydrogeologic investigations be tailored

to site conditions. At this site, the design of the monitoring system provided data that were used for determining

the vertical distribution of volatile organic chemicals.

site-specific monitoring satisfies program objectives

lies with the individuals responsible for drafting and

approving facility permits and licenses.

Although monitoring requirements generally

lack specificity, some Federal regulations contain

more detailed requirements than others. For example, the regulations developed under the Surface Mining Control and Reclamation Act

(SMCRA) and TSCA specify the minimum parameters that must be measured; and RCRA (Subtitle C), the Safe Drinking Water Act, SMCRA,

and the Uranium Mill Tailings Radiation Control

Act (UMTRCA) specify monitoring frequencies.

In addition, the number of monitoring wells is

specified in both the requirements for PCB disposal

sites under TSCA and the interim status requirements under Subtitle C of RCRA.

OTA’s study did not focus on the implementation of Federal regulations (see OTA, forthcoming). A recent General Accounting Office (GAO)

stud y of the RCRA interim status program in four

States indicates a substantial amount of non-compliance with the groundwater monitoring requirements (GAO, 1983). For example, in two of the

four States, 78 percent of the facilities required to

conduct groundwater monitoring were not in compliance with the regulations (e. g., monitoring wells

were lacking and wells were not sited correctly).

Some of the non-compliance was related to the technical complexities of locating and constructing wells

and the costs of well installation, sampling, and

analysis. The States also cited a number of problems regarding enforcement of the RCRA regulations: lack of resources (e. g., staff); lack of technical expertise and guidance; and confusion among

State agencies about jurisdiction over facility inspections.

As indicated in table 30, the interim status requirements (which specify the number of monitoring wells) must be met by hazardous waste land

disposal facilities until a final permit is approved

either by the Environmental Protection Agency

(EPA) or a State with an EPA-approved RCRA

program, EPA estimates that it will take approximately 10 years to review and approve permits for

an estimated 1,350 land disposal facilities nationwide (GAO, 1983).

Certain facilities are exempted from groundwater monitoring requirements. The exemption

or waiver provisions noted below provide varying

degrees of guidance for making exceptions on a siteby-site basis:

•Under the SMCRA regulations for coal mining, monitoring of a water-bearing stratum

may be waived by the regulatory authority if
160 . Protecting the Nation’s Groundwater From Contamination

●

●

it is determined that the stratum is not an aquifer that significantly ensures the hydrologic

balance of the ‘ ‘cumulative impact area.”25

The waiver determination is based on information developed as part of an assessment (referred to as a ‘ ‘probable hydrologic consequences determination”) regarding whether

the mining operation will adversely affect the

hydrologic balance; cause surface or groundwater contamination; and affect groundwater

availability, water quality, or a variety of other

factors. 26

Under the RCRA Subtitle C interim status

program, owners and operators of land disposal facilities can waive groundwater monitoring requirements if they obtain a written

determination, certified by a qualified geologist

or geotechnical engineer, that there is low potential for water migration from the facility via

the uppermost aquifer to water supply wells

or surface water. The waiver document is retained at the facility; it is not submitted to EPA

for review until the facility is called in for final

permit review, which may be as long as 10

years. The evaluation of the potential for migration must be based on an assessment of the

water balance, unsaturated and saturated zone

characteristics, and proximity of the facility to

water supply wells or surface water. 27

RCRA Subtitle C regulations for fully permitted land disposal facilities also contain exemption provisions. Groundwater monitoring

may be waived by the regulatory authority for

facilities if it is determined that there is no potential for migration of liquids to the uppermost aquifer during active, closure, and postclosure periods, Any predictions made about

migration potential must be based on assumptions that maximize the rate of liquid migration. 28 In addition, at landfills, surface impoundments, and waste piles where double

liners and leak detection systems are installed,

exemptions from the detection monitoring proZSThe cumulative impact ~rea is the area within which the proposed

mining operation may interact with all other anticipated mining. (30

CFR 701.5, 48 FR 43985, Sept. 26, 1983).

ZGSee 30 CFR 780,21, 48 FR 43985, Sept. 26, 1983. The regulations specify the types of information that must be submitted to support this,

2740 CFR 265.90(c),

ZS40 CFR 264.90(b)(4).

gram may be granted. A previous OTA study

of the hazardous waste land disposal technologies specified in the RCRA regulations concluded that the lack of groundwater monitoring at double-lined facilities does not protect

groundwater because such systems are not failsafe (OTA, 1983).

Monitoring and Remedial Action

Programs

In addition to the monitoring requirements

described in the previous section, groundwater

monitoring may also be conducted as part of a federally funded remedial action effort-e. g., to characterize a contamination problem and to evaluate

and select among alternative corrective measures.

Table 30 indicates that monitoring is addressed

by programs authorized by AEA, the Comprehensive Environmental Response, Compensation, and

Liability Act (CERCLA), and UMTRCA. Like

the requirements discussed above for permitted or

licensed facilities, explicit groundwater monitoring

requirements are not specified under these programs. Such an approach is consistent with the sitespecific nature of groundwater contamination

problems.

Other Monitoring Activities

A number of Federal agencies are undertaking

additional groundwater monitoring programs with

Photo credit: U.S. Environmental Protection Agency

Hydrogeologic investigations, including soil testing as

shown, provide important input to the evaluation and

selection of corrective actions.
Ch. 6—Federal Efforts To Detect Groundwater Contamination Ž 161

respect to specific sources of contamination. Some

of this work focuses on some of the sources in Categories IV and VI for which no monitoring requirements are established (e.g., fertilizer applications, animal feeding operations, and natural

leaching).

Additional monitoring has been undertaken by

the following Federal agencies:

● The Soil Conservation Service (SCS), in conjunction with the States, private institutions,

and other Federal agencies such as the Agricultural Stabilization and Conservation Service, is involved with several contamination investigations under the Rural Clean Water

Program authorized by Section 208(j) of the

Clean Water Act relating to agricultural operations (table 30). The groundwater data being collected will be used to support the development of Best Management Practices. 29

● EPAs Office of Pesticide Programs has been

involved with several groundwater monitoring studies. For example, the office conducted

monitoring studies where contamination from

pesticide applications was detected. The studies focused on aldicarb and DBCP. In addition, EPA has been evaluating groundwater

quality and the fate and transport of pesticides

in several States (e. g., Wisconsin, Georgia,

and California) in conjunction with the States,

local governments, universities, and other Federal agencies (e. g., USGS). The studies focus

on those pesticides used in each State that,

based on their chemical properties, have the

greatest potential to leach into groundwater

~qcjne s~u~}, ~~ IJ~~CaStcr count ),, PA, is concerned with contamina -

t ion result Ins from w]ur( es such as animal wastes and fertilizer and

pcsticidc applic-ations. Groundwater is being monitored to cstahlish

bac kgrounc] lmels and to aswss the impacts of the Best !tIanagcment

Practices (USDA, 1982) A similar -xuct>’ is being undertaken in eastern

South Dakota (South I]akota State’ Coordinating Committm. 1982).

●

●

(Severn, et al., 1983). EPA and other Federal

agencies have been working together on monitoring related to the formulation and implementation of the National Pesticide Monitoring

Plan (NPMP) under the Federal Insecticide,

Fungicide, and Rodenticide Act.30 A program

directed exclusively at groundwater, however,

has not been implemented .31

The Bureau of Reclamation, in conjunction

with SCS and USGS, is participating in monitoring efforts as part of the Colorado River

Basin Salinity Control Program.32 The sources

of contamination are underlying geologic formations containing salts, which are being

leached due to infiltration of excessive amounts

of irrigation water. The groundwater data collected will be used in the development of irrigation water management strategies.

USGS has programs devoted to three specific

sources of groundwater contamination: 1 ) coal

and oil shale development, 2) radioactive waste

disposal, and 3) toxic waste disposal (see preceding section on Federal Programs) Each involves groundwater monitoring. For example,

as part of the coal and oil shale programs,

USGS is collecting data at thousands of mining areas. Under the Toxic Wastes-Groundwater Contamination Program, field investigations are being conducted on the mobility and

fate of organic substances in groundwater.33

Jo. %cti on 20(b) and (()

s I For add it ion~ d iscusslon ahut the NPM P St>t’ h-at ional Re\earch

Council, 1978.

+ZTh<, c:olor~o R i~,er Basin Sal lnlt f, Con[ ml Act Of 1 !] ~ 4 ( I

>Ub] i(

I.aw 93-320) authorizes construction, operation, and maintenan~ t,

of certain works to cent rol water salinit}, in the (3010rado Ri\er Basin

The program is extensive, cm”cnng se~’en States (California, Arizon,l.

-New \fexico, Colorado, Nc\’ada, Utah, and \$’yoming) di~ided int[)

numerous units. Othcr Federal agencies such as the ASricultur.d

Stabilization and Conscr\ation Ser\ice, EPA, the Bureau of Land

Managcrncnt, and the Fish and Wildlife Service are involted in varloui

aspects of the projcrt, As an example, see DOI, 1983,

JISC<. ~:hasc.. ct al. , 1 ~8~}.

CHAPTER 6 REFERENCES

Absher, S., Office of Solid Waste, U.S. Environmental Baltay, P. Office of Drinking Water, U.S. EnvironProtection Agency, personal communication, August mental Protection Agency, personal communication,

1983. Sept. 13, 1984.
162 ● Protecting the Nation’s Groundwater From Contamination

Chase, E., J. Moore, and D. Rickert, “Water Resources Division in the 1980’s—A Summary of Activities and Programs, USGS Circular 893, 1983.

Cohen, P., Chief Hydrologist, U.S. Geological Survey,

Testimony before the Subcommittee on Natural Resources, Agriculture Research and Environment,

Committee on Science and Technology, U.S. House

of Representatives, May 19, 1983.

Daley, P. S., Director of Environmental Policy, Department of Defense, Testimony before the Subcommittee on Investigations and Oversight, Committee on

Public Works and Transportation, U.S. House of

Representatives, Aug. 10, 1983.

General Accounting Office (GAO), “Solid Waste Disposal Practices, “ July 23, 1981.

General Accounting Office (GAO), “Interim Report on

Inspection, Enforcement, and Permitting Activities

at Hazardous Waste Facilities, GAO/RCED-83-

241, Sept. 21, 1983.

Hester, F. E., Deputy Director, Fish and Wildlife Service, “Hazardous Waste Sites on Service Lands, ”

memorandum, Sept. 22, 1983.

Kimm, V. J., Office o ‘Drinking Water, U.S. Environmental Protection Agency, Testimony before the

Subcommittee on Health and the Environment,

Committee on Energy and Commerce, U.S. House

of Representatives, July 28, 1983.

Langford, R. H., U.S. Geological Survey, Testimony

before the Subcommittee on the Environment and

the Atmosphere, Committee on Science and Technology, U.S. House of Representatives, September

1977.

Lawton, R, H., Deputy Director, Energy and Mineral

Resources, Bureau of Land Management, personal

communication, Nov. 9, 1983.

National Research Council, Pesticide Decision Making

(Washington, DC: National Academy of Sciences,

1978).

Nuclear Regulatory Commission (NRC), “Guidelines

for Groundwater Monitoring at In-Situ Uranium

Solution Mines, Office of Nuclear Regulatory Research, June 1983a.

Nuclear Regulatory Commission (NRC), “Subsurface

Monitoring Program for Sites for Disposal of LowLevel Radioactive Waste, ” NUREG/CR-3164,

April 1983b.

Office of Technology Assessment, Technologies and

Management Strategies for Hazardous Waste ControZ, OTA-M- 196 (\ Washington, DC: U.S. Government Printing Office, March 1983).

Office of Technology Assessment, “Cleanup of Uncontrolled Hazardous Waste Sites Under Superfund,

forthcoming.

Offutt, C., Office of Pesticide Programs, U.S. Environmental Protection Agency, personal communication,

Sept. 30, 1983.

Severn, D. J., C. K. Offutt, S. Z. Cohen, W. L. Burnam, and G. J. Burin, ‘‘Assessment of Groundwater

Contamination by Pesticides, ” Hazard Evaluation

Division, Office of Pesticide Programs, U.S. Environmental Protection Agency, June 7, 1983 (prepared for the FIFRA Scientific Advisory Panel Meeting, June 21-23, 1983, Arlington, VA).

South Dakota State Coordinating Committee, “Oakwood Lakes—Poinsett, Comprehensive Monitoring

and Evaluation Plan, Rural Clean Water Program,

July 1982.

Tewhey, J. D., J. E. Sevee, and R. L. Fortin, “Silresim: A Hazardous Waste Case Study, The Proceedings of the National Conference on Management

of Uncontrolled Hazardous Waste Sites, 1982.

U.S. Department of Agriculture, “Comprehensive

Water Quality Monitoring and Evaluation of Best

Management Practices in the Conestoga Headwaters

Project, Rural Clean Water Program, ” Soil Conservation Service, October 1982.

U.S. Department of the Interior, “Colorado River

Water Quality Improvement Program, Bureau of

Reclamation, Denver, CO, January 1983.

U.S. Environmental Protection Agency, “Draft

Groundwater Protection Strategy, ” December

1983a.

U.S. Environmental Protection Agency, “Supporting

Statement for OMB Clearance Package for National

Inorganic and Radionuclide Survey, ” Technical

Support Division, Office of Drinking Water, Nov.

11, 1983b.

U.S. Environmental Protection Agency, “Inventory of

Open Dumps, ” Office of Solid Waste, May 1983c.

U.S. Environmental Protection Agency, “Surface Impoundment Assessment, National Report, ” draft,

Office of Drinking Water, July 1983d.

U.S. Environmental Protection Agency, “Groundwater

Monitoring Guidance for Owners and Operators of

Interim Status Facilities, ” Office of Solid Waste,

SW-963, March 1983e.

U.S. Environmental Protection Agency, “RCRA Draft

Permit Writer’s Manual-Groundwater Protection , Office of Solid Waste, Apr. 29, 1983f.

U.S. Geological Survey, Statement before the Subcommittee on Toxic Substances and Environmental

Oversight, Committee on Environment and Public

Works, U.S. Senate, July 28, 1982.

U.S. Geological Survey, “Regional Aquifer-System

Analysis Program, ” USGS, W-249-84, 1984.

Westrick, J., Office of Drinking Water, U.S. Environmental Protection Agency, personal communication,

Sept. 7, 1984.
Chapter 7

State Efforts To Detect

Groundwater Contamination
Contents

Page

Chapter Overview.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 165

State

State

State

State

Detection Programs for Sources of Contamination . . . . . . . . . . . . . . . . . . . . . . . . 165

Inventory and Monitoring Activities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 166

Inventory Activities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 166

Monitoring Activities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 167

Formal Procedures for Monitoring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 168

Formal Procedures for Obtaining Groundwater Quality Information . . . . . . . . . . . . . . . . . . 168

Formal Procedures for Using Monitoring Data.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 169

Use, Preferences, and Problems With Techniques for

Hydrogeologic Investigations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 169

Use and Preferences for Techniques . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 169

Problems With Hydrogeologic Investigations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 171

Chapter 7 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 172

31.

32.

33.

OTA State Survey Responses: Number of States Conducting Inventories and

Monitoring Different Categories of Sources of Potential

Ground water Contamination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 167

OTA State Survey Responses: State Use and Preferences for Techniques for

Hydrogeologic Investigations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 170

OTA State Survey Responses: State Problems With Implementing

Hydrogeologic Analyses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 171

FIGURE

Figure’ No, Page

4. OTA State Survey Responses: Number of States With Programs To Detect

Groundwater Contamination From Selected Sources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 166
Chapter 7

State Efforts To Detect

Groundwater Contamination

CHAPTER OVERVIEW

In this chapter, State responses to survey questions about their efforts to detect groundwater contamination are presented. (See the section OTA

State Survey in ch. 4 for guidance in interpreting

survey results. ) The following topics are discussed:

●

●

●

●

sources of groundwater contamination for

which the States have detection programs;

State inventory and monitoring activities;

formal procedures for monitoring; and

State use, preferences, and problems with techniques for hydrogeologic investigations.

Additional information on State strengths, problems, and types of desired Federal assistance related

to detection is found in chapter 4. The techniques

used for detection activities are discussed in chapter 5.

The conclusions drawn in this chapter follow.

The States are working to detect contamination

principally through inventories, source monitoring,

water supply monitoring, and ambient water quality monitoring. Inventory and monitoring efforts

are focused on point sources related to waste disposal and large public water supplies. Not all potential sources of contamination of water supplies

are being monitored.

Most States are working to improve monitoring

and detection but are constrained primarily by institutional or technical factors often related to funding (e. g., technical expertise, manpower, availability of equipment, and the high cost of applying

available technology). The States also experience

technical constraints in conducting hydrogeologic

analyses because of the uncertainties inherent in

groundwater contamination investigations (see ch. 5).

State detection programs are, for the most part,

in the early stages of development. Some States

have made more progress than others. Much of the

activity is handled on an ad hoc case-by-case basis,

relying on the best professional judgment of staff.

This practice is somewhat troublesome for the

States because many have difficulty attracting and

retaining staff with sufficient technical expertise.

All but five States perceive weaknesses with their

detection programs or opportunities for Federal assistance in this area including: funding, technical

assistance, and research and development, as discussed in chapter 4.

STATE DETECTION PROGRAMS FOR SOURCES

OF CONTAMINATION

Many States have detection programs for a va- These programs involve primarily inventory activriety of sources, as shown in figure 4. The highest ities or actual monitoring of groundwater quality

number of States have programs to detect contam- and are discussed in the next section. Other detecination from surface impoundments and landfills tion activities would include inventory control (i. e.,

(both hazardous and sanitary). Generally, more accounting for all material) and/or testing the inState programs are associated with OTA source tegrity of facilities.

Categories I, II, and 111 than with IV, V, and VI.

165
166 Protecting the Nation’s Groundwater From Contamination

Figure 4.—OTA State Survey Responses: Number of States With Programs To Detect Groundwater

Contamination From Selected Sources

— Detectio n

 Correctio n

---- Preventio n

See fig. 2 for footnotes a through g.

SOURCE: Otflce of Technology Assessment.

STATE INVENTORY AND MONITORING ACTIVITIES

State Inventory Activities this information can assist in identifying potential

problem sources:

Inventories are used primarily to locate sites or ● Forty-seven States conduct inventories of pofacilities with the potential to contaminate ground- tential sources of contamination. As shown in

water. A few States have conducted inventories of table 31, the States have inventoried different

substances used in the States that could potentially sources. Most of these efforts have not been

contaminate groundwater (e. g., pesticides, herbi- comprehensive, i.e. , many potential sources

cides, and hazardous substances). Specific contam- of contamination identified by OTA’s analy -

ination incidents are also recorded by some States; sis have not been inventoried.
Ch. 7—State Efforts To Detect Groundwater Contamination . 167

Table 31.—OTA State Survey Responses: Number of

States Conducting Inventories and Monitoring

Different Categories of Sources of Potential

Groundwater Contamination

Source

Source categorya

Inventories monitoring

l— Sources designed to

discharge substances . . . . . . 26 27

ll— Sources designed to store,

treat, and/or dispose of

wastesc 

. . . . . . . . . . . . . . . . . . . 37 42

ll— Sources designed to store

non-wastes d 

... , ., . . . . . . . . . 8 3

Ill— Sources designed to transport

or transmit substances . . . . . 1 0

IV— Sources that discharge

substances as a consequence

of other planned activities . . . 6 10

V— Sources that provide a

conduit g 

. . . . . . . . . . . . . . . . . . 2 0

Vl— Naturally occurring sourcesh . 1 3

Not specified . . . . . . . . . . . . . . . . . . 6 4

None . . . . . . . . . . . . . . . . . . . . . . . . . 3 1

Total number of States . . . . . . . . . . 47 49

‘The states cflci not use consistent terminology In response to questlcms about

their Inventory and monltor!ng actlwtles, responses were classified according to

OTA source categories (see ch 2). Examples of the various types of State

responses included In each category are Ilsted in the respective footnotes,

bunderground Injection wells, surface treatment and disposal systems, waStewater

disposal, sept!c systems, sludge disposal, and drainage wells

clndustrlal waste management areas, hazardous waste SlteS, mIJfllCIPal waste sites,

lagoons, waste treatment systems, open dumps, landfills, waste storage ponds,

and RCRA s~tes

dunderground storage tanks, salt storage and Industrial sites

e Tran s p o f l

a

tlon facllltles

f Urban Clweloprnent, agnculturaf practices, 011 and gas development. related

sources, and mining operations

gWells, springs and active and abandoned wells

hNat ural contamination and saltwater lfltruSIOn

SOURCE Off Ice of Technology Assessment

• The highest number of States inventory Category II sources (designed to store, treat, and/

or dispose of substances). Within this category,

inventories are concentrated on waste-related

facilities. More than one-half the States also

inventory Category I sources (designed to discharge substances). Relatively few States have

conducted inventories of sources in other OTA

categories.

State Monitoring Activities

Having identified potential sources of contamination and, in some cases, substances that are potential contaminants, the States may monitor to

determine whether groundwater is actually contaminated. Monitoring may be directed at various

points of concern: potential sources, water supplies,

and ambient conditions.

Monitoring Potential Sources of Contamination

●

●

●

Forty-nine States monitor sources for potential

contamination. Most of these efforts focus on

Category II waste-related facilities or on other

permitted or licensed activities, including many

Category I sources, as shown in table 31.

Monitoring potential sources of contamination

is generally not comprehensive. All facilities and

activities of a particular source type are not monitored, and some sources are not monitored at all.

For example, four States monitor only selected

facilities within various source categories, and

one State monitors only permitted or licensed facilities. Sources that are not monitored by at least

one State include: direct discharges to groundwater through sinkholes, abandoned hazardous

waste sites that are not currently eligible for corrective action funding under the Comprehensive

Environmental Response, Compensation, and

Liability Act (CERCLA), and many abandoned

solid waste sites.

The sources of priority concern vary among the

States. The highest number of States give priority to Category II sources, particularly hazardous waste sites and substances and landfills.

Monitoring Water Supplies:

●

●

All public drinking water supplies are monitored

for compliance with the Safe Drinking Water

Act. Ten States monitor private wells either on

request or in relation to potential sources of contamination. Few States monitor industrial water

supplies (three) or agricultural supplies (two).

In general, priority is given to public drinking

water supplies. The attention given to monitoring private wells and non-drinking water supplies

varies. One State gives priority to private wells

and one State to supplies other than drinking

water.

Monitoring Ambient Quality

● In general, 38 States monitor ambient groundwater quality or are in the process of developing

such programs. These programs include: relying

on U.S. Geological Survey (USGS) monitoring

of wells; limited monitoring of new wells; monitoring for background quality only in relation to

permit activities; using a statewide monitoring
168 ● Protecting the Nation’s Groundwater From Contamination

network; or monitoring special sites or regions

of concern. Most State ambient quality monitoring to ascertain existing groundwater contamination appears limited.

● Nine States rely on USGS monitoring programs

for information about ambient water quality.

However, USGS recognizes that these are inadequate to detect contamination from organic

substances and trace metals and to provide information on key chemical parameters such as

dissolved oxygen and microbial activity (Cohen,

1983). ‘

● Eight States are in the process of developing

monitoring programs to improve their information on ambient quality. For example, one State

is planning to expand monitoring for pesticides

and radiological substances, particularly in more

densely populated areas.

● Only one State explicitly reported having a statewide groundwater monitoring network. One

State has an ambient water quality network for

the most populous part of the State. Another

monitors selected areas with suspected or known

groundwater quality problems. Four other States

focus on particular sites or regions of concern.

‘ Engerg, 1983, also notes inadequate data collection for pesticides,

radionuclidm, and microbial activity in groundwatm in Nebraska. Similar inadequacies are being found in the seven other States where LTSGS

is conducting appraisals of g-oundwater quality data (Ragone, 1983).

FORMAL PROCEDURES FOR MONITORING

Detection programs involving groundwater monitoring require the systematic collection and analysis of a great deal of technical data, as discussed

in chapter 5. The OTA survey asked the States

about their use of formal policies, procedures, and

guidelines for obtaining groundwater quality information and using Monitoring data. Survey responses further demonstrate the different approaches

that States are taking to detect contamination.

Many States have not formalized their approach

to all activities related to obtaining or using monitoring data; rather, they rely on case-by-case evaluations and their best professional judgments.

Others have formalized policies, procedures, or

guidelines for these activities, but they are not necessarily alike (i. e., different monitoring components

are included by different States, and even when the

States include the same individual components,

they do so in different ways).

Formal Procedures for Obtaining

Groundwater Quality Information

Most States have formalized approaches to collecting and analyzing groundwater quality samples.

At least 17 States rely on Federal guidelines. A few
Ch. 7—State Efforts To Detect Groundwater Contamination ● 169

States prepare their own protocol manuals (e. g.,

seven States for collecting samples and eight States

for analyzing samples).

To determine which parameters to measure at

a particular site, many States also rely on Federal

guidance through lists prepared for various regulatory programs and laws (e. g., the National Interim Primary Drinking Water Regulations, coal

mining regulations, and the list of Priority Pollutants). Reliance on Federal lists is a problem for one

State, which commented that routine sampling as

required in the Safe Drinking Water Act needed

to be changed to cover substances more commonly

used in the State.

Formal Procedures for Using

Monitoring Data

Forty-three States make routine comparisons of

monitoring data with quality standards. Of the 23

States that described their efforts, 13 make routine

comparisons only for drinking water; 6 conduct

routine comparisons in relation to specific facilities

or permit programs for activities with the potential to contaminate groundwater; 2 make routine

comparisons for all monitoring wells; and 2 make

comparisons only during special studies (e. g., contamination investigations or public health studies).

Twenty-two States have formal policies on the

confidentiality of the groundwater information that

they collect. State policies on public accessibility

to groundwater information vary. For example, in

some States information is confidential only if litigation or a trade secret is involved. Information may

be confidential in some States if requested by landowners. In one State, information is confidential

only if pollution is confined to the property of the

polluter. One State noted that essentially nothing

is confidential.

All but one State detect groundwater contamination by responding to complaints of suspected contamination. About one-half of the States have formal policies, guidelines, or procedures for this

purpose. Types of formal policies vary, ranging

from record-keeping activities to policies that are

incorporated in regulatory programs for particular sources. Four States have established, or are in

the process of developing, special groundwater contamination response programs.

A few States noted problems in responding to

complaints about possible contamination. The

problems primarily reflect limited resources for the

effort. In one State only a fraction of the complaint

responses were timely. Another State noted that it

sometimes charges for sample analyses.

USE, PREFERENCES, AND PROBLEMS

WITH TECHNIQUES FOR HYDROGEOLOGIC

INVESTIGATIONS

Use and Preferences for Techniques

The use and preferences of the States for various

techniques to collect hydrogeologic data are shown

in table 32. Most States use a variety of techniques

to conduct hydrogeologic analyses. Although some

States use a technique routinely, others may use

it only in special circumstances or not at all. Certain techniques are notable for their routine use by

most states (e.g. , unpublished and published studies, mapping, and excavations and drilling). Other

techniques stand out because they are not used

routinely by many States (e. g., remote sensing with

satellites, hydraulic testing tracer tests, contaminant transport modeling, and ground-penetrating

radar), but some States apply these techniques in

special circumstances.

Only excavations and drilling test wells are preferred by more than one-half the States. Reasons

given for preferring particular techniques include:

cost, time, availability of equipment, and technical capability (relates to ease of use, staff expertise

required, reliability and accuracy, value of results,

38-799 n - 84 - 8 : QI, 3
170 . Protecting the Nation’s Groundwater From Contamination

Table 32.—OTA State Survey Responses: State Use and Preferences for Techniques

for Hydrogeologic Investigations

Number of States:

Using in Having

Using special preference

Categories of techniques routinely circumstances for use

Unpublished and published information:

(Existing studies). . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Mapping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Remote sensing:

Aerial photography . . . . . . . . . . . . . . . . . . . . . . . . . . .

Satellite imagery . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Excavations and drilling:

(Test wells) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

(Stratigraphy) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Geologic sampling . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Hydrometeorologic measurements:

(Climate,l . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Surface hydrology:

Hydraulic measurements (watershed analysis) . . . .

Surface water sampling . . . . . . . . . . . . . . . . . . . . . . .

Subsurface hydrology:

Potential measurements. . . . . . . . . . . . . . . . . . . . . . .

Hydraulic testing:

(Trace- tests) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

(Aquifer tests) . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Laboratory testing . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Water quality sampling. . . . . . . . . . . . . . . . . . . . . . . .

Hydrogeologic systems analysis:

Modeling

(Groundwater flow modeling). . . . . . . . . . . . . . . . .

(Contaminant transport modeling ) . . . . . . .. . . . .

Geostatistics . . . . . . :........ .

Surface geophysics:

Electrical resistivity and

electromagnetic conductivity

(Surface potential) . . . . . . . . . .

Ground-penetrating radar

(Surface-penetrating radar) . . .

Shallow geothermic method

(Temperature). . . . . . . . . . . . . .

Subsurface (borehole) geophysics

Hydrogeochemistry-(sniffers)d . . .

-.

. . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . .

44

42

21

2

40

39

N Q

b

28

28

NQ

NQ

3

25

NQ

NQ

3

7

28

26

16

19

NQ

NQ

24

20

9

0

o

0

NQ

NQ

4

19

NQ

NQ

11 34 5

3 35 3

NQ NQ NQ

10 32 7

3 24 1

7 18 0

21 24 13

7 23 1

aThe techniques listed are the Same as those presented in ch. 5. The terminology used in the OTA State Suwey iS shown in

parentheses, indifferent

%he OTAStatisurvey did not specifically question States about their use and preference for this technique.

cThe States Were questioned about subsurface geophysics in general Informationon specific techniques was not requested.

dsniffers were ttle only hydrog~tlemistry technique included in the survey. More conventional measurements (e.9., PH) are probably

used by more States with greater frequency,

SOURCE: Of fic~ of Technology Assessment.
Ch. 7—State Efforts To Detect Groundwater Contamination ● 171

Photo credit: ~atiorral Water Well Association

Although many techniques are available for conducting

hydrogeologic investigations, some techniques are not

used routinely such as ground-penetrating radar.

and applicability to hydrogeologic conditions).

These factors influence both the choice of techniques for hydrogeologic investigations that a State

conducts and the decision on what the State can

reasonably require under its regulatory authority.

Problems With Hydrogeologic

Investigations

Forty-nine States described problems in conducting hydrogeologic analyses. Table 33 classifies these

problems with analyses as technical, institutional,

or legal. General findings from this table are below:

● The States experience a variety of problems

in conducting hydrogeologic analyses, and different States have different problems.

● The most common problems are institutional.

Funding for analyses is a problem for the highest number of States. Other frequently cited

institutional problems, often related to fundTable 33.—OTA State Survey Responses: State

Problems With ImpIementing ydrogeologic H

Analyses

Number of Statesa/Types of problems

Technical problems:

13 Intensive data requirements for particular techniques

and lack of data

16 Difficulties in interpreting data and with accuracy of

techniques (e.g., for dealing with multiple sources

and/or complex hydrogeologic environments)

4 Lengthy time required to conduct analyses

1 Timing constraints (e.g., seasonal limitations with

some equipment)

2 High expense and questionable cost effectiveness

4 Limited technology (e.g., most organic contaminant

analyses require collection of water quality

samples; monitoring techniques are inadequate for

karst environments; and contaminant transport

models are not well developed)

Institutional problems:

19 Lack of manpower

36 Lack of funds

27 Inadequate technical expertise (e.g., difficulty

attracting and/or retaining qualified professionals)

13 Unavailability of equipment

2 Over-reliance on consultants

1 Inadequate laboratory capabilities

2 Difficulties in keeping up with technical

advancements

2 Lack of interagency coordination

1 Lack of public confidence in the State

Legal problems:

2 Water rights conflicts

10 Difficulties in obtaining site access (e.g., permission

to drill off site)

1 Confidentiality of information (e.g., proprietary

pumpage records)

1 Difficulties in recovering costs of investigations from

polluters

aForty.nine States responded to this question

SOURCE: Office of Technology Assessment

●

●

ing, include inadequate technical expertise,

lack of manpower, and unavailability of

equipment.

The most common technical problems include:

difficulties in interpretation of data, inaccuracy

of techniques, and intensive data requirements

for particular techniques. Four States noted

a lack of technology to investigate particular

contaminants or hydrogeologic environments,

and seven others noted a need for advancements in detection techniques.

Legal problems with the use of hydrogeologic

techniques were reported by relatively few

States. The most common is obtaining access

to areas to drill and investigate possible contamination.
172 ● Protecting the Nation's Groundwater From Contamination

CHAPTER 7 REFERENCES

Cohen, P., Chief Hydrologist, U.S. Geological Survey, Quality in Nebraska, ” U.S. Department of the InStatement before the Subcommittee on Natural Re- terior, U.S. Geological Survey Open-File Report 83-

sources, Agriculture Research, and Environment, 128, 1983.

Committee on Science and Technology, U.S. House Ragone, S., U.S. Geological Survey, personal commuof Representatives, May 19, 1983. nication, Mar. 25, 1983.

Engerg, R. A., “Appraisal of Data for Ground Water
Correction
Chapter 8

The Correction of Groundwater

Contamination: Technologies and

Other Alternatives
Contents

Page

Chapter Overview.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 177

Selecting a Corrective Action Strategy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 177

Technical and Non-Technical Conditions Determining the Applicability of

Corrective Action Alternatives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 179

Performance of Corrective Action Alternatives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 183

Stage of Development of Corrective Action Alternatives . . . . . . . . . . . . . . . . . . . . . . . . 192

Chapter 8 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 193

TABLES

Table No. Page

34. Corrective Action Alternatives: Techniques and Descriptions . . . . . . . . . . . . . . . . . . . . . 178

35. Corrective Action Techniques: Objectives, Performance, and Status . . . . . . . . . . . . . . . 185
Chapter 8

The Correction of Groundwater

Contamination: Technologies and

Other Alternatives

CHAPTER OVERVIEW

Correction is broadly defined in this study to include reducing concentrations of, eliminating, or

otherwise controlling contaminants in groundwater.

This chapter describes the principal technical and

management options available for corrective action

and analyzes them in terms of their applicability

under different conditions, performance, and stage

of development. Technical options are categorized

under containment, withdrawal, treatment, and insitu rehabilitation; management options, which

may have technical components, are a fifth category. These categories generally reflect differences

among alternatives in terms of how and where

substances are acted upon.

Although there is a wide variety of alternatives

for correcting groundwater contamination, their effectiveness is uncertain. Experience with them is

limited, their applicability can be determined only

in relation to given site conditions, and their performance over the long term is an unknown. Some

technologies are new, but many are commercially

available, having been developed for surface water,

industrial, and other purposes.

SELECTING A CORRECTIVE ACTION STRATEGY

The principal options available for corrective action are shown in table 34. Although there is a wide

variety of options, no one alternative is capable of

responding to all conditions likely to be found at

a groundwater contamination site. Rather, options

tend to address specific hydrogeologic components,

objectives, or steps (refer to table 24) in a corrective action process. For example, options in the

treatment category assume that contaminated water

is already in the treatment system and do not address how it will be removed from the subsurface

(e.g., with withdrawal methods). Thus, in practice,

alternatives are combined in a corrective action

strategy to take advantage of their complementarities.

Selecting a combination of alternatives involves

making tradeoffs—among time, costs, performance, and other factors—and not all tradeoffs are

quantifiable. As yet, there is no standard approach

to formulating corrective action strategies, in large

part because groundwater contamination is site-specific and experience is limited. Experts contacted

for this study stressed the need for a more scientific and less ad hoc approach in applying and tailoring combinations of techniques to sites. Such a

methodology would systematically consider site conditions, resource constraints, and performance objectives in evaluating and selecting among alternatives.

Experience appears to show that the selection of

a corrective action strategy is not primarily based

on lowest costs. Rather, selection appears to be

based on how quickly methods can be implemented, how quickly they are expected to achieve

desired results, and the uncertainty associated with

their performance. Considerations in selecting techniques, which have been identified on the basis of

case histories, include: the potential for a public

177
—

178 ● Protecting the Nation’s Groundwater From Contamination

Table 34.—Corrective Action Alternatives: Techniques and Descriptionsa
Ch. 8—The Correction of Groundwater Contamination: Technologies and Other Alternatives • 179

Table 34.—Corrective Action Alternatives: Techniques and Descriptionsa—continued

10.

1.

12.

13.

or adhere on the surface of another substance (e,g.,

granular activated carbon and synthetic resins) with

which they come into contact.

Electrodialysis: Separates and removes positive or

negative ions under the action of an electrical field.

Chemical transformation: Involves oxidation-reduction

reactions for the chemical conversion of contaminants

to less toxic substances (e.g., by ozone treatment,

hydrogen peroxide treatment, ultraviolet photolysis,

and chlorination).

Biological transformation: Involves the transformation

and removal by micro-organisms of dissolved and colloidal biodegradable contaminants; includes both aerobic and anaerobic processes.

Incineration: Involves the high-temperature transformation of contaminants into constituent components;

many types of thermal destruction systems are included.

lV. In-situ rehabilitation: In-situ rehabilitation techniques are

directed at immobilizing or otherwise detoxifying contaminants in place.

1. Biological degradation: Involves either stimulating the

growth of native microflora or injecting specific organisms to consume or otherwise alter contaminants.

2. Chemical degradation: Involves the injection of

specific chemicals that react with or otherwise alter

contaminants.

3. Water tab/e adjustment: Involves either the isolation

of the contaminated zone (and creation of a detoxifying unsaturated environment) by lowering the water

table or the artificial inducement of increased flushing action by raising the water table.

v.

4. Rehabilitation via natural processes: Involves the natural degradation, dispersion, or detoxification of contaminated groundwater; is evaluated by analytical

and/or empirical methods.

Management option: Management options are usually

applied either to prevent further contaminant ion or to protect potential exposure points from contaminated

groundwater. These methods thus focus on sources and

exposure points rather than on the contaminants per se.

The methods also tend to be institutionally-based rather

than technology-based.

1.

2.

3.

4.

5.

6.

7.

Limit/terminate aquifer use: Limits access or exposure

of receptors to contaminated groundwater.

Develop alternative water supply: Involves the substitution of contaminated groundwater with alternative

supplies (e.g., surface water diversions and/or storage,

desalination, and new wells).

Purchase alternative water supply: Includes bottled

water and water imports.

Source removale

: Involves the physical removal of the

source of contamination and includes measures to

eliminate, remove, or otherwise terminate source activities; could also include modification of a source’s

features (e.g., operations, location, or product) to reduce, eliminate, or otherwise prevent contamination.

Monitoring: Involves an active evaluation program with

a “wait and see” orientation.

Health advisories: Involves the issuance of notifications about groundwater contamination to potential

receptors.

Accept increased risk: Involves the decision to accept

increased risk; is usually a “no action” alternative.

aBa~ed on Woodward.Clyde Consultants, Inc, lg83. See this reference for a detailed bibliography on Spec( flc correct ive actlofl alternatives

bean be ~o n s ldere d a form of chemical lmmoblllzatlon If Injected directly Into the plume of contamination

C p ~y5, c a l barrler5 located above the ~ate~ table WIII not affect the horizontal mlgratlon of contaminants In the saturated zone

d Mo st often “Se d ,n the context of either ,~ource removal” or the prevention of recharge to the groundwater System. rather than as a COfltalflmf3flt Optl Ofl per S’

‘Modlf, cat, on of a Source , 5 features ,5 often an Important element of corrective action In the context of preventing future ground water contamination (1 e , reducing

the need for future corrective action)

SOURCE Off Ice of Technology Assessment

health or environmental hazard, the potential for

any hazard to become more serious over time, the

potential for loss of public confidence, the potential for liability, and fear of the unknown (Woodward-Clyde Consultants, 1983).

Technical and Non-Technical

Conditions Determining the

Applicability of Corrective

Action Alternatives

The applicability and selection of alternatives for

a groundwater contamination problem depend on

site conditions. Conditions are technical (e. g., geologic setting, aquifer type, saturation, and type and

concentration of substances) and non-technical

(e.g., cost, time, safety, and institutional factors).

They are described in detail in appendixes F. 1 and

F.2, respectively.

There are site conditions that limit all technology-based corrective action strategies, assuming a

stringent criterion for contaminant reduction, elimination, or control. Among these conditions are:

1) the presence of multiple bodies of contamination at a site and/or complex mixtures of substances;

2) heterogeneous, highly complex aquifers; 3)

depths of contamination beyond approximately 20

meters; and 4) the presence of substances that partition (i. e., separate) out of water and are non-biodegradable. The degree to which these constraints

effectively preclude application of technology de-
180 ● Protecting the Nation’s Groundwater From Contamination

pends to a large extent on whether substances can

be withdrawn and treated.

Often withdrawal and treatment are not possible. For example, the application of some withdrawal methods (e. g., pumping) is limited in unconsolidated, fine-g-rained materials of low permeability

and may be impractical (in terms of time and costs)

if high water volume handling requirements are involved. Individual treatment techniques address

specific types of substances, and no single technique

is applicable to the mix of substances often found

in groundwater. Further, sudden temporal changes

in the types and/or concentrations of substances

passing through a treatment system can lessen treatment effectiveness. Thus, several treatment techniques would generally be required to treat contaminated groundwater, but even then there is no

guarantee that all substances will be reduced to

desired levels.

Other conditions that determine and often restrict the applicability of corrective actions to a given

site

●

●

●

include:

hydrogeology, e.g., methods requiring construction (many containment methods and excavation) are often technically impractical in

hard rock; material barriers depend on the

presence of a horizontal stratum of low permeability and sufficient thickness for anchoring; and highly fractured sedimentary or crystalline rock precludes the use of most techniques

except pumping, treatment (if withdrawal can

be accomplished), and grouting;

types and concentrations of contaminants,

e.g., special handling and disposal may be required with options involving construction or

withdrawal in the presence of certain substances; high concentrations severely reduce

the efficiency of withdrawal; mixtures of substances reduce the efficiency of treatment; and

multiphase flow (as when substances are immiscible in and denser than water) poses special

design and implementation problems for most

methods;

depth, e.g., methods involving construction

equipment are generally limited to depths of

approximately 20 meters;

●

●

●

environmental and health effects, e.g., health

effects are associated with containment and

management options that allow the continued

presence and potential for continued migration of substances; environmental effects potentially include alterations to existing groundwater flow patterns if construction or pumping

is involved and the introduction of biological

or chemical agents—and the continued presence of altered substances—with in-situ rehabilitation; and some treatment options can

have air pollution side-effects (air stripping);

cost, e.g., depending on site conditions, costs

can be tens of millions of dollars or more; containment tends to be capital-intensive during

construction and installation with relatively

small long-term operation and maintenance

costs, while withdrawal is less capital-intensive

overall but has significant long-term operation

and maintenance costs; and cost considerations

have effectively precluded corrective action in

areas larger than about O. 1 km2 and for volumes exceeding about 1,000 m3

; and

performance objectives in terms of the continued presence of substances—e. g., excavation eliminates substances from a site relatively

quickly but depends on the availability of

an alternative site for disposal of excavated materials; pumping may remove high concentrations of substances in the near term, but decades of pumping may be required before a

significant additional reduction is achieved;

and treatment may also be required over the

long term and removal efficiencies are highly

variable.

Appendix F.3 summarizes information about

conditions determining the applicability of corrective action alternatives in relation to the OTA

source categories discussed in chapter 2 (refer to

table 5). Essentially, no technically based corrective action can stop a source from causing contamination: 1) if the source is deep, such as many

sources in Category I (i. e., sources designed to discharge substances) and Category V (i. e., sources

that provide a conduit); or 2) the source releases

substances over a wide area or if large volumes of

water are involved, as in Category IV (i. e., sources

that discharge substances as a consequence of other
Ch. 8—The Correction of Groundwater Contamination: Technologies and Other Alternatives Ž 181

-

. ,

,

.

,

,

Photo cradt: Geraghb’ & Miller, 198.3

Movement of contaminated groundwater can sometimes be controlled by pumping (i.e., hydrodynamic control) as shown

above. Groundwater that is withdrawn must subsequently be treated and/or disposed of in some way; below, discharge

lines carry recovered water away from the site.
182 ● Protecting the Nation’s Groundwater From Contamination

Credit: Geraghty & Miller, 198.3

Containment options that use material barriers depend on the presence of a horizontal stratum of low permeability and

sufficient thickness for anchoring as shown above; some type of pumping scheme (e.g., wells or drains) may also be

needed to prevent the overflow of contaminated water from inside the barrier. Backfill is being pushed

into an almost completed slurry wall in the photograph below.

Photo credit: National Water Well Association
Ch. 8—The Correction of Groundwater Contamination: Technologies and Other Alternatives . 183

Photo credit: US. Environrnenta/ Protection Agency

Airstripping towers can be used to remove contaminants from groundwater; however, precautions

must be taken to minimize any associated air pollution problems.

activities including pesticide and fertilizer applications).

Performance of Corrective Action

Alternatives

Corrective actions have been taken to improve

groundwater quality, but how well they perform

remains uncertain over both the short and the long

term. Inability to characterize performance of corrective measures arises because of the following five

interrelated factors.

1 ) Performance is relative. Evaluation of performance requires the establishment of a benchmark or a target level for comparison. For example, when the desired reduction in contaminant

concentrations is minor, many corrective action

alternatives may qualify as ‘‘effective, but as the

levels of desired or required cleanup increase, many

alternatives may no longer qualify. Performance

is also measured not only against existing conditions but in relation to future conditions—i.e., the

suitability of improved quality to satisfy likely future

uses.

2) Performance must be assessed in relation to

the specific conditions at a given site (see the preceding section of this chapter). The site-specificity

of groundwater contamination problems and, in

turn, of the applicability of corrective action alternatives precludes a meaningful generalized assessment of technology performance.
184 Ž protecting the Nation’s Groundwater From Contamination

3) Even when site information is available, there

is always some degree of uncertainty about the subsurface environment —e.g., which substances are

present, at what levels, and where (see ch. 5)—

that can limit the effectiveness of alternatives in

unforeseen ways. The principal uncertainty factors

that influence performance are summarized in table

35 and relate to materials compatibility, the heterogeneity of the aquifer, and the types of substances present. Others are related to the qualifications of personnel and the quality of construction,

handling, and operation.

4) There is virtually no long-term experience

upon which to base the assessment of corrective

actions. For example, although there have been federally funded cleanup activities under the Comprehensive Environmental Response, Compensation,

and Liability Act (CERCLA) and other Federal

statutes, none has involved groundwater (see ch.

9). As a consequence, a then-ough performance evaluation of individual alternatives under different site

conditions will not be available in the near term.

Although many case histories are reported in the

literature, they often do not contain enough detail

for an evaluation of technology performance. In addition, access to information appears limited because it is often proprietary or involved in litigation.

5) The projected performance of technology and

the degree of uncertainty about its performance

depend on the time available to meet cleanup objectives or standards desired (e. g., as specified in

permits, presented in a notice of regulatory compliance, and in response to public pressures) and

on available funds. For example, in addition to

specifying the levels to which the concentrations of

substances must be reduced, a time frame may also

be specified.1 Time constraints may preclude many

corrective act ion alternatives from consideration,

perhaps resulting in a choice among more costly

options; or desired cleanup standards may be neither technically nor economically feasible in the

time specified.2

1 In a surx’cy of rcmedial action projects undertaken for EPA (SCS

Engineer-s, 1981 ), legal action to identify ‘ ‘responsible” parties for

correct i~’c action alone varied from 4 to 9 }’ears.

‘For example, if cleanup stan+~ards must be achieved in, say, 5 years,

then a time- and capital- inten: i~e method of containment may have

to be chosen (e. g., a slurry wall requiring replacement once etery 50

Although an accurate performance assessment

is not presently possible, it is possible to reduce

the uncertainties associated with performance

and/or to improve the likelihood that an alternative will perform well. Examples are described

below:

●

●

●

●

The evaluation, selection, design, and implementation of corrective action alternatives are

based on information obtained from hydrogeologic investigations. Thus, improving the

reliability of hydrogeologic information (see

ch. 5) will improve corrective action decisionmaking.

Realistic expectations in terms of objectives,

time, and costs are important in ensuring that

failure is not inevitable.

Monitoring can gauge long-term effectiveness

and enable modification of the corrective actions chosen if necessary. But measuring performance is indirect and varies among the

alternatives. Possible indicators of performance are presented in table 35.

Quality control and quality assurance procedures—e.g., regarding the use of construction

equipment on-site and the handling and placement of physical barriers—can also minimize

the likelihood of poor performance.

Importantly, different types of uncertainties are

associated with different alternatives, and the performance of some may be more certain (though not

necessarily more desirable) than others, depending

on site conditions. Management options are most

often selected because their performance is the most

certain. For example, terminating aquifer use depends neither on subsurface hydrogeology nor on

the nature and behavior of substances; over the long

term, however, there may be a risk of public exposure to substances remaining in the subsurface.

years), precluding methods that have long-term operational requirements but smaller capital costs (c. g., hydrodynamic control). A net

present value criterion would select hydrodynamic control in the abscncc of a near-term time constraint. However, a pumping system

ma}’ achie~e a 90-percent reduction in contain inant concentration levels

in 5 years, but an additional 50 years may be required to reach a ~oal

of 95-percent reduction.
o

I

I

to

?

w

Table 35.—Corrective Action Techniques: Objectives, Performance, and Status

Principal components

of uncertainty Measuring Development status

Technique Objective affecting performance performance Summary a Remarks

Containment

1. Slurry wall To halt the horizontal migration

of contaminants

from a contamination plume;

often used in

conjunction

with surface

seal, run-on, and

runoff controls.

2. Sheet pile

3. Grouting

Same as slurry

wall.

To encapsulate

contaminants

(via bottom and

lateral grouting).

● Long-term materials compatibility, particularly with certain

organic solvents such as

aromatics and halogenated

species.

● Wall consistency and integration with the confining bed.

● Longevity of walI integrity.

Ž Quality of design and

installation.

● Occurrence of premature piIe

failure, especially in the

presence of highly concentrated corrosive contaminants.

● Contact between the grout

materials and all fracture and

pore spaces.

● Compatibility of formation

fluids and wastes with grout

materials.

Performance of a slurry wall is

is determined by various

methods. Monitoring well data

outside of the wall can indicate the degree of leakage.

Hydraulic head differences

determine leakage potential;

actual leakage can be calculated. Head measurements

in underlying aquifers determine

potential for vertical leakage.

Permeability measurements

of confining bed also determine leakage potential.

Same as slurry wall except that

measurements are taken at

specific places where

leakage is expected to occur,

e.g., at pile joints and

where piles are integrated

with the confining bed.

Encapsulation processes cannot

be easily monitored or controlled (e.g., a barrier wall can

be more easily inspected

during construction than

injected grout; and grout

injection is not as easily controlled as trenching). interpretation of monitoring well data

for downgradient contaminants is the principal measure

of performance.

2

2

2

Technology for conventional,

trenched slurry walls is well

established as a construction

dewatering practice; however,

allowable leakage for construction applications is less

critical than for contamination

applications. In general, longterm (30 years) performance

evaluations are not available

because the operation requirements of dewatering are

usually short term (less than

1 year). Historical records of

long-term performance under

exposure to varying contaminant types is also unavailable. Advanced techniques,

such as the vibrating beam

emplacement method, have a

limited history of application

to contamination problems

and should be considered

unproven.

This technique is conventionally

used for construction dewatering. Its long-term viability in

corrosive environments (e.g.,

acid wastes) is unproven.

Also, the effectiveness with

which the method can limit

contaminant migration is

questionable for stringent

performance criteria (e.g., if

low or no leakage is desired.)

Grouting is conventionally used

in mine dewatering and dam

construction. Design requirements in historical uses are

generally to limit water flow,

not to minimize or eliminate

flow or to encapsulate

contaminants.
Table 35.—Corrective Action Techniques: Objectives, Performance, and Status-continued

Principal components

of uncertainty Measuring Development status

Technique Objective affecting performance performance Summary a Remarks

4. Geomembrane Same as slurry

wall.

5. Clay cutoff To halt the horizontal migration

of contaminants

(in the unsaturated zone).

6. Liner To limit the

vertical migration of contaminants;

commonly used

as a facility

design

component.

7. Natural To contain or

containment otherwise limit

the migration of

contaminants

via retardation

in aqueous

media, in geologic formations, or by

hydrogeologic

conditions.

8. Surface sealing To limit infiltration

into the contaminated area;

commonly used

in conjunction

with runoff diversion ditches

and material barriers (e.g., slurry

wall and grouting) and with

Compatibility of synthetic - same as slurry wall. “

membranes with organic

solvents.

Installation of a vertical

liner with grout backfill without damage.

Integration ot the liner with

the confining bed.

Compatibility of materials and

quality of installation.

Occurrence of punctures due

either to improper installation

or to settling of underlying

materials.

Impacts of organic solvents

on synthetic liners or clays—

e.g., holes or reduced effective permeability.

Quality of materials selection

and installation.

Representativeness of characterization of hydrogeology

and contaminant retardation.

● Accuracy and completeness

of data, especially concerning contaminant retardation.

● Heterogeneity of subsurface

conditions.

● Quality of management,

inspection, and repair.

Monitoring in the vicinity of

the cutoff can be accomplished with suction lysimeters, core samples, and

other techniques applicable

to the unsaturated zone.

Performance of liners can be

monitored by underdrain

collection systems or conventional monitoring well

techniques.

Detection of contaminants in

monitoring wells can verify

predicted migration rates.

Visual inspection can locate

holes or cracks. Increased

Ieachate production indicates

leakage. Also, increased

pumpage requirements in

head management system

may indicate leakage.

3

2

1

5,6

1

Contamination applications are

A

are in the R&D phase

although the technology is

commercially available. Field

tests are only now being conducted; long-term performance data are not available.

clay cutoff is a standard

construction technique but it

has limited utility in groundwater contamination applications because horizontal migration in the unsaturated

zone is most often negligible.

Liner technology is well established and has been applied

extensively to groundwater contamination problems.

However, long-term performance data for both synthetic

liners and compacted clays

are limited. The use of underliners is limited mainly to

hazardous-waste facility

design.

Techniques are available to

predict the general direction

and rate of movement of

natural flow systems. But

techniques used to predict contaminant migration

rates and concentration levels

(e.g., solute transport models)

are not well established and

subject to great uncertainty,

particularly in the absence

of supporting data.

Conventional construction techniques are used to emplace

surface seals. Effective infiltration control requires

constant maintenance (e.g.,

due to the formation of

stress cracks from settling

or drying after dewatering).

●
Table 35.—Corrective Action Techniques: Objectives, Performance, and Status— continued

Principal components

of uncertainty Measuring Development status

Technique Objective affecting performance performance Summary a Remarks

source isolation

(e.g., to eliminate Ieachate

production).

9. Diversion To divert surface

ditches runoff away

from the contaminated area.

10. Hydrodynamic To isolate concontrol taminants via

countering hydraulic

gradients.

Withdrawal

1. Pumping To limit the lateral

migration of

contaminants

while gradually

removing them

from the aquifer

matrix and formation fluids.

(Source removal

and/or isolation

is also required

to achieve ultimate reduction

in contaminant

concentrations.)

● No major concerns.

● Changes in local flow patterns

due to modifications in existing pumping schemes or to

installation of new pumping

wells.

Ž Downward flow which could

allow contaminant migration

into uncontrolled aquifers.

Visual inspection is used to

measure performance—e.g.,

during precipitation events.

Water levels can be monitored

in surrounding wells to observe

gradients.

1 This technique is a conventional construction method

used for run-on/runoff control.

It is often used in conjunction with surface seals.

1,4 Techniques are not considered

conventional or “on-the-shelf.”

Management of plumes and

contaminant isolation in complex hydrogeologic settings

require extensive engineering

and testing. Long-term effectiveness is a function of constant fine-tuning to changes

● The necessary length of time Contaminant concentration levels 1

for operations. can be measured in produced

● Downward leakage of con- water to determine removal

taminants due to fracture rates; and effects of pumping

systems, jointing, and aban- can be verified by monitoring

doned wells. water levels in surrounding

wells. Underlying aquifers

must be monitored to detect

downward migration. Concentration levels after pumping

is terminated must be monitored to determine increases

in concentrations due to

resorption. Geochemical

interactions between contaminants and the aquifer

matrix affect the partitioning

of the contaminant between

solid and water phases; the

potential effectiveness and

length of operations are

dependent on these

interact ions.

in head gradients. In dynamic

flow systems (e.g., in systems

modified by other pumping

uses), pumping rates or patterns will require modification in real time.

Pumping techniques (e.g., wells)

are used conventionally for

water supply development and

more recently for plume

management. Techniques are

reliable and performance can

be verified. Numerous applications to groundwater contamination are in place, and

performance data are available.
Table 35.—Corrective Action Techniques: Objectives, Performance, and Status—continued

Principal components

of” uncertainty Measuring Development status

Technique Objective affecting performance performance Summary a Remarks

2. Gravity Same as pumping. -

same as pumping. Same as pumping. 1

drainage

3. Withdrawal To enhance conenhancement taminant removal efficiencies via the

the injection of

chemicals,

steam, or other

additives.

4. Gas venting To remove volatile

contaminants

from the subsurface.

5. Excavation To remove

contaminated

water and/or

soil materials.

Ž Lack of proven effectiveness Same as pumping.

of technology.

● Introduction of additional

contaminants to the aquifer

(e.g., chemical reagents and

their byproducts).

● Introduction of volatiles to

the atmosphere (e.g., via the

use of steaming in surficial

applications).

. Presence of inorganic substances (i.e., use is limited to

organic constituents).

2,3,4b

● Lack of proven effectiveness Measurements can be taken 1

in complex media. using gas collection probes.

Ž Increased contaminant migration (e.g., via breaking of

drums or additional infiltration during precipitation).

● Availability of secure disposal

areas for excavated

contaminants.

● Extent of contamination and

resulting costs.

Contaminant concentration 2

levels can be measured in

surrounding soil and aquifer

materials and in surrounding

waters to verify total removal.

Measurements are most

accurate if contaminants are

highly concentrated and

limited in depth and volume.

A type of fluid recovery technology, this method is used

extensively in dewatering

activities and for groundwater

contamination. It is a reliable,

simple technique which is

applicable in many surficial,

unconsolidated formations.

Performance data are

available.

This technique is not conventionally applied to groundwater contamination problems. Steam or heat injection,

although used in confined

formations in oil field applications, have not been extensively tested in surficial contamination problems where

concentrations of organics are

much lower and objectives for

removal are more stringent

(50% recovery of oil in place

is often considered reasonable). Surfactant injection is

still considered an advanced

technique in enhanced oil

recovery operations, and

injectants are often considered hazardous.

Gas venting is conventionally

used in landfill design and

operation. Vapor extraction

in the unsaturated zone

appears capable of removing

the soluble fraction of

volatile compounds from the

saturated zone.

Direct excavation is a conventional technology. However,

associated health and safety

measures are continually

under development and are

likely to increase costs

substantial y.
Table 35.—Corrective Action Techniques: Objectives, Performance, and Status—continued

Principal components

of uncertainty Measuring Development status

Technique Objective affecting performance performance Summary a Remarks

Treatment In general, to

transform

(thereby removing) contaminants via physical, chemical,

or biological

means.

In-situ rehabilitation

1. Biological To degrade

degradation contaminants

via the injection

of microorganisms into

the subsurface

or by stimulating the growth

of in-situ

bacteria.

2. Chemical To degrade or

degradation immobilize

contaminants

via the injection

of chemicals

into the subsurface.

● Uncertainty Increases it contaminants are neither highly

concentrated nor limited in

depth or volume.

● Occurrence of shock loadings.

Nature, mix, and concentration of contaminants; uncertainty increases if contaminants are not highly

concentrated.

Equipment design and

operation (e.g., membrane

maintenance for filtration,

ultrafiltration, and electrodialysis; and proper controls for

providing reagents for adsorption and chemical transformation).

Subsurface hydrogeology to

the extent that contaminated

groundwater is to be withdrawn from the aquifer.

● Contact between the reagents

and the entire contamination

mass, particularly in heterogeneous aquifers.

● Predicting the behavior of

micro-organisms.

● Tailoring micro-organisms to

contaminants.

Performance is highly

uncertain.

Contact between the reagents

and the entire contamination

mass, particularly in heterogeneous aquifers.

Performance is highly

uncertain.

In general, influent and effluent 1

C

Treatment techniques are

can be monitored for generally “on-the-shelf” and

contaminants. with basic engineering can

be adapted to many groundwater contamination incidences. However, management

of treatment systems for

multiple contaminants and for

rapidly changing concentrations may prove to be difficult.

Performance data are not

available for groundwater

contamination applications

using ultrafiltration,

reverse osmosis, steam

stripping, ion exchange, and

electrodialysis.

Contaminant levels can be 4,5 Techniques are in the R&D

monitored in soil and water. stage with minimal commercial application. They

have a potentially limited

application to groundwater

due to practical constraints

such as the volume of

organisms required, reaction

kinetics, and the assimilative

capacity of organisms for

certain contaminants. In heterogeneous formations, access

to the entire contaminant

mass may be practically

impossible. Techniques are

most often applied to petroleum-related spills.

Same as biological degradation. 4,5 Techniques are in the R&D

stage with minimal commercial application. They

have a potentially limited

application to groundwater

due to practical constraints

including reaction kinetics

and reactivity of contami-
Table 35.—Corrective Action Techniques: Objectives, Performance, and Status-continued

Principal components

of uncertainty Measuring Development status

Technique Objective affecting performance performance Summary a Remarks

3. Water table To allow for

adjustment the aerobe

degradation of

contaminants

by lowering the

water table.

4. Natural

process

restoration

To allow for the

degradation and

dispersion of

contaminants in

the natural flow

system.

Management options

1. Limit/terminate To minimize the

aquifer use exposure of

possible users

to contaminated

groundwater.

2. Develop To provide a

alternative substitute water

water supply supply by

developing

● Potential for aerobic degradation is iimilea10 cenain

organic contaminants.

● Prediction of degradation

rates or processes,

● Prediction of contaminant

migration behavior; heterogeneities in aquifer conditions

reduce accuracy of predictions.

● The presence of non-degradable contaminants that,

although highly retarded,

continue to migrate at low

velocities.

● The ability to shut down

domestic wells due to possible public resistance.

● The ability to enforce usage

patterns in cases of environmental exposure (e.gp, to sport

fish or streams).

● Availability of water supply

alternatives, especially in

water-short areas which may,

in turn, limit the long-term

aiternative water growth of an area. -

sources.

nants. In heterogeneous

formations, access to the

entire contaminant mass

may be practicably impossible.

Contaminant concentrations 4, 5 The methods of pumping and

can be monioreci in soii anti

water. Underlying saturated

media can be monitored to

determine contaminant levels.

Downgradient levels of contaminants in soil and water can

be measured.

Exposure levels can be monitored; actual use patterns

over time can be determined.

Performance is also economic—e.g., it may be

cheaper to terminate use and

import water or develop

alternative supplies than to

treat supplies or otherwise

correct contamination.

Performance is mainly economic —e.g., it may be

cheaper to terminate use and

develop alternative supplies

or import water than to treat

supplies or otherwise correct

contamination.

gravity drainage used io aiier

water table levels are well

established. Evaluation of the

impacts of such adjustments

on contaminant degradation,

however, is not well defined

or established, and the technique is not conventionally

applied in plume management. Source isolation

is a possible application.

Raising the water table can

provide flushing benefits in

some cases.

5,6 Methods used to predict concentration reductions (e.g.,

solute transport models) are

not highly reliable. Monitoring

the actual attenuation of contaminants is a conventional

practice and performance can

be monitored.

6 Historically this is a common

response to aquifer

contamination.

6 In conjunction with Iimiting/

terminating aquifer use, alternative water supply development is a frequently implemented response.

ii

b

v

i3

3
Table 35.—Corrective Action Techniques: Objectives, Performance, and Status—continued

Principal components

of uncertainty Measuring Development status

Technique Objective affecting performance performance Summary a Remarks

3. Purchase

alternative

water supply

4. Source

removal

5. Monitoring

6. Health

advisories

7. Accept

increased risk

To provide a

substitute water

supply through

importation or

other purchases.

To remove

physically the

source of

contaminant ion.

To delineate and

track the migration (and concentrations) of

contaminants.

To limit the use of

contaminated

groundwater by

advising users

of contamination.

No action taken.

Reliance on imports, especially in water-short areas

where the supply may be

terminated or depleted.

Potential opposition to interbasin transfers.

Increased contaminant migration (e.g., via breaking of

drums or additional infiltration

during precipitation).

Availability of secure disposal

options.

Extent of contamination and

resulting costs. (See Excavation, above.)

Undetected plume migration

because of improper placement or sampling of wells.

Mistakes are difficult to detec

until a problem occurs or

backup wells around key

exposure points are installed.

. The ability to enforce usage

patterns in cases of environmental exposure (e.g., to

sport fish or streams).

 The ability to shut down

domestic wells due to possible public resistance.

● The ability to predict contaminant migration.

● Corrective action alternatives

can be more expensive as the

contaminant spreads out (i.e.,

a larger plume).

Performance is mainly economic—e.g., it may be

cheaper to terminate use and

develop alternative supplies

or import water than to treat

supplies or otherwise correct

contaminant ion.

Contaminant concentration

levels can be measured in

surrounding soils, aquifer

materials, and waters to

verify total removal.

Performance can be measured

by duplicating samples and

analyses. Use of qualified

personnel are essential for

proper well placement and

for the overall groundwater

quality investigation.

Exposure levels can be monitored; actual use pattern over

time can be determined.

Performance is also economic—e.g., it may be

cheaper to terminate use and

develop alternative supplies

or import water than to treat

supplies or otherwise correct

contamination.

Performance is often measured

in economic terms.

6

1

1,6

6

6

This is a frequently implemented response although

generally considered a shortterm solution.

Conventional construction

techniques are used for source

removal although substantial

increases in health and safety

precautions are required for

groundwater contamination

applications. Current activity

already involves significant

health and safety measures.

Conventional technology is

used for monitoring groundwater contamination problems

and conducting hydrogeologic

investigations. If methods are

used properly, reliable plume

delineation and migration

data can be generated (see

also ch. 5).

This option is a conventional

practice of State and local

health departments.

Historically this option is the

response to many contamination incidence. Impacts

on population are unclear.

aKey: 1—Technology is proven; performance data are available from applications to groundwater contamination problems.

2—Technology is proven In applications other than groundwater contamination; long-term performance data are unavailable for groundwater contamination.

3—Technology IS In R&D stage with respect to groundwater contamination applications, although proven for other applications; performance is generally unknown for groundwater contamination problems.

4—Application of technology has been limited to specific, narrowly def!ned site conditions.

5—Technology IS generally in R&D stage; results are unreliable.

6—Technology has been applied historically —e.g., before the development of regulatory programs and consideration of potential long-term impacts.

bwlthdrawal enhancement techniques that would be a “5” include surfactant injection.

cTreatmen t technologies that would be ,,2,, are ultrafiltration, r@v@rs@ osmosis, steam strlpplng, ion exchange, and elect rodlalysis.

SOURCE: Office of Technology Assessment.
192 . Protecting the Aation’s Groundwater From Contamination

STAGE OF DEVELOPMENT OF CORRECTIVE

ACTION ALTERNATIVES

The development status of alternatives is also

summarized in table 35. Generally, alternatives for

corrective action are commercially available. However, they have usually been developed for industrial and surface water uses, which do not require

the level of reduction, removal, and/or control of

substances that is necessary for groundwater contamination problems. For example:

containment methods were developed in the

construction industry for dewatering, foundation, and embankment applications;

withdrawal methods were developed for groundwater supply (i.e. , quantity) development and

for petroleum recovery;

treatment methods were developed for wastewater (i. e., surface water) and desalination applications; and

management options have generally been applied in the areas of wastewater (i. e., surface

water) treatment and water supply (i. e., quantity) development.

Some commercial alternatives require only minor modifications, if any, for groundwater contamination purposes. These alternatives include

some management options (e. g., the development

of alternative supplies) and, to a lesser extent, excavation if precautions are taken with respect to

materials handling and disposal.

Other commercial alternatives require continued

research and development before they can be applied effectively to contaminated groundwater. For

example, containment needs relate principally to

the permanence of installation—e. g., materials

compatibility, field validation procedures, quality

control, and leak detection (EPA, et al., 1983).

With respect to treatment, research and development is needed for radionuclides; viruses; certain

organic chemicals, including halogenated compounds; and complex mixtures of substances. Research also needs to continue on modifying existing

wastewater treatment facilities to handle a broader

spectrum of substances than they typically handle.

In general, the technologies for treating substances

in groundwater are likely to differ substantially from

those developed for contaminated surface water and

wastewater because of the marked differences

among the types and concentrations of substances

present.

Some innovative methods are being developed

specifically for application to groundwater contamination problems. For example, research and

development for in-situ rehabilitation originated in

the context of petroleum spills, and withdrawal

enhancement techniques are being developed in the

context of hydrodynamic control. Because innovative methods tend to be substance-specific, they are

likely to be useful only on a limited scale in the long

term.

Although some available technology and likely

developments appear promising for specific types

of contamination problems, technology alone cannot be expected to correct the full range of problems likely to be encountered. It will take years,

or even decades, of testing and monitoring to develop reliable performance data. Even then, the

knowledge gained will be site-specific.
Ch. 8—The Correction of Groundwater Contamination: Technologies and Other Alternatives ● 193

CHAPTER 8 REFERENCES

Geraghty & Miller, Inc., “The Fundamentals of

Ground-Water Quality Protection, ” New York,

1983.

SCS Engineers, ‘‘Survey of On-Going and Completed

Remedial Action Projects, ” prepared for Municipal

Environmental Research Laboratory, Office of Research and Development, U.S. Environmental Protection Agency, Cincinnati, OH, September 1981.

U.S. Environmental Protection Agency and the Department of the Army, “Barrier Workshop, ” A. W.

Briedenbach Environmental Research Center, Cincinnati, OH, Sept. 7-8, 1983.

Woodward-Clyde Consultants, Inc., “Corrective Action Alternatives for Ground-Water Contamination , draft report prepared for the Office of

Technology Assessment, August 1983.
Chapter 9

Federal Efforts To Correct

Groundwater Contamination
Contents

Page

Chapter Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ● 197

Statutory and Regulatory Provisions for sources of contamination . . . . . . . . . . . . . . . 197

Federal Government Experience . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 200

Chapter 9 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 202

TABLE

Table No. Page

36. Summary of Federal Corrective Action Provisions for Sources of

Groundwater Contamination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 198
Chapter 9

Federal Efforts To Correct

Groundwater Contamination —

CHAPTER OVERVIEW

Based on a review of statutory and regulatory

requirements, this chapter discusses the corrective

action programs of the Federal statutes and programs discussed in chapter 3. Information is presented on the sources of groundwater contamination requiring corrective action and the cleanup

standards specified under corrective action programs. An overview of Federal experience with corrective action is also provided. Specific corrective

act ions undertaken by either Federal agencies or

the responsible parties in response to regulatory or

court-imposed requirements were not reviewed for

this study.

The major conclusions of this chapter are:

● few Federal statutes provide for corrective

action,

● cleanup standards are generally not specified

in regulations, and

● Federal agency experience with such actions

is limited.

STATUTORY AND REGULATORY PROVISIONS

FOR SOURCES OF CONTAMINATION

Federal Government involvement in corrective

action efforts for contamination problems can be

characterized in one of three general ways:

1<

2.

3,

Federal agencies have developed regulatory

requirements (e. g., permit conditions) for corrective actions for specific sources of contamination (e. g., under the Resource Conservation and Recovery Act (RCRA)).

Federal agencies are mandated by statute to

undertake and finance corrective actions

related to specific sources of contamination

(e. g., under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) and the Uranium Mill

Tailings Radiation Control Act of 1978

(UMTRCA).

Explicit corrective action provisions are absent

but responsible parties may be required to

undertake corrective actions as a result of actions to enforce compliance with regulatory

requirements (e. g., drinking water regulations

and endangerment provisions).1 

Details of corrective action provisions for the OTA

source categories discussed in chapter 2 are prcsented in appendix G; the appendix contains information on the type of corrective action efforts

required under each statute (e. g., permit conditions

or federally funded cleanup activities) and on

specified cleanup standards.

Table 36 summarizes the corrective action provisions of the Federal statutes examined in this

 For example, under he rgrouncl Injection (;ont rol Prog-ram

established by the %tfc Drinking Water Act, the Env i mn mcnt al Protu t ion Agency may take cnforccrncnt action if there is a violation of”

drinking water regulations or if the health of persons is otherwise

adversely affcctcd. In add it ion, several statutes also contain prfnisions

that allow the Administrator of EPA to bring lawsuits if a( t ions prt\-

cnt or may present an ‘‘imminent and substant lal cndangcrmcnt

to human health or the cn~ironrncnt (e. g., Section 7003 of RCRA,

Section 1431 of SDW’A, Sections 504 and 311 (c) of (: WA, an(l Scrtion 106 of CEIR(; l. A).

197

38-799 0 - 84 - 10 : QL 3
Table 36.—Summary of Federal Corrective Action Provisions for Sources of Groundwater Contamination

Cleanup

standards

specified in

Statute Provisions regulations

Atomic Energy Acta

Clean Water Acta,b

Coastal Zone Management Act

Comprehensive Environmental Response,

Compensation, and Liability Acta

Federal Insecticide, Fungicide, and

Rodenticide Act

Federal Land Policy and Management Act

(and associated mining laws)

Hazardous Liquid Pipeline Safety Act

Hazardous Materials Transportation Act

Reclamation Acta

Resource Conservation and Recovery Act

None

Non e . . . . .

None

None

None

None

None

None

None

None

Background levels of

hazardous substances

(specified on a caseby-case basis), Maximum Contaminant

Levels for 14 contaminants established

under the Safe Drinking Water Act (if higher

than background), or

alternative concentration limits (specified

on a case-by-case

basis).
Table 36.—Summary of Federal Corrective Action Provisions for Sources of Groundwater Contamination—continued

Statute

Safe Drinking Water Act

Surface Mining Control and Reclamation

A c t

a

Toxic Substances Control Act

Uranium Mill Tailings Radiation

Control Act a

Cleanup

Standards

specified i n

Provisions regulations

No explicit corrective action requirements are specified for underground injection None

wells.

No explicit corrective action requirements are specified for mining operations on None

Federal lands.

Federally funded remedial actions are authorized by the Rural Abandoned Mine None

Program. d State grants are also provided for abandoned mine programs; States

establish reclamation priorities.

While the statute specifically addresses PCB disposal sites, no explicit corrective None

action requirements are established.

Federally funded corrective actions are authorized for specified inactive sites. The None for inactive sites.

statute explicitly lists those sites for which corrective actions are required.

Active sites are subject to the same requirements as surface impoundments under Standards for active sites

RCRA (except that corrective actions must be implemented within 18 months). are the same as RCRA

(Subtitle C) except that

levels for certain

radioactive substances

are also established. —

aThe statute authorizes federally funded remedial aCtiOn programs

bFederally funded corrective actions for oll SPlllS or leaks are authorized If there ,s a discharge Into flav/ga~/e waters (section 311) There are no cleanup standards, however, speclfled In the regulations This prOVISIOn

IS relevant to groundwater to the extent that groundwater and surface water may be Interconnected.

CA -release,, ,ncludes any spllllng, Ieaklng, pumplng, pour[ng, emlttlng, emptying, discharging, Injecting, escaping, Ieachlng, dumping, or dlsposlng. Sources explicitly exc/uded by law Include radioactive SiteS covered

by other laws and the normal application of fertilizers (see SectIon 101(22) of CERCL,%)

d T hls program ,s being phased out Although ,t provided for groundwater restoration, projects undertaken by the SOII Consewatlon Service have not directly addressed groundwater

SOURCE Off Ice of Technology Assessment
—

200 • Protecting the Nation’s Groundwater From Contamination

study.2 The following observations are made about

these provisions:

● Explicit corrective action provisions (e. g.,

groundwater protection standards) are not

specified for all sources of contamination. No

explicit corrective action requirements for

groundwater are established for sources in

OTA Categoric:; III. IV, V, and VI (refer to

ch. 2, table 5).

● Explicit regulatory requirements are specified

for some sources in Categories I and II:

—Category I: Land application of hazardous

wastes (under RCRA).

—Category II: Hazardous waste landfills, surface impoundments, waste piles, and land

treatment areas (under RCRA); radioactive

disposal sites (under the Atomic Energy

Act); and uranium mill tailings sites (active

sites under UMTRCA).

● Only two of the programs containing corrective action regulatory provisions establish explicit cleanup standards: RCRA and

UMTRCA. The standards are based on the

specified groundwater protection standard,

which includes the substances to be monitored,

concentration limits, the point of compliance,

and the compliance period (see app. E); corrective actions are not required beyond the

downgradient facility property boundary (see

app. G).

• Six Federal statutes authorize federally

funded remedial action programs but none of

the programs specifies cleanup standards.

‘Neither the National Environmental Policy Act nor the Water Research and Development Act are concerned with corrective action for

specific sources; they are thus omitted from table 36.

Photo credit: Office of Technology Assessment

Corrective action team wears protective clothing

as they drill a recovery well.

Rather, the selection of a remedy under these

programs (e. g., CERCLA and inactive sites

under UMTRCA) is based on protection of

health and the environment, costs, technical

feasibility, the uses of an aquifer, and availability of alternative water supplies.

FEDERAL GOVERNMENT EXPERIENCE

Federal agency experience with respect to the nated groundwater. Examples of federally funded

site-specific design and implementation of correc- corrective action programs follow:

tive actions is limited relative to the total number

of individual sites sources identified as requiring ● Remedial actions under CERCLA can be

remedial action. In addition, little of the experi- undertaken only at sites on the National Prience relates specifically to the cleanup of contami- orities List (NPL) (see app. G). As of Sep-
Ch. 9—Federal Efforts To Correct Groundwater Contamination ● 201

J“\

\

A.

.

L
202 • Protecting the Nation’s Groundwater From Contamination

tember 1984, 538 uncontrolled hazardous

waste sites were listed for priority action; EPA

projects that the NPL could eventually contain between 1,400 and 2,200 sites (EPA,

1984a, 1984b).3 Groundwater contamination

has been detected at 410 of the listed sites.4

As of July 1984, remedial actions had been

completed at on; y six sites on the NPL (U.S.

House of Representatives, 1984); and of these

six, none involved the cleanup of contaminated ●

groundwater. Engineering studies are underway or have been completed at 258 NPL sites,

and construction has begun at more than 60

sites using Federal funds (EPA, 1984a).

● Under its Installation Restoration Program

(IRP),5 the Department of Defense has inven-

‘EII’:! w,ts r{.pt)rtcd to hait’ ,idded 244 sitt. s to tht’ N“PI. on Oc t

‘J, 1084 ( Itr’l.dlln<q[)n , Posr, 1984), CERCI.A rt.quirtw that EPA up-

(I<it(> t h~> IX PI. ,il I{T<IS[ .innu<dl } (Stx’t ion 105 (B) ot t ht’ N’ational Cont ln~{,n{ \ Pl<In).

‘“1’hls figu r(. is based (III th c 546 sites original), placed on or prop{mxi for tht’ NP1. (EPA, 1 \ 83a, 1983b). A detailed assessment by

,In F,PA consultant ot (iata cwllcctcd for 86 (o!’ the 546) sites indicates

tb,lt on-site groundu atcr con arn in,lt ion has bet>n dctt’t-tcd at olcr 60

ptrccrlt o!’ thrm, off-site cent mlinat ion has been dctmted at m’cr 27

ptrc t>nt ot the SIICS ( Ikx)z.-Allcn & Hamilton, Inc. , 1983).

‘“l’hc IR P IS ,] IX)D prosr,inl slrnilar to CFIRC 1,A for hazardous

w ,iit<, sltcs (~n I X)D propcrr ~“

toried 911 installations and identified 200 that

may require remedial action. As of August

1983, site investigations to confirm contamination problems had been completed at 32 sites,

remedial actions at two sites had been completed, and an additional 16 actions were

under way. Data on the actual number of sites

contaminating groundwater were not available

(Daley, 1983).

UMTRCA led to the designation of 25 inactive uranium mill tailings sites in need of

remedial action. Preliminary engineering studies indicate that groundwater contamination

either has occurred or has the potential to occur at all of the sites. To date, the Department

of Energy has not selected remedial actions for

any of the designated UMTRCA sites, although options have been formally proposed

for two sites (Baublitz, 1983).

CHAPTER 9 REFERENCES

Baublitz, J., Director of Remedial Action Projects Di\.ision, Department of’ Energ~, personal communication, Aug. 27 and No\.. 18, 1983.

Booz-Allen & Hamiltorl, Inc., ‘‘Superfund Responses

to Threatened Drinking ~’ater Resources, Mana<gemen( of L’ ncont -oiled Hazardous Waste Sites

Confkr-ence, sponsored b). Hazardous Materials Control Research Institute, Washington, DC, No\’ember 1983.

1]~(.),, p. S., Director of’ Environmental policy, Depar-trnent of Defense, Te: t imony before the Subcommittee on In\.estigat ions and O\’ersight, Committee on

Public Works and Transportation, Aug. 10, 1983.

U.S. En\rironmental Protection Agency, press release

on National Priorit)’ List, Sept. 1, ] 983a.

LT. S. J3nl’ir-onmer)tal Protection Agenc?’, ‘ ‘Hazardous

$$’aste Sites, National Priorities List, Office of Solid

W’aste and Emergency’ Response, August 1983b.

U.S. Environmental Protection Agency, ‘ ‘Environmental INews, Office of Public Affairs, Sept. 12,

1984a.

U.S. En\’ironmental Protection Agency, ‘ ‘Background

u’

Information, National Priorities List Update #1,

September 1984b.

S. House of Representatives, ‘ ‘Investigation of the

En\rironmental Protection Agency: Report on the

President Claim of Executive Privilege Over EPA

Documents, Abuses in the Superfund Program, and

Other Matters, ” Subcommittee on O\ersight and In-

\’estimations of the Committee on Energy and Commerce, Report No. 98-AA, August 1984.

Washington Post, ‘ ‘EPA Adds 244 Sites to PriorityCleanup List, ” Oct. 3, 1984.
Chapter 10

State Efforts To Correct

Groundwater Contamination
Contents

Page’

Chapter Overview . . . . . . . . . . . . . . . . . . . . . . . . . . , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 205

State Corrective Action Programs for Sources . . . . . . . . . . . . . . . . . . . . . . . . ....0.... 2 0 5

Selecting Sites for Corrective Action. ....., , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 206

State Use, Preferences, and Problems With Corrective Action Alternatives . . . . . . . . 207

Use and Preferences. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 207

Problems With Corrective Action . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ... . . . . . . . . . . . 209

TABLES

Table No. Page

37. OTA State Survey Responses: Factors Used By States To Determine

Which Contaminated Sites To Address . . . . . . . . . . . . . . . . . . . . . . . . . ., . . . . . . . . . . . . 207

38. OTA State Survey Responses: Use and Preferences for Corrective

Action Techniques. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 208

39. OTA State Survey Responses: State Problems With Corrective

Action Techniques. . . . . . . . . . . . . , . . . . . , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 210

FIGURE

Figure No. Page

5. OTA State Survey Responses: Number of States With Programs To Correct

Groundwater Contamination From Selected Sources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 206
Chapter 10

State Efforts To Correct

Groundwater Contamination

CHAPTER OVERVIEW

State responses. to survey questions about their

efforts to correct groundwater contamination are

presented in this chapter. (See the section O T A

State Survey in ch. 4 for guidance in interpreting

survey result s.) The following topics are discussed:

● Sources of groundwater contamination for

which States have corrective action programs;

● priorities for selecting sites for action; and

● use of, preference for, and problems with corrective action techniques.

Additional information on State strengths, problems, and types of desired Federal assistance related

to corrective action is found in chapter 4.

The conclusions that follow are drawn from this

information.

Most States are working to correct contamination problems. But State efforts vary in terms of

the sources that are addressed and the process for

site selection, Further, State efforts to correct

groundwater contamination are generally at a n

early stage of development in that relatively few

States have formalized their approaches to corrective action.

The States are using a wide variety of techniques,

and many techniques are used together. With the

possible exception of source removal (for the cases

where sources can be identified and removed), the

States have few preferences among individual (or

categories of) corrective techniques. In making decisions, the States are concerned about the costs of

implementation and maintenance, the time required for implementation and achievement of

desired results, and the degree of certainty about

how well a technique will perform.

Most States have technical, legal, or institutional

problems in undertaking corrective action. Although the States want Federal assistance in overcoming technical and institutional problems, most

States do not want Federal assistance with their legal

problems, particularly those involving water rights.

Water rights issues often complicate the correction

of groundwater contamination problems.

STATE CORRECTIVE ACTION PROGRAMS

FOR SOURCES

Many States have programs to correct ground- the number of States with programs for a particuwater contamination from a variety of sources, as lar source and the pervasiveness of that source either

shown in figure 5. The highest number of States nationally or regionally. (See ch. 2 for a discussion

have programs to correct spills and accidents and of the location of sources. )

leaks from storage facilities and pipelines. Overall, more States have programs to correct sources In some States, correction programs are estabin OTA Categories 1, II, and 111 than to correct lished for sources although there are no detection

Categories IV-, V, and VI sources (refer to ch. 2, programs for those

table 5). There appears to be no correlation between is that the need for

same sources, The implication

corrective action is often iden205
206 ● Protecting the Nation’s Groundwater From Contamination

Figure 5.—OTA State Survey Responses: Number of States With Programs To Correct Groundwater

Contamination From Selected Sources

See fig. 2 for footnotes a through g.

SOURCE: Office of Technology Assessment.

tified as a result of complaints or other reports of

concern rather than from any kind of systematic

investigation. Sources for which the highest number of States have correction but not specific detec-

— — Detectio n

— Correctio n

--- - -. Prevention

tion programs include: spills and accidents, leaks

from storage facilities and pipelines, feedlots, application of pesticides and herbicides, abandoned

wells, waste piles, and subsurface percolation.

SELECTING SITES FOR CORRECTIVE ACTION

The States consider a variety of factors in their

decisions to undertake corrective action at one contaminated site as opposed to another, as shown in

table 37. Severity of the problem was identified by

the highest number of States, but State definitions

of severity vary. The States define severity in terms

of: the characteristics of the aquifer, substances, or

site; uses of the groundwater; impacts of contarnina-
Ch. 10—State Efforts To Correct Groundwater Contamination • 207

Table 37.—OTA State Survey Responses: Factors

Used By States To Determine Which Contaminated

Sites To Address

Number of

Factors States

Formal criteria . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

Severity of the problem . . . . . . . . . . . . . . . . . . . . . 45

Order in which contamination is detected . . . . . . 32

Public pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

Availability of special funding . . . . . . . . . . . . . . 37

Sites where source and responsible party

are identified . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

SOURCE: Off Ice of Technology Assessment

tion; reason for detection; and/or avail

water supply alternatives.

ability o f

Some States have developed formal criteria for

determining the sites to consider. Some use ranking systems developed by the Federal Government

(e. g., MITRE Hazard Ranking System); others

have developed their own ranking systems. Some

have no formal ranking systems but use State regulatory definitions (e. g., groundwater quality standards) to determine which sites warrant action.

Differences in selection criteria may result in very

different corrective action decisions among the

States—a site may qualify for corrective action in

one State, but a similar site in another State may

be of a lower priority. More detailed analysis of

State decisionmaking and resources (e. g., funds and

staff) is necessary to determine whether the differences in priorities and approaches to site selection

result in different levels of groundwater protection

among the States.

Most State efforts to correct groundwater contamination are in early stages of development. This

point is apparent from a lack of formal criteria for

selecting sites for corrective action in many States

and from the lack of formal criteria, written guidelines, or procedures in a majority of States-to: 1)

establish cleanup standards for corrective action (16

States have formalized approaches); 2) respond

when quality standards are violated (19 States have

formalized procedures, although the procedures do

not cover all potential sources of contamination);

and 3) respond when there is no quality standard

for the substances found in groundwater(17 States

have formalized procedures). Any formal criteria

that have been established differ among the States.

STATE USE, PREFERENCES, AND PROBLEMS

WITH CORRECTIVE ACTION ALTERNATIVES

Use and Preferences

The use of and preference for various techniques

to correct contamination are summarized in table

38. The most notable point about the table is that

the States are using or considering the use of a wide

variety of techniques. That many techniques are

used together is consistent with the technical limitations of these methods described in chapter 8. Most

States are working to correct at least some of their

identified groundwater contamination problems.

OTA did not obtain information on either the extent to which all known incidents are being addressed or the effectiveness of the corrective actions

that are being undertaken.

Preferences for specific techniques were noted by

40 States. Four States did not specify preferences

for individual techniques, noting that preferences

depend on such site conditions as source, substances,

and aquifer characteristics. Two States said that it

is too soon to know which techniques they prefer.

No individual technique is preferred by many

States. Source removal (a management technique)

is preferred by the highest number. The actual

number of States preferring it may be higher because the OTA survey did not ask specifically about

the use of this option.

Preferences for techniques relate primarily to the

low cost and/or the expected effectiveness of a tech-
208 ● Protecting the Nation’s Groundwater From Contamination

Table 38.-OTA State Survey Responses: Use and Preferences for Corrective Action Techniques

Number of States: Number of States:

With preference With preference

Technique Using for usea

Technique Using for usea

Containment:

Slurry wall . . . . . . . . . . . . . . . . . . . . . 29

Sheet pile . . . . . . . . . . . . . . . . . . . . . 10

Grouting . . . . . . . . . . . . . . . . . . . . . . 18

Geomembrane . . . . . . . . . . . . . . . . . NQb

Clay Cutoff . . . . . . . . . . . . . . . . . . . . NQ

Liner c . . . . . . . . . . . . . . . . . . . . . . . . . 47

Natural containment . . . . . . . . . . . . 36

Surface sealing . . . . . . . . . . . . . . . . . 35

Diversion ditches . . . . . . . . . . . . . . . 41

Hydrodynamic controld . . . . . . . . . . 24

Technique not specified . . . . . . . . . 2

Total number of

States responding . . . . . . . . . 48

Withdrawal:

Pumping . . . . . . . . . . . . . . . . . . . . . . 44

Gravity drainage . . . . . . . . . . . . . . . . . . . ..31

Withdrawal enhancement . . . . . . . . NQ

Gas ventinge . . . . . . . . . . . . . . . . . . . 29

Excavation . . . . . . . . . . . . . . . . . . . . . 41

Technique not specified . . . . . . . . . 3

Total number of

States responding . . . . . . . . . 47

Treatment:

Skimming . . . . . . . . . . . . . . . . . . . . 34

Filtration . . . . . . . . . . . . . . . . . . . . . 28

Ultrafiltration . . . . . . . . . . . . . . . . . . 13

Reverse osmosis . . . . . . . . . . . . . . 17

Air stripping . . . . . . . . . . . . . . . . . . 34

Steam stripping . . . . . . . . . . . . . . . NQ

Precipitation/clarification/

coagulation . . . . . . . . . . . . . . . . . . NQ

15

5

1

NQ

‘ o

3

11

17

0

0

1

2

NQ

NQ

Treatment (cont'd):

Ion exchange . . . . . . . . . . . . . . . . . . 25

Adsorption . . . . . . . . . . . . . . . . . . . . 34

Electrodialysis . . . . . . . . . . . . . . . . . NQ

Chemical transformation . . . . . . . . . NQ

Biological transformation . . . . . . . . NQ

Incineration . . . . . . . . . . . . . . . . . . . . NQ

Technique not specified . . . . . . . . . 7

Total number of

States responding . . . . . . . . . 43

In-situ rehabilitation:

Biological degradation . . . . . . . . . . . 20

Chemical degradation . . . . . . . . . . . 20

Water table adjustment . . . . . . . . . . 40

Natural process restoration . . . . . . . 33

Technique not specified . . . . . . . . . 3

Total number of

States responding ........, 47

Management:

Limit/terminate aquifer use . . . . . . .

Develop alternative water supply . .

Purchase alternative water supply .

Municipal treatment . . . . . . . . . . . .

Point of end-use treatment. . . . . . .

Source removal ... , . . . . . . . . . . . . .

Monitoring. . . . . . . . . . . . . . . . . . . . .

Health advisories . . . . . . . . . . . . . . .

Accept increased risk . . . . . . . . . . .

Technique not specified . . . . . . . . .

Total number of

States responding . . . . . . . . .

38

44

32

NQ

32h

NQ

47

46

NQ

1

49

0

0

NQ

NQ

NQ

NQ

14

16

10

5

6

1

1

g

0

11g

8

3

NQ

1

21

a Nine states noted that they had few or no preferences for techniques—either because of having relatively I ittle experience with impiement ing corrective act iOns Or because

preferences were site-specific. ‘our additional States had no preferences but did not provide an explanation, Some States listed more than one preference.

bNQ—OTA did not specifically question the States about this Option.

C Re~wnses Primarily reflmt the use of liners for prevention of groundwater contamination (&g,, in the design of new facilities), liners are rarely used for corrective action purposes,

doTA used the term plume man;lgement in the questionnaire to the States rather than hydrodynamic control.

e OTA used the term gas migration control in the questionnaire to the States rather than 9as ventln9.

f These treatment techniques ar{ listed under Management to reflect who is responsible for the action and whether treatment occurs before Or after Water distribution,

gAlthough OTA did not specifically question the States about use of this option, some Stales noted a preference for it.

hseveral States noted that this v(as a private option and not one that the State would imPlement.

SOURCE” Office of Technology Assessment.

nique or combination of techniques. These reasons

were given for all categories of corrective action

techniques. Other reasons given, mostly for preferring management options, relate to the lack of

either resources or effective alternatives to clean up

the contamination, the relatively short time usually available for implementation, and the absence

of clear State authority to implement other techniques.

Agencies within a State may have different preferences for corrective action techniques. These differences may reflect agency missions, knowledge

of technical options, and the problems that each

confronts. For example, in one State, the health

agency prefers to develop alternative sources, the

water quality agency prefers withdrawal and treatment techniques, and the industry regulatory agency

prefers containment options.
Ch. 10—State Efforts To Correct Groundwater Contamination ● 209

Problems With Corrective Action

Thirty-one States described problems with implementing corrective action techniques. Of the

States that did not describe problems, five specifically noted that experience is too limited to evaluate

the techniques. Other problems are more closely

related to detection and hydrogeologic investigations (e. g., with contaminant transport models and

identifying sources of contamination and responsible parties) and are discussed in chapter 7.

Table 39 classifies the problems associated with

corrective action alternatives as technical, institutional, and legal and provides examples of each.

General findings are:

●

●

The States experience a variety of problems

in implementing techniques for corrective

action, and different States have different

problems.

More States noted technical problems than

legal or institutional problems: This situation

contrasts with the reported problems with

hydrogeologic investimations, which are mostly

institutional (see ch. 7). However, specific legal

problems with water rights and general authority were also listed by a relatively large number of States regarding corrective action.

-7’

b

—

,

A . . -–

Photo credlf State of F/or/da Department of Envfronrnenfa/ Regulation

When contaminated drinking water wells are closed,

water must be obtained from other sources.
210 ● Protecting the Nation’s Groundwater From Contamination

Table 39.-OTA State Survey Responses: State Problems With Corrective Action Techniques

Number of States Types of problems Examples of problems

Technical problems:

10 High cost of techniques

6 Site constraints associated

with techniques

1 Difficulties implementing techniques

4 Lack of knowledge on setting standards

for performance

4 Uncertainty over effectiveness of

techniques

3 Adverse impacts of some techniques

3 Intensive data and monitoring requirements

21 Total States reporting technical problems

Institutional problems:

6

3

3

3

1

2

11

Legal problems:

10

8

2

16

Lack of funds

Inadequate technical expertise

Inadequate regulations and program

 implementation

Lack of interagency coordination

Unavailability of equipment

Public resistance

Total States reporting institutional problems

Lack of authority—water rights

Lack of authority—other

Liability concerns

Total States reporting legal problems

●

●

●

●

●

●

●

●

●

●

●

●

●

●

Expense of treatment techniques for removing some

organics

Expense of developing alternative water supplies

Expense of correcting salt-water contamination in

agricultural areas

Techniques unavailable for karst environments

Limitations on achievable withdrawal rates

Difficulties in designing and installing liners

Lack of information on health and environmental

impacts of many contaminants

Inability to predict technical performance

Increased contaminant migration caused by well

closings and cessation of pumping

Impacts on air quality caused by air stripping

Difficulties in identifying sources of contamination

Continued presence of contaminants after corrective

action has been undertaken necessitates

continued monitoring

Scope of State activities constrained

Lack of staff with sufficient technical knowledge

Lack of standards for determining cleanup

objectives

Inadequate enforcement

Overlapping authority among agencies

Difficulties in coordinating with Federal agencies

Shortage of drilling rigs and lack of geophysical

equipment

Public unwillingness to use water after cleanup

● Difficulties in obtaining information on water use

and pumping schedules

• Inability to control or restrict water uses that may

influence alternatives involving pumping

● Difficulties in obtaining alternative water supplies

● Lack of regulatory jurisdiction over potential

sources of contamination (e.g., underground

storage tanks)

● Difficulties in obtaining property access

● Potential for damage suits if State supplies

alternative water supply (e.g., bottled water)

that turns out to be contaminated

31 Total number of States noting problems

SOURCE Off Ice of Technology Assessment
Prevention
Chapter 11

Federal Efforts To Prevent

Groundwater Contamination
Contents

Page

Chapter Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 215

Prevention of Contamination by Sources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 215

Scope of the Groundwater Resource Addressed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 215

Types of Programs and Sources Addressed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 223

Performance Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 223

Aquifer Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 225

Regulating the Production and Use of Potential Contaminants. . . . . . . . . . . . . . . . . . . 226

Toxic Substances Control Act . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 226

Federal Insecticide, Fungicide, and Rodenticide Act . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 228

Chapter 11 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 231

TABLE

Table No. Page

40. Federal Provisions To Prevent Groundwater Contamination From Sources . . . . . . . . . 218
Chapter 11

Federal Efforts To Prevent

Groundwater Contamination

CHAPTER OVERVIEW

Activities authorized by Federal statutes related

to the prevention of groundwater contamination arc

described in this chapter. They address prevention

in terms of:

● sources of contamination ;

● groundwatcr recharge areas; and

● potential contaminants.

The Federal Government does not have a formal plan or cornprehensive strategy to prevent contamination. For cxample, programs for sources—

for design and operation, siting, and post-closure—

do not use a consistent definition of the groundwater resource to be protected and do not systematically address the contamination potential of

sources. The program for protecting recharge areas

is not comprehensive because the designation of

such areas is optional and only certain potential}’

contaminating projects are restricted. To date, the

application of provisions that regulate the production and use of potential groundwater contaminants

to prevent contamination has been limited.

PREVENTION OF CONTAMINATION BY SOURCES

Federal statutes and programs address prevention of conntamination from sources in terms of three

types of factors:

1. the scope of the groundwater resource covered

(e. g., groundwatcr in general or drinking

water supplies);

2. the specific’ sources addressed and the type of

program (e. g., for design and operation—

these may be either mandator}’ or voluntary);

a n d

3. the performance requirements specified (e. g.,

for the siting of’ sources and their closure).

Table 40 summarizes the provisions of Federal programs in terms of’ these factors. Federal monitoring and corrective action requirements are noted

in the table but they are discussed in chapters 6 and

9. respectively.

1 F( JU r statutes Included I n [h. 3 are not applicable [(J [his discus-

~it)n and [hus are not Included in table 40: NEP.4 and WRDA do

n( J[ (Jitdbl ish rcqu i mments for SOLI rces; C ERC 1..4 and the Reclamat Ion A( t ( RA) are not in{ Iuded because they provide for remedial act I(]ni, not pretentlte measures

Scope of the Groundwater

Resource Addressed

The scope of groundwater resources covered by

Federal programs is an important consideration in

preventing groundwater contamination. However,

Federal programs are not consistent in defining the

resource covered and the extent of degradation permitted. Table 40 (column 3) summarizes the way

in which groundwater is addressed by Federal

programs:

● The scope of groundwater resources covered

by Federal programs is not consistent.

—Four programs (authorized by AEA for lowlevel waste sites, FLPMA and associated

mining laws, SMCRA, and TSCA) address

groundwater in general.

—Two programs are concerned with the uppermost aquifer (authorized by RCRASubtitle C and UMTRCA).

—Three programs cover underground drinking water supplies (authorized by RCRASubtitle D, SDWA, and CWA-Section

405).

215
Table 40.-Federal Provisions To Prevent Groundwater Contamination From Sources

Type of

Publication program and

date of

Corrective

Relationship sources Siting

Statute

Monitoring action Post-closure

regulations to groundwater addressed requirements requirements b requirements requirements

Atomic Energy NRC regulations Radioactive material reAct (10 CFR 61)–12/27/82 leased into ground-

(EPA has not promul- water must not exceed

gated environmental levels specified in the -. -.--.: -- ---- 4 -.4-,

plulcwtlul I ala Iualua) I“cyuiiliicn”ls

NRC proposed regula- Geologic repositories

tions (10 CFR 60)– include the operations

718181, 46 FR 35280 area and the geologic

EPA proposed environ- setting (the geologic,

mental protection stand- hvdrologic. and geoards (40 CFR 191)-

12/29/82, 47 FR 58196d

Clean Water Act

— Section 201 EPA Criteria—2/n/76,

41 FR 6190 (EPA construction grant regulations are specified in

40 CFR 35)

chemical system-s that

provide isolation of the

waste).

Groundwater is separated

into three categories

concerning the land

application of wastewater.

— If groundwater is a

potential drinking

water supply, the

National Interim

Drinking Water

Regulations (NIDWRs)

must not be exceeded. If background levels are

higher than NIDWRs,

they must not be

exceeded.

Design and operating

standards are specified

for low-level waste

disposal sites.

Design and operating

standards are specified for geologic repositories for high-level

radioactive wastes.

Disposal sites must provide sufficient depth to

the water table to prevent groundwater intrusion into me wastes.

Hydrogeologic units used

for disposal shall not

discharge groundwater

to the surface within

the disposal site.

Other requirements

relate to seismic and

other tectonic

activity, flooding, location of natural

resources, and population growth and

development.

The geologic setting

must exhibit structural,

tectonic, hydrogeologic,

geochemical, and geomorphic stability.

Groundwater travel

times (prior to waste

deposition) through

the geologic setting

(i.e., the area that

provides isolation of

wastes) to the accessible environment

must be at least

1,000 years.

Criteria for best practicable None

waste treatment

technology for land

application of wastewater must be met by

applicants for construction grant funds

(for sewage treatment

works).

Yes Yes Active institutional controls

(e.g., monitoring) may not

be relied on

for more than

100 years

(the exact

period to be

determined

by the NRC

on a caseby-case

basis).

Yes None Disposal systems must be

designed to

prevent releases of

specific

amounts of

radioactive

material for

10,000 years

after disposal.

Active institutional controls

must not be

relied on

beyond a few

hundred years.

Yes Yes None
Table 40.-Federal Provisions To Prevent Groundwater Contamination From Sources— continued

Type of

Publication program and

date of

Corrective

Relationship sources Siting

Statute

Monitoring act ion Post-closure

regulations to groundwater addressed requirements requirements requirements requirements

Clean Water Act — If groundwater is used

– Section 201

(cent’d)

as a drinking water

supply, the conditions

above must be met

(except that levels

for biological contaminants must not

be exceeded in the

supply if water is

not disinfected).

— If groundwater is

used for purposes

other than drinking

water, criteria are

established on a

case-by-case basis.

– Section 208 EPA State grant regula- The program is oriented

tions (40 CFR 35, Sub- to surface water; howpart G)–5/23/79 ever, States are authorized to undertake

groundwater activities

to the extent practicable.

— Section 311 EPA regulations The program is oriented

(40 CFR 112)–12/11/73 to surface water protection; groundwater

is not directly

addressed.

– Section 404 EPA regulations Protection is oriented to

(40 CFR 230)–12/24/80 wetlands protection;

groundwater is not

directly addressed.

None None None None

Funds are authorized for Not Not Not Not

States to develop water applicable applicable applicable applicable

quality management

plans. State plans provide for development

of activities (e.g., Best

Management Practices)

related to certain

non-point sources.e

Spill Prevention and

Countermeasure Control

(SPCC) Plans must be

prepared for above-

-ground and underground

tanks of a specified

size containing oil.

The plan must describe

design and operating

conditions.

Permits must be obtained General guidance is pro- None

to dispose of dredged vialed that relates

or fill material. Guide- to the selection of disIines to be applied in posal sites such that

the review of proposed the potential for erosion,

discharges are specified. slumping, or /caching

of material into surrounding aquatic ecosystems will be

reduced.

None None
Table 40.-Federal Provisions To Prevent Groundwater Contamination From Sources— continued

Type of

Publication

date of

program and Corrective

Relationship sources Siting Monitoring action Post-closure

Statute regulations to groundwater addresseda

requirements requirements requirements requirements

– Section 405

Coastal Zone

Management

Act

EPA Criteria

(40 CFR 257)-9/13/79

NOAA State grant

regulations

(15 CFR 923)–3/28/79

Federal Insecticide,

Fungicide, and

Rodenticide Actf

– Section 3 EPA regulations

(40 CFR 162)–7/3/75

— Section 19 EPA regulations

(40 CFR 165)–5/1/74

Federal Land

Policy and

Management Act

— Mineral Leasing BLM regulations

Act of 1920 and (43 CFR 23)–1/18/69

Materials Act

of 1947

Criteria for determining

unreasonable adverse

effects do not explicitly address groundwater.

Regulations refer to

water systems; groundwater is not explicitly

addressed.

The use of pesticides

that may cause unreasonable adverse effects on the environment can be restricted

or prohibited.

Recommended procedures are established

for storage areas for

pesticides.

Regulations specify that Requirements for mining

a plan of operations of leasable minerals on

must be developed that Federal lands are

includes measures to to be specified in the

prevent or control plan of operations.

groundwater pollution.

State and Federal water

quality standards must

be met.

None

Not

applicable

Use restrictions may

be established for a

pesticide.

Facilities should be

located where flooding

is unlikely and where

soil and hydrogeologic

characteristics will

prevent contamination

of any water system

by runoff or percolation.

Operations may be prohibited or restricted in

areas if the regulatory

authority determines

that water quality

will be lowered

below State standards

or levels set by DOI.

Groundwater is

not explicitly

mentioned.

Yes Yes None

Not Not Not

applicable applicable applicable

None None

None None

None

None

None None Performance

bond must be

filed to cover

reclamation

activities.

w

●
Table 40.—Federal Provisions To Prevent Groundwater Contamination From Sources— continued

Type of

Publication program and Correct we

date of Relationship sources Sltinq Monitong action Post-closure

Statute regulations to groundwater addressed requirements requirements requirementsc

requirements

— U.S. Mining BLM regulations

Laws (43 CFR 3800)–3/3/80

— Geothermal BLM regulations

Steam Act (30 CFR 270)–6/27/79

and 6/30/829

Hazardous Liquid DOT regulations

Pipeline Safety (49 CFR 195)–7/27/81

Act as amended

Hazardous DOT regulations

Materials (49 CFR Subtitle B,

Transportation Subchapter C)–4/15/76

Act as amended

Resource Conservation and Recovery

Act

– Subtitle C EPA regulations

(40 CFR 264)–7/26/82

Note: Final regulations

have not been promulgated for covered

underground tanks or

for some open burning and detonation

sites.

Groundwater is not directly addressed in the

regulations; however,

State and Federal water

quality standards must

be met.

Regulations specify that

a plan of operations

must be developed

which includes measures to prevent or

control groundwater polIution. State an d

Federal water quality

standards must be met.

The objective of the regulations is to prevent

leakage. However,

groundwater is

not directly

addressed.

The objective of the

regulations is to

protect against risks

to life and property.

However, groundwater

is not directly

addressed.

Requirements for min- None None None Performance

ing of locatable min- bond must be

erals on Federal lands filed to cover

are to be specified in reclamation

the plan of operations. activities.

Requirements for develop- None

ment of geothermal

steam on Federal lands

are to be specified in

the plan of operations.

Design and operating None

standards are specified

for pipelines used to

transport hazardous

liquids.

Design and operating

standards are specified

for transportation of

hazardous materials

and hazardous wastes.

None

Regulations specify that Design and operating Facilities must not be

hazardous substances standards are specified located in areas subentering groundwater for hazardous waste ject to flooding

(in the uppermost treatment, storage, or seismic conditions.

aquifer) must not ex- and disposal facilities

ceed background (e.g., landfills, surface

levels, the Maximum impoundments, waste

Contaminant Levels for piles, and land treat14 constituents specified ment areas).

by the National Interim

Drinking Water Regulations (if higher than

background), or alternative concentration

limits (established on

a case-by-case basis)

at the compliance point.

Yes

None

None

Yes

None None

None None

None None

Yes Specified

activities

(e.g., groundwater monitoring and operation of

Ieachate collection

system) must

be continued

for 30 years

after closure

unless the

time period is

increased or

or decreased

by the regulatory authority.
Table 40.-Federal Provisions To Prevent Groundwater Contamination From Sources— continued

Type of

Publication program and Corrective

date of Relationship sources Siting Monitoring

Statute

action Post-closure

regulations to groundwater addressed a

requirements requirements requirements requirements

– Subtitle D

Safe Drinking

Water Act -

– Part C

(UIC Program)

Surface Mining

Control and

EPA regulations

(40 CFR 257)–9/13/79

EPA regulations

(40 CFR 146)–6/24/80

as amended

Note: Regulations have

not been promulgated

for certain wells.1

OSM regulations

(30 CFR 816 and 817)–

Reclamation Act revised 9126183

(Regulations were first

published in 1979)

The criteria specify that

for underground drinking water sources,

background levels or

the National Interim

Drinklng Water Regulations (if higher than

background) must not

be exceeded beyond

the application boundary or an alternative

boundary established

on a case-by-case basis.

Regulations specify that

it must be demonstrated

that activities will not

be conducted in a

manner that allows

movement of contaminants into an underground source

of drinking

water (defined as an

aquifer or its portion

that supplies any

public water system

or contains sufficient

water to supply a

public water system

and that currently

serves as a drinking

water supply or

contains fewer than

I0,000mg/1 TDS).

Aquifers may be exempted if they are

not currently drinking

water supplies, cannot

and will not be supplies in the future, or

contain 3,000-10,000

mg/1 TDS and are not

reasonably expected

to supply a public

water system.

Regulations specify that

groundwater quality

must be protected by

handling earth materials

and runoff in a manner

that minimizes acidic.

Funds are authorized for

States to develop

optional State solid

waste programs.

Specified Federal

criteria for sanitary

landfills must be met

by State program.

Design and operating

standards are specified

for underground injection wells.

Requirements are specified in operating permit

for surface coal mining and underground

coal mining (for

surface effects).

None None None None

None

None

Yes

Yes Yes

None Noneh

Performance

bond must be

filed to cover

reclamation

activities.
Table 40.-Federal Provisions To Prevent Groundwater Contamination From Sources— continued

Type of

Publication program and

date of

Statute

Relationship sources

regulations to groundwater addressed

Toxic Substances

Control Actf

— Section 6

Uranium Mill

Tailings

Radiation

Control Act

EPA regulations

(40 CFR 761)–5/31/79

NRC regulations

(10 CFR 40)–10/3/60

EPA regulations

(40 CFR 192)–10/7/83,

48 FR 45926

toxic, or other harmful

infiltration to groundwater systems and by

managing excavations

and other disturbances

to prevent and control

the discharge of pollutants into groundwater. State and

Federal water quality

standards must be

met.

The objective of regulations is to ensure

against an unreasonable risk of injury to

health or the environment (e.g., water) from

the manufacture, processing, distribution,

use, or disposal of a

chemical substance or

mixture.

Same as RCRA–

Subtitle C (except that

levels for certain

radioactive

substances are

specified).

Design and operating

standards are specified

for PCB disposal sites.

Design and operating

standards are

specified for uranium

mill tailings disposal

sites (same as RCRA

Subtitle C requirements for surface impoundments).

Corrective

Siting Monitoring action Post-closure

requirements requirements requirements requirements

Facilities must be located

in areas of low to moderate relief and must

avoid floodplains, shoreIands, and groundwater

recharge areas.

Bottom of landfill must

be 50 feet from

historical high water

table.

NRC requirements

specify that the selection process must

consider hydrologic

and other conditions

as they contribute to

continued immobilization and isolation of

contaminants from

usable groundwater

sources.

EPA regulations do not

establish siting requirements.

Yes None Operating

records must

be retained

for 20 years

after closure.

Yes Yes Long-term

surveillance is

specified by

NRC on a

case-by-case

basis.

EPA regulations

require that

sites be

developed to

be effective

for 1,000 years

to the extent

reasonable

achievable

and in any

case for at

least 200

years.

asee table 13 and app, H for additional information on sources, types of programs, and design and operating requirements.

%ee table 30 and app. E for additional information on monltonng requirements.

csee table 36 and app. G for additional information on correctwe action Pmw.ions

%he provisions cited in the table are EPA’s proposed protection standards. eprovisions aPPIY t. non.point sources Including irrigation return flows, agricultural sources, Iwestock areas, mine rUnOff, saltwater Intrusion, and construction actlvltY

f See the text for a more detailed discussion of FIFRA and TSCA.

gRegulatlons for the Geothermal Steam Act were redesignated, with minor revisions, as 43 CFR 3260 on Sept. 30, 1983.

~here are plugging requirements at closure.

I Regulations have not been promulgated for Class IV and V wells under the UIC Program; see app. H and 40 CFR 146.

SOURCE: Office of Technology Assessment
222 ● Protecting the Nation’s Groundwater From Contamination

–One program (under Section 201 of CWA)

separates groundwater into three categories—drinking water supplies, potential

drinking water supplies, and groundwater

used for other purposes—with different

standards for each category.

—The programs authorized by five statutes

do not directly address groundwater in any

way (CWA—Sections 311 and 404, CZMA,

FIFRA, HLPSA, and HMTA).

—The requirements for selecting geologic repositories for high-level radioactive wastes

(under AEA) include surrounding hydrogeologic systems as part of the repository.

● The extent of degradation permitted by Federal programs is not consistent.

—Under the Subtitle C program of the Resource Conservation and Recovery Act

(RCRA, which addresses the uppermost

aquifer), the Environmental Protection

Agency (EPA) may establish alternative

concentration limits on a case-by-case basis

(instead of requiring that groundwater contamination not exceed background levels or

Maximum Contaminant Levels). EPA regulations specify the factors that must be considered in approving the alternative concentration limits.2 However, decisions are to be

made by permit writers on a site-specific

basis.

—Under the Underground Injection Control

Program of the Safe Drinking Water Act

(SDWA), certain aquifers maybe exempted.

Thus, underground injection into those

aquifers is not controlled.

‘See 40 CFR 264.94(b).

Photo credit: CECOS International

Liners and Ieachate control systems are included in the design and operating requirements for hazardous waste landfills

and surface impoundments under Subtitle C of RCRA. This photograph shows a synthetic and clay-lined hazardous waste

disposal facility prior to use.
Ch. n-Federal Efforts To Prevent Groundwater Contamination . 223

Types of Programs and

Sources Addressed

The principal type of program related to the prevention of contamination from sources is for design and operation. As indicated in chapter 2, potential sources of contamination have different

characteristics for releasing substances (e. g., point

v, non-point discharges) which necessitate different

design specifications and operating procedures to

prevent groundwater contamination, Programs

may be either mandatory or voluntary; and they

are specified for particular sources of contamination. Design and operating requirements are summarized in table 40 (column 4) and described in

detail in appendix H in relation to each Federal program and OTA source categories (refer to ch. 2,

table 5). The following observations can be made

about the types of programs that have been developed. (Note that the technical adequacy of these

programs has not been evaluated in this study. )

● Mandatory design and operation requirements

apply to subsets of sources within Categories

I, II, III, and V. As noted in chapter 3, the

sources addressed by programs with mandatory requirements are, for the most part, associated with hazardous wastes or other toxic

materials.

● With the exception of certain mining activities and the application of certain pesticides,

sources in Category IV are not subject to mandatory requirements. However, Best Management Practices or recommended procedures

have been developed for some of these sources.

● There are no mandatory requirements for any

sources in Category VI.

It is significant that many of the programs’ requirements were established fairly recently. Table

40 (column 2) indicates that the majority of regulations were published within the past 5 years.

Thus, the impacts of some of these programs on

the prevention of groundwater contamination cannot yet be ascertained. Further, despite the fact that

programs have been authorized by Federal legislation for certain sources, regulations specifying

design and operating (as well as monitoring and

corrective action) requirements have not been promulgated for certain sources. These sources

include:

. covered underground tanks (under RCRA);

. injection wells used to dispose of hazardous

wastes into or above underground sources of

drinking water and all other injection wells except those used for the following purposes: disposal of hazardous or radioactive materials and

other wastes (e. g., municipal or industrial) beneath underground sources of drinking water;

wells used in association with oil and gas production; and wells used for in-situ or solution

mining (under SDWA);

. open burning and detonation sites (under

RCRA); and

● low-level radioactive disposal sites (under

AEA).

3

In addition, the purview of the Hazardous Liquid Pipeline Safety Act (HLPSA), which establishes

requirements for interstate pipelines (used to transport petroleum products and anhydrous ammonia),

includes the storage of liquids incidental to their

movement by pipeline. Although regulations have

been promulgated for pipelines, the Department

of Transportation has not established requirements

for storage facilities (e. g., tanks).

Performance Requirements

This study also examined the extent to which

Federal programs address the prevention of groundwater contamination with performance requirements for siting new sources and post-closure. As

indicated in table 40 (column 5), siting provisions

for new sources are specified by six programs: highand low-level radioactive waste programs under the

Atomic Energy Act (AEA); pesticide storage provisions under the Federal Insecticide, Fungicide,

and Rodenticide Act (FIFRA); mineral mining provisions for leasable minerals under the Mineral

Leasing Act; the hazardous waste program (Subtitle C) under RCRA; the PCB disposal requirements under the Toxic Substances Control Act

(TSCA); and the Nuclear Regulatory Commission

3The Nuclear Regulatory Commission has issued licensing regulations for these facilities. However, EPA has not issued environmental

protection standards.
224 ● Protecting the /Vation’s Groundwater From Contamination

Photo credits: U.S. Environmental Protection Agency

Open burning and detonation of waste explosives are addressed under RCRA but regulations have not yet been promulgated.

These photographs show white phosphorus drums being prepared for disposal . . . and their subsequent detonation.

requirements for uranium mill tailings sites established under the Uranium Mill Tailings Radiation

Control Act (UMTRCA). Of the six programs, the

requirements established under RCRA and the

Mineral Leasing Act do not explicitly address the

protection of areas vulnerable to groundwater conlamination. 4

Provisions that address any contamination that

may occur after a source is no longer in use (’‘postclosure’ are also important for the prevention of

contamination. Table 40 (column 8) summarizes

these provisions .

5 Post-closure provisions are specified for a limited number of sources: disposal facilities for hazardous and certain radioactive

substances and mining operations. There is also

an inconsistency between the requirements for hazardous waste facilities and high-level radioactive

waste sites: in spite of the fact that many of the

chemicals found in hazardous waste disposal facilities are non-degradable, a post-closure period of

only 30 years has been set. G In comparison, it has

been proposed that high-level radioactive waste

disposal sites which contain radioactive substances

that do degrade over time (e. g., half-lives of

radioactive substances range from tens to more than

millions of years) must be designed to prevent releases for 10,000 years. 7

There are two additional points about the postclosure requirements in table 40 with respect to specific

1.

2.

sources:

There are no post-closure monitoring requirements established for PCB disposal facilities. Thus, any groundwater contamination that may occur following closure is not

likely to be detected.

Specific requirements have not been established for uranium mill tailings sites. Postclosure provisions will be required only at the

discretion of the regulatory authority.

4Proposed RCRA regulati >ns issued by EPA on Dec. 18, 1978 (43

FR 59000) did contain siting requirements with respect to aquifer

recharge areas, but the provi iions were not adopted in the final regulations issued by the agency (40 CFR 264. 18).

‘In this assessment, reclamation activities conducted as part of mining operations are considered post-closure provisions.

‘Although the post-closure period can be extended by the regulatory authority if necessary, it is possible that a site will appear to be

secure at the end of the 30-year period but subsequently release

substances into groundwater.

7

47 FR 58196, Dec. 29, 1982.
Ch. 1 l—Federal Efforts To Prevent Groundwater Contamination ● 225

AQUIFER PROTECTION

A second approach of Federal statutes related to

the prevention of groundwater contamination is to

protect recharge areas. The Sole Source Aquifer

provision of the Safe Drinking Water Act, Section

1424(e), allows the Administrator of EPA to designate the aquifers that serve as sole or principal

drinking water sources and to prevent any commitments of Federal financial assistance to projects that

may create significant hazards to public health by

contaminating such aquifers.

The Sole Source Aquifer provision ’does not establish a comprehensive program for protecting

aquifer recharge areas. The process for designating sole source aquifers is optional, and only certain projects are restricted from receiving Federal

financial assistance. In addition, funding decisions

are based on findings regarding the significance of

the hazard posed to human health.8

EPA issued proposed regulations in September

1977 establishing procedures for designating sole

source aquifers and reviewing projects proposed in

these areas (final regulations have not been published by EPA).9 The proposed regulations define

several key terms used in this section of the statute:

● A sole or principal source aquifer is defined

as one which supplies 50 percent or more of

the drinking water for an area. The proposed

regulations also specify six factors that must

be considered in deciding whether to designate

a sole source aquifer:

1.

2.

3.

4.

5.

6 .

the availability of alternative sources of

drinking water;

the size of the area and population served

by the aquifer;

the susceptibility of the aquifer to contamination through the recharge zone;

the location of the aquifer;

the number of public water systems using

water from the aquifer, the number of people served by the systems, and the treatment

provided by the systems; and

such other factors as are deemed relevant.10 

●

●

A significant hazard to public health means

any level of a contaminant: a) which causes

or may cause the aquifer to exceed any Maximum Contaminant Level set forth in any promulgated National Primary Drinking Water

Regulation at any point where the water may

be used for drinking purposes or which may

otherwise adversely affect human health, or

b) which may require a public water system

to install additional treatment to prevent such

adverse effects.

Federal financial assistance includes any financial benefits provided directly as aid to a project by a department, agency, or instrumentality of the Federal Government in any form,

including contracts, grants, and loan guarantees. Actions or programs carried out by the

Federal Government itself (e.g., dredging performed by the Army Corps of Engineers) and

actions performed for the Federal Government

by contractors (e. g., construction of roads on

Federal lands) are not included. Federal financial assistance is limited to benefits earmarked

for a specific program or action and awarded

directly to the program or action .11

As of July 1984, EPA had designated 17 sole source

aquifers (see EPA, 1983, 1984).

1145 FR 5 I fjz 1. EPA has indicated that it ‘‘will not be concerned

with reviewing on an individual basis, small isolated commitments

of financial assistance such as individual home mortgage loans.

12De~ignated aquifers are:

1. Edwards Aquifer, TX (petition received 1 /3/75, designated

12/16/75)

2. Nassau/Suffolk Counties Long Island, NY (petition received

1/21/75, designated 6/21178)

3. Maryland Piedmont (petition received 10/1/75, designated

8/27180)

4. Northern Guam (petition received 11/20/75, designated 4/26/78)

5. Fresno County, CA (petition received 8/9/76, designated

9/10/79)

6. Spokane-Rathdrum Prairie, WA-ID (petition received 10/4/76,

designated 2/9/78)

7. Biscayne Aquifer, FL (petition received 5/8/78, designated

10/1 1/79)

8. Buried Valley, NJ (petition received 1/16/79, designated 5/8/80)

9 Cape Cod, MA (petition received 3/4/81, designated 7/31/82)

— 10. Whidbey Islandj-WA (petition received 4/31~81, designated

8The Sole Source Aquifer provision originated as a floor amendment to the Safe Drinking Water Act. See Hemphill, 1976.

’42 FR 51620, Sept. 29, 1977.

1042 FR 51623.

4/6/82)

11. Camon Island, WA (petition received 4/31/81, designated

4/6/81)

12, Kings/Queens Counties, NY (designated 1/24/84)
226 ● Protecting the Nation’s Groundwater From Contamination

After an area is designated as having a sole or

principal source aquifer, the Regional Administrator may review any project located in that area

for which Federal financial assistance is proposed.

The proposed regulations specify the review procedures that must be followed by EPA. Anyone

(footnote 12 continued)

13. Ridgewood, NJ (desi\:nated 1/24/84)

14. Upper Rockaway River Basin, NJ (designated 1/24/84)

15. Upper Santa Cruz and Avra-Altar Basin, AZ (designated

1/24/84)

16. Nantucket Island, MI\ (designated 1/24/84)

17. Block Island, RI (ales gnated 1/24/84)

ljIf an area is designated, ~pA must identify the boundaries of the

recharge zone or streamflow !iource zone (or portions thereo~ through

may petition EPA to review a project, or EPA may

initiate the review. In addition, Federal agencies

are required to maintain a list of projects in the

recharge or streamflow zone of a designated aquifer

for which environmental impact statements (under

the National Environmental Policy Act, NEPA) will

be prepared. EPA has stated that “the process of

project review pursuant to Section 1424(e) will be

integrated as fully as possible with the review of

Federal actions subject to NEPA."14

which contamination could affect the area and the water bcdy or bodies

which contact the recharge zone. 42 FR 51623.

‘+42 FR 51621.

REGULATING THE PRODUCTION AND USE

OF POTENTIAL CONTAMINANTS

There are two Federal statutes that provide

for regulation of the production and use of potential groundwater contaminants: the Toxic Substances Control Act and the Federal Insecticide,

Fungicide, and Rodenticide Act, Both require submission of data on the environmental effects of

chemicals and authorize the regulation of potential groundwater contaminants. To date, however,

their use for the prevention of contamination has

been limited.

Toxic Substances Control Act

The Toxic Substances Control Act (TSCA) provides for the regulation of chemical substances and

mixtures whose manufacture, processing, distribution in commerce, use or disposal may present an

unreasonable risk of Injury to health or the environment, 15 Unlike other statutes analyzed in this

study (e. g., RCRA and SDWA), TSCA does not

focus on specific sources of groundwater contamination. However, because it encompasses all aspects

of a chemical’s pathway through society, including

use and disposal, TSC A has the potential for directly addressing groundwater contamination (see ch.

1’” ‘Environment’ is defined to include water, air, and land and

the interrelationship which exists among and between these media and

all living things (Section 3(5)). ‘‘Groundwater’ is not explicitly mentioned.

2 for a discussion of pathways). In addition, TSCA

provides a mechanism for obtaining data on the

properties of certain chemicals associated with

sources of groundwater contamination.

Two provisions of TSCA are most relevant to

the prevention of contamination.

1.

2.

Section 5 requires that manufacturers or importers of ‘new’ chemicals submit a premanufacture notice (PMN) to EPA 90 days before

the substance enters commerce. The PMN is

to include sufficient data for EPA to determine

whether the manufacture, processing, distribution in commerce, use, or disposal of the

new chemical—or any combination of such

activities—will present an unreasonable risk

of injury to health or the environment.16

Section 6 provides for regulation of the manufacture, ‘processing, distribution in commerce, use, or disposal of chemical substances

or mixtures that present or will present an un16TSCA does not define ‘ ‘unreasonable risk. In 1979, EPA stated

that it “intends to balance the magnitude of risks and social benefits

associated with a chemical substance. In doing this, EPA will consider the seriousness of the risk (including the nature, extent, and reversibility of the adverse effects), the availability of alternatives to the

substance and their associated risks, and the benefits (economic and

otherwise) which accrue to society from the production and use of the

substance. 44 FR 16243, Mar. 16, 1979.
Ch. Ii—federal Efforts To Prevent Groundwater Contamination . 227

reasonable risk of injury to health or the environment. 17

Section 5. TSCA specifies that the PMN subm it ted to EPA by a manufacturer must include information regarding the chemistry of the new

substance, proposed uses, the amounts to be manufactured or processed, the byproducts, the num -

ber of’ workers to be exposed and the duration of

exposure, and methods of disposal. General classes

of information are also to be submitted to EPA,

inclucl ing any available test data in the possession

or control of the manufacturer related to environmental and health effects and a description of any

other data, insofar as known to the manufacturer

or reasonably ascertainable.18 EPA can then take

one of four actions following the review of a PM N’:

1 ) allow the substance to be manufactured without restriction; 2) allow the substance to be manufactured for specified uses (EPA would have to be

notified about other uses); 3) if a decision about

unreasonable risk cannot be reached because of the

lack of’ in information, delay the manufacture, processing, distribution, use, or disposal until additional

information is developed; or 4) regulate the manu facture, processing, distribution, use, or disposal

of t the substance.

A previous OTA study reviewed the information contained in the 740 PMNs submitted to EPA

from July 1, 1979 to June 1981 and in June 1982

(0TA, 1980). The study found that 62 percent of

the PMNs reported all the information specified by

TSCA (e. g., chemistry, proposed uses, amounts,

byproducts, exposure, and disposal methods).

However, only 10 percent of the PMNs reported

any information from tests used to estimate environrnental effects. Physical-chemical data most

directly related to predicting the behavior of chemicals in groundwater- density, vapor pressure,

solubility (in water), and partition coefficient-were

reported, respectively, on 19 percent, 24 percent,

1 T@her Sec.[ions of TSCA provide for: the compilation of an in-

~’ento~ of existing chemicals manufactured or processed in the United

States and the recording and reporting of certain health and environmental data (Section 8); the development of test rules on health and

environmental effects of existing chemicals (Section 4); the commencement of ci~il actions when chemical substances pose an imminent

hazard (Section 7); and the authorization of State grants for establishment and operation of programs to prevent or eliminate

unreasonable risks (Section 28).

18 Sect~on 5(d)(l).

42 percent, and 4 percent of all PMNs (OTA, 1983;

Gough, 1983), In addition, although approximately

50 percent reported toxicity information, only 17

percent had any test information about the 1ikelihood that the chemical could cause cancers, birth

defects, or mutations.

In the absence of data on the physical-chemical

properties of chemicals used to assess environmental

effects under the PMN review process, EPA relies

on estimates of chemical properties and the use of

computer models to determine whether the use of

a new chemical may affect groundwater. 9

Section 6. This section provides EPA with broad

authority to address sources of groundwater contamination directly by regulating the use or disposal

of a chemical substance or mixture .20 To date, EPA

19EpAs office of Toxic Substances has undertaken two projects

to support the premanufacture review process. One involves a computer program, CHEMEST, which estimates certain chemical properties on the basis of molecular structure information (Arthur D Little, 1983). The program is capable of providing estimates of the

following properties: volubility in water; the soil adsorption coefficient;

bioaccumulation or the bioconcentration factor (in fish); the activity

coefficient; the boiling point; the vapor pressure; the rate of volatilization from water; and Henry’s Law Constant.

The second project involves the development of two models used

to assess the behavior of a chemicat in soil and groundwater. One mmiel

predicts movement through the unsaturated zone (Bonazountas, et

al. , 198 1), and the other simulates the transport of contaminants

through an aquifer (Yeh, 1981). Information compiled on 70 locations in the United States is the data base for these computer modeling efforts (Versar, 1983).

Zosect ion 6 requires the Administrator of EPA to take one or more

of the following actions if there is a reasonable basis to conclude that

the manufacture, processing, distribution in commerce, use, or disposal

of a chemical substance or mixture (or any combination of activities)

presents or will present an unreasonable risk of injury to health or

the environment:

1.

2.

3.

4.

.5.

6.

7.

prohibit or limit the amount of such substance or mixture which

can be manufactured, processed, or distributed;

prohibit or limit the amount of such substance or mixture which

can be manufactured, processed, or distributed for a particular

use or a particular use in excess of a specified level;

require that such substance or mixture be accompanied by clear

and adequate warnings and instructions with respect to its use,

distribution in commerce, and/or disposal;

require manufacturers or processors of such substance or mixture to make and retain records of certain processes;

prohibit or otherwise regulate any manner or method of commercial use of such substance or mixture;

prohibit or otherwise regulate the manner or method of disposal

of such substance or mixture provided that State (or other level

of government) laws or requirements are not violated, and require notification of the appropriate level of government; and

direct manufacturers or processors of such substance or mixture

to give notice of such unreasonable risk of injury and replace

or repurchase such substance or mixture.

The factors which must be considered in promulgating a Section

6 rule include:
228 ● Protecting the Nation’s Groundwater From Contamination

has regulated four chemicals or groups of chemicals under Section 6 1 ) fully halogenated chlorofluorocarbons, 2) waste materials containing tetrachlorodibenzo-p-dioxin (TCDD), 3) asbestos, and

4) polychlorinated biphenyls (PCBs) .2’ Only the

PCB regulations involve disposal provisions related

to preventing groundwater contamination. However, one State in responding to OTA’s State

survey noted that the PCB disposal regulations are

not being strictly enforced by EPA and that TSCA

does not provide for the transfer of regulatory

authority to the States. The TCDD requirements

prohibit the disposal of wastes containing TCDD

by a particular chemical company (which is under

court order to undertake remedial actions at a hazardous waste site under RCRA); the company is

required to store and monitor the wastes until a

long-term solution is found.

Federal Insecticide, Fungicide,

and Rodenticide Act

The overall thrust of the Federal Insecticide,

Fungicide, and Rodenticide Act (FIFRA), which

regulates pesticides in the United States, is to ensure that the use of a pesticide will not cause unreasonable adverse effects on the environment. 22

FIFRA defines an unreasonable adverse effect on

the environment as ‘‘any unreasonable risk to man

or the environment, taking into account the economic, social and environrmental costs and benefits

of the use of any pesticide. FIFRA contains two

A.

B.

c.

D.

the effects of such substance or mixture on health and the magnitude of the exposure of human beings to such substance or

mixture;

the effects of such substance or mixture on the environment

and the magnitude of the expc)sure on the environment to such

substance or mixture;

the benefits of such substance or mixture for various uses and

the availability of subs itutes for such uses; and

the reasonably ascertain,ible economic consequences of the rule,

after consideration of the effect on the national economy, small

business, technological ilmovation, the environment, and public

health (Section 6(c)(l)).

Zlsee 40 CFR 762, 40 CFR 775, 40 CFR 763, and 40 CFR 761,

respectively. Procedures for ndemaking under Section 6 are specified in 40 CFR 750. Congress explicitly directed EPA to promulgate

disposal and labeling requiren-ents for PCBS within 6 months of the

effective date of TSCA and to phase out their use over a 2-year period;

the PCB disposal requirements established by EPA with respect to

monitoring, correction actions, and design and operation are discussed

in chs. 6, 9, and 11, respecti~ ely.

Zzsee Section 2(bb). Like TS(3A, FIFRA does not explicitly include

groundwater in the definition of environment.

principal provisions relevant to the prevention of

groundwater contamination: 1) Section 3 provides

for the registration of all pesticides based on the

submission of data specified by EPA and for the

classification of pesticides for general or restricted

use; and 2) Section 6 authorizes EPA to suspend

and cancel the registrations of pesticides that cause

unreasonable adverse effects on the environment. 23

Section 3. Section 3 of FIFRA requires the

registration of all pesticides. In addition to registering new pesticides, EPA is also mandated to review all existing registrations to ensure that they

meet current requirements, 24 There are 40,000

pesticides (containing some 1,400 active ingredients

in 578 generic categories) now registered by EPA.

For a pesticide to be registered, FIFRA requires

determinations including that it will function as intended without unreasonable adverse effects on the

environment, and when used in accordance with

widespread and commonly recognized practice, it

will not generally cause unreasonable adverse effects on the environment.25

EPA issued final regulations establishing basic

registration requirements in July 1975.26 The

pesticide registration regulations enumerate three

risk criteria for EPA use in determining whether

a pesticide causes an unreasonable adverse effect:

1) acute toxicity in humans, other mammals, or

birds, 2) chronic toxicity in humans, test animals,

or endangered species, or population reductions in

non-target organisms, and 3) lack of emergency

treatment for ameliorating the toxic effects of a

pesticide in people.27 The regulations did not idenZsother sections of FIFRA authorize EPA to: certify pesticide applicators to ensure that they are competent with respect to the use and

handling of restricted pesticides (Section 4); establish procedures and

regulations for the disposal or storage of packages and containers of

pesticides or excess amounts of pesticides (Section 19); formulate a

National Monitoring Plan (Section 20); and authorize certain State

responsibilities (Sections 24 and 26).

ZfThe 1972 amendments to FIFRA established the re-registration

requirement. Subsequent amendments have attempted to streamline

the re-registration process by authorizing EPA to develop generic standards for pesticide ingredients. These standards are used to review both

new and existing registrations of individual products containing those

ingredients. As of April 1984, EPA had issued 75 generic standards.

Anticipating that generic standards are needed for 400-500 categories of pesticides, EPA is currently developing such standards at a rate

of 25 per year (Auerbach, 1984).

25 Section 3(c)(5).

m40 CFR 162, Subpart A.

v40 CFR 162.1 l(a)(3).
Ch. 1 I—Federal Efforts To Prevent Groundwater Contamination • 229

F’hoto credit: State of F/orida Department of .Environrnenta/ Regulation

Pesticides may be introduced into groundwater from non-point sources such as land application, as well as from point sources

of hazardous wastes (e.g., landfills), non-hazardous wastes (e.g., residential disposal), and non-waste products (e.g., storage tanks).

tify’ the types of data needed to satisfy the statutory registration requirements. However, EPA de-

\’eloped guidelines between 1975 and 1981

describing such data requirements. In November

1982, EPA proposed regulations that reorganized

the guidelines and listed the specific types of data

and information needed to support a pesticide

registration. 28

Guidelines published by EPA as a companion

document to the 1982 proposed regulations identify the following characteristics of a pesticide as

being most pertinent to an evaluation of its potential to contaminate groundwater: leachability; adsorption/desorption characteristics; resistance to

chemical, photochemical, and biological degradation; volubility in water; and volatility (EPA,

1982).29 For the assessment of these characteristics,

2847 FR 53192, No\.. 24, 1982.

Zgq’hls FJpA document supports 40 C FR 158, Subdivision N, proposed Data Requirements for the Registration of Pesticides, 47 CFR

53192.

EPA’s proposed regulations require the submission

of data resulting from degradation, metabolism,

mobility, dissipation, and accumulation studies.30

Section 3(d) of FIFRA requires EPA to classify

pesticides (as part of the registration process) for

general or restricted use. A pesticide is classified

for restricted use:

. . . if, the Administrator determines that the

pesticide, when applied in accordance with its

directions for use, warnings and cautions and for

the uses for which it is registered, or for one or more

of such uses, or in accordance with a widespread

and commonly recognized practice, may generally

cause, without additional regulatory restrictions,

unreasonable adverse effects on the environment,

including injury to the applicator. .. .31

3040 c FR 158, 130, 47 FR 53205. F.nvironmcnta] fate data requirements were issued as a public draft in 1978 and again in October 1980; see 47 FR 53194 and EPA, 1982.

~lsection 3(d)(l)(C).

38-799 0 - 84 - 12 : QL 3
230 . Protecting the Nation’s Groundwater From Contamination

The statute provides I hat if a pesticide is classified

for restricted use on the basis of human health

hazards caused by acute dermal or inhalation toxicity, the pesticide can be applied only by a certified applicator. 32 If a pesticide is classified for restricted use because it may cause an unreasonable

adverse effect on the environment, the Administrator of EPA must require that it be applied by a certified applicator or be subject to such other restrictions as may be provided by regulation.33

The regulations regarding restricted use classifications do not state the specific types of actions

that could be included in the ‘‘other restrictions’

category. 34 However, the legislative history of

FIFRA indicates that other restrictions might include geographic controls over the use of a pesticide

(Costello, 1983).35 The regulations do specify that

a pesticide product classified for restricted use must

bear a label that contains the statements of the restricted use classification and directions for use;36

these label restrictions could be used to prohibit the

use of certain pesticides in specified areas (e. g.,

recharge areas) or to specify application procedures

that prevent ground water contamination (e. g.,

limiting the amounts or the rate of application)

(Severn, et al., 1983).37

sZS~CtiO~ s(d)(l)(c)(i). A Celtifiecl applicator must be comPetent in

the use and handling of pesticides. EPA regulations identify competency standards. They include a demonstration of practical knowledge with respect to the envil onmental effects of the use or misuse

of pesticides. See 40 CFR 171.

Sssection 3(d)( 1 )( C)(Ii).

S+see 40 CFR 162.30. The regulations indicate, however, that the

risk criteria specified by 40 CFR 162. 11(a)(3) are to be used in determining whether the use of a xsticide should be restricted.

sSThe report of the Senate Committee on Agriculture and Forestry

explained that although a third type of classification (permit only) was

rejected, EPA was not constrained “from regulating the quantity to

be applied for a given use for i particular application to a particular

crop in a given area at a given time, from limiting the number of applications, or from prohibiting the use thereof. . . ‘‘ (U.S. Senate,

1972).

3640 CFR 162.30(q).

srLabe] restrictions have be m imposed for the use of aldicarb On

Long Island, NY, in res~onst to a reauest from the manufacturer.

Section 6. This section of the act allows the EPA

Administrator to suspend and cancel the registration or change the registration of a pesticide (e. g.,

from general to restricted use). A suspension order may be issued by EPA if it is determined necessary for preventing an imminent hazard during

the time required for cancellation or change in

classification proceedings .38

A pesticide registration can be canceled or its

classification changed if the pesticide causes

unreasonable adverse effects on the environment

when used in accordance with widespread and commonly recognized practice or if its labeling or other

material required for submission to EPA does not

appear to comply with the provisions of FIFRA.39

Although actions taken under Section 6 are based

on a finding of unreasonable risk to humans and

the environment (i. e., a determination that acute

toxicity or chronic toxicity exceed criteria or that

there is no emergency treatment), information regarding the potential of a pesticide to leach through

the soil into groundwater can be factored into

EPA’s assessment of exposure to pesticides that do

meet the risk criteria .40

Sasection 6(C){ 1 ). An imminent hazard is defined in FIFRA, in %Ction 2(l), as ‘‘a situation which exists when the continued use of a

pesticide during the time required for a cancellation proceeding would

be likely to result in unreasonable adverse effects on the environment

or will involve unreasonable hazard to the survival of a species declared

endangered by the Secretary of the Interior under Public Law 91-135. ”

Sgsection 6(b)(1). pursuant to Section 6(a)(1) of FIFRA, a pesticide

registration shall also be canceled at the end of any 5-year period which

begins on the date of its registration unless a continuation is requested.

+osee for example, 48 FR 46234, Oct. 11, 1983 (46238). It is alSO

important to underscore the fact that a finding of unreasonable risk

under FIFRA involves a process that weighs health risks against the

benefits of continued use of the t)esticide.
Ch. Ii—federal Efforts To Prevent Groundwater Contamination ● 231

CHAPTER 11 REFERENCES

Arthur D. Little, Inc., “User’s Guide, CHEMEST, A

Program for Chemical Property Estimation, prepared for U.S. Environmental Protection Agency

and the U.S. Army Medical Bioengineering Research and Development Laboratory, revised March

1983.

Auerbach, J., Office of Pesticides and Programs, U.S.

Environmental Protection Agency, personal communication, Apr. 19, 1984.

Bonazountas, M., and J. M. Wagner, ‘‘SESOIL—A

Seasonal Soil Compartment Model, ” Arthur D. Litde, Inc. (Washington, DC: Office of Toxic Substances, U.S. Environmental Protection Agency,

contract No. 68-01-6271, 1981).

Costello, G., “Groundwater Contamination Through

Application of Pesticides: Existing Federal Controls, Congressional Research Service, Jan. 21,

1983.

Gough, M., Senior Associate, Office of Technology

Assessment, Testimony before the Subcommittee on

Toxic Substances and Environmental Oversight,

Committee on Environment and Public Works, U.S.

Senate, July 28, 1983.

Hemphill, J. B., ‘ ‘Section 1424(e) of the Safe Drinking

Water Act: An Effective Measure Against Groundwater Protection?’ Environmental Law Reporter

6:50121, November 1976.

Office of Technology Assessment, The Information

Content of Premanufacture Notices, Background Paper (Washington, DC: U.S. Government Printing

Office, OTA-H-BP- 17, April 1983).

Severn, D. J., C. K. Offutt, S. Z. Cohen, W. L. Burnam, and G. J. Burin, ‘ ‘Assessment of Groundwater

Contamination by Pesticides, ” Hazard Evaluation

Division, Office of Pesticide Programs, U.S. Environmental Protection Agency, June 7, 1983 (prepared for the FIFRA Scientific Advisory Panel

Meeting, June 21-23, 1983, Arlington, VA).

U.S. Environmental Protection Agency, “Pesticide

Assessment Guidelines, Subdivision N, Chemistry:

Environmental Fate, ” Environmental Fate Branch,

Hazard Evaluation Division, Office of Pesticide Programs, NTIS PB83- 153973, Oct. 18, 1982.

U.S. Environmental Protection Agency, “Status of the

Sole Source Aquifer Program, ” Office of Drinking

Water, July 6, 1983.

U.S. Environmental Protection Agency, ‘ ‘Sole Source

Aquifer Designations to Date, ” Office of Drinking

Water, May 1, 1984.

U.S. Senate, 92d Cong., 2d sess., “Legislative History

of the Federal Environmental Pesticide Control Act

of 1972, Public Law 92-516, ’ Senate Report No.

838, 1972.

Versar, Inc., “Acquisition of Climatological Data and

Soil Data and Creation of SESOIL and TOX-SCREEN

Parameter Data Files, ” prepared for U.S. Environmental Protection Agency, contract No. 68-01-6271,

May 9, 1983.

Yeh, G. T., “Analytical Transient One-, Two-, and

Three-Dimensional Simulation of Waste Transport

in an Aquifer System, ORNL-5602, Oak Ridge

National Laboratory, Oak Ridge, TN, March 1981.
Chapter 12

Overview of the States

and Prevention
Contents

Chapter Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ● ● . ● . 

State Prevention Approaches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Source Programs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...4..... .. .. ... ... ...4 ...$

Aquifer Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Impact Reduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Chapter 12

Figure No.

References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .””””..”””

FIGURE

6. OTA State Survey Responses: Number of States With Programs To Prevent

Groundwater Contamination From Selected Sources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Page

235

235

237

239

239

240

Page

238
Chapter 12

Overview of the States and Prevention

CHAPTER OVERVIEW

In this chapter, State responses to survey questions about their activities to prevent groundwater

contamination are briefly described. 1 (See the section OTA State Survey in ch. 4 for guidance in interpreting survey results. ) Approaches that States

use for prevention are highlighted along with programs for sources, aquifer protection, and impact

reduction.

In summary, the States are using a variety of approaches to prevent groundwater contamination.

They give priority to and are developing and implementing programs for prevention of contamina-

‘ ( ;I\ en the OTA stud) focus on afrcady contain inated groundwatct-,

the ( Y1’A ~urit.} did not question the State\ on their use, preferences,

,md pr( Jjlems w Ith spm ifi( techniques for preix. ntion. For more detailed

a( { OU nt \ ( ~f w.1(”( tml SI ate proqrarns wc Henderson, et al. , 1984

tion from particular sources, especially waste-related point sources.

States’ problems with prevention and desires for

Federal assistance are discussed in chapter 4. The

chapter describes the States’ problems with prevention as mostly institutional. The States noted a lack

of prevention programs, deficiencies in some types

of programs, and a lack of resources to implement

existing institutional mechanisms. The technical

adequacy of prevention mechanisms is also a concern. The States want Federal assistance for prevention mostly in the form of funding and research

and development on control techniques for additional sources. They also want the Federal Government to assist information exchange among the

States and to improve Federal prevention programs

that they perceive as unsuccessful.

STATE PREVENTION APPROACHES

The States use a variety of approaches to prevent contamination—directed at sources, aquifer

protection, and impact reduction. These approaches,

which vary among the States, consist of components

including: siting requirements; design and operating requirements (e. g., discharge requirements,

Best Management Practices, construction standards, and closure standards); land use controls; and

deed restrictions.

Programs have already been implemented in

many States. In others, programs are being developed. Legislation is required in a small number of

States (fewer than 10) to authorize programs that

they are working to develop.

Different components of State prevention programs may be mandatory or voluntary. For example, mandatory permit requirements may apply to

facility siting and/or design and operation; through

technical assistance and public education activities,

a State may encourage voluntary use of Best Management Practices to minimize the potential for contamination from particular activities and facilities.

Groundwater classification systems, general policies about the degradation of groundwater, and/or

the protection of public health and the environment

guide implementation of prevention programs in

some States. Classification systems have both advantages and disadvantages when used for this purpose (as described by Miller, 1984). Advantages

relate primarily to establishment of a formal mechanism for determining where and to what extent

water quality protection measures are applied. Disadvantages relate primarily to technical difficulties

in establishing classification boundaries (e. g., insufficient data) and policy conflicts in defining water

quality objectives for various classifications (e. g.,

235
236 ● Protecting the Nation’s Groundwater From Contamination

Grou

\

1’)

I

/

/

/

I

I I

II

//’ J

\

Low density

\

\-/’

/ ’

nGA

\

\

I

II

I

I

I

/

I

/

/

/

I

I

I

/

//

/

EAl

— --- Drainage boundary

D

GAA Public water supply well fields

GA Suitable for drinking water use

— –-.— Groundwater classification boundary

c) Surface water classification

GC Waste-receiving zones

Credit: Geraghty & Miiier, 1933

Groundwater classification schemes are used to facilitate decisions about groundwater

quality protection in some States. The example shown illustrates the groundwater

classification system applied by the State of Connecticut.
Ch. 12—Overview of the States and Prevention ● 237

acceptability of allowing a resource to be degraded

in certain areas). 2 Even if classification systems are

not used as a formal basis for decisionmaking about

siting or the design and operation of facilities, the

aquifer information that is associated with these

classifications usually contributes to prevention

decisions as well as decisions on priorities for detection and correction. Twenty-three States classify

groundwater on the basis of various characteristics

useful for making prevention decisions. For example, classifications are based on: the natural quality

differences in aquifers which affect water use (e. g.,

total dissolved solids); characteristics that may make

‘For a ~etaile~ discussion r)f advantages and disadvantages of

~r~undlvater classification s~stcms and a description of some State

pr~~ramst see Ma~nuson, 19B 1. Additional State classification pro-

~rams are ciescribml in Pye, ct al., 1983 and API, 1983.

aquifers vulnerable to contamination (e. g., water

table v. confined aquifers); characteristics that affect the development of water supplies (e. g., high

v. low yield); and variations in population, average use rate, contamination problems, and availability of alternative groundwater resources.

Source Programs

Prevention programs that the States have either

implemented or are developing are related primarily to sources. Ten States explicitly commented on

the limited coverage of their prevention activities—

that programs do not address all recognized sources

of potential contamination. For example, one State

noted that many of its programs are applicable only

to landfills, wastewater lagoons, and land applicaPhoto credit: State of F/orida Depatimefst of Enviromnenta/ Re@dation

State public education programs are being designed to promote awareness of improper disposal methods that can result

in groundwater contamination. Some programs authorize the collection of hazardous wastes

from small quantity generators, including households.
238 ● Protecting the Nation’s Groundwater From Contamination

tion of sewage sludge, and are not applicable to

agricultural activities:;. In general, waste-related

point sources are addressed in more States than

non-waste and non-point sources.

As shown in figure 6, more States have programs

for prevention of contamination from various sources

—and give priority to these programs—than for

detection or correction of contamination. Also,

more States have prevention programs for and give

priority to sources in OTA Categories I (e. g., injection wells) and II (e. g., surface impoundments)

than in Categories III, IV, V, and VI. Not all facilities and/or activities for each of these source types

are covered in State prevention programs. For example, in one State, well construction standards

apply only to drinking water wells; in another, such

standards apply to all wells in artesian (confined)

aquifers; and in a third State, although standards

apply to all wells, they are not strictly applied to

private wells or to agricultural wells.

Permit programs for design and operation of different sources may be oriented to the overall performance of a facility or related to certain technology requirements. For example, facilities that

discharge substances to groundwater may have to

satisfy groundwater quality standards. Technology

Figure 6.—OTA State Survey Responses: Number of States With Programs to Prevent Groundwater

Contamination From Selected Sources

See fig. 2 for footnotes a through g.

SOURCE: Office of Tachnolog’/ Assessment.
Ch. 12—Oveview of the States and Prevention ● 239

I%fo credit U S Enwronrrrenta/ Protecffon Agency

Voluntary replacement of underground gasoline storage tanks is one technique that many

States rely on to prevent groundwater contamination.

requirements may include, for example, the use of

liners and leachate collection systems for landfills

and septic tanks of specified sizes.

Aquifer Protection

A few States have programs that address the protection of aquifers and/or recharge areas. For example, in some States where sole source aquifers

have been designated, State or local restrictions

have been placed on certain activities (see ch. 11).

One State provides funds for municipalities to purchase land for aquifer protection.

Impact Reduction

Although most State activities appear to be directed at preventing (or minimizing the potential

for) groundwater contamination, some States have

programs to prevent adverse impacts associated

with potential contamination. For example, in one

State solid waste facilities must be recorded on property deeds. This measure is intended to avoid the

unknowing purchase of former landfills.
240 • Protecting the Nation’s Groundwater From Contamination

CHAPTER 12 REFERENCES

American Petroleum Institute (API), “Guide to

Groundwater Standards of the United States, ” 1983.

Henderson, T. R., J. Traubman, and T. Gallagher,

Groundwater: Strategies for State Action (Washington, DC: Environmental Law Institute, 1984).

Magnuson, P., “Groundwater Classification, ” September 1981 (copyright by Geraghty & Miller, Inc.,

Syosset, NY, 1982).

Miller, D., Geraghty & Miller, Inc., testimony before

the Subcommittee on Environment, Energy and Natural Resources, Committee on Government Operations, U.S. House of Representatives, Apr. 11-12,

1984.

Pye, V. A., R. Patrick, and J. Quarles, Groundwater

Contamination in the United States (Philadelphia:

University of Pennsylvania Press, 1983).
Index
Index

Community Water Supply Survey (CWSS), 40

correction of ground water contamination, 177-193

selecting a strategy, 177

corrective action alternatives, 178

perforrnance of corrective action alternatives, 183

technical and non-technical conditions determining

the applicability of corrective action alternatives,

179

stage of development of corrective action alternatives,

192

Federal efforts to correct groundwatcr contamination,

197-201

Federal Government experience, 200

statutory and regulatory provisions for sources of

contamination, 197

summary of Federal corrective action provisions, 198

Federal efforts to detect groundwater contamination,

145-161

groundwater monitoring and sources, 155

Federal programs, 156

monitoring and remedial action programs, 160

investigate ions of aquifer systems and ambient

groundwater quality, 146

ambient groundwater appraisal, 147

Regional Aquifer System Analysis Program, 147

U.S. Geological Survey, 145-146

Federal programs, 145

Federal-State Cooperative Program, 146

monitoring drinking water supplies, 147-150

EPA drinking water surveys, 149

public water systems, 147

source inventories, 150-154

formal studies, 150

hazardous waste sites, 151

open dumps, 150

surface impoundments, 152

regulatory requirements related to inventories, 153

reporting requirements, 152

EPA regulations: CWA and CERCLA, 152

D0T regulations: HLPSA and HMTA, 153

Federal efforts to prevent groundwater contamination, 215

aquifer protection, 225

prevention by sources, 215

performance requirements, 223

types of programs and sources addressed, 223

regulating the production and use of potential

contaminant, 226

Federal Insecticide, Fungicide, and Rodenticide Act,

228

Toxic Substances Control Act (TSCA), 226

Federal institutional framework to protect groundwater,

63-86

efforts to improve capabilities, 83-86

Federal research and development, 84

financial assistance, 83

technical assistance, 84

mechanisms for interagency coordination, 81

program-related agreements, 82

USGS coordinating committees, 82

water data coordination, 83

relevance of Federal statutes, 64

sources addressed by Federal statutes, 75-79

types of programs, 77

summary of Federal statutes and programs, 64-75

Federal legislation passed prior to the 1970s, 64

groundwater-related activities of Federal agencies, 72

water quality standards, 80-81

findings, 5-14

Federal and State approach to groundwater approach, 6

corrective act ion programs, 8

detection programs, 8

prevention programs, 8

national policy implications, 11-14

funding, 11

research and development, 13

technical assistance, 12

technical and nontechnical constraints, 9-10

groundwater contamination and its impacts, 19-58

concentration and frequency of substances in

groundwater, 38-43

governmental standards, 41

frequency of occurance of substances, 40

substances, 38

extent and nature of, 20-23

nationwide assessment, 20

substances detected in groundwater, 22

factors influencing a source’s potential to contaminate,

47-54

geographic location: pervasiveness and regionality, 49

number of sources and amounts of material flowing

through or stored in sources, 51

release characteristics, 47

health impacts, 23-36

adverse impacts of chemicals, 32

biological substances, 34

general issues, 23

interactions among multiple chemicals, 34

potential toxicity or potency of chemicals, 33

radioactive substances, 35

substances known to occur in groundwater, 24-31

non-health impacts, 36-38

economic impacts, 36, 39

environmental and social impacts, 37-38

potential for sources to contribute substances to

groundwater, 55

identifying sources, 55

modeling, 55

types of sources and associated substances, 43-46

association of substances with sources, 44

undetected substances, 43

Ground Water Supply Survey (GWSS), 40

243
244 ● Protecting the Nation’s Groundwater From Contamination

hydrogeologic investigations, 111-138

approaches for minimizing difficulties, 135-138

ensuring reliability, 135

conduct, 112-135

design of, 115

costs and detection limits, 130

monitoring networks, 134

techniques for obtaining information, 118

general approach, 112

objectives, 113

site conditions. 112

l(~isla(ion:

Atomic Energ)’ Act, 6.j, 66, 73, 78, 155, 156

Clean Water Act (CWA), 11, 20, 65, 66, 73, 78, 80,

83, 99, 100, 146, [52, 156, 161

Coastal Zone Manage]nent Act, 65, 66, 75, 78, 156

~;onlprchensi~’e Envirc nmcntal Response,

Corn pcrrsat ion, ami Liability Act (C ERCLA), 8,

6.5, 67, 74> 79, 10IJ, 151, 152, 1.53, 156, 160, 184,

197

F’tderal Insecticide Ful~gicide and Rodenticide Act

(FIFRA), 9, 65, 6’), 75, 156, 228

F’eder-al Land Policy and Management Act, 65, 67, 75,

156, 215

Hazardous Liquid Pipl:line Safety Act (HLPSA), 65,

68, 74, 77, 152, 153, 156

H:izardous .Nlatcrials ‘I’ransportation Act (HMTA), 65,

68, 74, 152, 153, 156

National k~n~ironment:d Policy Act, 65, 68, 73, 79, 156

Rc’clarnation Act, 65, 08, 73, 79, 156

Resource Conservation and Recovery Act (RCRA), 8,

11, 65, 69, 74, 78, 83, 100, 150, 155, 156, 160,

197, 200

Ri\rcrs and Harbor Ac of 1899, 73

Safe’ Drinking Water P,ct (SDWA), 7, 8, 20, 65, 69,

74, 78, 80, 83, 10( , 147, 149, 150, 152, 153, 157

S(lrface Mining Contr(ll and Reclamation Act

(SMCRA), 11, 65, 70, 74, 78, 79, 83, 158, 215

‘1’oxic Substances Control Act (TSCA), 9, 65, 70, 75,

i55, 158, 215, 226

Uranium Mill Tailings Radiation Control Act

(U,MTRCA), 8, 65, 70, 74, 78, 79, 100, 158, 160,

197, 200, 201, 215

Water- Pollution Control Act of 1948

\$’ater Research and Development Act, 65, 70, 75, 79,

158

National Interim Primar} Drinking Water Regulations

(NIPDWR), 80

National Organics Monitoring Survey (NOMS), 40

N:itional Organics Reconnaissance Survey (NORS), 40

National Science Foundation, 72

National Scrcwning Program for Organics in Drinking

W’ater (NSP), 41

Nuclear Rc>Sulator?’ Corn mission, 72

State efforts to correct grxmndwater contamination,

205-210

State efforts to detect groundwater contamination,

165-171

detection programs for sources of contamination, 165

formal procedures for monitoring, 168

inventory and monitoring activities, 166

use, preferences and problems with techniques for

hydrogeologic investigations, 169

OTA survey, 170

State institutional framework to protect groundwater from

contamination, 89-107

OTA State survey, 89, 96, 97, 99

State activities, 92, 93

agency reorganization, 98

coordination programs, 95

facility development, 97

public education, 97

special studies, 95

staff development and training, 95

State perceptions about problems, 91

State perspective on Federal programs, 98-103

responses about selected Federal laws, 98

State use of Federal guidance on quality standards

State strengths and problems in programs to deal with

contamination and desired Federal assistance,

103-107

correction, 106

detection, 106

improving capabilities, 105

prevention, 106

sources, 104

standards, 105

State prevention approaches, 235

aquifer protection, 239

impact reduction, 239

source programs, 237

U.S. Army Corps of Engineers, 82

U.S. Coast Guard, 152

b’. S. Department of Agriculture, 72, 82

Soil Conservation Service (SCS), 161

U.S. Department of Commerce, 72, 82

U.S. Department of Defense, 72, 201

U.S. Department of Energy, 72, 73

U.S. Department of Housing and Urban Development,

72

U.S. Department of the Interior, 72, 82

Bureau of Land Management (BLM), 75, 82

U. S. Department of Transportation, 152, 153

U.S. Environmental Protection Agency, 6, 20, 72, 73, 82,

147, 149, 150, 151, 152, 153, 154, 161, 229

National Inorganic and Radionuclides Survey (NIRS),

40

U.S. Food and Drug Administration, 84

U.S. General Accounting Office (GAO), 150, 159

U.S. Geological Survey, 12, 84, 95, 145, 146, 161

volatile organic chemicals (VOCS), 40, 41

World Health Organization (WHO), 35