**Response Protocol Toolbox:**

Planning for and Responding to

Drinking Water Contamination Threats and Incidents

**Module 6: Remediation and Recovery Guide**

Interim Final -- April 2004

![](media/image1.wmf)

**OTHER RESPONSE PROTOCOL TOOLBOX MODULES**

> **Module 1: Water Utility Planning Guide** *(December 2003)*
>
> Module 1 provides a brief discussion of the nature of the
> contamination threat to the public water supply. The module also
> describes the planning activities that a utility may undertake to
> prepare for responding to contamination threats and incidents.
>
> **Module 2: Contamination Threat Management Guide** *(December 2003)*
>
> Module 2 presents the overarching framework for management of
> contamination threats to the drinking water supply. The threat
> management process involves two parallel and interrelated
> activities: 1) evaluating the threat, and 2) making decisions
> regarding appropriate actions to take in response to the threat.
>
> **Module 3: Site Characterization and Sampling Guide** *(December
> 2003)*
>
> Module 3 describes the site characterization process in which
> information is gathered from the site of a suspected contamination
> incident at a drinking water system. Site characterization activities
> include the site investigation, field safety screening, rapid field
> testing of the water, and sample collection.
>
> **Module 4: Analytical Guide** *(December 2003)*
>
> Module 4 presents an approach to the analysis of samples collected
> from the site of a suspected contamination incident. The purpose of
> the Analytical Guide is **not** to provide a detailed protocol.
> Rather, it describes a framework for developing an approach for the
> analysis of water samples that may contain an unknown contaminant. The
> framework is flexible and will allow the approach to be crafted based
> on the requirements of the specific situation. The framework is also
> designed to promote the effective and defensible performance of
> laboratory analysis.
>
> **Module 5: Public Health Response Guide** *(April 2004)*
>
> Module 5 deals with the public health response measures that would
> potentially be used to minimize public exposure to potentially
> contaminated water. It discusses the important issue of who is
> responsible for making the decision to initiate public health response
> actions, and considers the role of the water utility in this decision
> process. Specifically, it examines the role of the utility during a
> public health response action, as well as the interaction among the
> utility, the drinking water primacy agency, the public health
> community, and other parties with a public health mission.
>
> **Module 6: Remediation and Recovery Guide** *(April 2004)*
>
> Module 6 describes the planning and implementation of remediation and
> recovery activities that would be necessary following a confirmed
> contamination incident. The remediation process involves: system
> characterization; selection of remedy options; provision of an
> alternate drinking water supply during remediation; and monitoring to
> demonstrate that the system has been remediated. Module 6 describes
> the types of organizations that would likely be involved in this stage
> of a response, and the utility's role during remediation and recovery.

**ACKNOWLEDGEMENTS**

This document was prepared by the United States Environmental Protection
Agency, Office of Ground Water and Drinking Water, Water Security
Division through a contract with SAIC. The EPA Work Assignment Manager
was Brain Frazer, and the SAIC Work Assignment Manager was Mary Wolfe.
The primary contributors to the document included:

-   Steven C. Allgeier (US EPA, OGWDW)

-   Patrick E. Ransom (SAIC)

-   Robert B. Stewart (SAIC)

Other contributors included Susan Dolgin, Grace Robiou, and Veronika
Pesinova of the US EPA, OGWDW.

Additional support for this work was provided by a panel of peer
reviewers, including: Erica Brown (AMWA), Cliff Bowen (California DHS),
Keith Burkhart (ATSDR), Stephen Clark (US EPA, OGWDW), Kim Fox (US EPA,
ORD), Alan Hais (US EPA, ORD), David Hartman (Cincinnati Water Works),
Ron Hunsinger (EBMUD), Eileen Leininger (Newport News Water Works),
Carrie Lewis (Milwaukee Water Works), Matthew Magnuson (US EPA, ORD),
Nelson Mix (US EPA OSWER), Debbie Newberry (US EPA, OGWDW), Amit
Pramanik (WERF), Alan Roberson (AWWA), Stanley States (Pittsburgh Water
and Sewer Authority), Gene Taylor (US EPA, Region 10), Caroline Wehling
(US EPA, OGC), Gregory Welter (O'Brien & Gere Engineers), James Wheeler
(US EPA, OWM), and Kelvin Yamada (California DHS).

TABLE OF CONTENTS

[1 Introduction and Overview 17](#introduction-and-overview)

[1.1 Objectives 17](#objectives)

[1.2 Process Overview 17](#process-overview)

[1.3 Organization 21](#organization)

[2 Planning 23](#planning)

[2.1 Elements of Planning 23](#elements-of-planning)

[2.2 Roles and Responsibilities 27](#roles-and-responsibilities)

[2.3 Documentation 30](#documentation)

[3.1 Risk Assessment 33](#risk-assessment)

[3.1.1 Rapid Risk Assessment 34](#rapid-risk-assessment)

[3.1.2 Integrating the System Characterization/Feasibility Study with
Risk Assessment
34](#integrating-the-system-characterizationfeasibility-study-with-risk-assessment)

[3.1.3 Establishing Preliminary Remediation Goals (PRGs)
34](#establishing-preliminary-remediation-goals-prgs)

[3.1.4 Establishing Final Remediation Goals
35](#establishing-final-remediation-goals)

[3.2 System Characterization 35](#system-characterization)

[3.2.2 Implementing System Characterization
40](#implementing-system-characterization)

[3.3 Feasibility Study 42](#feasibility-study)

[3.3.1 Establishing Remedial Action Objectives
42](#establishing-remedial-action-objectives)

[3.3.2 Development and Screening of Remedial Alternatives
43](#development-and-screening-of-remedial-alternatives)

[3.3.3 Treatability Studies 44](#treatability-studies)

[3.3.4 System Characterization/Feasibility Study (SC/FS) Report
45](#system-characterizationfeasibility-study-scfs-report)

[4 Analysis of Alternatives and Remedy Selection
46](#analysis-of-alternatives-and-remedy-selection)

[4.1 Analysis of Alternatives 46](#analysis-of-alternatives)

[4.1.1 No Additional Action Alternative
47](#no-additional-action-alternative)

[4.1.2 Alternatives for the Treatment of Contaminated Water
47](#alternatives-for-the-treatment-of-contaminated-water)

[4.1.3 Alternatives for the Rehabilitation of System Components
60](#alternatives-for-the-rehabilitation-of-system-components)

[4.1.4 Alternatives for Affected Environmental Media
63](#alternatives-for-affected-environmental-media)

[4.1.5 Additional Resources 63](#additional-resources)

[4.2 Remedy Evaluation Criteria 64](#remedy-evaluation-criteria)

[4.3 Comparative Analysis of Alternatives and Remedy Selection
65](#comparative-analysis-of-alternatives-and-remedy-selection)

[5 Remedial Design, Remedial Action, and Post-Remediation Monitoring and
Operations
67](#remedial-design-remedial-action-and-post-remediation-monitoring-and-operations)

[5.1 Remedial Design 67](#remedial-design)

[5.2 Remedial Action 68](#remedial-action)

[5.3 Disposal of Remediation Residuals
69](#disposal-of-remediation-residuals)

[5.3.1 Applicable Regulations 69](#applicable-regulations)

[5.3.2 Types of Waste and Management Options
72](#types-of-waste-and-management-options)

[5.4 Post-Remediation Monitoring 76](#post-remediation-monitoring)

[5.5 Return to Normal Operations 76](#return-to-normal-operations)

[6 Long-Term Alternate Domestic Water Supply
78](#long-term-alternate-domestic-water-supply)

[6.1 Determining Supply Needed to Meet System Demands
79](#determining-supply-needed-to-meet-system-demands)

[6.1.1 Estimating Normal Demand 80](#estimating-normal-demand)

[6.1.2 Restricting Demand Through Conservation
81](#restricting-demand-through-conservation)

[6.2 Identifying Long-Term Alternate Water Supplies
81](#identifying-long-term-alternate-water-supplies)

[6.2.1 Options for Alternate Water Supplies
82](#options-for-alternate-water-supplies)

[6.2.2 Who Provides the Alternate Water Supply?
82](#who-provides-the-alternate-water-supply)

[6.2.3 Selection of Alternate Water Supplies
82](#selection-of-alternate-water-supplies)

[6.2.4 Public Awareness 83](#public-awareness)

[6.3 Implementation of Long-Term Water Supply
84](#implementation-of-long-term-water-supply)

[6.3.1 Connection to Existing Municipal or Private Supplies
84](#connection-to-existing-municipal-or-private-supplies)

[6.3.2 Connection to New Water Source
84](#connection-to-new-water-source)

[6.3.3 Temporary Treatment and Distribution Systems
85](#temporary-treatment-and-distribution-systems)

[7 Public Communication 86](#public-communication)

[7.1 Agencies Involved in Communication
86](#agencies-involved-in-communication)

[7.1.1 Department of Homeland Security
86](#department-of-homeland-security)

[7.1.2 Water Utility and/or Drinking Water Primacy Agency
87](#water-utility-andor-drinking-water-primacy-agency)

[7.2 Forms of Communication 87](#forms-of-communication)

[7.2.1 Public Meetings 88](#public-meetings)

[7.2.2 Public Presentations 89](#public-presentations)

[7.2.3 Public Workshops 89](#public-workshops)

[7.2.4 Public Information Repository 90](#public-information-repository)

[7.2.5 Revised Public Notifications 90](#revised-public-notifications)

[7.3 Types of Information to be Communicated
91](#types-of-information-to-be-communicated)

[7.3.1 Alternate Water Supplies 91](#alternate-water-supplies)

[7.3.2 Remediation and Recovery Activities
91](#remediation-and-recovery-activities)

[7.3.3 Water System Return to Normal Operations
92](#water-system-return-to-normal-operations)

[7.3.4 Continued Sampling and Analysis
92](#continued-sampling-and-analysis)

[8 References and Resources 93](#references-and-resources)

[9 Appendices 99](#appendices)

[9.1 Suggested Format for System Characterization/Feasibility Study Work
Plan
99](#suggested-format-for-system-characterizationfeasibility-study-work-plan)

[9.2 Elements for a Quality Assurance Project Plan
100](#elements-for-a-quality-assurance-project-plan)

[9.3 Elements of a Health and Safety Plan
101](#elements-of-a-health-and-safety-plan)

[9.4 Suggested Format for System Characterization/Feasibility Study
Report
102](#suggested-format-for-system-characterizationfeasibility-study-report)

[9.5 Hypothetical Example of a Contamination Threat to a Drinking Water
System: Threat Warning Through Remediation and Recovery
103](#hypothetical-example-of-a-contamination-threat-to-a-drinking-water-system-threat-warning-through-remediation-and-recovery)

**LIST OF TABLES**

[**TABLE 6-1. DOCUMENTATION OF PLANNING, IMPLEMENTATION, AND ASSESSMENT
ACTIVITIES FOR WATER SYSTEM REMEDIATION AND RECOVERY**
31](#__RefHeading___Toc69893188)

[**TABLE 6-2. SUMMARY OF POTENTIALLY APPLICABLE WATER TREATMENT
TECHNOLOGIES** 48](#__RefHeading___Toc69893189)

[TABLE 6-3. RELATIONSHIP BETWEEN LONG-TERM RESTRICTION AND NEED FOR
LONG-TERM ALTERNATE WATER SUPPLY 78](#__RefHeading___Toc69893190)

**List of Figures**

[**FIGURE 6‑1. OVERVIEW OF THE REMEDIATION AND RECOVERY PROCESS**
20](#__RefHeading___Toc70487195)

[**FIGURE 6-2. INCIDENT COMMAND STRUCTURE FOR REMEDIATION AND RECOVERY
ACTIVITIES** 27](#__RefHeading___Toc70487196)

[**FIGURE 6-3. PROCESS FOR EVALUATING THE NEED FOR A TREATABILITY
STUDY** 45](#__RefHeading___Toc70487197)

[FIGURE 6-4. CONCEPTUAL FRAMEWORK FOR IMPLEMENTING A LONG-TERM ALTERNATE
WATER SUPPLY 80](#__RefHeading___Toc70487198)

**DISCLAIMER**

The mention of trade names or commercial products does not constitute
endorsement or recommendation for use.

NOTE REGARDING CONSISTENCY WITH OTHER RESPONSE PLANNING EFFORTS

This module includes references to the Federal Response Plan (FRP) and
the United States Government Interagency Domestic Terrorism Concept of
Operations Plan (CONPLAN). At this time, the Department of Homeland
Security is developing a National Response Plan (NRP), which will
supercede the FRP and CONPLAN (US Department of Homeland Security,
2004). The final NRP is scheduled to be published in July 2004. After
publication of the final NRP, EPA plans to update this module and other
modules of the Response Protocol Toolbox to be consistent with the NRP.

**NOTE REGARDING REGULATORY AND STATUTORY CITATIONS**

This module summarizes and contains references to specific sections of
the Code of Federal Regulations (CFR) and to specific Statutes that
codify the Nation's environmental laws (e.g., the Clean Water Act). The
summaries contained herein do not substitute for these requirements.
Interested persons should become familiar with the regulations and
Statutes themselves. CFR sections can be accessed at
<http://www.gpoaccess.gov/ecfr/>. Additional information on specific
environmental laws, along with links to the full statutory text, can be
found at <http://www.epa.gov/epahome/laws.htm>. The full text of the
*Public Health Security and Bioterrorism Preparedness and Response Act
of 2002* (PL 107-188, June 12, 2002), or Bioterrorism Act, may be found
at
<http://frwebgate.access.gpo.gov/cgi-bin/getdoc.cgi?dbname=107_cong_public_laws&docid=f:publ188.107.pdf>.

**ACRONYMS**

  --------- -------------------------------------------------------------
  AA        Activated alumina

  AMSA      Association of Metropolitan Sewerage Agencies

  ATSDR     Agency for Toxic Substances and Disease Registry

  AWWA      American Water Works Association

  CDC       Centers for Disease Control and Prevention

  CERCLA    Comprehensive Environmental Response, Compensation, and
            Liability Act

  CFR       Code of Federal Regulations

  CWA       Clean Water Act

  CSM       Conceptual site model

  DHS       Department of Homeland Security

  DOJ       Department of Justice

  EPCRA     Emergency Planning Community Right-to-Know Act

  ERP       Emergency response plan

  ESF       Emergency support function

  FBI       Federal Bureau of Investigation

  FEMA      Federal Emergency Management Agency

  FRP       Federal Response Plan

  FSP       Field sampling plan

  GAC       Granular activated carbon

  GIS       Geographic information system

  HASP      Health and safety plan

  HHS       Department of Health and Human Services

  HSPD      Homeland Security Presidential Directive

  ICS       Incident Command System

  JIC       Joint Information Center

  LDR       Land Disposal Restrictions

  MCL       Maximum contaminant level

  NCP       National Oil and Hazardous Substances Pollution Contingency
            Plan

  NF        Nanofiltration

  NPDES     National Pollutant Discharge Elimination System

  O&M       Operation and maintenance

  OSHA      Occupational Safety and Health Administration

  PAC       Powdered activated carbon

  PDD       Presidential Decision Directive

  POTW      Publicly owned treatment works

  PRG       Preliminary remediation goal

  QA        Quality assurance

  QC        Quality control

  QAPP      Quality assurance project plan

  RCRA      Resource Conservation and Recovery Act

  RO        Reverse Osmosis

  SAP       Sampling and analysis plan

  SC/FS     System characterization/Feasibility study

  SDWA      Safe Drinking Water Act

  TCLP      Toxicity characteristic leaching procedure

  TSCA      Toxic Substances Control Act

  USACE     United States Army Corps of Engineers

  US EPA    United States Environmental Protection Agency

  UV        Ultraviolet

  WCIT      Water Contaminant Information Tool

  WUERM     Water Utility Emergency Response Manager
  --------- -------------------------------------------------------------

**GLOSSARY**

Definitions in this glossary are specific to the Response Protocol Tool
Box but have been conformed to common usage as much as possible.

**Agency** -- a division of government with a specific function, or a
non-governmental organization (e.g., private contractor, business, etc.)
that offers a particular kind of assistance. In the *incident command
system* (ICS), agencies are defined as jurisdictional (having statutory
responsibility for *incident* mitigation) or assisting and/or
cooperating (providing resources and/or assistance).

**Analytical Approach** -- a plan describing the specific analyses that
are performed on the samples collected in the event of a *water
contamination* *threat*. The analytical approach is based on the
specific information available about a contamination *threat*.

**Analytically Confirmed** -- in the context of the *analytical
approach*, a *contaminant* is considered analytically confirmed if it
has undergone analytical confirmation as defined in Modules 3 and 4.

**Chemical Speciation** -- chemical speciation refers to the specific
chemical form (or species) of a *contaminant* in a given matrix. For
example, arsenic in water can exist as part of different molecules, each
with its own chemical, physical, and toxicological properties.

**'Confirmed'** -- in the context of the *threat evaluation* process, a
*water contamination incident* is 'confirmed' if the information
collected over the course of the *threat evaluation* provides definitive
evidence that the water has been contaminated.

**Conceptual Site Model (CSM)** -- a basic description of how
contaminants enter a system, their fate and transport within the system,
and routes of exposure to organisms and humans.

**Consequence** -- the adverse outcome resulting from a drinking *water
contamination incident*. In the context of the *threat management*
process, the consequence considers both the number of individuals
potentially affected as well as the severity of the health effect
experienced upon exposure.

**Consequence Management** -- The Department of Homeland Security (DHS)
defines consequence management as measures to protect *public health*
and safety, restore essential government services, and provide
*emergency* relief to governments, businesses, and individuals affected
by the *consequences* of terrorism (FEMA, 2003,
<http://www.fema.gov/pdf/rrr/frp/frp2003.pdf>).

﻿

**Contaminant** -- any chemical, biological, or radiological substance
that has an adverse effect on public health or the environment.

**Contingency Plan** -- targets a specific issue or event that arises
during disaster operations and presents alternative actions to respond
to the situation (FEMA, 2003,
<http://www.fema.gov/pdf/rrr/frp/frp2003.pdf>).

**'Credible'** -- in the context of the *threat evaluation* process, a
*water contamination threat* is characterized as 'credible' if
information collected during the *threat evaluation* process
corroborates information from the *threat warning*.

**Crisis Management** -- the Federal Bureau of Investigation (FBI)
defines crisis management as measures to identify, acquire, and plan the
use of resources needed to anticipate, prevent, and/or resolve a
*threat* or act of terrorism (FEMA, 2003,
<http://www.fema.gov/pdf/rrr/frp/frp2003.pdf>).

**Drinking Water Primacy Agency** -- the *agency* that has primary
enforcement responsibility for national drinking water regulations,
namely the Safe Drinking Water Act as amended. Drinking water primacy
for a particular State or tribe may reside in one of a variety of
agencies, such as health departments, environmental quality departments,
etc. or may be US EPA. The drinking water primacy agency may also play
the role of *technical assistance provider* to drinking water utilities.

**Emergency** -- as defined in the *Stafford Act*, an emergency is any
occasion or instance for which, in the determination of the President,
Federal assistance is needed to supplement State and local efforts and
capabilities to save lives and to protect property, *public health*, and
safety, and includes emergencies other than natural disasters (FEMA,
2003, <http://www.fema.gov/pdf/rrr/frp/frp2003.pdf>).

**Emergency Operations Center** -- a pre-designated facility established
by an *agency* or jurisdiction to coordinate overall *agency* or
jurisdictional response and support to an *emergency*.

**Emergency Response Plan (ERP)** -- a document that describes the
actions that a drinking water utility would take in response to various
emergencies, disasters, and other unexpected *incidents*.

**Feasibility Study** -- the mechanism for the development, screening,
and evaluation of alternative *remedial actions*. The feasibility study
is conducted concurrently with the *system characterization*. This
terminology is adopted from the US EPA's Superfund program (US EPA,
2004a, <http://www.epa.gov/superfund/whatissf/sfproces/rifs.htm>).

**Immediate Operational Response** -- an action taken in response to a
'possible' contamination *threat* in an attempt to minimize the
potential for exposure to the suspect water. Immediate operational
response actions will generally have a negligible *impact* on consumers.

**Impact** -- the *consequence* or effect on drinking water consumers,
or the utility itself, resulting from the implementation of response
actions. An impact could also be considered as the cost of implementing
a response action.

**Incident** -- a *confirmed* occurrence that requires response actions
to prevent or minimize loss of life or damage to property and/or natural
resources. A drinking *water contamination* *incident* occurs when the
presence of a harmful *contaminant* has been *confirmed*.

**Incident Command System (ICS)** -- a standardized on-scene *emergency*
management concept specifically designed to allow its user(s) to adopt
an integrated organizational structure equal to the complexity and
demands of single or multiple *incidents*, without being hindered by
jurisdictional boundaries.

**Incident Commander** -- the individual responsible for the management
of all *incident* operations. If the State or local government is the
*lead agency*, then the incident commander will come from the State or
local organization that has primary responsibility for managing the
situation. For responses under the National Response System, the
pre-designated *On-Scene Coordinator* generally assumes the role of
incident commander.

**Investigation Site** -- the location where *site characterization*
activities are performed. If a suspected contamination site has been
identified, it will likely be designated as a primary investigation
site. Additional or secondary investigation sites may also be identified
due to the potential spread of a *contaminant*.

**Joint Information Center (JIC)** -- a center established to coordinate
the Federal public information activities on-scene. It is the central
point of contact for all news media at the scene of the *incident*.
Public information officials from all participating Federal agencies
should collocate at the JIC. Public information officials from
participating State and local agencies also may collocate at the JIC
(FEMA, 2003, <http://www.fema.gov/pdf/rrr/frp/frp2003.pdf>).

**Lead Agency** -- as defined in Homeland Security Presidential
Directive-7 (HSPD-7), the Federal department or agency assigned lead
responsibility to manage and coordinate a specific function --- either
crisis management or consequence management. Lead agencies are
designated on the basis that they have the most authorities, resources,
capabilities, or expertise relative to accomplishment of the specific
function.

**Lead Federal Agency** -- the *agency* designated by the President to
lead and coordinate the overall Federal response. The lead federal
agency is determined by the type of emergency. In general, a lead
federal agency establishes operational structures and procedures to
assemble and work with *agencies* providing direct support. Functions of
the lead federal agency include providing an initial assessment of the
situation; developing an action plan; monitoring and updating
operational priorities; and ensuring each *agency* exercises its
concurrent and distinct authorities under U.S. law. Specific
responsibilities of a lead federal agency vary according to the
*agency*'s unique statutory authorities.

**Mutual Aid Agreement** -- a written agreement between *agencies*
and/or jurisdictions in which they agree to assist one another upon
request by furnishing personnel, equipment, or water.

**National Oil and Hazardous Substances Pollution Contingency Plan
(NCP)** -- also called the National Contingency Plan, the NCP (40 CFR
300) administers the response powers and capabilities authorized by the
Comprehensive Environmental Response, Compensation, and Liability Act
(CERCLA) and Section 311 of the Clean Water Act (CWA). The NCP applies
to all Federal agencies and provides for efficient, coordinated, and
effective response to discharges of oil and releases of hazardous
substances, pollutants, and *contaminants* (FEMA, 2003,
<http://www.fema.gov/pdf/rrr/frp/frp2003.pdf>).

**On-Scene Coordinator** -- the Federal official predesignated to
coordinate and direct hazardous substance removal actions. Depending on
the location of the *incident*, the On-Scene Coordinator may be provided
either by EPA, United States Coast Guard, the Department of Defense, or
the Department of Energy. On-Scene Coordinators from the Department of
Defense or Department of Energy will be used to coordinate and direct
actions at their respective *agency* facilities (FEMA, 2003,
<http://www.fema.gov/pdf/rrr/frp/frp2003.pdf>).

**'Possible' Stage** -- the first stage of the *threat management*
process from the point at which the *threat warning* is received through
the determination as to whether or not the *threat* is 'possible.'

**Presidential Decision Directive (PDD)-39** -- establishes policy to
reduce the Nation's vulnerability to terrorism, deter and respond to
terrorism, and strengthen capabilities to detect, prevent, defeat, and
manage the *consequences* of terrorist use of weapons of mass
destruction. PDD-39 states that the United States will have the ability
to respond rapidly and decisively to terrorism directed against
Americans wherever it occurs, arrest or defeat the perpetrators using
all appropriate instruments against the sponsoring organizations and
governments, and provide recovery relief to victims, as permitted by law
(FEMA, 2003, <http://www.fema.gov/pdf/rrr/frp/frp2003.pdf>). The
responsibilities and objectives of PDD-39 have been updated through
HSPD-5.

**Preliminary Remediation Goal (PRG)** -- an acceptable *contaminant*
concentration for the *remedial action* to achieve. These concentration
levels are selected based on available criteria (e.g., Maximum
Contaminant Levels \[MCLs\]) or derived using risk-based criteria for
*systemic toxicants* and carcinogens.

**Public Health** -- the health and well being of an entire population
or community. Public health is not limited to the health of individuals.

**Quality Assurance (QA)** -- an integrated system of management
activities involving planning, implementation, documentation,
assessment, reporting, and quality improvement to ensure that a process,
item, or service is of the type and quality needed and expected by the
client (US EPA, 2001a,
<http://www.epa.gov/quality/qs-docs/r5-final.pdf>).

**Quality Control (QC)** -- the overall system of technical activities
that measures the attributes and performance of a process, item, or
service against defined standards to verify that they meet the stated
requirements established by the customer; operational techniques and
activities that are used to fulfill requirements for quality (US EPA,
2001a, <http://www.epa.gov/quality/qs-docs/r5-final.pdf>).

**Quality Assurance Project Plan (QAPP)** -- defined by US EPA as a
written document that describes the *quality assurance* procedures,
*quality control* specifications, and other technical activities that
should be implemented to ensure that the results of the project or task
to be performed will meet project specifications (US EPA, 2002g,
<http://www.epa.gov/quality/faq6.html>).

**Remedial Action** -- the actual construction or implementation phase
of the remediation and recovery process. This phase follows *remedial
design*. This terminology is adapted from that used in US EPA's
Superfund program (US EPA, 2004b,
<http://www.epa.gov/OCEPAterms/rterms.html>).

**Remedial Design --** a phase of the remediation and recovery process
that follows the *system characterization*/*feasibility study* (SC/FS)
and includes development of engineering drawings and specifications for
remediation of a contaminated *water system*. This terminology is
adapted from that used in US EPA's Superfund program (US EPA, 2004b,
<http://www.epa.gov/OCEPAterms/rterms.html>).

**Remedial Investigation** -- under US EPA's Superfund program, a
remedial investigation is an in-depth study designed to gather data
needed to determine the nature and extent of contamination at a
Superfund site; establish site cleanup criteria; identify preliminary
alternatives for *remedial action*; and support technical and cost
analyses of alternatives. The remedial investigation is usually done
with the *feasibility study*. Together they are usually referred to as
the "RI/FS" (US EPA, 2004b,
<http://www.epa.gov/OCEPAterms/rterms.html>).

**Remedial Process** -- the full sequence of actions taken to implement
a *remedial response*. The remedial process includes planning, *risk
assessment*, *system characterization*, *feasibility study*, analysis of
alternatives, *remedy* selection, *remedial design*, *remedial action*,
and post-remedial monitoring and operations.

**Remedial Project Manager** -- the EPA or state official responsible
for overseeing on-site *remedial action* (US EPA, 2004b,
<http://www.epa.gov/OCEPAterms/rterms.html>).

**Remedial Response** -- a long-term action that stops or substantially
reduces a release or potential release of *contaminants* that is serious
but not an immediate threat to *public health*. This terminology is
adapted from that used in EPA's Superfund program (US EPA, 2004b,
<http://www.epa.gov/OCEPAterms/rterms.html>).

**Remedy** -- see *Remedial Response*.

**Response Guidelines** -- a manual designed for use **during** the
response to a *water contamination threat*. Response Guidelines should
be easy to use and contain forms, flow charts, and simple instructions
to support staff in the field or decision officials in the *Emergency
Operations Center* during management of a crisis.

**Risk Assessment** -- qualitative and quantitative evaluation of the
risk posed to human health and/or the environment by the actual or
potential presence and/or use of specific pollutants (US EPA, 2004b,
<http://www.epa.gov/OCEPAterms/rterms.html>).

**Site Characterization** -- the process of collecting information from
an *investigation site* in order to support the evaluation of a drinking
water contamination threat. Site characterization activities include the
site investigation, *field safety screening*, *rapid field testing* of
the water, and sample collection. Site characterization is discussed in
Module 3.

**Stafford Act** -- the Robert T. Stafford Disaster Relief and Emergency
Assistance Act (Stafford Act) establishes the programs and processes for
the Federal government to provide disaster and emergency assistance to
States, local governments, tribal nations, individuals and qualified
private non-profit organizations. The provisions of the Stafford Act
cover all hazards including natural disasters and terrorist events.
Under the Stafford Act, a State Governor may request the President to
declare a major disaster or an emergency if an event is beyond the
combined response capabilities of the State and affected local
governments.

**Support Agency** -- any *agency* that provides technical support to
the *lead agency*, or takes on specific tasks delegated by the *lead
agency*, during the remediation and recovery process. Support agencies
may include the water utility, the *drinking water primacy agency*, the
Department of Health and Human Services (HHS), US EPA, and the United
States Army Corps of Engineers (USACE).

**System Characterization** -- a detailed assessment of the nature and
extent of contamination in a drinking *water system* for the purpose of
planning remediation of the contaminated *water system*. The system
characterization process is modeled, in part, on the concept of a
*remedial investigation* under US EPA's Superfund program and,
similarly, would be done with the *feasibility study*.

**System Characterization/Feasibility Study (SC/FS)** -- the combined
process of a *system characterization* and *feasibility study*, both of
which may be documented in one place in an SC/FS report.

**Systemic Toxicant** -- a toxin which affects the entire body or many
organs, rather than targeting specific organs or tissues (US National
Library of Medicine, 2001,
[http://www.sis.nlm.nih.gov/ToxTutor/Tox1/a12.htm](http://www.sis.nlm.nih.gov/Tox/ToxTutor.html)).

**Technical Assistance Provider** -- any organization or individual that
provides assistance to drinking water utilities in meeting their mission
to provide an adequate and safe supply of water to their customers. The
*drinking water primacy agency* may serve as a technical assistance
provider.

**Threat** -- an indication that a harmful *incident*, such as
contamination of the drinking water supply, may have occurred. The
threat may be direct, such as a verbal or written threat, or
circumstantial, such as a security breach or unusual water quality.

**Threat Evaluation** -- part of the *threat management* process in
which all available and relevant information about the *threat* is
evaluated to determine if the *threat* is '*possible'* or *'credible'*,
or if a contamination *incident* has been '*confirmed*.' This is an
iterative process in which the threat evaluation is revised as
additional information becomes available. The conclusions from the
threat evaluation are considered when making response decisions.

**Threat Management** -- the process of evaluating a contamination
*threat* and making decisions about appropriate response actions. The
threat management process includes the parallel activities of the
*threat evaluation* and making *response decisions*. The threat
management process is considered in three stages: '*possible*,'
'*credible*,' and '*confirmatory*.' The severity of the *threat* and the
magnitude of the response decisions escalate as a *threat* progresses
through these stages.

**Treatability Study** -- a lab study, pilot study, or full-scale study
used to determine a technology's effectiveness and/or cost for treating
the contaminated water, system components, or other media. Treatability
studies are used for new or unproven technologies or where there are
gaps in knowledge about the technology's effectiveness or cost.

**Triad Approach** -- defined by US EPA as an integration of systematic
planning, dynamic work plans, and real-time measurement technologies to
achieve more cost-effective remedial strategies (US EPA, 2004c,
<http://www.epa.gov/tio/triad>).

**Water System** -- the water supply source, treatment plant
infrastructure and processes, and the water distribution system.

**Water Contamination Incident** -- a situation in which a *contaminant*
has been successfully introduced into the system. A water contamination
incident may or may not be preceded by a *water contamination threat*.

**Water Contamination Threat** -- a situation in which the introduction
of a *contaminant* into the *water system* is threatened, claimed, or
suggested by evidence. Compare water contamination threat with *water
contamination incident.* Note that threatening a *water system* may be a
crime under the Safe Drinking Water Act as amended by the Public Health
Security and Bioterrorism Preparedness and Response Act of 2002.

**Water Utility Emergency Response Manager (WUERM)** -- the
individual(s) within the drinking water utility management structure
that has the responsibility and authority for managing certain aspects
of the utility's response to an *emergency* (e.g., a contamination
*threat*) particularly during the initial stages of the response. The
responsibilities and authority of the WUERM are defined by utility
management, and will likely vary based on the circumstances of a
specific utility.

# Introduction and Overview

## Objectives

This module provides guidance on the remediation and recovery process
that should be used when a drinking *water contamination incident* has
been *confirmed*. The target audience for this module includes people
who will be involved in *system characterization*, *risk assessment*,
and *remedial response* activities following a confirmed contamination
*incident* (see Section 2.2 of this module). Such people will likely
include *water utility emergency response managers* (WUERMs), utility
staff, state drinking water program managers, public health officials,
*technical assistance providers*, hazardous materials responders or
specialized remediation teams (i.e., from the US EPA), other federal
agencies involved in the remediation process, and law enforcement
agencies. The target audience also includes *lead agency* personnel and
decision-makers who will determine the need for long-term alternate
water supplies, select remedial technologies, determine when to return
to normal operations, and interface or communicate with the public.

This module is intended to be a planning tool. Individuals responsible
for evaluating remediation and communication strategies should review
and understand this module in its entirety and integrate the concepts
presented into their own *response guidelines*. The role of water
utilities will vary depending on the nature and complexity of the
remedial action and the resources of the utility. However, even if
*agencies* external to the utility assume primary responsibility for
coordinating the response, the role of the water utility and its staff
during the remediation and recovery process is critically important.
Accordingly, in reviewing this module, utility WUERMs and staff are
encouraged to identify and anticipate activities specific to their
*water system* in which they could participate -- or be asked to
participate -- during a remediation and recovery event.

## Process Overview

This section provides an overview of the remediation and recovery
process and summarizes the various documents that may be used to support
remediation and recovery activities. This overview is intended to
familiarize the reader with the entire process so that in subsequent
sections, details of the steps can be understood in the context of the
overall framework.

The need to initiate a remediation and recovery process will be
determined when a contamination incident is confirmed. Immediate
operational and public health response actions (Module 5) will precede
remediation and recovery activities, and will likely continue during
these activities.

Once contamination is confirmed, remediation and recovery must follow.
The goal of remediation and recovery is to return the water supply
system to service as quickly as possible while protecting *public
health* and minimizing disruption to normal life (or business
continuity). During the remediation and recovery stage of the *threat
management* process, the immediate urgency of the situation has passed,
and the magnitude of the remedial action requires careful planning and
implementation. While rapid recovery of the system is crucial, it is
equally important to follow a systematic process that establishes
remedial goals acceptable to all stakeholders, implements the *remedial
process* in an effective and responsible manner, and demonstrates that
the *remedial action* was successful. This module describes the elements
of such a systematic process.

The remediation and recovery process is designed to address extensive
contamination at concentrations that pose immediate and/or long-term
risks to human health and the environment. The process is applicable to
remediation of source water, treatment plant infrastructure, and/or
water distribution systems. The process is described as a sequence of
steps that should be implemented as quickly as possible to restore the
drinking water resource. A flow chart depicts the remediation and
recovery process (Figure 6-1), and key steps are summarized below.

-   **Ensure Long-Term Alternate Water Supply** -- While remediation is
    being carried out, a long-term alternate supply of domestic water
    (potable water) may be needed. A long-term alternative domestic
    water supply may differ from the short-term water supply described
    in Module 5. The need for a long-term alternative supply will depend
    on the nature and severity of the contamination event, the status of
    the water supply and the water distribution system, and the length
    of time needed to complete the remedial response and return the
    system to normal operation.

-   **Conduct System Characterization/Feasibility Study (SC/FS)** -- The
    SC/FS provides a detailed assessment of the nature and extent of
    contamination and screens for candidate treatment options.

-   **Conduct Risk Assessment** -- Risk assessment activities are used
    in tandem with the SC/FS to help establish *preliminary remediation
    goals* (PRGs), inform data collection activities, and select an
    appropriate *remedy*. []{.mark}

-   **Conduct Detailed Analysis of Alternatives** -- Candidate cleanup
    approaches and alternatives are evaluated and compared with
    remediation goals and other criteria, such as protectiveness and
    ease of implementation, to help choose the best remediation
    approach.

-   **Select Remedy**-- The preferred remedy is identified based on the
    Alternatives Analysis and the proven effectiveness of remediation
    technology for the specific contaminant.

-   **Prepare Remedial Design** -- Plans and specifications for applying
    selected remedies are prepared

-   **Undertake Remedial Action** -- Implementation and completion of
    cleanup activities include both treatment of the contaminated water
    and rehabilitation of system components. Following implementation of
    the remedy, it should be confirmed that the response actions have
    restored the drinking water system, before the system can return to
    normal operation.

-   **Conduct Post-Remediation Monitoring and Operations**
    **Assessment** - After site remediation actions are complete,
    monitoring of the system should be done to ensure that all actions
    are effective and operating as planned.

-   **Provide Public Communication** -- During remedial activities and
    before the water system is returned to normal operations, the water
    utility should communicate with and provide outreach to the
    community to restore public confidence in the water system and the
    quality of the water.

The sections of this module provide basic guidance on how to implement
the remediation and recovery process. The approach is modeled in part
after the Superfund hazardous substance response protocol given in the
*National Oil and Hazardous Substances Pollution Contingency Plan* at 40
CFR Part 300, Subpart E. This plan, also known as the National
Contingency Plan or NCP, describes the Superfund remedial response
program under the Comprehensive Environmental Response, Compensation,
and Liability Act (CERCLA). While a contaminated water system would
probably not be legally classified as a Superfund site, the Superfund
model is used for the following reasons:

-   At the remedial stage of the response to a contamination incident,
    the immediate public health threat will have been addressed through
    appropriate response actions, as discussed in Module 5. To implement
    a final remedy, it will be important to follow a systematic process
    involving careful planning.

-   Remediation professionals, who will likely be involved in the
    response action, are already familiar with existing hazardous
    substance response protocols.

-   When US EPA is involved in response to a contamination incident, the
    Federal Response Plan (FRP) requires the Agency to use the NCP
    structure.

-   Most states have programs for cleanup of sites contaminated by
    hazardous substances and many of these programs use processes
    similar to the federal Superfund process. While a contaminated water
    system likely would not fall under these programs, states might
    choose to adopt "Superfund-like" processes when they are responsible
    for remediation, because of their familiarity with these processes.

The degree to which remediation and recovery follows the model presented
here will depend on the nature and extent of contamination. A
small-scale incident might not involve all of the steps presented in
Figure 6-1. For example, if the contamination is contained through
immediate operational response and is confined to a well-defined area,
extensive *system characterization* might not be necessary. The initial
site characterization (see Module 3) could provide sufficient
information to guide the process, eliminating the need to go through the
more involved system characterization process. If treatment options for
the contaminant of concern are known and well defined, then the
feasibility study and analysis of alternatives could be combined.

Even when all steps are necessary, the streamlined model presented here
describes a remediation and recovery process that is reduced in scale,
scope, and duration from the Superfund process. Only in the most severe
and extensive contamination incidents would the remediation and recovery
process be expected to require a period of time approaching that of a
typical Superfund remediation. Appendix 9.5 presents a hypothetical
example of a contamination threat to a drinking water system, including
remediation and recovery based on the model presented here. In the
example, the remediation and recovery process is completed within a
short time frame (90 days), even though most of the steps shown in
Figure 6-1 are included.

[]{#__RefHeading___Toc70487195 .anchor}![](media/image1.wmf)Figure 6‑1.
Overview of the Remediation and Recovery Process

## Organization

This module is organized into nine sections as described below. Planners
and response action personnel are encouraged to review this module in
its entirety, as well as the other modules in the *Response Protocol
Toolbox,* to obtain a comprehensive understanding of the remedial
response approach for dealing with *water contamination threats*.

> Section 1: [Introduction and Overview]{.underline}: discusses the
> purpose of this module, provides an overview of the remediation and
> recovery process, and describes the overall organization of the
> module. The overview is intended to acquaint the reader with the
> entire process so that details described in subsequent sections can be
> understood in the context of the overall process.
>
> Section 2: [Planning]{.underline}: discusses planning for remediation
> of a drinking water system after an intentional contamination
> incident. Planning involves developing a framework for ensuring that
> the right type, quantity, and quality of information are obtained to
> support remedial decisions. This section also discusses roles and
> responsibilities during the remedial process and summarizes the types
> of documentation that may be produced during the process.
>
> Section 3: [Risk Assessment, System Characterization, and Feasibility
> Study]{.underline}: discusses the SC/FS and integration of risk
> assessment into the remedial process. This section also discusses the
> use of *treatability studies* when an unproven remediation technology
> is being considered.
>
> Section 4: [Analysis of Alternatives and Remedy
> Selection]{.underline}: describes a flexible sequence of steps
> designed to select the appropriate remedial response to address
> contaminated drinking water and contaminated water system components
> (e.g., storage tanks, filters, pipes, pumps, etc.). These steps
> include a detailed analysis of candidate technologies and remedial
> options, followed by remedy selection.
>
> Section 5: [Remedial Design, Remedial Action, and Post-Remediation
> Monitoring and Operations]{.underline}: discusses *remedial design*,
> implementation/completion of the selected remedy, and operation and
> maintenance (O&M) of the remediation system. This section describes
> contaminant residuals that could be generated during remedial action
> and the regulations that should be considered when managing the
> residuals as waste. Guidance is presented on determining attainment of
> the remediation goal(s) through post-remediation monitoring. Special
> considerations for return to normal operations are discussed.
>
> Section 6: [Long-Term Alternative Domestic Water Supply]{.underline}:
> describes criteria for determining if a long-term alternate water
> supply is necessary and describes contingency planning, public
> communication, and long-term consideration where a "do not drink" or
> "do not use" determination has been made.
>
> Section 7: [Public Communication]{.underline}: presents guidance on
> maintaining effective public communication during the remedial process
> and return to normal operations.
>
> Section 8: [References and Resources]{.underline}: lists the
> references used in the development of this module and additional
> information resources.
>
> Section 9: [Appendices]{.underline}: provides additional information
> and materials that may help in preparing for remediation and recovery
> of a contaminated water system.

# Planning

## Elements of Planning

Systematic planning is a common sense approach designed to ensure that
preparation and response activities are known in advance of an incident,
so that if an incident occurs, the response can be swift, thorough and
effective. The degree of planning required depends upon the type and
complexity of potential contamination incidents, the human health and
environmental risks, and the resources available to deal with the
incident.

Systematic planning can be used to ensure that decision makers have
accurate, sufficient, and timely information to support later decision
making involving system characterization, remediation, and recovery. The
level of planning detail that is required will depend on how important
the information is, and how it is going to be used. **The outputs of
systematic planning are required as inputs to the various planning
documents (see Section 2.3 and Table 6-1) used throughout the
remediation and recovery process.**

Systematic planning is important for successfully executing water system
characterization and remediation activities that rely on rapid data
collection and decision-making. US EPA's Quality System web site
includes documents on systematic planning (US EPA, 2004i,
<http://www.epa.gov/quality/>). Other similar planning processes may be
appropriate based on the requirements and responsibilities of the lead
agency and the laboratories used to support the remedial process.

Much of the information needed to plan for water system remediation and
recovery should have been developed and included in the water utility's
*Emergency Response Plan* (ERP). The ERP is developed or revised in
response to the requirements of the *Public Health Security and
Bioterrorism Preparedness and Response Act of 2002* (PL 107-188, June
12, 2002). Information that should be included in the ERP includes:
identification of planning partners, system-specific information (e.g.,
system maps and drawings), alternative water sources, chain-of-command,
and communication processes. Guidance on ERPs may be found in *Large
Water System Emergency Response Plan Outline: Guidance to Assist
Community Water Systems in Complying with the Public Health Security and
Bioterrorism Preparedness and Response Act of 2002* (US EPA, 2003e,
<http://www.epa.gov/safewater/security/pdfs/erp-long-outline.pdf>).
Another resource is *Emergency Response Plan Guidance for Small and
Medium Community Water Systems to Comply with the Public Health Security
and Bioterrorism Preparedness and Response Act of 2002* (US EPA, 2004l,
http://www.epa.gov/safewater/security/pdfs/guide_small_medium_erp.pdf).

Key elements of a systematic planning process include:

-   **Identifying and involving the decision makers and support
    personnel** -- As described in Section 2.2 of this module, State and
    local governments will have initial and primary authority for
    *consequence management* in the event of a terrorist attack against
    a drinking water facility or infrastructure. If Federal assistance
    is provided under the authorities of the *Stafford Act*, then lead
    agencies and associated personnel will be established as specified
    in the FRP (FEMA, 2003,
    <http://www.fema.gov/pdf/rrr/frp/frp2003.pdf>).

-   **Identifying the schedule and resources** -- The lead agency will
    work in partnership with *support agencies* to establish schedules
    and milestones. Funding guidelines are given in the FRP (FEMA, 2003,
    <http://www.fema.gov/pdf/rrr/frp/frp2003.pdf>), Terrorism Incident
    Annex, Section VI ("Funding Guidelines").

-   **Describing the goal(s) and objective(s)** -- The goal of
    remediation and recovery is to return the system to service as
    quickly as possible -- providing safe, reliable drinking water --
    while protecting public health and minimizing disruption to normal
    life (or business continuity). However, for a complex site or a high
    concentration contamination incident, it may be necessary to
    establish intermediate/tiered goals such as first treating the water
    for non-drinking use (e.g., for sanitation and fire protection),
    followed by a secondary goal of treating the water for consumption.
    Goals should be specified in both qualitative terms (e.g.,
    restoration of fire protection and basic sanitation) and in
    quantitative terms (e.g., concentration-based remediation goals for
    the water, system components, and affected environmental media).

-   **Developing a *Conceptual Site Model* (CSM)** -- A key step in the
    planning process is developing a CSM. A CSM is used to organize
    information that is already known about a site and to identify data
    gaps. A CSM is a basic description of how contaminants enter a
    system, their fate and transport within the system, the locations
    where exposure to the contaminant(s) is likely to occur, and the
    exposure routes of concern (e.g., dermal, ingestion, or inhalation).
    The CSM provides an essential framework for assessing risks from
    contaminants, developing remedial strategies, determining source
    control needs, and deciding how to address unacceptable risks. The
    guidance provided in Module 5, Section 3, for assessing the public
    health consequences of a drinking water contamination incident may
    also be useful for developing a CSM.

> Once the contamination event is confirmed, but before implementing a
> final remedial response, the investigation/cleanup team should
> assemble existing information into the CSM. An initial CSM can be
> developed as soon as the contamination threat is confirmed (e.g.,
> hours to days). The CSM should be refined throughout the remedial
> process as new information is obtained. The CSM will likely be
> developed by an inter-organizational team, under the direction of the
> lead agency. The CSM team may include representatives from the primacy
> agency/health department, the drinking water utility, site remediation
> specialists, and technical assistance providers.
>
> Specific information to be collected for the CSM includes:

-   Configuration of the water supply system (e.g., physical location of
    pipes in the distribution system). An up-to-date hydraulic model of
    the water system, if one is available, will be valuable, although
    maps may be the best source of information for many systems.

-   The properties of contaminants confirmed or suspected in water
    (e.g., density, solubility, vapor pressure, Henry's Law Constant,
    etc.). One source for information on chemical properties is US EPA's
    Water Contaminant Information Tool (WCIT). The WCIT is currently
    under development (see Module 2, Appendix 8.9 for more information).
    Other sources of contaminant information that might be used in the
    interim include: <http://www.bt.cdc.gov/agent/agentlistchem.asp>
    (CDC, 2003); and
    [http://www.atsdr.cdc.gov/](http://www.cdc.gov/atsdr/index.html)
    (CDC, 2004). Module 5, Section 3.1 includes a comprehensive
    discussion of contaminant properties related to public health
    response, risk assessment and the development of the CSM.

-   Point(s) and times of contaminant introduction into the system
    (source characterization). Note that contamination could be
    introduced at any point within the system, including source water
    (e.g., stream, river, spring, reservoir, impoundment, or aquifer
    (wells)), treatment plant, storage systems, and/or the distribution
    system (e.g., transmission mains, service connections, storage
    tanks, etc.).

-   Points and pathways of exposure as well as potentially exposed
    populations.

-   Risks, with the primary focus on human health and the secondary
    focus on ecological or economic *consequences*.

> The CSM is documented in the system characterization documents (see
> Sections 3.2.1 and 3.3.4 of this module) by written descriptions of
> site conditions and supported by maps, cross sections, engineering
> drawings, analytical data, site diagrams, and modeling results that
> illustrate location, concentrations, and direction and rate of
> movement of the contamination. Much of the information that would
> support the development of a CSM should be readily available from the
> facility's existing ERP and from information generated as part of the
> initial site characterization (Module 3).

The characterization/cleanup team uses the CSM as an input to the system
characterization, sampling plan development, and risk assessment
activities. The CSM serves several purposes -- as a planning instrument;
as a modeling and data interpretation tool; and as a means of
communication among members of a project team, decision makers,
stakeholders, and field personnel. For more information on CSMs
including an example, see pages 2-7 and 2-8 of *Guidance for Conducting
Remedial Investigations and Feasibility Studies under CERCLA, Interim
Final* (US EPA, 1988a,
<http://www.epa.gov/superfund/action/guidance/remedy/rifs/overview.htm>).

-   **Identifying the type of data needed** -- It will be necessary to
    identify the kinds of information needed, the sources of
    information, and confirm that appropriate sampling and analysis
    methods exist. For example, information may be needed on the
    physical properties of the affected media, flow rates, chemical
    and/or biological characteristics, and inputs necessary for models
    and risk assessments. An assessment should be made regarding the
    extent to which existing data can be used to support
    decision-making.

-   **Identifying constraints on data collection** -- Limitations that
    could affect data collection should be evaluated. Examples of
    limitations include resource or time constraints, practical
    constraints such as physical access to sampling locations,
    environmental conditions (e.g., weather), and availability of
    equipment and personnel.

-   **Determining the data quality needed** -- For each type of data to
    be collected, the data quality, meaning the performance and
    acceptance criteria for useable data, should be specified and
    clearly documented. The acceptable level of uncertainty in the data
    should be specified.

-   **Determining the quantity of data needed** -- The quantity of data
    refers to the total number of samples and/or measurements that will
    be necessary. For practical reasons and to expedite field activities
    under emergency conditions, the number of samples obtained during
    the initial phases of the system characterization may be based on
    judgment of the characterization team. However, the number of
    samples needed for the detailed system characterization and
    demonstration that remediation goals have been achieved may be based
    on statistical sampling design. For more information on sampling
    designs, consult *Guidance for Choosing a Sampling Design for
    Environmental Data Collection* (US EPA, 2002f,
    <http://www.epa.gov/quality>).

-   Describing how, when, and where the data will be obtained, and
    defining the boundary of the study -- Outputs of the various
    planning steps are used as inputs to develop sampling plans to
    support each stage of the system characterization and remediation
    process. Sampling plans may be necessary at various stages including
    initial site characterization (see Module 3), system
    characterization to support remedial response, and post-remediation
    to confirm attainment of remediation goals.

-   Specifying quality assurance and quality control activities to
    assess the quality performance criteria -- *Quality assurance* (QA)
    and *quality control* (QC) activities should be specified in a
    *Quality Assurance Project Plan* (QAPP) or similar document and
    implemented to ensure that data collection activities are conducted
    correctly and can be assessed against performance criteria. For
    example, QA/QC activities could include the preparation and analysis
    of field and laboratory control samples, chain-of-custody
    procedures, and technical system performance audits and evaluations.
    Using a "graded" approach, the QAPP and related planning documents
    need only contain information necessary to address the work to be
    performed, thus facilitating more rapid development of plans and
    implementation of field activities.

-   Identifying and selecting analytical laboratories -- Planning
    documents should identify those laboratories that have the
    capability to analyze the samples and meet the performance criteria
    established in the planning process, given the specific contaminants
    confirmed or suspected. In the case of complex or exotic
    contaminants, there may be a limited number of laboratories
    available to provide analysis within the necessary response time.
    Module 4 provides an extensive discussion on the nature and
    capabilities of laboratory infrastructure in the U.S. and may be of
    use in identifying appropriate laboratories. Another source is US
    EPA's Compendium of Environmental Testing Laboratories
    ([**http://www.epa.gov/compendium**](http://www.epa.gov/compendium)).

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-   **Planning for data quality assessment --** Project-specific plans
    should describe methods for data analysis, evaluation, and
    assessment against the intended use of the data and quality
    acceptance/performance criteria.

## Roles and Responsibilities

The remediation and recovery process is implemented when a contamination
incident has been confirmed. For a confirmed incident, an agency
external to the water utility may assume the responsibility for
coordinating the response under an *Incident Command System* (ICS).
Figure 6-2 depicts an example of unified command under ICS that might be
assembled during the remediation and recovery phase (see also Module 1,
Section 4.4). Note that while Figure 6-2 shows a hierarchical
organizational structure, significant coordination and communication is
necessary among the various levels of the ICS.

![](media/image1.wmf)

[]{#__RefHeading___Toc70487196 .anchor}Figure 6-2. Incident Command
Structure for Remediation and Recovery Activities

Whether the local, State, or Federal government will exercise primary
authority will depend on the kind and size of the incident and resource
needs for remediation and recovery. State and local governments have
primary responsibility for consequence management, including remediation
and recovery activities. State and local emergency operations plans
generally establish direction and control procedures for their agencies
using an ICS. In many States, State law or local jurisdiction ordinances
will identify, by organizational position, the person(s) that will be
responsible for serving as the *incident commander*. In most cases, the
incident commander will come from the State or local organization that
has primary responsibility for managing the emergency situation.

State assistance may be provided to local governments in responding to a
terrorist threat or recovering from the consequences of a terrorist
incident, as in any natural or man-made disaster. The governor, by State
law, is the chief executive officer of the State or commonwealth and has
full authority to discharge the duties of his or her office and to
exercise all powers associated with the operational control of the
State's emergency services during a declared emergency (FEMA, 2001,
<http://www.fema.gov/pdf/rrr/conplan/conplan.pdf>). State agencies are
responsible for ensuring that essential services and resources are
available to the local authorities and Incident Commander when
requested.

If the magnitude of the remediation and recovery efforts exceeds the
capabilities and resources of the local and State governments, or when
Federal interests are involved, then the Federal Government will provide
assistance under the FRP, when activated under the Stafford Act (FEMA,
2003, <http://www.fema.gov/pdf/rrr/frp/frp2003.pdf>). The FRP provides
the mechanism for federal departments and agencies to coordinate
delivery of Federal assistance and resources to augment efforts of State
and local governments overwhelmed by a major disaster or *emergency*,
including a terrorist act. Nongovernmental organizations such as the
American Red Cross can also be mobilized under the FRP. When the FRP is
activated, a single federal agency will serve as the overall *lead
federal agency*, coordinating the efforts of other agencies, including
lead agencies with responsibility for managing and coordinating a
specific function and support agencies who provide technical support or
take on specific tasks. Additional information on the FRP is given in
Module 1, Appendix 6.2, including how the FRP is activated and under
what circumstances.

Roles and responsibilities for key local, state, and federal departments
and agencies in supporting water system remediation and recovery are
summarized below.

**Water Utility** -- The water utility will possess the most detailed
first-hand knowledge and technical expertise regarding the configuration
and operation of the water source, storage, treatment, and distribution
systems. Accordingly, the WUERM, Water Utility Emergency Operations
Center Manager, and other water utility personnel may serve as technical
advisors within the ICS and provide support to lead agency personnel
responsible for characterization, remediation, and recovery of a
contaminated water system. If Federal assistance is provided under the
authorities of the Stafford Act (42 U.S.C. §5121, et seq.), then
responsibility for specific tasks most likely will be delegated to the
water utility by the Department of Homeland Security (DHS)/Federal
Emergency Management Agency (FEMA) or US EPA (who will support long-term
site restoration and environmental cleanup). The FRP outlines how the
Federal Government implements the Stafford Act.

**Pre-planning is perhaps the most important remediation planning
activity that a water utility can do.** The water utility should play a
key role in planning for a remedial response to contamination, including
evaluating containment options and ensuring rapid access to the site, as
well as providing operating records, engineering drawings, etc. that may
be needed by response action personnel. This type of planning differs
from that depicted in Figure 6-1 and Section 2 of this module because it
is done not only during remediation, but also in anticipation of
potential future remediation activities.

**State and Local Authorities** -- State and local authorities maintain
initial responsibility for managing domestic incidents. The Federal
Government will assist State and local authorities when their resources
are overwhelmed or when Federal interests are involved. In those cases,
the local or state agencies (e.g., local health department) should work
in partnership with the lead federal agency.

**Federal Government:** Key areas of responsibility for Federal
government agencies that would potentially support water system
remediation and recovery efforts are highlighted below:

-   **Department of Justice (DOJ)/Federal Bureau of Investigation
    (FBI)** -- The DOJ is the lead federal agency for threats or acts of
    terrorism within U.S. territory. DOJ assigns lead responsibility for
    *crisis management* to the FBI, which acts primarily in a law
    enforcement capacity. Crisis management refers to measures to
    identify, acquire, and plan the use of resources needed to apprehend
    and prosecute the perpetrators. In this role, the FBI operates as
    the on-scene manager for the Federal Government.

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-   **Department of Homeland Security (DHS)/Federal Emergency Management
    Agency (FEMA)** -- The DHS supports the overall lead federal agency
    by operating as the lead agency for *consequence management* until
    the overall lead federal agency role is transferred to DHS. FEMA, a
    branch of the DHS, supports the lead federal agency for "consequence
    management" throughout the Federal response or serves as the lead
    federal agency when the Attorney General transfers the role to DHS.
    Consequence management refers to measures to protect public health
    and safety, restore essential government services, and provide
    emergency relief to governments, businesses, and individuals
    affected by the consequences of terrorism.

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-   **Department of Health and Human Services (HHS)** - HHS will
    activate technical operations capabilities to support the Federal
    response to threats or acts of chemical, biological, and
    radiological terrorism. HHS may coordinate with individual agencies,
    such as Centers for Disease Control and Prevention (CDC). The CDC is
    authorized by the *HHS Health and Medical Services Support Plan for
    the Federal Response to Acts of Chemical/Biological Terrorism* to
    use the structure, relationships, and capabilities described in the
    HHS plan to support response operations.

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-   **US Environmental Protection Agency (US EPA)** -- US EPA will
    activate technical operations capabilities to support the Federal
    response to acts of chemical, biological, and radiological
    terrorism. US EPA may coordinate with individual agencies identified
    in the NCP[^1] to use the structure, relationships, and capabilities
    of the National Response System as described in the NCP \[40 CFR
    Part 300 subpart B\] to support response operations. If the NCP is
    implemented, then:

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-   The Hazardous Materials *On-Scene Coordinator* (in the case of
    immediate responses) or *Remedial Project Manager* (in the case of
    longer term remedial actions) under the NCP will coordinate the NCP
    response with the DHS official who is responsible for on-scene
    coordination of all Federal support to State and local governments;
    and

-   The NCP response may include risk assessment, consultation, agent
    identification, hazard detection and reduction, environmental
    monitoring, decontamination, and long-term site restoration
    (environmental cleanup) operations.

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-   **US Army Corps of Engineers (USACE)** - Under FRP Emergency Support
    Function (ESF) #3, Public Works and Engineering Annex, the USACE
    serves as the primary agency responsible, in part, for emergency
    restoration of critical public facilities. Activities can include
    the temporary restoration of water supplies and emergency
    contracting to support public health and safety, such as providing
    for potable water.

In summary, no single agency or organization at the Federal, State,
local, or private-sector level possesses the authority and expertise to
unilaterally implement remediation and recovery actions. If Federal
assistance is provided under the authority of the Stafford Act, then
responsibility for specific tasks will be delegated by the lead agency
to those entities that have the skills and resources to implement them.

## Documentation

The specific documentation and actions needed to conduct the remediation
and recovery of a contaminated water system will depend upon
site-specific circumstances and the requirements specified by the lead
agency. Table 6-1 describes the various documents that could be used to
support remediation and recovery activities. In many cases, lead
agencies such as DHS or US EPA, rather than the utility, will be
responsible for developing these planning documents or for delegating
that responsibility to a supporting agency. However, the utility will
have an important role in the planning and implementation of remedial
activities, and thus should have an understanding of the planning
process to better support the effort.

[]{#__RefHeading___Toc69893188 .anchor}Table 6-1. Documentation of
Planning, Implementation, and Assessment Activities for Water System
Remediation and Recovery

+-------------+---------------+----------------------------+---------+
| **Remedial  | **Supporting  | **Purpose**                | *       |
| Process     | Do            |                            | *Module |
| Activity**  | cumentation** |                            | 6       |
|             |               |                            | Se      |
|             |               |                            | ction** |
+=============+===============+============================+=========+
| System      | System        | Documents decisions made   | 3.2.1   |
| Charac      | Cha           | during the                 |         |
| terization/ | racterization | planning/scoping process   |         |
| Feasibility | Work Plan     | and presents anticipated   |         |
| Study       |               | future tasks that are part |         |
| (SC/FS)     |               | of system characterization |         |
|             |               | and the feasibility study. |         |
|             |               | Serves as a tool for       |         |
|             |               | assigning responsibilities |         |
|             |               | and setting schedule and   |         |
|             |               | costs.                     |         |
+-------------+---------------+----------------------------+---------+
|             | Sampling and  | The SAP consists of two    | 3.2.1   |
|             | Analysis Plan | parts: (1) QAPP that       |         |
|             | (SAP)         | describes the policy,      |         |
|             |               | organization, functional   |         |
|             | -   Quality   | activities, and quality    |         |
|             |     Assurance | assurance and quality      |         |
|             |     Project   | control protocols          |         |
|             |     Plan      | necessary to ensure data   |         |
|             |     (QAPP)    | collected will meet user   |         |
|             |               | needs; and (2) the FSP     |         |
|             | -   Field     | that provides guidance for |         |
|             |     Sampling  | all fieldwork by defining  |         |
|             |     Plan      | in detail the sampling and |         |
|             |     (FSP)     | data-gathering methods to  |         |
|             |               | be used.                   |         |
+-------------+---------------+----------------------------+---------+
|             | Health and    | Identifies personnel,      | 3.2.1   |
|             | Safety Plan   | training and medical       |         |
|             |               | monitoring requirements,   |         |
|             |               | equipment, site control    |         |
|             |               | measures, and other        |         |
|             |               | procedures to conform to   |         |
|             |               | performing organization\'s |         |
|             |               | health and safety program  |         |
|             |               | and applicable             |         |
|             |               | Occupational Safety and    |         |
|             |               | Health Administration      |         |
|             |               | (OSHA) requirements.       |         |
+-------------+---------------+----------------------------+---------+
|             | System        | Identifies preliminary     | 3.3.4   |
|             | Char          | remediation goals (PRGs)   |         |
|             | acterization/ | and presents outputs of    |         |
|             |               | screening of alternatives. |         |
|             | Feasibility   | Used as input to risk      |         |
|             | Study Report  | assessment and             |         |
|             |               | documentation of data      |         |
|             |               | collection and analysis in |         |
|             |               | support of the Remedy      |         |
|             |               | Selection Study.           |         |
+-------------+---------------+----------------------------+---------+
| T           | Treatability  | Specifies test objectives, | 3.3.3   |
| reatability | Study Work    | specialized equipment and  |         |
| Study       | Plan          | materials necessary,       |         |
|             |               | treatment test procedures, |         |
|             |               | parameters to measure,     |         |
|             |               | analytical methods, data   |         |
|             |               | management, data analysis  |         |
|             |               | and interpretation, health |         |
|             |               | and safety, and residuals  |         |
|             |               | management.                |         |
+-------------+---------------+----------------------------+---------+
|             | Treatability  | Describes testing          | 3.3.3   |
|             | Test          | performed, results of the  |         |
|             | Evaluation    | tests, and how the results |         |
|             | Report        | would affect the           |         |
|             |               | evaluation of the remedial |         |
|             |               | alternatives being         |         |
|             |               | considered. Describes      |         |
|             |               | effectiveness of the       |         |
|             |               | treatment technology and   |         |
|             |               | estimated costs for        |         |
|             |               | applying the technology    |         |
|             |               | for remediation.           |         |
+-------------+---------------+----------------------------+---------+
| System      | Remedy        | Presents a comparative     | 4.3     |
| Remediation | Selection     | analysis of remedial       |         |
|             | Report        | alternatives and describes |         |
|             |               | those actions that will    |         |
|             |               | satisfy the remedial       |         |
|             |               | action objectives.         |         |
+-------------+---------------+----------------------------+---------+
|             | Remedial      | Documents, specifications, | 5.1     |
|             | Design Work   | and drawings that detail   |         |
|             | Plan and      | the steps to be taken      |         |
|             | supporting    | during the remedial        |         |
|             | documentation | action. Other documents    |         |
|             |               | could include: Design      |         |
|             |               | Criteria Report, Basis of  |         |
|             |               | Design Report,             |         |
|             |               | Specifications, Drawings   |         |
|             |               | and Schematics,            |         |
|             |               | Construction Quality       |         |
|             |               | Assurance Plan, Draft      |         |
|             |               | Operation and Maintenance  |         |
|             |               | (O&M) Manual, Remedial     |         |
|             |               | Action Solicitation        |         |
|             |               | Package, Remedial Action   |         |
|             |               | Schedule, and Remedial     |         |
|             |               | Action Cost Estimate.      |         |
+-------------+---------------+----------------------------+---------+
|             | Remedial      | Describes all remedial     | 5.2     |
|             | Action Work   | response plans and actions |         |
|             | Plan and      | taken and the basis for    |         |
|             | Report(s)     | determining that the       |         |
|             |               | remediation goals were (or |         |
|             |               | were not) attained.        |         |
+-------------+---------------+----------------------------+---------+
|             | Post          | Describes sampling         | 5.4     |
|             | Remediation   | activities of remediated   |         |
|             | Monitoring    | area and critical use      |         |
|             | Plan          | areas to evaluate          |         |
|             |               | continued success of       |         |
|             |               | remedial action.           |         |
+-------------+---------------+----------------------------+---------+
| Long-Term   | Contingency   | Identifies possible        | 6       |
| Alternate   | Plan for      | sources of alternate water |         |
| Water       | Long-Term     | supply.                    |         |
| Supply      | Alternate     |                            |         |
|             | Water         |                            |         |
|             | Supply\*      |                            |         |
+-------------+---------------+----------------------------+---------+
| Community   | C             | Communicates revised       | 7       |
| Relations/  | ommunications | public notifications,      |         |
|             | Strategy      | water supply alternates,   | (See    |
| Co          |               | remediation and recovery   | also    |
| mmunication |               | options, estimated time to | Module  |
| Plan        |               | return to normal           | 5,      |
|             |               | operation, and information | Section |
|             |               | on continued monitoring    | 5)      |
|             |               | and analysis of the water  |         |
|             |               | system after remediation.  |         |
+-------------+---------------+----------------------------+---------+

\* A separate plan may not be necessary if identification of alternative
water supplies is addressed in the utility's *Emergency Response Plan*
as recommended in *Large Water System Emergency Response Plan Outline:
Guidance to Assist Community Water Systems in Complying with the Public
Health Security and Bioterrorism Preparedness and Response Act of 2002*
(US EPA, 2003e,
<http://www.epa.gov/safewater/security/pdfs/erp-long-outline.pdf>) and
*Emergency Response Plan Guidance for Small and Medium Community Water
Systems to Comply with the Public Health Security and Bioterrorism
Preparedness and Response Act of 2002* (US EPA, 2004l,
http://www.epa.gov/safewater/security/pdfs/guide_small_medium_erp.pdf)*.*

# Risk Assessment, System Characterization, and Feasibility Study

After a contamination incident has been confirmed, additional
information and data will be needed to support remediation and recovery
actions. This additional information and data will be obtained via a
System Characterization/Feasibility Study (SC/FS):

-   The *system characterization* serves as the mechanism for collecting
    data to more fully characterize system conditions, determine the
    nature and extent of the contamination, and assess risk to human
    health and the environment.

-   The *feasibility study* is the mechanism for the development,
    screening, and evaluation of candidate remedial technologies or
    actions. If necessary, it may include conducting treatability
    testing to evaluate the potential performance and cost of the
    treatment technologies that are being considered.

Risk assessment activities also will be conducted during the SC/FS
process to evaluate the reduction in risk resulting from the *immediate
operational response* actions, to aid in establishing risk-based
remediation levels, and to assess potential risk reductions from
implementation of a long-term remedy.

The various steps, or phases, of the SC/FS process are summarized in the
following sections. As shown in Figure 6-1, the system characterization
and feasibility study must be conducted together at the same time. The
reason for doing both together is that data collected for system
characterization also are needed for the risk assessment and for the
development of remedial alternatives in the feasibility study. The
outputs of system characterization in turn affect the data needs and
scope of treatability studies (if needed) and additional field
investigations (if needed).

The overall approach to system characterization through remediation is
similar to that used in the hazardous substance response protocol in the
NCP for a Superfund *remedial investigation* and feasibility study (see
US EPA, 1988a,
<http://www.epa.gov/superfund/action/guidance/remedy/rifs/overview.htm>).

## Risk Assessment

Upon confirmation of a contamination incident, the lead agency for
consequence management will quickly assess the risks posed to on-site
workers and the public. The lead agency typically will be DHS/FEMA or US
EPA in consultation with public health agencies such as the CDC. The
rapid risk assessment will help guide response actions. During the
remedial response phase, additional risk assessment may be necessary to
evaluate risk reduction resulting from the immediate operational
response actions, to help establish PRGs, and to assess potential risk
reductions from implementation of a long-term remedy. The relationship
between risk assessment activities and remedial response actions was
shown previously in Figure 6-1.

### Rapid Risk Assessment

US EPA is developing guidance and tools to help evaluate the risks
associated with drinking water from systems affected by a contamination
incident. The guidance is intended to help determine whether water
contamination exists at levels sufficient to warrant further action and
to evaluate the risks posed by the contaminants. Use of the Rapid Risk
Assessment tools may significantly reduce the time it takes to complete
the system characterization, remediation, and recovery. It will also
provide a consistent basis for evaluating risks if multiple sites are
involved. These tools are now being developed. When they become
available, information on accessing them will be found at:
<http://www.epa.gov/ordnhsrc> (US EPA, 2004h).

### Integrating the System Characterization/Feasibility Study with Risk Assessment

Data generated from the system characterization will be used as inputs
to risk assessment activities. The outputs of the risk assessments will
in turn be used to establish PRGs and to inform further field
investigations. The outputs of the feasibility study will be a list of
candidate technologies and remediation alternatives. Risk assessment
tools will be used to evaluate the protectiveness of the proposed
remedies.

Data generated during the SC/FS should therefore be usable for risk
assessment. This means that the characterization team should plan to
obtain data of sufficient type, quantity, and quality, collected at the
necessary times and locations, to support the system characterization,
feasibility study, and risk assessment efforts. This is discussed in
detail in later sections.

### Establishing Preliminary Remediation Goals (PRGs)

Early in the remediation and recovery process, it will be necessary to
establish long-term, media-specific target concentrations for use in
screening and selecting remedial alternatives. Ideally, these target
concentrations will be set at levels that result in acceptable risks to
human health and the environment. Early development of these goals
should help streamline the process of identifying candidate treatment
technologies. These initial concentration goals are known as Preliminary
Remediation Goals, or PRGs.

If the contaminant is known and an action level exists, then this action
level could serve as a PRG. Examples of action levels include Maximum
Contaminant Levels or MCLs for drinking water, or Effluent Limitations
Guidelines for treated water. The action level may be based on a
combination of factors including human health protection, technical
feasibility, and/or ecological effects.

If an action level does not exist, then one approach for establishing a
risk-based PRG is to perform risk calculations, in a manner similar to
that used by US EPA in the Superfund program (US EPA, 1991,
<http://www.epa.gov/superfund/programs/risk/ragsb/index.htm>). A
risk-based PRG can be derived using risk equations that reflect the
potential human health risk from exposure to a chemical, assuming
certain characteristics of exposure (e.g., exposure pathway, exposure
time and frequency, body weight, etc.). By setting the total risk for
carcinogenic effects at a target risk level (e.g., 10^-6^ or 1 in
1,000,000), it is possible to solve the risk equation for the
concentration term which is then used as the risk-based PRG. A similar
approach is used to set PRGs based on noncarcinogenic effects (e.g., by
setting the hazard index equal to 1).

### Establishing Final Remediation Goals

The final remediation goals will be established upon completion of the
SC/FS and identification of the remedial action objectives (see Section
3.3.1). Final remediation goals should be based on acceptable exposure
levels that are protective of human health and the environment. In the
absence of established drinking water standards (such as MCLs and
non-zero MCL Goals established under the Safe Drinking Water Act
\[SDWA\]), decision makers should consider other criteria[^2], such as
the following:

-   For *systemic toxicants*, acceptable exposure levels could be set at
    concentration levels at which there is no excessive risk of adverse
    health effects to the human population, including sensitive
    subgroups such as children, during a lifetime or part of a lifetime
    of exposure.

-   For known or suspected carcinogens, acceptable exposure levels are
    generally concentration levels that represent an excess upper limit
    of lifetime cancer risk to an individual of between 10^−4^ and
    10^−6^ (1 in 10,000 and 1 in 1,000,000, respectively) based on the
    relationship between dose and response.

-   Factors related to technical limitations, such as
    detection/quantification limits for contaminants.

-   Potential exposure routes. Ingestion of contaminated water is the
    most obvious exposure route; however, for certain contaminants, the
    public could be exposed to the contaminant through inhalation and
    dermal contact through showering and bathing with the contaminated
    water. Recommended final remedial goals based upon ingestion,
    inhalation, and dermal exposure to contaminated water can be
    established using methodologies similar to those used by US EPA in
    the Superfund program (US EPA, 1989,
    <http://www.epa.gov/superfund/programs/risk/ragsa/index.htm>; US
    EPA, 2002h,
    <http://www.epa.gov/superfund/programs/risk/ragse/index.htm>). A
    remedial goal that will reflect the aggregate risk via multiple
    exposure pathways can be calculated utilizing standard exposure
    assumptions, and incorporating oral and inhalation toxicity
    information from sources such as US EPA's Integrated Risk
    Information System (US EPA, undated a, <http://www.epa.gov/iris/>).

## System Characterization

The scope of the system characterization will generally be broader and
more detailed than the initial pre-remedial site characterization
(described in Module 3). The initial pre-remedial site characterization
gathers information to help determine whether or not the threat is
'credible.' In contrast, the system characterization focuses on the
nature, extent, and fate of particular contaminants in the water system
and its components to support the selection of appropriate response and
remediation actions. It is important to tailor the system
characterization to specific conditions and circumstances within the
system where contamination is likely to be found. It is equally
important to establish the boundaries of the contamination to help
define the extent of the remedial action.

### System Characterization Planning Documents

Planning is essential to successfully characterize the system and to
select an appropriate remedial response. The outputs of the systematic
planning process (Section 2 of this module) are used as inputs to the
planning documents. Several planning documents may be necessary to
support the system characterization. These plans include the following:

-   System Characterization Work Plan;

-   Sampling and Analysis Plan (SAP) comprising two parts: a Quality
    Assurance Project Plan (QAPP) and Field Sampling Plan (FSP); and

-   Health and Safety Plan (HASP).

The level of detail necessary for these documents will depend on the
amount and quality of information that results from the initial site
characterization phase (see Module 3). Naturally, all data and
information gathered to this point should inform the development of the
System Characterization Work Plan, SAP, and HASP (if needed). The lead
agency may also have requirements regarding the specific planning
documents necessary for system characterization.

[System Characterization Work Plan]{.underline}

The System Characterization Work Plan documents information collected
and decisions made during the systematic planning process, and describes
anticipated future tasks. It also serves as a valuable tool for
assigning responsibilities and setting the project\'s schedule and cost.

The primary users of the System Characterization Work Plan will be the
lead agency for consequence management (usually either DHS/FEMA or US
EPA at the federal level) and the project team that will execute the
work. Secondary users of the System Characterization Work Plan include
other groups or agencies serving in a technical advisory or review
capacity, such as the water utility and local government agencies.

The System Characterization Work Plan should include the following
elements:

-   **Introduction** -- A general explanation of the reasons for the
    system characterization study and the expected results or goals of
    the study process.

-   **System Description and Summary of Existing Data** -- A description
    of the configuration and physical setting of the system, a summary
    of the contamination event/history, and current situation and system
    condition.

-   **Initial Evaluation** -- The initial evaluation is based on the CSM
    and describes the source(s) or point(s) of contaminant introduction,
    boundaries of the affected area of the system, exposure pathways,
    and the preliminary assessment of consequences to human health, the
    environment, and system infrastructure.

-   **System Characterization Work Plan Rationale** -- Documents data
    needs for both the risk assessment and the treatment technology
    evaluation identified during the systematic planning process. The
    work plan rationale describes how the activities will satisfy data
    needs.

-   **System Characterization Tasks** -- Describes the tasks to be
    performed during the system characterization. This description
    incorporates characterization tasks identified in the SAP (see
    below) and the preliminary determination of tasks to be conducted
    after system characterization (e.g., risk assessment and modeling).

Appendix 9.1 provides a suggested format for the System Characterization
Work Plan. The specific content of a given work plan and the individual
tasks needed will depend on the specific situation and the drinking
water system. Detailed guidance for the development of a work plan can
be found in US EPA's *Guidance for Conducting Remedial Investigations
and Feasibility Studies Under CERCLA* (US EPA, 1988a,
<http://www.epa.gov/superfund/action/guidance/remedy/rifs/overview.htm>).

[Sampling and Analysis Plan (SAP)]{.underline}

The SAP consists of two parts: (1) a QAPP that describes the policy,
organization, functional activities, and QA and QC protocols necessary
to achieve data quality objectives dictated by the intended use of the
data; and (2) the FSP that provides detailed guidance for all fieldwork
by defining the sampling and data-gathering methods to be used.

**Quality Assurance Project Plan (QAPP)** -- The QAPP is a critical
planning document for data collection for system characterization
because it documents all project activities, including QA and QC
activities. In the context of the SAP, QA is a system of management
activities designed to ensure that collected data will be of the type
and quality needed to support system characterization and remediation.
QC is the overall system of technical activities that measures the
attributes and performance (quality characteristics) of a measurement
process against defined standards to verify that they meet the stated
requirements established by the data user.

As recommended in the *US EPA Guidance for Quality Assurance Project
Plans, EPA QA/G-5* (US EPA 2002a,
<http://www.epa.gov/quality/qs-docs/g5-final.pdf>), a QAPP is composed
of four sections of project-related information called "groups," which
are subdivided into specific detailed "elements." The groups and
elements are summarized in the following subsections. See Appendix 9.2
for an outline of the elements of a QAPP.

-   **Project Management** - This group of elements address project
    management, including the project history and objectives, roles and
    responsibilities of the participants, etc. These elements ensure
    that the project has a defined goal, that the participants
    understand the goal and the approach to be used, and that the
    planning outputs have been documented.

-   **Data Generation and Acquisition** - These group elements address
    all aspects of project design and implementation. Implementation of
    these elements ensures that appropriate methods for sampling (as
    documented in the FSP), measurement, analysis, data collection or
    generation, data handling, and QC activities are used and are
    properly documented.

-   **Assessment and Oversight** -- These group elements include
    activities for assessing the effectiveness of implementation of the
    project and associated QA and QC activities. The purpose of
    assessment is to ensure that the QAPP is implemented as prescribed.

-   **Data Validation and Usability** - The elements in this group
    address the QA activities that are conducted after the data
    collection or data generation phase of the project is completed.
    Implementation of these elements ensures that the data conform to
    criteria specified in the QAPP, thus achieving the project
    objectives.

The QAPP should provide sufficient detail to demonstrate that:

-   The technical and quality objectives of system characterization are
    identified and agreed upon;

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-   The intended measurements, data acquisition, or data generation
    methods are appropriate for achieving system characterization
    objectives;

-   Assessment procedures are sufficient for confirming that data of the
    type and quality needed and expected are obtained; and

-   Limitations on the use of the data can be identified and documented.

Most environmental data collection and analysis operations involve the
coordinated efforts of many individuals, including managers, engineers,
scientists, statisticians, and others. The QAPP should integrate the
contributions and needs of everyone involved in data generation and data
usage into a clear, concise format of what is to be accomplished, how it
will be done, and by whom. The QAPP should provide understandable
instructions to those who implement the QAPP, such as the field sampling
team, the analytical laboratory, and the data reviewers. The use of
national consensus standards and practices is encouraged.

**Field Sampling Plan (FSP) --** The FSP defines in detail the sampling
and data-gathering methods to be used in the system characterization
effort. The FSP is more detailed than the Site Characterization Plan
(described in Module 3,Section 4.1) used for initial water system
characterization following a suspected water contamination incident. The
FSP should include the following elements:

-   **System Description** -- This is a description of the water system
    and related information such as surrounding water sources,
    watersheds, and hydraulic flow patterns. Available schematics or
    maps detailing the water system will assist in subsequent sampling
    activity and identify probable transport pathways for contaminants.
    Similar system information is obtained when developing the CSM as
    described in Section 2 of this module. The system description also
    should include descriptions of specific data gaps and ways in which
    sampling is designed to fill those gaps. This discussion helps
    orient the sampling team in the field.

-   **Sampling Objectives** -- This section of the FSP should clearly
    and succinctly state the objectives and the intended uses of the
    sampling data.

-   **Sample Location and Frequency** -- This section of the FSP
    identifies the location and sampling frequency of each sample to be
    collected, organized by sampling matrix (i.e., media) and the
    constituents to be analyzed. While the primary sampling matrix will
    be water in most cases, there may also be a need to sample
    sediments, deposits in distribution system piping, the pipe itself,
    etc. A table may be used to clearly identify the number of samples
    to be collected along with the appropriate number of replicates,
    blanks, and other control samples. A water distribution system map
    should be included to show the locations of existing or proposed
    sample points.

-   **Sample Identification** -- A sample identification system should
    be established. The sample identification should include the sample
    identification number, time of collection, date, a description of
    the sample matrix (e.g., water, sludge, filter media), analysis
    needed, preservative used (if any), name of the sample collector,
    and the project name or code. (See the "Sample Documentation Form"
    in Module 3, Appendix 8.4, as an example format for recording this
    information).

-   **Sampling Equipment and Procedures** -- Sampling procedures should
    be clearly written and described in the FSP. Step-by-step
    instructions for each type of sampling activity are necessary to
    enable the field team to gather data that will meet the data quality
    objectives. A list should include the equipment to be used and the
    material composition (e.g., Teflon, stainless steel) of the
    equipment, along with decontamination procedures. A sample
    collection kit, as described in Module 3, Section 3.2.1, illustrates
    the types of materials and supplies useful in collecting water
    samples. Collection of samples of matrices other than water may
    require additional materials and supplies.

-   **Sample Handling and Analysis** -- A table should be included in
    the FSP that identifies sample analysis methods to be used, sample
    preservation methods, types of sampling jars, shipping requirements,
    and holding times. The plan also should address procedures for
    documentation of field activities, chain-of-custody, and sample
    handling within the laboratory. See the chain-of-custody form in
    Module 3, Appendix 8.5, for recording this information.

As with the QAPP, development of an FSP involves the coordinated efforts
and expertise of the individuals involved with field sampling,
laboratory analysis, and oversight of the system characterization. Just
as with the QAPP, the use of national consensus standards and practices
is encouraged.

[Health and Safety Plan (HASP)]{.underline}

OSHA helps set and implement national safety and health standards for
emergency responders. Foremost among these standards is the Hazardous
Waste Operations and Emergency Response standard (29 CFR 1910.120(q)).
Among other provisions, the standard requires entities engaged in
emergency response to provide appropriate training to their workers, to
use an ICS, to develop a written response plan (health and safety plan),
and to provide workers with appropriate protective equipment.

One subset of emergency response personnel, known as "skilled support
personnel," support remediation and recovery efforts related to
terrorism (National Clearinghouse for Worker Safety and Health Training,
2002, <http://www.wetp.org/front/NIEHS_rev_010303.pdf>). OSHA requires
that skilled support personnel be trained at a minimum with an
"awareness program" (see Hazardous Waste Operations and Emergency
Response regulation, 29 CFR 1910.120(q)(4)). Additional training
commensurate with worker responsibilities may be required. The safety of
water utility personnel involved in emergency response activities should
be addressed as part of the facility's ERP.

Under the provisions of the FRP, OSHA may provide advice regarding
hazards to persons engaged in response activities and take any other
action necessary to ensure that employees are properly protected.
However, deployed agencies are responsible for protecting the safety and
health of their workers.

A HASP should include information regarding personnel roles, lines of
authority and communication, site security and control, and medical and
emergency alert procedures. The HASP should be developed for the
specifics of the incident so that staff are aware of the common routes
of exposure at a site and are trained in the proper use of safety
equipment and protective clothing and equipment. Safe areas should be
designated for washing, drinking, and eating. To minimize the *impact*
of an emergency situation, field personnel should be aware of basic
first aid and have immediate access to a first aid kit. A suggested
format for a HASP is given in Appendix 9.3, and additional
considerations are described in Module 4, Section 3.1.1.

The document entitled *Occupational Safety and Health Guidance Manual
for Hazardous Waste Site Activities* was jointly developed by the
National Institute for Occupational Safety and Health, OSHA, the United
States Coast Guard, and US EPA (OSHA, 1985,
<http://www.osha.gov/Publications/complinks/OSHG-HazWaste/4agency.html>).
It is intended for those who are responsible for occupational safety and
health programs at hazardous waste sites. While a contaminated water
treatment site may not be a hazardous waste site, many of the health and
safety considerations may be similar. Additional information from OSHA
on safety issues related to emergency preparedness and response can be
found at <http://www.osha-slc.gov/SLTC/emergencypreparedness/index.html>
(OSHA, undated).

### Implementing System Characterization

During system characterization, the activities described in the planning
documents will be implemented to define the nature, extent, and fate of
contaminants in the dinking water system. As with the initial on-site
activities, the system may be considered a crime scene by DOJ/FBI. In
this case, on-site activities should be coordinated with DOJ/FBI or
other law enforcement agencies (e.g., US EPA's Criminal Investigation
Division) that have authority for deciding what actions to take that may
affect evidence-gathering/case development.

During system characterization, the System Characterization Work Plan
and SAP are implemented and sampling data are collected and analyzed to
determine to what extent a contaminated water system poses a threat to
the public, remediation teams, or the environment. The major components
of system characterization include:

-   Conducting sampling in accordance with the FSP;

-   Analyzing samples in accordance with the FSP plan and QAPP;

-   Evaluating results of data analysis to characterize the site and
    conduct risk assessment; and

-   Determining if data are sufficient for developing and evaluating
    potential remedial alternatives.

Because contamination has been confirmed by this stage, some data will
be available. Physical evidence at the site may be sufficient to
tentatively identify the contaminant. "Presumptive" test information
(e.g., indicator parameters or other semi-quantitative test method
results) may indicate the general type of agent such as radioactive,
biological (vegetative cells, spores, viruses or protozoa), or chemical
toxins. In some cases, a laboratory may have *analytically confirmed*
the identity of the contaminant. If the contaminant remains unknown,
then worst-case scenarios may need to be assumed. At this early stage,
investigators should continue to think broadly and consider a wide array
of possibilities, including multiple contaminants. For example,
detection of chemical contamination does not necessarily rule out the
possibility that biological or radiological contamination may be present
as well.

To the extent possible, the system characterization should be expedited
to quickly generate the information needed to select a remedy and
restore safe and reliable drinking water to the affected community. One
strategy for expedited system characterization is US EPA's "*Triad
Approach*." The Triad Approach involves an integration of systematic
planning (as described in Section 2.1), dynamic work plans, and rapid
contaminant analysis to achieve a more streamlined, cost-effective
remediation and recovery. For a small or uncomplicated contamination
incident, or for discrete tasks within a complex contamination incident,
the Triad Approach could enable system characterization activities to
blend seamlessly into remediation activities. Additional information on
the US EPA Triad Approach can be found at
<http://www.epa.gov/tio/triad/> (US EPA, 2004j).

Using the Triad Approach, a *dynamic work plan* guides the project team
in making decisions in the field about how subsequent site activities
will progress. A dynamic work plan relies upon the use of quick
turn-around analytical services (if they exist and can meet analytical
performance standards) to facilitate rapid analysis, and an overall
compressed budget and schedule. A dynamic work plan can be formulated as
a decision tree during the planning phase so that system
characterization activities in the field will provide input to the
maturing conceptual site model on a near real-time basis (e.g., hourly
or daily). In a dynamic work plan, contingency plans are developed in
advance to deal with potential events that are reasonably likely to
occur during the course of site work, such as equipment malfunction, the
unanticipated (but possible) discovery of additional contamination, etc.

The investigation methods that are used must meet the data needs
established in the planning process. Support activities may need to be
arranged before beginning the actual investigation in order to:

-   Ensure access to all areas to be investigated;

-   Procure equipment and supplies in a timely manner;

-   Coordinate with analytical laboratories;

-   Procure on-site facilities for office and laboratory space,
    decontamination equipment, sample storage, and utilities; and

-   Provide for storage and disposal of contaminated material (see also
    Section 5.3 of this module, "Disposal of Remediation Residuals").

Information about the physical characteristics of the system and
affected media should be collected as needed to define potential
transport pathways and exposed populations, and to provide sufficient
engineering data for development and screening of remedial action
alternatives (see also Section 3.3.2 of this module). The information
needed will depend upon the nature of the contaminant and the portion of
the system in which contamination occurs (e.g., the source water,
treatment plant, or distribution network). For example, if the
contamination is confined to the distribution system, then information
would be needed concerning water demand, population served, system
configuration (i.e., map), miles and diameters of mains, number and
location or booster pumps, materials of construction for pipes and
fittings, and entry/exit points.

Geographic information system (GIS) mapping, coupled with hydraulic
modeling software tools, can be used to combine analytical results and
physical features to map, track, model, and estimate the flow and
concentration of contaminants in source water and in the distribution
system. PipelineNet and RiverSpill are examples of software tools that
provide this modeling/GIS capability. Detailed information on GIS and
related tools, and their capabilities [and limitations]{.underline}, is
provided in Module 5, Appendix 8.6.

Characterization should be sufficient to define the physical boundaries
of the study area and to establish the physical system that will be the
subject of remedial action. For example, contamination may be confined
to a specified and isolated section of the distribution system, while
the reservoir, storage tanks, and treatment plant are found to be
"clean." The final objective of the field investigations is to
characterize the nature and extent of contamination so that informed
decisions can be made concerning the level of risk presented by the site
and the appropriate type(s) of remedial response. The results of the
system characterization will be included in the SC/FS report (see
Section 3.3.4).

## Feasibility Study

The feasibility study is the mechanism for development, screening, and
evaluation of alternative remedial actions. It is conducted concurrently
with system characterization and involves identifying remedial action
objectives, identifying potential treatment technologies or other
response actions that will satisfy these objectives, and screening the
candidate technologies. The output of the feasibility study will be a
list of remediation alternatives to be evaluated in greater detail
during the Remedy Selection Study (see Section 4).

### Establishing Remedial Action Objectives

Remedial action objectives specify the contaminants and media of
interest, exposure pathways, and remediation goals that permit a range
of remedial alternatives to be developed. Note that the final
remediation goals (expressed as a contaminant concentration in a medium)
are a subset of the remedial action objectives. The remedial action
objective depends on the exposure pathway. For example, a remedial
action objective for contaminated water that will be treated for
consumption will be different than a remedial action objective for
contaminated water that will be treated and discharged to a river. In
the former case, the remedial action objectives should be protective of
public health, while in the latter case, ecological considerations may
drive the objectives.

The final acceptable remediation goals should be based on a risk
assessment or existing health or technology-based standards (see also
Section 3.1.4 of this module). Ultimately, the degree of treatment
necessary to negate or mitigate the public health effects will depend on
system-specific factors such as the need to treat the water for
consumption, treat to dispose/discharge, and the volume of the water
(e.g., smaller volumes of water may be easier to send off site for
disposal rather than try to treat on-site.).

### Development and Screening of Remedial Alternatives

During the system characterization, information on the physical and
chemical characteristics of the contaminants present in the system
should be reviewed and candidate remedial technologies should be
identified. The objective of screening of remedial alternatives is to
eliminate those remedial technologies that clearly are not applicable to
the contamination incident. The remedial action objectives will drive
the selection of candidate technologies. To be considered as a potential
remediation option, a remediation technology should have the
demonstrated ability to meet the remediation goals based on the
contaminant concentrations present. In some cases, more than one
technology may be needed. As discussed in Section 4, technologies to be
considered may include not only those for treating (or otherwise
handling) contaminated water, but also those for rehabilitating system
components and dealing with other affected environmental media.

The efficacy of various treatment options for specific contaminants
should be included in the WCIT, if they are available (see Module 2,
Appendix 8.9 for more information on the WCIT). Pre-screening of
remedial alternatives via the WCIT will streamline the processes of
specifying a remediation level and selecting a remedy. However, there
are substantial gaps in industry knowledge regarding the efficacy of
various treatment processes for a significant number of contaminants of
concern. Furthermore, the ability of a particular treatment option to
reduce contaminant concentrations to the desired level will depend on
the design and operation of the technology.

Remediation alternatives are developed by assembling combinations of
technologies, and the media to which they would be applied, into
remediation alternatives that address contamination on a system-wide
basis. This process consists of six general steps outlined below:

1.  Establish remedial action objectives specifying the contaminants and
    media of interest (e.g., water, infrastructure material, etc.), and
    PRGs (see Section 3.1.3).

2.  Develop general response actions for each medium of interest,
    defining containment, removal, treatment, or other actions (as
    stand-alone actions or a part of a treatment train) that could be
    taken to satisfy the remedial action objectives.

3.  Identify the amount of water or other affected media (such as system
    components) to be remediated. This analysis should consider the
    remedial action objectives as well as the contaminant
    characteristics.

4.  Identify and screen the technologies applicable to each general
    response action and eliminate those that cannot be implemented
    technically within the system (See also Section 4.1 of this module).
    A wide variety of options should be considered, including innovative
    techniques.

5.  Identify and evaluate technology process options based on
    effectiveness, implementability, and cost.

6.  Assemble the screened technologies into a range of alternatives for
    more detailed evaluation in the Remedy Selection Study (Section 4).

If these steps are done as part of the feasibility study, they should
help expedite the final remedy selection process (Section 4 of this
module) and help determine whether further treatability studies are
needed.

### Treatability Studies

Treatability studies are used to determine a technology's effectiveness
and/or cost for treating the contaminated water, system components, or
other affected media. No treatability study would be needed for a proven
technology if published information allows one to determine its
effectiveness and cost for treating the contaminant. However, it may be
necessary to perform treatability studies for new or unproven
technologies, where there are gaps in knowledge about the effectiveness
and/or cost of a candidate technology, or where the contaminant of
concern is one not commonly encountered in water treatment. US EPA is
compiling treatability information for unconventional contaminants, and
in many cases, treatability studies may be unnecessary.

The basic decision process for deciding whether or not a treatability
study is necessary is described below and outlined in Figure 6-3. The
scope of a treatability study should be scaled to the type of
information needed:

-   Remedy Screening Testing - A relatively quick, low-cost,
    qualitative, bench-scale study might be used to screen a technology
    for possible use.

-   Remedy Selection Testing - Pilot-scale, quantitative testing may be
    needed to verify whether a technology can meet the cleanup criteria
    and at what cost, and/or to optimize operating parameters.

-   Remedial Action Testing -- On-site testing of a full-scale
    remediation system generates detailed design, cost, and performance
    data. However, this level of testing would typically not be
    performed since there will likely be neither time nor need for such
    a study during remediation of a contaminated water system.

Occasionally, special circumstances may call for treatability studies.
For example, use of several treatment technologies as part of a
treatment train may require a treatability study to evaluate the most
effective process sequence and combination of operating parameters for
treating the contaminated water. Or a treatability study may be
warranted when remediation will likely be a long-term endeavor. In this
case, the time and cost of such a study may ultimately result in a more
effective and efficient remediation process.

Regardless of the scale and scope of a treatability study, both a
Treatability Study Work Plan and a Treatability Test Evaluation Report
should be prepared. The Treatability Study Work Plan specifies test
objectives, specialized equipment and materials needed, treatment test
procedures, parameters to measure, analytical methods, data management
procedures, data analysis and interpretation, health and safety, and
residuals management.

The Treatability Test Evaluation Report describes testing performed,
results of the tests, interpretation of the results, and integration of
the results into the remedy selection process. The report also should
describe the effectiveness of the treatment technology and estimated
costs for application of the technology at full scale. More information
on treatability studies can be found in *A Guide for Conducting
Treatability Studies Under CERCLA* (US EPA, 1992a,
<http://www.epa.gov/superfund/resources/remedy/pdf/540r-92071a.pdf> ).
Again, while all of the statutory and procedural aspects of CERCLA do
not necessarily apply to a drinking water contamination incident, the
technical content of this guidance may be useful for water system
remediation treatability studies.

![](media/image1.wmf)

[]{#__RefHeading___Toc70487197 .anchor}Figure 6-3. Process for
Evaluating the Need for a Treatability Study

(modified from USEPA, 1988a,
<http://www.epa.gov/superfund/action/guidance/remedy/rifs/overview.htm>)

### System Characterization/Feasibility Study (SC/FS) Report

A SC/FS Report should be prepared to document data collection
activities, provide inputs to the risk assessment, and facilitate
screening of remedial options. A suggested format for a SC/FS Report is
presented in Appendix 9.4.

# Analysis of Alternatives and Remedy Selection

The process of choosing and implementing an appropriate remedial
response to system contamination must provide a remedial response to
"negate or mitigate deleterious effects on public health caused by the
introduction of contaminants into water intended to be used for drinking
water" (Public Law 107-188, June 12, 2002). If the FRP is activated, US
EPA will likely be the lead agency for remediation of contaminated
water, system components, and environmental media.

It is generally assumed that the primary target of intentional
contamination of a water system is the water itself. However,
contaminants could also affect the components of the water distribution
system such as storage tanks, filters, pipes, and pumps, or even
household plumbing and sewer systems. Additionally, other media may be
affected (such as soil, lake sediment, or biota), or air/solid
contamination may be of concern (via spills, phase separation, or
partitioning from the water phase to the solid or gas phase). Thus,
remediation activities need to consider the water, system components,
and affected environmental media.

## Analysis of Alternatives

Once remedial action objectives are defined and a list of remediation
alternatives is established, a detailed analysis of remediation
alternatives should be performed. The detailed analysis of alternatives
consists of the analysis and presentation of the relevant information
needed to allow decision makers to select a remedy that will satisfy the
remedial action objectives. The remedy may include treatment,
containment, removal, disposal, institutional actions, or a combination
of these. During the detailed analysis, each alternative is assessed
against the remedy evaluation criteria (Section 4.2). The detailed
analysis of alternatives follows the development and screening of
alternatives during the feasibility study and precedes the actual
selection of a remedy.

The evaluations conducted during the detailed analysis phase build on
previous evaluations conducted during the development and screening of
alternatives. This analysis also incorporates any treatability study
data and additional information that may have been collected during the
system characterization. The results of the detailed analysis support
the final selection of a remedial action.

Most remedial alternatives fall into one of three technology
categories---containment technologies, extraction or removal
technologies, or treatment technologies. Other measures may include
natural attenuation, institutional controls (e.g., deed restrictions,
use restrictions, access control, and notices), or no further action.
For contaminated water, treatment or natural attenuation may be the most
appropriate alternatives. For system components, treatment (i.e.,
decontamination) or removal and replacement may be necessary.
Remediation of environmental media may entail consideration of the full
range of alternatives. The following sections provide an overview of
treatment technologies and other remedial response actions that may need
to be considered, including no action (Section 4.1.1), treatment of
contaminated water (Section 4.1.2), rehabilitation of system components
(Section 4.1.3), and remediation of environmental media (Section 4.1.4).

### No Additional Action Alternative

Under the "no additional action" alternative, no remedial activities
would be implemented. Under this alternative, human health and
environmental risks are reduced only through attenuation and/or
degradation of the contaminant. This may be a realistic alternative in
cases where these processes would proceed fast enough to reduce the
contaminant concentration to acceptable levels within a reasonable
period of time and where an alternate water supply is available during
this period (see Section 6 of this module). Even if it is not feasible,
the "no-additional-action" alternative provides a baseline for comparing
other alternatives.

### Alternatives for the Treatment of Contaminated Water

Contaminated water may be present throughout the distribution system or
may be isolated to specific areas such as a water source (e.g.,
reservoir), isolated area of the distribution system, or storage tank.
In many cases, this contaminated water may need treatment. The
objectives of treatment could be to make the water acceptable for direct
use or sanitation or to pretreat the water prior to disposal (see
Section 5.3 of the module for discussion of potential disposal
requirements).

The extent to which additional treatment equipment is needed may depend
on the location of the contaminated water. For example, when
contamination is present in a water source or storage tank upstream of
an existing treatment plant, the remedial response may be able to use
existing treatment equipment. When contaminated water is present in a
distribution system, some consideration should be given to the method
which most effectively removes the water for treatment. In some cases,
it may be best to avoid draining the system because of fire hazard and
the possibility that some empty mains might collapse. In other cases,
the contaminated part of the system might be hydraulically isolated from
the rest of the system. If system pressure cannot be used to remove the
contaminated water, there may be a need to pump the water out. See
Section 4.1.3 of this module, under "flushing system," for additional
discussion of removing contaminated water.

This section describes technologies that may be considered for treatment
of contaminated water, either as existing equipment or as additional
temporary equipment. Table 6-2 summarizes water treatment technologies
for treating various contaminants. While these technologies
traditionally are used for removal of typical drinking water
contaminants, they also may be applicable in dealing with intentional
source water contamination or, on a smaller scale, treating stored water
affected by a contamination incident. Furthermore, these proven drinking
water treatment technologies provide a reasonable starting point for the
selection of technologies for remediation of intentionally contaminated
water. Performance data for these processes may be available for the
intentional contaminant(s) of concern, or for similar contaminants.

The columns in Table 6-2 represent broad contaminant groups. There is
wide variability for specific contaminants within a contaminant group,
and treatment efficacy will be a function of the design and operation of
the specific process. US EPA's WCIT, when available, will be a resource
for more detailed information on the treatment effectiveness of
particular technologies (see Module 2, Appendix 8.9 for more information
on the WCIT).

While biotoxins are not specifically called out in Table 6-2, processes
that are effective for inactivating synthetic and other non-volatile
organic compounds may be effective for certain biotoxins. Furthermore,
for some biotoxins, oxidation processes such as chlorination and
ozonation would be highly effective.

[]{#__RefHeading___Toc69893189 .anchor}Table 6-2. Summary of Potentially
Applicable Water Treatment Technologies

  ------------------------ ------------------------ ------------------------ ------------------------ ------------------------ ------------------------
                           **Contaminant Group**                                                                               

  **Treatment Technology** Inorganic Chemicals      Microbes                 Radionuclides            Synthetic and Other      Volatile Organic
                                                                                                      Non-Volatile Organic     Chemicals
                                                                                                      Chemicals                

  Activated Alumina (AA)   ![](media/image2.png)    ![](media/image3.png)    ![](media/image4.png)    X                        X

  Activated Carbon         ![](media/image5.png)    X                        ![](media/image6.png)    ![](media/image7.png)    ![](media/image8.png)

  Air Stripping            ![](media/image9.png)    ![](media/image10.png)   ![](media/image11.png)   ![](media/image12.png)   ![](media/image13.png)

  Chloramination           X                        ![](media/image14.png)   ![](media/image15.png)   X                        X

  Chlorination             ![](media/image16.png)   ![](media/image17.png)   ![](media/image18.png)   X                        ![](media/image19.png)

  Chlorine Dioxide         ![](media/image20.png)   ![](media/image21.png)   ![](media/image22.png)   X                        ![](media/image23.png)

  Coagulation/Filtration   ![](media/image24.png)   ![](media/image25.png)   ![](media/image26.png)   ![](media/image27.png)   ![](media/image28.png)

  Direct Filtration        X                        ![](media/image29.png)   X                        X                        X

  Ion Exchange             ![](media/image30.png)   ![](media/image31.png)   ![](media/image32.png)   ![](media/image33.png)   ![](media/image34.png)

  Microfiltration,         X                        ![](media/image35.png)   X                        ![](media/image36.png)   ![](media/image37.png)
  Ultrafiltration                                                                                                              

  Ozonation                ![](media/image38.png)   ![](media/image39.png)   ![](media/image40.png)   ![](media/image41.png)   ![](media/image42.png)

  Reverse Osmosis (RO),    ![](media/image43.png)   ![](media/image44.png)   ![](media/image45.png)   ![](media/image46.png)   ![](media/image47.png)
  Nanofiltration (NF)                                                                                                          

  Ultraviolet (UV)         ![](media/image48.png)   ![](media/image49.png)   ![](media/image50.png)   X                        ![](media/image51.png)
  Disinfection                                                                                                                 

  Advanced Oxidation       ![](media/image52.png)   ![](media/image53.png)   ![](media/image54.png)   ![](media/image55.png)   ![](media/image56.png)
  ------------------------ ------------------------ ------------------------ ------------------------ ------------------------ ------------------------

Note that the contaminant groups presented in this table are very broad,
so a given technology might not necessarily be applicable to a specific
contaminant within a given group. Thus, more information will be
necessary to inform treatment decisions and this table is for guidance
only.

Symbols:

> ![](media/image57.png) Typically most effective for this contaminant
> group.
>
> ![](media/image58.png) Typically less effective for this contaminant
> group.

![](media/image59.png) Typically not effective for this contaminant
group.

> X Insufficient data to determine effectiveness for this contaminant
> group.

The treatment technologies listed in Table 6-2 are briefly described
below, to provide a general overview. These descriptions alone should
not be used to select a final remedy or design a treatment process. Many
of these technologies are available from a number of commercial vendors.
The American Water Works Association (AWWA) provides a listing of
vendors of water treatment equipment and supplies at
<http://www.awwa.org/buyersguide/> (AWWA, 2004c), although other vendors
may exist. Note that equipment and supplies from any given vendor may or
may not be suitable for use during remediation and recovery activities.

In addition to the individual technologies discussed below, it may be
appropriate to use a combination of technologies as part of a treatment
train. Examples could include ozonation followed by
coagulation/filtration, ozonation followed by granular activated carbon,
powdered activated carbon addition followed by coagulation/filtration,
or coagulation followed by microfiltration.

-   **Activated Alumina (AA)** --- The use of AA involves a physical and
    chemical process in which ions in the water are adsorbed onto an
    oxidized AA surface (US EPA, 1998a,
    <http://www.epa.gov/safewater/standard/tlisttcr.pdf>). The solid AA
    is present as a packed stationary bed within one or more vessels. As
    the water passes through the vessel(s) the AA adsorbs the
    contaminant, allowing treated water to exit the bed. AA is made by
    treating aluminum ore so that it becomes highly porous and
    adsorptive (USAEC, 2002,
    <http://www.frtr.gov/matrix2/top_page.html>).

> *Effectiveness:* AA will remove inorganic cations and anions such as
> metals and fluoride, as well as natural organic matter (AWWA, 1999).
> It has also been used for removal of radium (AWWA, 1999). AA is
> appropriate only for inorganic chemicals and radionuclides. No data
> are available to demonstrate the effectiveness of this technology on
> pathogens; however, it is not expected to be effective for this
> application. Factors affecting removal efficiency include
> concentration of the target contaminant, oxidation state of the
> contaminant to be removed, pH of the water, presence of other
> contaminants that may adsorb to the activated sites (i.e., competitive
> adsorption), contact time, and regeneration method. Water-soluble
> compounds and small molecules may not be adsorbed well. At high
> contaminant concentrations, replacement of AA will need to be more
> frequent to ensure effectiveness. Constituents can interfere with the
> adsorption process by competing with adsorption sites or clogging the
> pores; these constituents include oily substances, dissolved solids,
> natural organic matter, and ions such as chloride.
>
> *Residuals Generated:* AA has a finite number of adsorption sites.
> Therefore, packed beds will need replacement or regeneration on a
> regular basis. Regeneration is conducted by rinsing with regenerant
> (typically a strong base such as sodium hydroxide), flushing with
> water, and neutralizing with acid. The spent regenerant is corrosive,
> contains high levels of impurities and the contaminant, and contains
> dissolved aluminum. Typically, regenerant brine is discharged to an
> evaporation pond and the water is allowed to evaporate. The remaining
> dried salts can then be disposed of in a landfill (US EPA, 1998a,
> <http://www.epa.gov/safewater/standard/tlisttcr.pdf>). For remedial
> action, an alternative brine management method (e.g., comprising
> tanks) may be necessary. Where contaminant concentrations are high (as
> may be possible in a remedial situation), frequent backwashing or
> replacement of AA may be needed, generating residual waste.
>
> *Implementation and Flexibility:* Alumina is commercially available in
> bulk containers and bags, which can be, contained in filtration or
> reaction units during operation. Typical applications include water
> treatment and process industries where backwashing and regeneration
> can easily be done. The technology is generally not used (or is used
> infrequently) for remediation applications.

-   **Activated Carbon** --- Activated carbon is similar to charcoal in
    composition, but has its surface altered to enhance its adsorption
    properties. Contaminants are removed by adsorption to the carbon
    surface. There are two common types of activated carbon treatment
    used for drinking water, granular activated carbon (GAC), in which
    water is passed through one or a series of packed beds, and powdered
    activated carbon (PAC), which is added loosely to water (US EPA,
    1998a, <http://www.epa.gov/safewater/standard/tlisttcr.pdf>). A
    variant on PAC is the Powdered Activated Carbon Treatment (PACT)
    process, used in wastewater treatment application, which combines
    PAC with biological treatment.

> *Effectiveness:* Activated carbon adsorption is appropriate for
> treatment of dissolved organic compounds and, to a lesser extent,
> dissolved metals and other inorganic contaminants. Activated carbon is
> most effective for aromatic and nonpolar organic compounds; it is less
> effective for aliphatic and polar organic compounds. The most
> effective metals removal is achieved with metal complexes. Impurities
> such as suspended solids (over 50 ppm) and oil and grease (over 10
> ppm) reduce the effectiveness of GAC. Operating conditions affecting
> performance include temperature, pH, empty bed contact time, and level
> of dissolved natural organic matter in the water.

For PAC to be effective, it is essential that all water come into
contact with the PAC. As a result, PAC treatment should occur in a
mixing basin that assures sufficient contact time (US EPA, 1998a,
<http://www.epa.gov/safewater/standard/tlisttcr.pdf>). For the PACT
process, the basin should also be aerated for successful biological
treatment to occur.

> *Wastes Generated:* Over time, the activated carbon in a GAC system
> reaches its limit in removal of contaminants. This is determined
> through monitoring contaminant concentrations in the effluent
> (treated) water. The length of time is determined by the adsorptive
> capacity of the contaminants and their concentration (including
> interfering, non-target contaminants). When the level of contaminant
> in the effluent water reaches an unacceptable level, the carbon
> contactor is taken off-line, and a new contactor with fresh or
> regenerated carbon is brought on line to take its place. The spent GAC
> in the contactors can be removed and regenerated, or removed and
> disposed. The spent GAC may contain high levels of contaminants.

PAC should be removed from the water to ensure contaminant removal and
to prevent effluent discoloration. The spent material, which may contain
high levels of contaminants, is settled or filtered from the water and
the activated carbon is either regenerated or disposed of after use.

> *Implementation and Flexibility:* GAC is the most common application
> of activated carbon in remedial action applications (USAEC, 2002,
> <http://www.frtr.gov/matrix2/top_page.html>). GAC beds have been used
> in water treatment for many years, but usually for taste and odor
> control, not contaminant removal. There are, however, full-scale
> applications of GAC for removal of synthetic organic compounds,
> natural organic matter, and other organic materials.
>
> If kept air tight, the carbon can be stored indefinitely until use.
> Because it is a granular medium, GAC systems can be configured in a
> variety of containers and sizes including drums, trays, canisters, and
> filters. The type and size of a GAC system is determined by the
> particular application and required adsorptive capacity. GAC systems
> are widely commercially available from a number of vendors. For
> example, GAC beds are available as mobile pre-engineered skid mounted
> units for temporary remedial applications of ground water cleanup,
> drinking water purification, quick-response actions, and other water
> treatments. In these applications, the GAC contactors are connected to
> existing piping and utilities at the site.

Care should be taken to monitor the effluent from GAC systems to detect
contaminant breakthrough, indicating saturation of the adsorptive
capacity. To safeguard against such breakthrough, GAC systems often
consist of consecutive trays or drums so that breakthrough is captured
in downstream GAC units and the upstream component is taken off line and
replaced.

-   **Advanced Oxidation Processes** --- In advanced oxidation
    processes, contaminant removal is achieved through the combined
    effect of strong oxidants (and potentially UV light) on water
    contaminants (USAEC, 2002,
    <http://www.frtr.gov/matrix2/top_page.html>). This process is often
    synergistic (i.e., results in more effective removal than the simple
    sum of the two treatments). For example, some advanced oxidation
    processes use combinations of oxidants (e.g., ozone and hydrogen
    peroxide), while others use UV light with oxidants such as ozone or
    hydrogen peroxide.

> *Effectiveness:* The technology is not only effective for disinfecting
> pathogens, but also for destroying organic chemicals that react with
> the hydroxyl radical or with UV light. Chemicals that can be treated
> by advanced oxidation processes include petroleum hydrocarbons,
> chlorinated hydrocarbons, and ordnance compounds (e.g., TNT, or
> trinitrotoluene). Typically, organic chemicals with double bonds
> (e.g., tetrachloroethylene) and simple aromatic compounds (e.g.,
> toluene) are easily destroyed in advanced oxidation processes. A major
> drawback is that turbidity and high concentrations of metals or oils
> may significantly and dramatically reduce the effectiveness of this
> treatment, so that pretreatment of the water may be necessary under
> these conditions (USAEC, 2002,
> <http://www.frtr.gov/matrix2/top_page.html>).
>
> *Wastes Generated:* There are no waste products generated from the
> operation of advanced oxidation processes; however, some organic
> chemical oxidation byproducts may form in the treated water, and the
> health effects associated with these byproducts should be considered
> if the water will be used by the public following treatment.
>
> *Implementation and Flexibility:* Since advanced oxidation utilizes
> existing UV disinfection equipment and processes, as well as
> commercially available oxidants, there are many vendors and sources of
> the technology. For example, the technology has been used extensively
> in the remediation of ground water contaminated with organic chemicals
> (USAEC, 2002, <http://www.frtr.gov/matrix2/top_page.html>). Advanced
> oxidation is available in skid-mounted units of modular design,
> allowing for its application in temporary and/or mobile applications
> such as may be present in remediation of a water distribution system.
> Implementation, flexibility, and limitations are similar to those
> described for UV disinfection and oxidants such as ozone, as described
> later in this section.

-   **Air Stripping** --- Air stripping is a separation process in which
    volatile organic contaminants are physically transferred or stripped
    from the water to the air. After contact with the contaminated
    water, the air is swept out of the system to avoid contaminating the
    treated water (US EPA, 1998a,
    <http://www.epa.gov/safewater/standard/tlisttcr.pdf>). Air stripping
    equipment can include packed towers, diffused aeration tanks, tray
    aeration towers, and spray aerators.

> *Effectiveness:* Air stripping is most effective for the removal of
> nonpolar, semi-volatile and volatile organic compounds, certain
> pesticides, and fuels from water. Air stripping is ineffective for
> chemicals that do not readily volatilize from water, such as metals
> and PCBs, and it is not appropriate for pathogens. Other factors
> affecting effectiveness include temperature and the presence of
> impurities, such as inorganic compounds or microbes in the water,
> which can cause fouling of the equipment (US EPA, 2001b,
> <http://www.epa.gov/tio/pubitech.htm>). High temperature and
> turbulence can reduce the thickness of the air-water boundary layer
> and thus improve transfer of volatile organic compounds to the air
> phase (AWWA/ASCE 1998). The air-to-water ratio is a design factor
> equal to the amount of air used to the amount of water passing through
> the system, and a higher air-to-water ratio provides a higher level of
> volatile organic compound removal (AWWA/ASCE 1998).
>
> *Wastes Generated:* Contaminant*s* in the water are partitioned to the
> air. Therefore, prior to discharge, the contaminated exhaust air may
> need to be treated if there are concerns regarding air quality
> compliance and human exposure. Off-gas may need to be treated using a
> scrubber or air filter containing an adsorptive media.
>
> *Implementation and Flexibility:* Air stripping technology is commonly
> used for ground water cleanup (US EPA, 2001b,
> <http://www.epa.gov/tio/pubitech.htm>). Air stripping units are
> commercially available in pre-engineered skids or trailers for
> mobility and flexibility. Air stripping may be conducted in a packed
> tower installation or an aeration tank (USAEC, 2002,
> <http://www.frtr.gov/matrix2/top_page.html>). Air strippers come in a
> variety of package plant configurations and capacities. For example,
> the type and size of the air blower/compressor is selected based on
> the particular flow rate and operating pressure. Various optional
> components such as silencers and meters can be ordered and factory
> installed. Air stripping technology is simple to configure at a
> treatment site; most components are factory assembled and can be
> prepositioned. It can be operated continuously, thereby simplifying
> maintenance and operations.

-   **Chloramination** --- Chloramination is a disinfection process in
    which ammonia and a free chlorine compound (chlorine gas or
    hypochlorite) are added to water. These two chemicals react to form
    chloramines. An advantage to the use of chloramination over other
    disinfectants is stable residual concentration and lower production
    of disinfection byproducts. However, chloramines typically are less
    effective germicides compared to free chlorine and, therefore, need
    longer contact times to achieve similar kill levels. In addition,
    chloramines are toxic to dialysis patients, fish, and aquaculture
    operations (OWASA, 2002,
    <http://www.owasa.org/pages/chloramination.pdf>).

> *Effectiveness:* In a given contact time, chlorination has a higher
> germicidal efficiency than chloramination, but with enough contact
> time, monochloramine, one of the more prominent chloramines at typical
> pHs, may be effective in treating certain types of bacteria
> (Tchobanoglous, 1991). The effectiveness of chloramination is a
> function of pH, contact time, disinfectant concentration, temperature,
> and oxidant demand. As with chlorination, the technology provides
> disinfection for pathogens, but does not remove contaminants.
>
> *Wastes Generated:* There are no waste byproducts generated from
> chloramination. However, chloramines may react with some compounds in
> aqueous solution, and the health effects associated with these
> reaction products should be considered if the water will be used by
> the public following treatment. Reaction products of concern include
> known disinfection byproducts, which may have chronic health effects,
> as well as the oxidation/chlorination byproducts of the contaminant.
> This latter group may be of greater concern if there is the potential
> for formation of acutely toxic products.
>
> *Implementation and Flexibility:* Equipment and reliability of
> chloramination as a disinfectant are comparable with chlorination; the
> chemistry and reagents are different, but the injection and controls
> are the same. Systems can be sized from small throughput to large
> municipal systems, and the equipment and chemicals are widely and
> commercially available.

-   **Chlorination** --- Chlorination is a process in which chlorine gas
    or hypochlorite solids or solutions are added to water at a specific
    dose and allowed to remain in contact with the water for a specific
    time prior to further treatment or distribution. When added to water
    at typical drinking water pHs, both chlorine gas and hypochlorite
    form hypochlorous acid (free chloride ion is additionally formed
    from chlorine gas) (AWWA, 1999).

> *Effectiveness:* Chlorine is a strong oxidizing agent that kills
> vegetative bacteria, viruses, and some protozoa and spores -- although
> not all. Chlorination may also oxidize some odor and color-causing
> compounds as well as some metals and organic compounds. The rate of
> disinfection depends on the concentration and form of the chlorine
> compound, contact time, pH, and temperature (Hammer, 1996).
>
> *Wastes Generated:* There are no wastes generated as a result of
> chlorination technology. However, chlorine will react with a variety
> of compounds in aqueous solution, and the health effects associated
> with these reaction products should be considered if the water will be
> used by the public following treatment. Reaction products of concern
> include regulated disinfection byproducts (e.g., trihalomethanes and
> haloacetic acids) which may cause chronic health effects, and
> compounds formed by reaction between chlorine and the target
> contaminant. This latter group may be of greater concern if there is
> the potential for formation of acutely toxic products.
>
> *Implementation and Flexibility:* Free chlorine systems are available
> in a variety of configurations and sizes. Chlorine gas has been used
> reliably for disinfection of drinking water for the history of modern
> drinking water treatment. Recently, interest has grown in the use of
> hypochlorite solutions to avoid the hazards and vulnerabilities
> associated with gaseous chlorine. The equipment and chemicals for
> chlorination are widely and commercially available. Chlorine gas is
> hazardous and necessitates isolated space as well as increased worker
> training and protection (US EPA, 1998a,
> <http://www.epa.gov/safewater/standard/tlisttcr.pdf>). Chlorine gas
> addition involves gas cylinder storage, a series of valves and
> connections, and an injector to mix the gas and water. Addition of
> solutions of free chlorine compounds (e.g., hypochlorite) involves raw
> material storage, a pump, and chemical injection (Hammer, 1996).

-   **Chlorine Dioxide** --- In water treatment applications, gaseous
    chlorine dioxide is generated using chlorine gas and sodium chlorite
    or hydrochloric acid and sodium hypochlorite. The gaseous chlorine
    dioxide is dissolved in the water flow (AWWA, 1999). Generated
    chlorine dioxide solution will contain small amounts of chlorine as
    an impurity (White, 1992).

> *Effectiveness:* Chlorine dioxide is a strong oxidizing agent that is
> typically used for taste and odor control, primary disinfection, and
> oxidation of metals during drinking water treatment (AWWA, 1999).
> Chlorine dioxide will oxidize certain inorganics such as iron and
> manganese (White, 1992). Like chlorine, it is effective for killing
> vegetative bacteria, viruses, and some protozoa and spores -- although
> not all. Chlorine dioxide is typically a more effective biocide than
> free chlorine, particularly at higher pH levels; unlike chlorine, it
> does not dissociate at normal drinking water pH levels (AWWA/ASCE
> 1998). The effectiveness of chlorine dioxide is a function of contact
> time, disinfectant concentration, temperature, and oxidant demand;
> effectiveness is generally not affected by changes in pH within the pH
> range of 6 to 10 (White, 1992).
>
> *Wastes Generated:* There are no wastes generated from the use of
> chlorine dioxide technology. However, chlorine dioxide will react with
> a variety of compounds in aqueous solution, and the health effects
> associated with these reaction products should be considered if the
> water will be used by the public following treatment. Reaction
> products of concern include regulated disinfection byproducts (e.g.,
> chlorate and chlorite), which may have chronic health effects, and
> compounds formed by reaction between chlorine dioxide and the target
> contaminant. This latter group may be of greater concern if there is
> the potential for formation of acutely toxic products.
>
> *Implementation and Flexibility:* Chlorine dioxide generators are
> available from various manufacturers for drinking water and industrial
> applications. Using chlorine dioxide for disinfection is similar to
> using gaseous chlorine; it is injected directly into the water stream.
> However, it has been used much less frequently than chlorination.
> Nevertheless, chlorine dioxide generation systems are readily
> available as skid mounted units. Chlorine dioxide is expected to be
> available for use in centralized treatment of source water or for
> mobile treatment of water in a water distribution system, alone or in
> combination with other technologies.

-   **Coagulation/Filtration or Direct Filtration** --- This process
    removes suspended particles from water and also can remove certain
    dissolved inorganic and organic contaminants. In conventional
    filtration, a coagulant (e.g., aluminum salts, iron salts, or
    cationic polymers) is added to water. In subsequent mixing steps, it
    binds with solids and combines into larger aggregate particles
    termed flocs. Larger flocs are typically removed by sedimentation
    (although dissolved air floatation my be used in some cases), while
    finer particles are removed by media filtration (e.g., a sand bed).
    Periodically, the filter is backwashed to remove the collected
    particles. In direct filtration, there is no clarification step.
    After addition of a coagulant, the water is passed directly through
    the filter following flocculation. While suitable for a similar
    class of solid contaminants, its effectiveness is lower due to the
    omission of this sedimentation pretreatment step.

> *Effectiveness:* Coagulation/filtration is effective primarily for
> removing solids and microbial contaminants but may also remove some
> inorganic and organic contaminants. Several factors affect the
> coagulation process, including pH, coagulant dosage, coagulant type,
> the concentration and variability of the feed stream contaminant, and
> mixing characteristics (Casey, 1997). Coagulation is less effective at
> lower temperatures (Casey, 1997). Direct filtration may not be
> effective for water with an average turbidity above 10 NTU or a
> maximum turbidity above 20 NTU (US EPA, 1998b,
> <http://www.epa.gov/OGWDW/standard/tlstnm.pdf>). System performance is
> sensitive to the coagulation chemistry and either under- or
> over-dosing of the coagulant can adversely impact the removal of
> particulate and microbiological contaminants (US EPA 1998a,
> <http://www.epa.gov/safewater/standard/tlisttcr.pdf>).
>
> *Wastes Generated:* The most significant residual is the sludge from
> sedimentation basins, removed typically on a continuous basis (Casey,
> 1997). The sludge can be further thickened prior to disposal,
> typically in landfills (although alterative management may be needed
> if the residual poses a hazard from treating contaminated water). The
> filter backwash represents another waste stream (Casey, 1997).
>
> *Implementation and Flexibility:* These technologies have been applied
> to both drinking water and wastewater treatment (Casey, 1997). The
> process necessitates operator attention and monitoring (US EPA 1998a,
> <http://www.epa.gov/safewater/standard/tlisttcr.pdf>). Although
> pre-engineered modular units are available, the units are typically
> applied to treatment of source water. For example, the typical package
> or modular plant has been used for a variety of applications including
> hospital, resort, andsmall town sewage treatment, as well asindustrial
> plant and golf course water reuse. Such water treatment package plants
> still entail considerable mobilization and planning in design and
> field construction. Therefore, this process is only practical for
> centralized water treatment.

-   **Ion Exchange** --- Ion exchange is a process whereby a positively
    or negatively charged ion on a solid exchanges with a similarly
    charged contaminant ion in the drinking water. The solid is
    typically a synthetic ion exchange resin present as a packed
    stationary bed within one or more vessels; as the water passes
    through the vessel(s) the resin captures the contaminant, allowing
    treated water to exit the bed.

> *Effectiveness:* Ion exchange is effective only on charged species.
> Examples of such species are dissolved ionic metals (including ionic
> radionuclides), nonmetallic anions such as cyanide, and charged
> organic compounds such as organic acids and amines. Factors affecting
> removal efficiency include pH, *chemical speciation*, competing ions,
> contact time, regeneration method, functional group of the resin's ion
> exchange sites, and oxidation state of the ion to be removed. In
> general, larger, strongly charged ions (i.e., divalent and trivalent
> ions) are most effectively captured in ion exchange. However, ion
> exchange resin with reverse selectivity (monovalent over divalent and
> trivalent ions) is also available.
>
> *Wastes Generated:* Ion exchange resin beds need to be regenerated on
> a regular basis. As with adsorption technologies, the resin reaches
> its limiting capacity to remove contaminants over time as it adsorbs
> more and more contaminants. When this happens, the bed is taken
> off-line and regenerated in-situ using a series of strong acid or base
> solutions and water. When regeneration is no longer possible, the bed
> is replaced. The regenerant solution is typically corrosive and
> contains high levels of contaminants.
>
> *Implementation and Flexibility:* Ion exchange systems are very
> flexible and can be configured and sized to treat a variety of
> different flow rates. There are many manufacturers and vendors,
> although generally the ion exchange "beds" and associated canisters
> are designed for a specific application (e.g., preparing laboratory or
> filtered drinking water). However, ion exchange systems are designed
> to remove particular ionic species; contaminants that are not ionic in
> nature will not be removed by ion exchange and indeed could foul such
> systems if not removed prior to entering the ion exchange resin
> bed(s). Also, a single bed cannot remove both positively and
> negatively charged ions. Instead, several different beds are typically
> used in series for this purpose.
>
> Although many types of ion exchange resins are commercially available,
> most systems are designed for removing common drinking water
> impurities such as hardness (calcium) or trace metals. Removing
> uncommon contaminants, for example, explosive or energetic compounds,
> may call for specialty resins, increasing costs and potentially
> requiring research and development efforts. Impurities in the water
> such as calcium may compete for ion exchange sites on the resin,
> lowering the effectiveness of the resin in removing target
> contaminants. The technology requires storage capacity for liquid
> hazardous substances such as regeneration solution and spent
> regenerant, but the beds of ion exchangers can be stored indefinitely
> until use.

-   **Microfiltration, Ultrafiltration** --- Microfiltration and
    ultrafiltration are pressure-driven membrane filtration processes
    that separate contaminants from water primarily due to size
    exclusion (i.e., the contaminant is too large to pass through the
    membrane pores). Additionally, charge interactions may play a role
    in contaminant removal. Both microfiltration and ultrafiltration
    technologies use membranes, which are engineered polymeric or
    ceramic barriers that allow water to permeate but prevent larger
    particles, microorganisms, and potentially some macromolecular
    organic compounds from passing through. The type of membrane
    material and its pore size determines the degree to which particular
    contaminants are rejected (US EPA, 2003f,
    <http://www.epa.gov/safewater/lt2/guides.html>).

> *Effectiveness:* Microfiltration is generally applied for the removal
> of particles and microorganisms larger than virus (e.g., bacteria and
> protozoa). Ultrafiltration membranes have much smaller pore openings
> and are capable of removing virus in addition to larger
> microorganisms. Furthermore, many ultrafiltration membranes can remove
> macromolecular organic compounds. Since both of these filtration
> processes are capable of removing particulate matter, they may remove
> certain dissolved contaminants that are associated with, or adsorbed
> to, particulate matter. Removal of contaminants by micro- and
> ultrafiltration may also be enhanced by the formation of a cake layer
> on the membrane surface.
>
> *Residuals Generated:* Aqueous residuals (including backwash and
> chemical cleaning waste) are generated from periodic cleaning. In some
> designs, a concentrate stream may also be continuously generated.
> Normally, these residuals are discharged to surface water or sewage
> systems (US EPA, 2003f,
> <http://www.epa.gov/safewater/lt2/guides.html>). However, when used in
> response to a contamination incident, additional treatment of these
> residuals may be needed to remove the contaminants of concern.
>
> *Implementation and Flexibility:* Microfiltration and ultrafiltration
> membranes are commercially available from a number of vendors as
> modules in which the membrane and housing are designed as an integrate
> unit. Multiple modules are connected in parallel, and occasionally in
> series, to form membrane filtration units. The filtration units may be
> skid mounted or submerged in tanks and connected by manifolds. This
> provides flexibility in design since increased treatment capacity is
> easily obtained by increasing the number of modules arrayed in
> parallel. Improved removal efficiency, or more reliable treatment, is
> achieved through the use of a multi-pass system in which the membrane
> filtration units are connected in series. Filtration is based on
> contaminant size; contaminants smaller than the pore size of the
> membrane will generally not be removed in a reliable or efficient
> manner. The addition of a coagulant prior to microfiltration
> (coagulation-assisted microfiltration) can make this technology an
> option for removal of arsenic, and possibly for other inorganics.
> Addition of powdered activated carbon prior to microfiltration or
> ultrafiltration may make the technology effective for removal of
> organic contaminants.
>
> Feed water typically needs pretreatment (e.g., filtration, chemical
> conditioning) to remove foulants or prevent membrane damage. Membranes
> can also be damaged or degraded by oxidants, but some membranes,
> typically produced from a variation of polysulfone, are resistant to
> oxidants. Backwashing and chemical cleaning are necessary periodically
> to remove the particulate matter that accumulates over the course of a
> filtration cycle, or to remove foulants that have adsorbed to the
> membrane surface (US EPA, 2003f,
> <http://www.epa.gov/safewater/lt2/guides.html>).

-   **Ozonation** --- Ozonation is a disinfection/oxidation process
    using ozone gas, a strong oxidizing agent. The ozone gas is
    generated on-site and dissolved in water, where it rapidly reacts
    and decomposes (AWWA, 1999).

> *Effectiveness:* Ozone rapidly inactivates some, but not all,
> microorganisms and reacts with certain organic chemicals (Hammer,
> 1996). A detailed investigation of the effectiveness of ozone in
> killing protozoan parasites has been performed (US EPA, 2001c,
> <http://www.epa.gov/etv/verifications/vcenter2-9.html>). A summary of
> treatment data (US EPA, 1998b,
> <http://www.epa.gov/OGWDW/standard/tlstnm.pdf>) indicates that, within
> specific ranges for pH, temperature, ozone concentration, and contact
> time, Hepatitis A virus, *Giardia* cysts, and poliovirus can be
> inactivated. At high pH, above 8 to 9, ozone decomposes to form the
> highly reactive hydroxyl radical. This is generally a more effective
> disinfectant and a stronger oxidant. Alkalinity, however, can consume
> hydroxyl at high pH, and competitive reactions may consume the
> hydroxyl radical before the target contaminant is oxidized. Therefore,
> optimal pH may be site-specific, and maintaining the appropriate pH is
> necessary for effective and consistent disinfection or oxidation. The
> feed gas used in ozone generation can be air or pure oxygen. The
> quality of the feed gas is an important design consideration, and
> important characteristics of the feed gas include: moisture content,
> particulate content, oxygen concentration, temperature, pressure, and
> mass flow rate (AWWA/ASCE 1998). Pure oxygen is necessary for high
> efficiency ozone generators.
>
> *Wastes Generated:* The waste generated as a result of ozonation
> technology is the off-gas, which can have ozone concentrations as high
> as 0.5% by volume. Methods of disposing of off-gas include reinjection
> of off-gas ozone back into an upstream basin, decomposing via heating,
> chemical or catalytic reduction, and dilution (AWWA/ASCE, 1998).
> Catalytic reduction is a common method for ozone destruction,
> employing a rapid catalytic reaction and empty-bed contact times on
> the order of 1 minute (AWWA/ASCE, 1998). Ozone will react with many
> compounds in aqueous solution, and the health effects associated with
> these reaction products should be considered if the water will be used
> by the public following treatment. For example, when bromide is
> present in water, ozonation can generate bromate, a regulated
> disinfection byproduct. Bromate formation can be delayed by adding
> ammonia or reducing the pH of the water during ozonation. In addition,
> compounds formed by reaction with the contaminant may be of greater
> concern if there is the potential for formation of acutely toxic
> products.
>
> *Implementation and Flexibility:* Ozonation is used for both drinking
> water treatment and non-potable water treatment. Ozone gas is unstable
> and therefore needs to be produced onsite immediately prior to use.
> Furthermore, ozone rapidly decays in water and thus does not leave a
> residual disinfectant. Ozone generators are available from several
> suppliers as portable skid mounted units. To create ozone, air or
> oxygen is contacted with ultraviolet (UV) light or an electrical
> current, where some of the oxygen is converted to ozone. The resultant
> air stream is mixed with water in a large contacting vessel. The water
> is then degassed to remove the air/ excess ozone; the ozone in the
> exhaust air is destroyed prior to release to the atmosphere (Hammer,
> 1996). Ozonation consumes large amounts of electricity; in addition,
> operators need additional training to operate ozonation equipment.

-   **Reverse Osmosis (RO) and Nanofiltration (NF)** --- RO and NF are
    pressure-driven treatment processes using semi-permeable membranes
    that permit the diffusion of water through the membrane, but act as
    a selective barrier to contaminants. Water is forced through the
    membrane and contaminants are retained in a concentrated solution.

> *Effectiveness:* Both RO and NF are capable of removing dissolved
> organic and inorganic solutes, as well as pathogens such as viruses.
> The primary distinction between these two membrane separation
> processes is the ability of RO to effectively remove monovalent ionic
> species, such as sodium and chloride, compared with NF, which is not
> used in desalting applications. The effectiveness of RO and NF on
> individual compounds depends on the specific membrane selected as well
> as the contaminant. A principal concern for both RO and NF is membrane
> fouling by suspended solids and other contaminants, which should be
> removed by pretreatment such as filtration, adsorption, or pH control
> (Kirk-Othmer, 1997).
>
> *Residuals Generated:* RO and NF both generate a concentrated
> contaminant waste stream that needs to be treated and/or disposed of.
> RO produces a larger concentrate stream (typically between 25-50
> percent of the feed water flow) compared with NF (5 -- 25 percent of
> the feed water flow). Smaller quantities of chemical cleaning wastes
> are generated from periodic cleaning. In some cases, these residuals
> may be discharged to surface water or sewage systems, or injected into
> confined aquifers using deep wells. However, when used in response to
> a contamination incident, additional treatment of these residuals may
> be necessary since the process will concentrate the contaminants.
>
> *Implementation and Flexibility:* RO and NF are typically used to
> produce drinking water from brackish or salt water. The membranes are
> produced as standard-sized modules, which are commercially available
> from a number of vendors and compatible with standard pressure
> vessels. Unlike microfiltration and ultrafiltration, NF and RO modules
> are usually arranged in series to improve product water recovery. A
> set of NF/RO modules arranged in series is referred to as a membrane
> train. The capacity of a NF/RO system can be adjusted by varying the
> number of modules or membrane trains. Factors affecting efficiency and
> performance include type of solute, concentration, and pH. For
> example, neutral to alkaline pH can result in precipitation of
> inorganic scales on the membrane surface, which will reduce
> productivity. Therefore, RO and NF are almost always used in
> conjunction with pretreatment processes, such as filtration or
> chemical conditioning, to prevent membrane fouling (US EPA, 2003f,
> <http://www.epa.gov/safewater/lt2/guides.html>). Periodic backwashing
> or chemical cleaning is necessary to prevent or remove scaling or
> fouling.

-   **Ultraviolet (UV) Disinfection** -- UV disinfection is a process in
    which UV light is used to inactivate pathogenic microorganisms in
    water. Typically, low-pressure mercury arc lamps are used to produce
    the UV light, although medium pressure lamps are becoming more
    common. The water is brought into contact with UV light in a closed
    vessel reactor with very little contact time necessary (NDWC, 2000,
    <http://www.nesc.wvu.edu/ndwc/pdf/OT/TB/OT_TB_f00.pdf>).

> *Effectiveness:* UV disinfection typically deactivates microorganisms
> by damaging their DNA, which inhibits cellular function and can lead
> to their death. It can be effective against some, but not all,
> bacteria, virus, and protozoa. Unlike other disinfection technologies,
> UV disinfection is relatively insensitive to water temperature or pH.
> Turbidity and high concentrations of organic matter may reduce the
> effectiveness of this treatment. Lamp dosage can be adjusted for
> turbidity up to 10 NTU (US EPA, 2003g,
> <http://www.epa.gov/safewater/lt2/guides.html>). In addition,
> dissolved solids or salts may foul the lamp sleeve (US EPA, 2003g,
> <http://www.epa.gov/safewater/lt2/guides.html>).
>
> *Wastes Generated:* There are no wastes generated as a result of UV
> disinfection technology. However, the formation of disinfection
> byproducts during UV disinfection is currently being studied. The
> health effects associated with these byproducts should be considered
> if the water will be used by the public following treatment.
>
> *Implementation and Flexibility:* Some of the principal components of
> UV disinfection include a reactor with lamp, and power hookup.
> Typically, the components are housed in a building or similar
> structure. UV disinfection is available for a wide variety of water
> flow rates for small and large drinking water systems. Additionally,
> compact UV units are available for treating public water at customer
> sites (US EPA, 2003g, <http://www.epa.gov/safewater/lt2/guides.html>).
> One major advantage of UV light disinfection is that it is capable of
> disinfecting water flowing through the system at high rates. These
> rates depend on the design of the system, but can be faster than rates
> in chlorination systems. The technology has been used for disinfection
> of drinking water.

The technology is relatively simple to install and operate, requiring
minimum space and only minor ancillary equipment such as piping and
pumps. Temporary modular units are available for quick installation. UV
disinfection, however, has primarily been used at water plants, not
remediation sites, which may or may not be near a water treatment plant.

> Installations that use UV disinfection for drinking water are
> typically automated so that routine system adjustment and monitoring
> do not need close operator attention. During start-up, attention is
> needed to optimize performance. Safety issues during all phases of
> operation will include avoidance of UV light exposure, electrical
> safety, and the potential for release of mercury from broken lamps (US
> EPA, 2003g, <http://www.epa.gov/safewater/lt2/guides.html>).

### Alternatives for the Rehabilitation of System Components

Water system components include infrastructure and hardware used to
store, treat, and distribute water in the water system. In addition to
distribution system components, household plumbing, wastewater piping,
and sewer systems may need rehabilitation in a case of extensive
contamination. Remediation of the water system components will include
rehabilitation of the physical components (e.g., decontamination, repair
or replacement of water pipes, treatment equipment, or storage
equipment).

The performance, implementability, and cost-effectiveness of any
technology to rehabilitate water system components will be highly
contaminant- and system-specific. For example, treatment of an organic
chemical present in the water system below its solubility limit that
does not adsorb excessively to system components would require different
treatment than a contaminant that is strongly adsorbing. Based on public
health considerations, rehabilitation options for water systems include
the following:

-   **Disinfection of water system components** -- A few of the
    treatment/disinfection options presented in Section 4.1.2 of this
    module also would apply to the treatment/disinfection of water
    system components contaminated with microbial contaminants. The
    treatment options that would also apply to water system components
    include chlorination, chlorine dioxide, and other chemical
    disinfectants. To this end, AWWA standards (e.g., C651 through C654)
    are available for the disinfection of water system components
    including water mains, water storage facilities, water treatment
    plants, and wells. AWWA standards can be ordered at
    [http://www.awwa.org/bookstore/Category.cfm?cat=3](http://www.awwa.org/)
    (AWWA, 2004a).

-   **Flushing system** -- Flushing is performed by isolating sections
    of the distribution system and opening flushing valves (or more
    commonly fire hydrants) to allow a large volume of water to pass
    through the isolated pipeline. The objectives of flushing a system
    will vary depending on the nature of the contaminant. Flushing can
    be used to purge water containing dissolved or suspended
    contaminants from the system. It is necessary to plan the operation
    so that it is done at the location of maximum contaminant
    concentration, so that it does not worsen the situation by spreading
    the contaminant further in the system. Flushing also may be used to
    remove contaminants that are adhering to the interior pipe walls. In
    this case, it will be necessary to plan the operation to close
    valves and open hydrants in a way that produces sufficient scour
    velocities and/or flow reversal. Depending on the contaminant(s),
    the use of chemical cleaning agents also may be appropriate.
    Environmental concerns associated with flushing include discharge of
    water containing the contaminant, followed at some length by any
    disinfectant residual, and finally by any suspended solids. See
    Section 5.3 of this module regarding pretreatment or direct
    discharge options for the management of this water.

-   **Pigging, swabbing, mechanical cleaning, and chemical cleaning of
    system piping** -- Pigging and swabbing are pipe-cleaning techniques
    that use bullet-shaped pieces of polyurethane to clean water
    distribution pipes. The \"pigs\" are propelled by water pressure and
    mechanically scrape heavy sediment, biofilm, adherent material,
    tuberculation, and even very hard scale debris and deposits from the
    inside of the pipe. Pigging and swabbing provide effective means to
    clean system components and improve hydraulic flow. If a contaminant
    has adsorbed onto deposits on the pipe walls, then pigging or
    swabbing may be an effective rehabilitation strategy.

-   **Air scouring system components** - Air scouring is a useful
    rehabilitation option where system pressures are too low or
    pipelines are too large for effective flushing. Air scouring is used
    to remove soft scales, biofilm, or other adherent materials. Air
    scouring is performed by isolating a section of the water
    distribution system, injecting compressed air into the line, and
    collecting the air/water mixture exiting the line. The collected
    water contains sediments and other contaminants present in the pipe.

-   **Sandblasting system components** -- Sandblasting is a cleaning
    technique for system components, most applicable for water storage
    facilities such as tanks. A variety of blast media of varying
    aggressiveness (e.g., sodium bicarbonate, sand) are available for
    blasting operations. Blasting removes most accumulated contaminants,
    sediments, soft scales, biofilm or other impurities that have been
    deposited on the surface.

-   **Relining system components, including piping** -- Lining system
    components and piping is a cost-effective method of rehabilitating
    water system infrastructure in comparison to replacement, assuming
    that long-term remediation goals can be met by relining. Lining is
    generally conducted using cement although other materials, such as
    epoxy resins, are available. The process involves coating the inside
    of pipes in-place. It is also a very simple matter to coat pressure
    vessels and other components by brush or spray application. AWWA
    standards are available for lining operations (e.g., AWWA Standard
    "C205-00: Cement-Mortar Protective Lining and Coating for Steel
    Water Pipe---4 In. (100 mm) and Larger"). AWWA standards are
    available for purchase at
    [http://www.awwa.org/bookstore/Category.cfm?cat=3](http://www.awwa.org/)
    (AWWA, 2004a). Materials used for lining components should be
    approved by the National Sanitation Foundation as acceptable lining
    medium for potable water applications. The benefits of pipe lining
    include: increased water quality; one-third to one-half of typical
    pipe replacement costs; increased protection for cast iron, steel,
    concrete and asbestos cement pipes from corrosion and abrasion
    caused by aggressive water chemistry; enhanced hydraulic capacity;
    and prevention of the release of contaminants such as iron into the
    distribution system, which can cause red water.

> While cement is commonly used, epoxy is also a good material for
> relining for the following reasons: Once epoxy hardens, it is very
> stable and inert for domestic water; epoxy has a tenacious bond to
> metals; although epoxy is considered brittle compared to other
> plastics, it is far less brittle than the alternatives used for tank
> coating, such as glass, fiberglass, concrete, etc; epoxy has a good
> tensile and shear strength, making it a tough, resilient material; and
> epoxy has predictable physical properties (viscosity, cure time,
> etc.).

-   **Repairing and replacing physically damaged water distribution
    pipes** -- Water mains that have been physically damaged (although
    not contaminated) may need to be replaced. Replacement of broken
    pipe typically involves excavation. For structurally damaged pipe
    (without contamination), a repair sleeve may be installed on the
    outside of the broken pipe section and clamped into place. Following
    pipe repair, the line is flushed with water to remove sediment and
    disinfected with a high concentration chlorine solution.
    Disadvantages of pipe replacement include high labor needs, erosion
    and sedimentation resulting from excavation, and generation of water
    from flushing. See Section 5.3 of this module regarding management
    practices for wastes generated from replacement operations.

-   **Condemning and replacing affected portion of system or affected
    system components** -- During the contamination incident, the
    response personnel may have been able to isolate the contaminated
    water to a specific portion of the water distribution system through
    the use of selected valves. A determination may be made that the
    contaminated portion of the water distribution system is beyond
    rehabilitation and repair and should be condemned, removed, and
    replaced.

-   **Utilizing current water source with new water distribution
    system** -- A determination may be made that the water distribution
    system is beyond rehabilitation due to irreversible contamination or
    significant physical damage to major system components, in which
    case it may need to be removed and replaced. If the water source is
    treatable or uncontaminated, then the water utility and responsible
    agency may decide to utilize the current water supply but construct
    a new distribution system.

-   **Utilizing current water distribution system with new water
    source** -- A determination may be made that the water distribution
    system may be rehabilitated but that the water source cannot be
    recovered or remediated. A permanent alternate water source will be
    needed, and the water utility and responsible agency may decide to
    connect the permanent alternate water source to the existing water
    distribution system. Some options for an alternate water source may
    include neighboring municipal systems, ground water sources, or a
    different water source or intake, such as a nearby lake or river.

-   **Condemning and replacing entire water system** -- A determination
    may be made that the entire water system is beyond rehabilitation
    due to irreversible contamination or significant physical damage to
    major system components. A new water distribution system will need
    to be constructed and an alternate water source selected. The water
    utility should implement design and construction procedures for the
    necessary water source and distribution components. These procedures
    will employ design engineers, construction contractors, and the
    involvement of the necessary local and state officials. Depending on
    the situation and the severity of the contamination event, the USACE
    may also be involved. Most states require the approval of plans and
    specifications for public water supply facilities before
    construction begins. System additions, major alterations, and new
    installations come under this provision. The water utility will need
    to continue communicating with the public on the rehabilitation
    efforts and decisions to develop a permanent alternate water supply
    source and water distribution system (see Section 7 of this module).

### Alternatives for Affected Environmental Media

Contaminants introduced into a water system can also result in
contamination of environmental media such as sediments, soil,
vegetation, air, and biota. Contamination could occur due to
partitioning of a chemical from the water phase to the soil, sediment,
or air, or could occur via a direct spill of the contaminant onto soil,
sediment, vegetation or biota. A substantial body of information on the
remediation of contaminated environmental media has been developed
primarily in support of Superfund cleanups, Resource Conservation and
Recovery Act (RCRA) corrective action, military base realignment and
closure, and the Brownfields initiative. US EPA's Technology Innovation
Program is a good starting point for information on remediation of
contaminated environmental media (US EPA, undated b,
<http://clu-in.org/>).

### Additional Resources

Additional information on remedial technologies and strategies can be
found on EPA's and AWWA's web sites:

-   US EPA's Technology Innovation Program web site contains links to
    remediation technology resources at
    <http://www.epa.gov/tio/remed.htm> (US EPA, 2004d);

```{=html}
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```
-   US EPA information on verified treatment technologies can be found
    at Environmental Technology Verification Program web site at
    <http://www.epa.gov/etv/> (US EPA, 2004e);

-   Additional water remediation resources can be found at
    <http://www.epa.gov/ebtpages/watewaterpremediation.html> (US EPA,
    2004f); and

-   AWWA publishes books that address water and system quality that are
    available at
    [www.awwa.org/bookstore/](http://www.awwa.org/bookstore/) (AWWA,
    2004b).

## Remedy Evaluation Criteria

Once a list of potential remedial response actions is developed,
evaluation of these potential actions should begin. The first step in
this analysis is to eliminate actions that are not "implementable" or
reasonable for the situation. Actions that pass through this screening
step are evaluated in progressively greater detail. For a small system
with only one contaminant in one media (e.g., water) and few system
components, this evaluation process could be quite simple. For a larger
system with multiple contaminants in water, sediments, and equipment,
the evaluation could be quite complex and involve an iterative analysis
where options are investigated multiple times in ever-greater detail.

The criteria for evaluating different actions include:

-   **Overall Protection of Human Health and the Environment** -- Under
    this criterion, the evaluation must describe how the alternative
    achieves and maintains protection of human health and the
    environment. Assessments of human health and environmental
    protection are related to other evaluation criteria, especially
    long-term effectiveness and permanence, short-term effectiveness,
    and compliance with applicable regulations. Evaluation of the
    overall protectiveness of an alternative should focus on whether a
    specific alternative achieves adequate protection and should
    describe how risks posed through each exposure pathway are
    eliminated, reduced, or controlled through treatment, engineering,
    or institutional controls. This evaluation also allows for
    consideration of any unacceptable short-term or cross-media impacts
    of an alternative.

-   **Compliance with Applicable Regulations** -- Under this criterion,
    the evaluation must describe how the alternative complies with
    applicable regulations, in particular those related to water.
    Regulatory requirements can be numerous and can include
    contaminant-based requirements (e.g., MCLs), location-specific
    requirements (e.g., preservation of historic sites), and
    action-specific requirements (e.g., for RCRA waste classification).

-   **Long-term Effectiveness and Permanence** -- Under this criterion,
    the evaluation must describe how the alternative provides long-term
    effectiveness in maintaining protection of human health and the
    environment after response objectives have been met. This factor
    assesses the residual risk remaining from untreated waste or
    treatment residuals at the conclusion of remedial activities and
    assesses the adequacy and suitability of controls, if any, that are
    used to manage treatment residuals or untreated wastes that remain
    at the site.

-   **Reduction of Toxicity/Infectivity and Mobility Through Treatment**
    -- The assessment against this criterion evaluates the reduction of
    toxicity (or infectivity for pathogens) and contaminant mobility in
    the water. Treatment processes with the highest reduction of
    toxicity/infectivity and contaminant mobility rank the highest under
    this criterion. This evaluation focuses on the remedy employed, the
    materials being treated, and the expected reduction in
    toxicity/infectivity and/or mobility.

-   **Generation of Residuals** -- This criterion involves assessment of
    the types of air, water, or solid waste impacts resulting from a
    treatment alternative. Optimally, no treatment residuals will be
    generated. Examples of treatment residuals for water remediation
    include spent filter media, regenerant solutions, and off-gas from
    air strippers. Examples of treatment residuals for water
    distribution include runoff, flushing solution, and discarded pipe.
    Treatment residuals may often contain the contaminant of concern.
    The type, volume, and ease of management of treatment residuals will
    affect how alternatives are ranked against this criterion.

-   **Short-term Effectiveness** -- Under this criterion, the assessment
    examines the short-term effectiveness of alternatives in protecting
    human health and the environment during the construction and
    implementation of a remedy until remediation objectives have been
    met. Consideration should be given to risks that result from
    implementation of the proposed remedial action and how these risks
    may impact the community, workers, and the environment. Risks could
    be generated, for example, from dust from excavation or from air
    emissions from stripping towers.

-   **Implementability** -- This assessment evaluates the technical and
    administrative feasibility of alternatives and the availability of
    necessary goods and services. This includes consideration of
    technical difficulties and unknowns with construction and operation
    of the technology, reliability of the technology, the ability to
    monitor the effectiveness of the remedy, the need to coordinate with
    other offices or agencies (e.g., to obtain permits), availability of
    adequate hazardous waste treatment (if needed), storage and disposal
    services (if needed), availability of necessary equipment and
    specialists, availability of service and materials, and the
    commercial availability of the prospective technologies.

-   **Cost** -- This assessment evaluates the capital and O&M costs of
    each alternative. The level of detail needed to analyze each
    alternative against these evaluation criteria will depend on the
    type and complexity of the site, the technologies and alternatives
    being considered, and other project-specific considerations. The
    analysis should be conducted in sufficient detail so that
    decision-makers understand the significant aspects of each
    alternative and any uncertainties associated with the evaluation
    (e.g., a cost estimate developed on the basis of a volume of media
    that could not be defined precisely).

-   **State (Support Agency) Acceptance** -- This assessment reflects
    the state\'s (or support agency\'s) apparent preferences for various
    alternatives, or concerns.

-   **Community Acceptance** -- This assessment reflects the
    community\'s apparent preferences for various alternatives, or
    concerns.

## Comparative Analysis of Alternatives and Remedy Selection

Once the alternatives have been described and individually assessed
against the criteria, a comparative analysis should be conducted to
evaluate the relative performance of each alternative relative to one
another and relative to each criterion. The purpose of this comparative
analysis is to identify the advantages and disadvantages of each
alternative relative to one another so that the key tradeoffs can be
identified. Overall protection of human health and the environment and
compliance with applicable regulations will generally serve as threshold
determinations in that they should be met by any alternative. Criteria
such as long-term effectiveness and permanence, reduction of
toxicity/infectivity and mobility through treatment, short-term
effectiveness, implementability, and cost generally will need more
consideration because the major tradeoffs among alternatives will most
frequently relate to one or more of these.

The comparative analysis may be presented in a tabular, bulleted, or
narrative format. For a complex system contamination incident, a tabular
format may be preferred (see examples in US EPA, 1988a,
<http://www.epa.gov/superfund/action/guidance/remedy/rifs/overview.htm>)
where each alternative can be evaluated against each criterion in a
side-by-side format.

The results of these analyses should be documented in a Remedy Selection
Study report to present a comparative analysis of remedial alternatives.
The lead agency will work in partnership with the water utility, State
and local government, and affected parties to evaluate remedial options
and select the remedy that will satisfy the remedial action objectives.

# Remedial Design, Remedial Action, and Post-Remediation Monitoring and Operations

## Remedial Design

After a final remedy is selected, the remedial design is developed. The
remedial design is a series of documents, specifications, and drawings
that detail the steps to be taken during the remedial action. The lead
agency will be responsible for remedial design, assisted by the water
utility and other technical support staff.

The Remedial Design Work Plan should include the following components:

-   Statement of remedial design goals;

-   Description of each task and deliverable;

-   Project schedule identifying task and deliverable completion dates;

-   Proposed strategy for contracting the Remedial Action;

-   Proposed personnel;

-   Areas requiring clarification or anticipated problems;

-   Proposed use of subcontractors and how their efforts will be
    managed;

-   Detailed cost proposal;

-   A listing of all drawings and specifications that will be prepared;
    and

-   Conflict of interest statement.

Additional sampling may be needed to obtain data to support the design
effort. If on-site sampling is needed as part of the design effort, then
a site data collection plan (discussed in Section 3.2.1 of this module)
should be developed that addresses site security, health and safety,
sampling and analysis procedures, and QA.

The remedial design is an engineering phase in which detailed technical
plans are developed for the selected remedy. The remedial design will
include specifications for the treatment/containment system, which will
need to consider a host of factors including:

-   Duration of cleanup;

-   Remediation goals;

-   Total volume of water to be treated;

-   Design criteria (concentrations, contact time, etc.);

-   Regulatory issues;

-   Availability of specialized personnel from US EPA or contractors;
    and

-   Mobilization time (i.e., consideration of the available treatment
    equipment/supplies and the time it will take to get them in place).

Note that some of these same factors were considered during the remedy
selection phase.

The remedial design documentation might include the building and
operation of the remedial system and verification that the contamination
has been sufficiently reduced or eliminated. For a more extensive
remedial action the following documents might be included:

-   **Design Criteria Report** -- The design criteria report describes
    the technical parameters upon which the design is based. The report
    will contain a project description, design parameters and provisions
    (e.g., waste characterization), and O&M provisions that will
    influence the design approach.

-   **Basis of Design Report** -- The basis of design report is a
    detailed description of the analyses that are conducted to select
    the design approach. The report will include a detailed
    justification of design assumptions, a remedial action contracting
    strategy that will specify qualifications of the contractor, a
    permitting plan that details how permitting requirements needed to
    remediate the site will be met, and identification of easement and
    access needs.

-   **Specifications** -- These specifications will include
    construction, installation, site preparation, and fieldwork
    standards, including particular needs for operator training. The
    specifications should also include a register of all plans,
    documents, etc. to be submitted during the remedial action.

-   **Drawings and Schematics** -- Drawings and schematics may include
    process flow diagrams, piping and instrumentation diagrams, grading
    and drainage controls, a vicinity map, and others.

-   **Construction Quality Assurance Plan** -- The Construction Quality
    Assurance Plan describes the QA tests necessary to ensure that the
    final product meets the design specifications.

-   **Draft Operation and Maintenance (O&M) Manual** -- The designer
    prepares a draft of the O&M manual. The manual will include
    descriptions of the following: normal O&M, description of potential
    operating problems, QA plan for O&M, safety plan, listing of
    installed equipment, recording and reporting procedures, and O&M
    cost estimate.

-   **Remedial Action Solicitation Package** -- This package will
    include the remedial action statement of work, solicitation/contact
    form, prices for supplies and services, terms and conditions of the
    contract, method of procurement, prevailing wage rates
    determination, deadline and location for submitting bids, and all
    appropriate contact clauses.

-   **Remedial Action Schedule** -- The schedule will detail specific
    remedial action milestones and outline estimated completion dates.
    The schedule will include the estimated labor, equipment, and
    oversight resources to complete each milestone.

-   **Remedial Action Cost Estimate** -- The cost estimate will include
    all costs necessary to arrive at the current estimate. This estimate
    should be as detailed as the design documents allow. Vendor
    quotations should be included in the cost estimate when used.

## Remedial Action

The remedial action consists of executing the remedy according to the
remedial design and preparing the water distribution system for
long-term monitoring and maintenance, if necessary. Remediation of the
contaminated water might occur concurrently with rehabilitation of
system components. If the remedial action includes natural attenuation
as a component, then provisions for long-term monitoring and maintenance
should be made. The performing organization will prepare a Remedial
Action Work Plan that will include the following:

-   Roles and responsibilities of the construction management team and
    other key personnel;

-   Remedial action schedule;

-   Method of implementing construction quality assurance plan;

-   Health and safety plan for all field activities;

-   Identification of major equipment needs; and

-   Description of testing and inspection procedures for determining
    constructor compliance with remedial action objectives.

Remedial action activities should be documented in a Remedial Action
Report (or series of reports if needed) to document all remedial
response actions taken and the basis for determining that the
remediation goals were (or were not) attained.

## Disposal of Remediation Residuals 

Field activities that are conducted to remediate the water system will
result in the generation of decontamination residuals and remediation
wastes. These residuals and wastes could include, for example:

-   Contaminated surface water or ground water;

-   Decontamination fluids (e.g., acids, solvents, detergents, wash
    water);

-   Water treatment residuals (e.g., biosolids, filter cake, spent
    filter media);

-   Contaminated soil or sediments generated from cleanup of a
    contaminated surface water supply;

-   Contaminated consumer equipment (home filters, ice makers, soda
    dispensers, water heaters, and garden hoses); and

-   Personal protective equipment.

The agency responsible for management of these wastes (as designated by
the Incident Commander) must identify applicable regulations and
determine how to properly manage the wastes in accordance with those
regulations.

### Applicable Regulations

Wastes generated from water system remediation and recovery activities
may contain contaminants that cause the wastes to be subject to Federal,
State, or local regulations. For example, a waste may contain hazardous
constituents that cause it to be regulated under RCRA or other
regulations such as the Clean Water Act (CWA) or the Toxic Substances
Control Act (TSCA). Note that the US EPA does not regulate etiological
(disease-causing) wastes except in a few specific cases such as the
operation of medical waste incinerators. States, however, may have
regulations concerning etiological wastes.

[Resource Conservation and Recovery Act (RCRA)]{.underline}

RCRA was passed to protect human health and the environment, to conserve
energy and natural resources, and to reduce the generation of hazardous
wastes. RCRA has ten discrete sections (Subtitles) that address specific
waste management activities. Two of these Subtitles and their
implementing regulations are applicable to remediation and recovery of
contaminated water supply systems: Subtitle C (Hazardous Waste
Management) and Subtitle D (Solid Waste Management). The RCRA Hazardous
and Solid Waste Amendments (HSWA) of 1984 established land disposal
restrictions (LDR) for RCRA hazardous wastes and mixtures of RCRA
hazardous wastes with other substances. Under the RCRA LDR regulations,
restricted RCRA wastes may only be land disposed after treatment using
specified technologies or treatment to meet specified concentration
limits.

Under RCRA, wastes generated from remediation and recovery activities at
contaminated water supply systems will need to be characterized as
either hazardous or non-hazardous. Therefore, the agency designated with
this responsibility by the Incident Commander must characterize and
classify the waste at its point of generation. Solid wastes -- such as
excavated soils and spent filter media -- must be classified as either
nonhazardous waste (under RCRA Subtitle D) or hazardous waste (under
RCRA Subtitle C). Liquid wastes -- such as decontamination fluids --
also must be so classified. Environmental media, such as soils, are
subject to RCRA Subtitle C only if they are "generated" (i.e.,
excavated) and contain listed hazardous waste or exhibit a
characteristic of hazardous waste (US EPA, 1998c,
[http://www.epa.gov/epaoswer/hazwaste/ca/resource/guidance/remwaste/pspd_mem.pdf](http://www.epa.gov/cgi-bin/claritgw?op-Display&document=clserv:OSWER:0579;&rank=4&template=epa)).
Waste waters and liquid wastes, such as contaminated surface water or
ground water, must either be handled as a hazardous waste, be discharged
to a receiving water if it is determined not to contain any hazardous
wastes, or be discharged to a publicly owned treatment works (POTW). The
latter two options are subject to the requirements of the CWA (see
below), including the pretreatment standards for discharge to a POTW.

For more information on classifying solid wastes, see US EPA's RCRA,
Superfund & Emergency Planning Community Right-to-Know Act (EPCRA) Call
Center Training Module on *Hazardous Waste Identification* at
<http://www.epa.gov/epaoswer/hotline/training/hwid.pdf> (US EPA, 2003h)
or the *Land Disposal Restrictions Summary of Requirements* at
<http://www.epa.gov/epaoswer/hazwaste/ldr/ldr-sum.pdf> (US EPA, 2001d).
Because of the complexity of these determinations, it is strongly
advised that appropriate expertise be sought. If the FRP has been
activated, then US EPA may take responsibility for making this
determination.

The following guidance documents are relevant to the classification and
disposal of solid wastes generated as part of the remediation
activities:

-   *Management of Investigation-Derived Wastes* (US EPA, 1992b);

-   *RCRA Waste Sampling Draft Technical Guidance* (US EPA, 2002e,
    <http://www.epa.gov/epaoswer/hazwaste/test/samp_guid.htm>); and

-   *Land Disposal Restrictions: Summary of Requirements* (US EPA,
    2001d, <http://www.epa.gov/epaoswer/hazwaste/ldr/ldr-sum.pdf>).

Treatment, storage, or disposal of hazardous waste is closely regulated;
however, generators of hazardous waste are allowed to accumulate
hazardous waste at the site of generation in tanks, containers, drip
pads or containment buildings for up to 90 days without a RCRA permit.
These allowances should be considered during remedy selection and design
because they will facilitate rapid cleanup. Accumulation units must meet
applicable design, operating, closure, and post-closure standards. The
exemption for 90-day accumulation is found in regulations at 40 CFR
262.34; the associated preamble discussion is at 51 FR at 10168 (March
24, 1986).

Additionally, the agency designated with responsibility for managing
remediation residuals by the Incident Commander may be able to apply the
following permit waivers and emergency situation exemptions during
remediation and recovery activities for a contamination incident.

-   **Temporary Emergency Permits and Authorized Activities** -- In the
    event of an imminent and substantial endangerment to human health or
    the environment (such as an intentional drinking water contamination
    incident), US EPA or a RCRA- authorized state may issue a temporary
    emergency permit for treatment, storage or disposal of hazardous
    waste. Emergency permits may allow treatment, storage or disposal of
    hazardous waste at a non-permitted facility or at a permitted
    facility for waste not covered by the permit. Emergency permits must
    be accompanied by a public notice that meets the requirements of 40
    CFR 124.10(b), including the name and address of the office
    approving the emergency permit, the name and location of the
    hazardous waste treatment, storage or disposal facility, a brief
    description of the wastes involved, the actions authorized and the
    reason for the authorization, and the duration of the emergency
    permit.

> Under regulations in 40 CFR 270.42(e), US EPA or a RCRA-authorized
> state may temporarily authorize a permittee for an activity that would
> be the subject of a Class 2 or Class 3 permit modification in order
> to, among other things, facilitate timely implementation of closure or
> corrective action activities. (Information on which states are
> authorized to implement RCRA is provided at US EPA, 2004g,
> <http://www.epa.gov/epaoswer/hazwaste/state/index.htm>.) Activities
> approved using a temporary authorization must comply with applicable
> requirements of 40 CFR Part 264. Temporary authorizations are limited
> to 180 days, with an opportunity for an extension of 180 additional
> days. To obtain an extension of a temporary authorization, a permittee
> must have requested a Class 2 or 3 permit modification for the
> activity covered in the temporary authorization. Public notification
> of temporary authorizations is accomplished by the permittee sending a
> notice about the temporary authorization to all persons on the
> facility mailing list and to appropriate state and local governments.
> (See the regulations at 40 CFR 270.42, promulgated on September 28,
> 1988, and the associated preamble at 53 FR 37919.)

-   **Exemptions for Emergency Situations** -- Regulations in 40 CFR
    264.1(g)(8) provide that people engaged in treatment or containment
    activities are not subject to the requirements of 40 CFR Part 264 if
    the activities are carried out during immediate response to: (1) a
    discharge of hazardous waste; (2) an imminent and substantial threat
    of a discharge of hazardous waste; (3) a discharge of a material
    which, when discharged, becomes a hazardous waste; or, (4) an
    immediate threat to human health, public safety, property or the
    environment from the known or suspected presence of military
    munitions, other explosive material, or an explosive device. This
    means that, under 40 CFR 264.1(g)(8), during the immediate phase of
    an incident response, hazardous waste management activities do not
    require hazardous waste permits. Hazardous waste management units
    used during immediate response actions are not subject to RCRA
    design, operating, closure or post-closure requirements. Of course,
    if hazardous waste treatment activities or other hazardous waste
    management activities continue after the immediate phase of an
    incident response is over, then all applicable hazardous waste
    management and permitting requirements would apply. In addition, if
    an incident occurs at a facility that is already regulated under 40
    CFR Part 264, then the facility owner/operator must continue to
    comply with all applicable requirements of 40 CFR Part 264 Subparts
    C (preparedness and prevention) and D (*contingency plan* and
    emergency procedures).

[Clean Water Act (CWA)]{.underline}

The CWA addresses site-specific pollutant discharge limitations and
performance standards for specified industries to protect surface water
quality. Remediation and recovery activities at contaminated water
supply systems may involve direct discharges of contaminated water or
treated water. Direct discharge of contaminated water or treated water
to surface waters is regulated under the CWA.

Discharge of contaminated water to a POTW is also regulated under the
CWA. For water discharged to a POTW, the agency designated with this
responsibility by the Incident Commander must ensure that the wastewater
meets the pretreatment standards as established by the CWA at 40 CFR
403. 40 CFR 403 provides the regulatory basis to require non-domestic
dischargers to comply with pretreatment standards (effluent limitations)
to ensure that the goals of the CWA are attained. The national
pretreatment program, under the CWA, requires an analysis to determine
whether the water discharged may pass through the POTW without causing
water quality problems for the receiving streams or interfering with the
POTW operations. Additional discussion on releases to POTWs may be found
in Section 5.3.2 of this module.

[Toxic Substances Control Act (TSCA)]{.underline}

TSCA requires that RCRA non-hazardous remediation waste containing PCBs
or asbestos to be disposed of at facilities regulated under TSCA, in
certain circumstances. Regulations governing the management of wastes
containing PCBs are found at 40 CFR 761.60.

### Types of Waste and Management Options

The sections below discuss management options for the various types of
waste that may be generated during remediation and recovery of a
contaminated water system.

[Contaminated Water]{.underline}

In responding to an intentional water contamination incident, the
contaminated water supply and water in the distribution system may be
pumped from the system, possibly treated, and ultimately may need to be
disposed of accordingly. The contaminated water may also migrate to
nearby surface or ground waters. If the contamination event affects one
or more drinking water supply wells, then the remedial action could
involve the generation of contaminated water drawn from the affected
well(s) during pump and treat operations.

Contaminated wastewaters also may be generated from the following
activities:

-   Firefighting;

-   Disposal of contaminated water from industry;

-   Disposal of contaminated water from consumers; and

-   Disposal of contaminated water from bulk storage areas (farms,
    hospitals, universities, etc.).

It must be determined whether the contaminated waters and treated
waters:

-   Are considered hazardous waste;

-   May be discharged directly to a surface water (e.g., lake or
    stream);

-   May be discharged to a POTW; or

-   May be injected into the ground.

If the contaminated water is not considered to be hazardous and
contaminant concentrations are below an acceptable threshold, then a
determination may be made that it is acceptable to discharge the
contaminated waters to a nearby water source, subject to the
requirements of the CWA. If the contaminated waters and treated waters
are considered hazardous wastes, then they will need to be appropriately
disposed of, either at an off-site facility or through discharge to a
POTW. Underground injection may also be an option under certain
circumstances. Discharge to a POTW and underground injection are
discussed in further detail below.

-   **Discharge to a POTW** -- RCRA hazardous wastewater can be disposed
    of at a POTW that has appropriate RCRA permits and that meets the
    off-site policy criteria for a facility receiving hazardous waste.
    Disposal at a POTW of nonhazardous wastewaters also is an option if
    the POTW is equipped to handle the discharge. In either case, as
    discussed above, non-domestic discharges must comply with
    pretreatment standards. Under the national pretreatment program, if
    water is to be discharged to a POTW, then the following should be
    evaluated:

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-   The quantity and quality of the wastewater and its compatibility
    with the POTW. (The constituents in the wastewater must not cause
    pass-through or interference, including unacceptable sludge
    contamination or a hazard to POTW employees; pretreatment of the
    contaminated water prior to discharge to the POTW may make the
    contaminated water more compatible with the POTW).

-   The ability of the POTW to ensure compliance with applicable
    pretreatment standards and requirements, including monitoring and
    reporting requirements.

-   The POTW's record of compliance with its National Pollutant
    Discharge Elimination System (NPDES) permit and pretreatment program
    requirements to determine if the POTW is a suitable disposal site
    for the contaminated water.

-   The potential impact on air quality.

-   The potential for ground water contamination from transport of the
    contaminated water or impoundment at the POTW.

-   The potential effect of the contaminated water on the POTW's
    discharge as evaluated by maintenance of water quality standards in
    the POTW's receiving waters.

If the contaminated water does not meet the pretreatment standards, then
toxic pollutants may pass through the treatment plant into the receiving
waters, posing serious threats to aquatic life, to human recreation, to
consumption of fish and shellfish, and to human health if downstream
drinking water systems use the water as a source. Pass-through can make
waters unswimmable or unfishable, not meeting the goals of the CWA.
These discharges also can interfere with the biological activity of the
treatment plant causing sewage to pass through the treatment plant
untreated or inadequately treated.

Discharge of decontamination wastewater to the sewer system will present
a POTW with a number of challenges that will need to be addressed and
coordinated with the POTW operator. The most immediate and critical
concerns will involve the following:

-   Treatment plant employee safety;

-   Preservation of biological treatment processes at the plant;

-   Protection of receiving waters; and

-   Protection of biosolids quality.

> There is ongoing research into the types of contaminants which POTWs
> may need to plan for during a contamination incident, the fate and
> transport of contaminants in the collection and treatment systems, and
> the appropriate worker safety precautions to take for a particular
> contaminant. The Association of Metropolitan Sewerage Agencies (AMSA)
> is working on a Wastewater Utility Planning Tool that will serve as a
> critical planning resource for POTWs in preparation for a
> contamination event. The Planning Tool will help POTWs make informed
> decisions by identifying the issues they should consider in their
> decision-making process and by directing them to existing and evolving
> resources and research to support those decisions. The Planning Tool
> should provide a generic protocol for handling decontamination
> wastewaters that could be customized, or tailored, to be
> contaminant-specific. For more information on this tool, visit AMSA at
> <http://www.amsa-cleanwater.org/> (AMSA, undated).

-   **Injection of Wastewater** -- A decision may be made by the agency
    designated by the Incident Commander with responsibility for
    managing decontamination residuals to inject the treated and/or
    contaminated wastewaters into the ground. Such an action would be
    subject to the Underground Injection Control Program under the SDWA.
    The Underground Injection Control Program establishes five classes
    of injection wells:

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-   Class I: wells used to inject hazardous, industrial, municipal, or
    radioactive waste [beneath]{.underline} the lowermost formation
    containing an underground source of drinking water.

-   Class II: wells used to inject fluids associated with oil and
    natural gas production.

-   Class III: wells used to inject fluids into formations in order to
    extract minerals.

-   Class IV: wells used to inject hazardous or radioactive waste [into
    or above]{.underline} a formation containing an underground source
    of drinking water.

-   Class V: wells that are not included in Classes I through IV

    Wells used for injecting decontamination residuals would fall within
    Class I, IV, or V. Class I wells are subject to permitting, design,
    and operating requirements under the Underground Injection Control
    Program and, additionally, are regulated under RCRA if used to
    inject hazardous waste. Class IV wells are banned except in
    connection with certain remediation activities as defined under RCRA
    Section 3020(b). Decontamination residuals from remediation of a
    contaminated water system would not be expected to fall within the
    RCRA Section 3020(b) exemption. Additional information on the
    Underground Injection Control Program can be found at:
    <http://www.epa.gov/safewater/uic.html> (US EPA, 2004k).

[Other Wastes Generated On Site]{.underline}

During a drinking water system contamination incident or the subsequent
remediation and recovery, a wide variety of other wastes could be
generated. These wastes could include the following:

-   Soils surrounding the water supply (i.e., surface water supply) and
    sediments in the reservoir that become contaminated due to migration
    of the contaminant from water into sediments;

-   Decontamination fluids including acids, solvents, detergents, and
    wash waters;

-   Water treatment residuals such as biosolids, filter cake and/or
    sludge generated from the treatment and rehabilitation of the water
    supply and water distribution system

-   Spent filter media such as sand and GAC generated from the treatment
    and rehabilitation of the water supply and water distribution
    system; and

-   Personal protective equipment, such as Tyvek® suits, rubber gloves,
    tape, respirator cartridges, etc., used by response action
    personnel.

Each of these wastes will need to be properly classified and their
treatment and disposal options considered. Contaminated environmental
media such as remediation and recovery waste materials are not, in
themselves, hazardous waste and generally are not subject to regulation
under RCRA subtitle C. However, contaminated environmental media can
become subject to regulation under RCRA if they "contain" hazardous
waste. US EPA generally considers contaminated environmental media to
contain hazardous waste:

1.  When the media exhibits a characteristic of hazardous waste.

2.  When the media is contaminated with concentrations of hazardous
    constituents above specified levels as indicated by the toxicity
    characteristic leaching procedure (TCLP). The listing of hazardous
    constituents and the TCLP levels are provided in 40 CFR 261.24.

3.  When the media contains a listed hazardous waste. Hazardous waste
    listings are provided in 40 CFR 261.

[Wastes Generated Off Site]{.underline}

Wastes from off site may need to be addressed as well. Essentially
anything contacting the contaminated water may become a waste requiring
disposal. Contaminated equipment may include (but not be limited to)
water treatment and filter devices (either installed at the faucet or on
the main water line inside the building or house), coffee makers,
icemakers, water heaters, garden hoses, sprinklers, toilets, spas, and
swimming pools. The agency designated with this responsibility by the
Incident Commander may need to provide notification to businesses and
consumers advising them of equipment that may have become contaminated
during the incident and what they should or should not do. The agency
designated with this responsibility by the Incident Commander may decide
to have a central location to collect the contaminated equipment and
handle and dispose of the material accordingly.

## Post-Remediation Monitoring

Before the remedial action can be terminated, it will be necessary to
verify that the remedial objectives have been attained. This will
necessitate quantitative verification that the contaminant concentration
has been reduced to acceptable levels, through methods specified by the
lead agency. For an example methodology, see *Methods for Evaluating the
Attainment of Cleanup Standards* [(US EPA, various dates,
http://www.epa.gov/tio/char1_edu.htm#stat_samp](http://www.epa.gov/tio/char1_edu.htm#stat_samp)),
which provides guidance on statistical methods for verifying attainment
of cleanup standards.

After the water system is returned to normal operations, the water
utility and potentially the primacy agency and/or health department will
likely assume responsibility for the continued monitoring of the system
for the contaminants of concern to provide long-term assurance that the
system can maintain normal operation. These monitoring activities may
include:

-   Monitoring for the contaminants of concern;

-   Periodic inspection and maintenance of the treatment equipment
    remaining on site;

-   Periodic inspection and maintenance of the water distribution system
    components;

-   Maintenance of security measures or institutional controls; and

-   Public communication of monitoring activities and results.

A post-remediation monitoring program will be necessary to ensure
continued compliance with the remediation objectives. These activities
should be documented in a post-remediation monitoring plan developed
using an approach described in Section 3.2.1. The primacy agency and/or
health department will be responsible for identifying sampling
locations, frequency, parameters, and duration. The water utility may be
responsible for conducting the sampling and monitoring, reporting the
results, and keeping the public informed. The sampling and monitoring
methods to be employed will depend on site-specific conditions and
needs, such as data-quality objectives and site accessibility. Sampling
and monitoring should occur at various locations (including the water
supply, along parts of the water distribution system, the treatment
system, and at critical water usage areas) to help provide an analysis
over time of the contamination levels at various points in the water
system. Periodic monitoring also should be done at other locations along
the water system to detect any new occurrence of the contaminant of
concern. The plan will also address how sampling may vary over time,
such as a reduction in sample frequency. All of this should be
documented in the post-remediation monitoring plan.

## Return to Normal Operations 

After the water source and/or distribution system has been treated and
rehabilitated, the water utility should continue sampling and monitoring
activities to confirm that the remediation goals have been attained.
Based on sampling and analysis results, the water utility and the
responsible agency (i.e., primacy agency and/or health department)
should determine whether the contamination problem is mitigated and the
water system can be returned to normal operations. This is the last step
of the response action (as presented in Module 2, Figure 2-8).

Even if a determination is made that the water system can be returned to
normal operations, the water utility and the primacy agency and/or
health department) should continue to provide public communications to
strengthen public confidence in the water system and to provide
consumers with information on the contamination incident, the nature of
the contaminant, the rehabilitation and recovery actions, the continuing
sampling and monitoring plan, and the results of ongoing sampling.

# Long-Term Alternate Domestic Water Supply

Depending on the nature and severity of the contamination incident and
the technical feasibility for rehabilitation, a decision will need to be
made regarding whether a long-term alternate or replacement water supply
will be necessary for public consumption, sanitation, and/or
firefighting purposes. This decision must be made by the lead agency
responsible for consequence management, with input from the water
utility, drinking water primacy agency, public health officials, and the
appropriate state and federal officials. Under this circumstance,
increased public communication regarding the status of the water supply,
storage, and water distribution system should be implemented (see
Section 7 of this module).

Table 6-3 outlines the basic framework for determining the possible need
for a long-term alternate water supply based on the anticipated level of
restriction that will be placed on drinking water use.

[]{#__RefHeading___Toc69893190 .anchor}Table 6-3. Relationship Between
Long-term Restriction and Need for Long-term Alternate Water Supply

  ----------------- -------------------------------------------------------
  **Restriction**   **Alternate Water Supply Needed**

  Boil Water or     None
  Other             
  Point-of-Use      
  Purification      

  Do Not Drink      Alternate water supply necessary for consumption, food
                    preparation, etc. Existing water can continue to be
                    used for sanitation/firefighting

  Do Not Use        Alternate water supply necessary for consumption and
                    sanitation. Alternate supply may also be needed for
                    firefighting.
  ----------------- -------------------------------------------------------

If the water is deemed safe for all uses or can be treated and rendered
safe (e.g., by boiling or other point-of-use purification method) by the
consumer, then a long-term alternate water supply may not be necessary.
If point-of-use purification is applied, the lead agency should verify
that the method is capable of removing the contaminant to levels that
are protective of public heath, that the method can be implemented
everywhere in the contaminated area of the system, and that failure or
misapplication of the point-of-use method will not result in acute
health risks.

If the public is asked not to drink or use the water, then the response
should consider provisions for an alternate drinking water supply (see
Figure 5.5 in Module 5). If the restriction is only on consumption, then
the suspect water can still be used for all other activities that do not
involve ingestion of the water; it will only be necessary to provide an
alternate drinking water supply for consumption and related activities
such as food preparation. A "do not use" order is much more restrictive
and should consider how other needs of the community, such as sanitation
and firefighting, will be met.

Module 5 addressed considerations for short-term alternate water supply
needs. In Module 5, providing alternate water supplies once a threat was
deemed 'credible' is a precautionary action to limit/prevent exposure
while efforts are undertaken to confirm the incident. This section deals
with efforts to provide long-term alternate water supply during
remediation and recovery activities. Two scenarios are discussed: (1) a
long-term alternate water source and/or method of water distribution is
needed until rehabilitation is complete or (2) a replacement water
source and/or distribution system is needed. Generally there will not be
a clear, well-defined transition from short-term alternative water
supply needs to implementation of measures to address long-term needs;
rather, it is more likely to be an evolving effort as the threat is
confirmed, the magnitude of the need is realized, and a realistic
timeframe for remediation and recovery is established. The key
distinctions between short-term and long-term water supplies are:

-   Short-term supply options are those that can be implemented
    immediately or quickly (within hours or days). Many such options,
    however, may not be sustainable for a long period or able to meet
    full normal demand.

-   Long-term supply options are those that can meet demand for the
    duration of the remediation and recovery effort. These options may
    take longer to mobilize.

In both of the scenarios described above (long-term alternate supply or
permanent replacement supply), the long-term implications of supplying
water to affected communities will be challenging. If the water source
and/or distribution system (including the water storage system) can be
recovered and rehabilitated or replaced, then the lead agency (with
support from the water utility) should plan on providing a long-term
alternate water supply for consumption and potentially for sanitation
and firefighting purposes. In addressing the issue of providing a
long-term alternate water supply, the responsible party will need to
consider the potential duration of disruption of normal water supplies
and the associated demand needs, identifying water supply alternatives,
and implementing the long-term supply alternatives.

Figure 6-4 shows an overall approach for identifying and implementing a
long-term alternate water supply. The approach is described in detail in
the following section. In addition, US EPA's *Guidance Document for
Providing Alternate Water Supplies* (US EPA, 1988b,
<http://www.epa.gov/cgi-bin/claritgw?op-Display&document=clserv:OSWER:1418;&rank=4&template=epa>)
provides guidance on how to develop or obtain alternate water supplies
where releases of hazardous substances or pollutants have resulted in
closure of drinking water wells or contamination of a principal drinking
water supply. The document was prepared to assist Superfund contractors
and on-scene Federal, state, and local officials with the planning and
implementation of alternate water supplies at uncontrolled hazardous
waste sites. It includes provision of new supplies and treatment or
redistribution of existing supplies and may be applicable to the
identification, selection, and development of a permanent long-term
alternate water supply due to a contamination incident.

## Determining Supply Needed to Meet System Demands

Demand needs for short-term and long-term alternate water supplies are
likely to be different. Demand needs for temporary alternative water
supply will likely be reduced by restrictions placed on water use. For a
replacement alternate water supply, the water utility should plan based
on the quantity of water necessary to meet normal customer demand. This
information will be useful in identifying options for alternate drinking
water supplies and selecting the most appropriate option. To understand
water supply demand, the water utility should estimate average daily,
maximum daily, and peak hourly demand; however, water supplies are
normally sized based on maximum instantaneous demand.

![](media/image1.wmf)

[]{#__RefHeading___Toc70487198 .anchor}Figure 6-4. Conceptual Framework
for Implementing a Long-term Alternate Water Supply

### Estimating Normal Demand

In considering a replacement water supply, water demand may be estimated
from the following:

-   Metered consumption data for the community (both for residential and
    for commercial/industrial) based on historical usage. Water
    utilities should have these data, provided that computer systems and
    historical records are available.

-   Extrapolations from data on per capita water use rates observed by
    municipal supply facilities in the general area.

-   Estimated demand from general per capita rates. For residential use,
    an average daily consumption of 80-100 gallons per day per capita
    can be used and commercial/industrial usage may be estimated to
    average 2,500 gallons per connection per day. These values may vary
    depending on location. (Metered consumption data are preferred
    because they are more accurate than the listed guidelines.)

### Restricting Demand Through Conservation

Given the extraordinary circumstances associated with a drinking water
contamination incident and the potential length of the remediation
effort, it may not be possible to meet normal demands. In fact, severe
and mandatory water conservation actions will likely be necessary to
curtail demand and meet the needs of critical customers. For instance,
firefighting and other emergency needs (e.g., hospitals, nursing home,
and other care facilities) will need priority consideration. Water
utilities should already have identified their high priority water
customers and locations.

Water conservation actions could include:

-   Use prohibitions, including watering lawns, washing cars, etc.;

-   Restricting water access; for example, limiting water usage to
    several hours a day; and

-   Restricting commercial water usage, including prohibiting certain
    high water usage processes or requiring companies to secure water
    supplies independent of the domestic water supply until remediation
    or replacement.

The World Health Organization has established a minimum water need
estimate of just under 4 gallons/day per person for drinking water and
cooking. Other organizations have suggested a minimum of 13 gallons/day
per person to allow for both dietary and other water needs, such as
water needed for washing laundry (Roberts, 1998,
<http://www.icrc.org/web/eng/siteeng0.nsf/iwpList464/3DCA2C690E52732FC1256B66005C8941>).
These are well below the United States normal per capita water usage
identified above, and may be useful in estimating minimum system demand.

## Identifying Long-Term Alternate Water Supplies

As explained in Module 5, Section 6, water use restrictions may be
necessary following a contamination incident. It may be necessary to
keep these water use restrictions in place until the water source and/or
distribution system is rehabilitated or replaced and returned to normal
operation. An alternate water supply may be needed for the duration of
remediation and rehabilitation activities.

When evaluating options for an alternate water supply, a broad array of
options should be considered by the water utility. The water utility
should first identify the resources that are available to provide a
long-term alternate water supply and the feasibility of utilizing each
resource. The option(s) selected should be those that best fit the water
system characteristics and are feasible from cost and logistical
standpoints. The water utility may use a combination of alternate water
supplies for economic reasons and to ensure that uncontaminated water is
provided to all consumers. Because this will be a long-term activity,
the cost of the alternate water supply warrants consideration.

### Options for Alternate Water Supplies

As part of its ERP, the utility should identify available alternate
water supplies. This source list should be maintained to include
accurate information on points of contact for alternate supplies (i.e.,
haulers, adjacent communities, neighboring utilities). As explained in
Module 5, as part of their emergency response planning, water utilities
should identify agencies or private companies that could provide water
supplies (bottled or bulk) in the event of a water contamination event
and establish *mutual aid agreements* with surrounding communities,
industries, contractors and related utilities. Local businesses such as
dairies, well drillers, distributors, or railroads may have tank trucks
that can be made suitable for carrying water. Other companies may have
equipment such as chlorinators or generators. Irrigation supply
companies may have pipe that can be used to extend water supply lines.
Other water utilities in the area may have spare parts (valves, pumps,
pipe) that may be available for use in an emergency. These groups may
also be able to supply personnel to assist during emergencies.

There is a possibility that a sufficient and readily available alternate
water supply already exists. A readily accessible alternate water supply
of sufficient quality and yield may reduce the importance of rapid
remediation for the water supply system and provide more flexibility
where a technically difficult remediation and rehabilitation is to be
conducted.

Module 5, Section 6 identifies possible alternate water supplies and
backup water supplies. Section 6.3 of this module also discusses
long-term water supply options.

### Who Provides the Alternate Water Supply?

The water utility and local authorities may not have the resources to
provide a long-term alternate water supply. In such cases, assistance
will be needed from state and federal authorities such as the US EPA,
USACE, and FEMA. The overall responsibility for accomplishing recovery
of public facilities, including water utilities, rests with State and
local governments. At a minimum, State authorities with support from
federal authorities will coordinate the provision of a long-term
alternative water supply.

When a significant incident calls for federal assistance or when the
President declares a major disaster or an emergency, including terrorist
acts, the FRP provides the mechanism for federal departments and
agencies to coordinate delivery of Federal assistance and resources to
assist State and local governments (FEMA, 2003,
<http://www.fema.gov/pdf/rrr/frp/frp2003.pdf>). Under the FRP ESF #3,
Public Works and Engineering Annex, the USACE, which is part of the
Department of Defense, serves as the primary agency. Responsibilities
under ESF #3 include emergency restoration of critical public
facilities, including the temporary restoration of water supplies, and
emergency contracting to support public health and safety, such as
providing for potable water.

### Selection of Alternate Water Supplies

The water utility and/or local authority should first identify those
resources that are available to provide a long-term alternate water
source and/or distribution system. They should then evaluate the
feasibility of providing a permanent alternate water supply versus
continuing to provide a temporary alternate water supply. The
feasibility of providing an alternate water source and/or distribution
system should be assessed using the following criteria:

1.  The time and cost necessary to develop an alternate water source
    and/or distribution system;

2.  The quality of the alternate water source and/or distribution
    system;

3.  The reliability of the alternate water source and/or distribution
    system;

4.  The sustainable quantity, or safe yield, of the water source and/or
    distribution system, considering the water use demands of those
    current users affected by the contamination incident, any current or
    potential competing demands, as well as any water rights issues; and

5.  Whether the alternate water source and/or distribution system is
    itself irreplaceable (i.e., is there a backup to the alternate
    supply).

To evaluate water supply alternatives, the water utility needs to have a
comprehensive understanding of the current water supply, the water
distribution system, water system demand, uncontaminated water supply
systems in the vicinity, and the location and capabilities of other
regional supply systems, including available excess capacity and ease of
connection to the existing water distribution system. Site maps,
topography maps, and US Geological Survey maps may assist the water
utility with a visual representation of its water supply system and the
available alternate water supplies.

As discussed in Module 5, Section 6, a "do not use" notice may have
implications for water used for firefighting. If this is the case, then
an alternate supply of water for firefighting may be necessary. It may
take some time to mobilize alternate water supplies for firefighting
purposes for the long term. Therefore, in the short term, contaminated
water may need to be used for firefighting purposes as an undesirable
alternative.

As part of their emergency response preparations, water utilities should
make agreements with surrounding communities to utilize their water
supplies for firefighting purposes. Pumper trucks should be filled at
the community water supply and kept at the fire department for
firefighting purposes. Federal agencies such as the USACE, FEMA, and the
Forest Service may be able to provide firefighting equipment and water
for firefighting purposes.

### Public Awareness

In conjunction with providing a long-term alternate water supply, the
water utility should continue the public awareness program described in
Module 5, Section 6. Information about the long-term alternate water
supply should be communicated to water consumers and the public using
the previously discussed communication delivery vehicles (e.g., public
notices, mailings, bulletin boards, hand-to-hand delivery, telephone,
newspapers, radio, television, internet, and fax). Public presentations,
meetings and workshops are effective for explaining the long-term
alternate water supply and instructions for its use. Information about
the long-term alternate water supply and supporting information should
be maintained at the information repository.

The utility may also advise consumers to maintain an emergency supply of
water such as bottled water, and provide water consumers with
information regarding the alternate water supply and how long the
alternate water supply will be used.

## Implementation of Long-Term Water Supply

The water utility and local, state, and federal officials should develop
a plan to meet consumer demand within the original water supply system.
The plan should include an analysis that examines the costs of the
various options, the time necessary to develop alternates, an
engineering analysis of the options, an environmental impact assessment
of the options, and the ability of the alternates to meet the existing
water demands.

Module 5, Section 6 identifies possible alternate water supplies
applicable for the short term. The following are examples of long-term
water supply options:

-   Connection of the water distribution system to an existing municipal
    or private water supply (assumes existing water treatment plant and
    distribution system is intact and useable).

-   Connection of the water distribution system with a new
    uncontaminated ground water or surface water source (assumes
    existing water treatment plant and distribution system is intact and
    useable).

-   The development of a new temporary water distribution system
    (assumes existing water treatment plant and source water is
    uncontaminated and useable).

-   The development of a new temporary water treatment plant (e.g.,
    using portable equipment) (assumes source water and existing
    distribution system are uncontaminated and useable).

### Connection to Existing Municipal or Private Supplies

If there is a public water source and/or distribution system in close
proximity, with an adequate water supply, then connection to the
existing water source and/or distribution system may be a viable
long-term alternate water supply option. Some water systems may have
existing interconnections to other systems, and the capacity of these
interconnections to supply sufficient quantities should be evaluated.
Where existing interconnections are insufficient (e.g., if pipe
diameters are too small), new connections may be necessary. Whenever
possible, existing supplies should be used in implementing alternate
water supplies.

### Connection to New Water Source

The use of alternate surface water or ground water sources, while
requiring significant infrastructure development, may be a feasible
option, particularly if the alternate water source is in close proximity
to the existing water source.

If a ground water source (i.e., an aquifer) becomes contaminated, new
ground water sources that may be available include (1) shallow wells
that can be drilled upgradient of the contamination source, and (2) deep
wells that can be drilled into an aquifer underlying a contaminated
aquifer. If an uncontaminated aquifer is located below the contaminated
aquifer and is not hydraulically connected to it, then new wells can be
drilled in the deeper aquifer. It is difficult, however, to demonstrate
conclusively the absence of hydraulic connections. Therefore, this
option should only be used in cases where no other water supplies are
available. Any new wells drilled away from the contaminated source
should incorporate controls to prevent contaminant migration.

If a surface water source (e.g., a lake) becomes contaminated, new
surface water sources that may be available include streams, rivers,
ponds, lakes, and reservoirs located upstream from the contaminated
water supply. If these surface sources have adequate watershed yield and
quality, then they may be located downstream of the source, provided
that the surface supply is not hydraulically connected to the
contaminated water source or, if downstream, is sufficiently distant
from the contaminated source so that it is not significantly influenced
by that source. The latter approach would likely requires some level of
monitoring to demonstrate that the new source is not contaminated

### Temporary Treatment and Distribution Systems

If an incident renders a water treatment plant unusable, it may be
possible to replace the treatment capacity during remediation using
portable equipment. Section 4.1.2 of this module includes information on
whether specific treatment technologies are available in portable
designs. Sources of portable treatment equipment may include the
National Guard, reserves, or other arms of the military. Similarly, if a
section of distribution system is unusable, it may be possible to supply
water to an area using irrigation pipe or flexible, above-ground plastic
piping. Water utilities commonly use such methods during relining of
water mains.

# Public Communication

When remediation, recovery, and rehabilitation activities are near
completion, the water utility (and other cooperating agencies) will need
to prepare the water system and its customers to return to normal
operations. This is a critical time for providing effective and
continual communications with water customers. Module 5, Section 5
introduced the concept of a "comprehensive communications strategy,"
which addresses the "who, what, why, where, when, and how" of providing
information to the public and details the message, audience, potential
vehicles, resources needed, and feedback mechanisms. It is assumed that
the water utility already has developed a communications plan that will
be used during an emergency. The goal of this comprehensive
communications strategy is to enhance the effectiveness of the water
utility's communication plan during a contamination incident. It is
important to note that the communication strategy will be managed
through the Incident Commander, which may or may not be the utility at
this stage of a response. However, even if the utility is not in charge
of the incident at this point, the Incident Commander may delegate
responsibility for the communication strategy to the utility.

The communications discussion will address comprehensive communications
during water system recovery and return to normal operations. This will
involve providing revised water use notifications to the public,
communicating with the public on water supply alternates, advising the
public of remediation and recovery options, notification of estimated
time to return to normal operations, and providing information on
continued monitoring and analysis of the water system after remediation.

During system recovery, various methods of communication will be
appropriate for providing this information, as described in Module 5,
Section 5. The communication needs will change throughout the recovery
process, from providing information regarding alternate water supply to
instructions during the return to normal operations. Effective
communication by the water utility and appropriate officials will help
alleviate the fears of consumers, allow active participation by the
public during the various stages of the contamination incident, and
allow for documentation of the information communicated to the water
consumers during all stages of the contamination incident. Coordinating
communication among the parties involved is critical to avoid sending
conflicting messages to consumers.

## Agencies Involved in Communication

If the contamination event calls for federal assistance and is declared
a major disaster or emergency, then the DHS may implement community
relations and public affairs activities. Additionally, the water utility
and/or the drinking water primacy agency will be involved in
communication throughout incident response. Activities from each of
these organizations are presented below.

### Department of Homeland Security

When a significant incident calls for federal assistance or when the
President of the United States declares a major disaster or an
emergency, the FRP (FEMA, 2003,
<http://www.fema.gov/pdf/rrr/frp/frp2003.pdf>) provides the mechanism
for federal departments and agencies to coordinate delivery of Federal
assistance and resources to augment efforts of State and local
governments overwhelmed by a major disaster or emergency, including
terrorist acts. Under the FRP Public Affairs Support Annex, the FBI and
DHS are responsible for implementing Federal public affairs activities
after a major disaster or emergency. DHS will develop strategic plans
and policies, provide liaison with the directors of public affairs for
other Federal agencies and the White House press office, and determine
the need for a *Joint Information Center* (JIC).

In a major disaster or emergency, a JIC will be established as a central
point for coordination of emergency public information, public affairs
activities, and media access to information about the latest
developments regarding the incident. The JIC is a physical location
where Public Affairs Officers from involved agencies come together to
ensure the coordination and release of accurate and consistent
information that is disseminated quickly to the media and the public. A
JIC may be established at DHS Headquarters and/or near the scene of the
incident (water utility). Release of information between the two will be
coordinated to the maximum extent possible. See the FRP for the primary
functions of the JIC.

Under the FRP Community Relations Annex, the DHS, in conjunction with
the disaster-affected State, ensures an efficient and reliable flow of
disaster-related information between victims and organizations that
provide assistance. DHS will work with Federal, State, and local
governments to help citizens and communities recover from the effects of
a major disaster. DHS will send field officers into affected communities
after a major disaster to gather and disseminate information about the
disaster response and recovery process. DHS will serve as a direct link
to these communities and works in close coordination with other program
elements to develop and deliver messages related to the availability of
Federal disaster assistance.

### Water Utility and/or Drinking Water Primacy Agency

If the contamination calls for federal assistance under the FRP, DHS
likely will seek assistance from the water utility and/or drinking water
primacy agency to ensure that the appropriate information is being
communicated effectively to the public during rehabilitation activities.
Shortly after the contamination incident was confirmed, the public would
have been notified about the incident, would have received the
appropriate notices ("boil water," "do not drink," or "do not use"), and
may have received additional information about the contaminant,
precautions to take, and planned response and recovery actions.
Communication during the remediation and return-to-normal operations may
not need to be as expeditious as during the initial stages of incident
response; however, the communication needs to be just as effective and
will now involve more detailed information and increased interaction
with the drinking water consumers.

## Forms of Communication

Module 5, Section 5 describes a comprehensive communications strategy,
which is also relevant to communications during drinking water system
remediation. Communications during remediation and return to normal
operations involve the same audience and many of the same basic
communication delivery vehicles (e.g., public notices, mailings,
bulletin boards, hand-to-hand delivery, telephone, newspapers, radio,
television, internet, fax, and videos). Some other communication
delivery vehicles that will be used at the rehabilitation stage include:

-   Public meetings;

-   Public presentations;

-   Public workshops;

-   Public information repository; and

-   Revised Public Notifications.

Suggestions for effective public events (meetings, presentations, and
workshops) include:

-   Providing two to three weeks prior notice of the event, with a
    follow-up notice a few days before the event, if possible.

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-   Whenever possible, use handouts, slides, posters, maps, and
    photographs.

-   Consider using videos to introduce messages or technical concepts
    that will be discussed in greater detail.

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-   Prepare an agenda and compile presentation materials and handouts
    for the participants well in advance of the event. Provide these
    items with the event notice.

-   Have attendees sign in for the event and provide contact
    information.

-   Start the event on time.

-   Take breaks during longer events such as meetings and workshops.

-   Keep presentations brief and focus on one or two key items.

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-   For participatory events such as workshops, ensure that the event
    location can be set up in a manner that is conducive to the
    participatory nature of the event.

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-   Remember: two-way communication. Resist the temptation to think of
    the public meeting merely as an expedient way to get information out
    to as many people as possible. Expect questions, statements,
    posturing, grandstanding, antagonism, support, anger, and
    frustration.

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-   Be honest. If you do not have the answer, then promise to follow up.

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-   Ask for feedback and evaluations of the event so that improvements
    may be made for future events.

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-   Document and record the event. Send a summary of the event to
    attendees and to the media for publication.

    In all of its communication strategies, the utility should be
    careful not to compromise the security of its facilities and release
    information regarding vulnerabilities into the public domain. The
    sections below provide additional information on each form of
    communication.

### Public Meetings

The public meeting is a public forum that is fairly structured and
formal in nature, and open to the general public (i.e., drinking water
customers). The public meeting provides a forum for water consumers and
others to interact with the officials from the water utility, lead
agency, and other participants in the remedial action and to voice their
concerns and questions. The purpose of the public meeting is to present
information to the audience and to receive information back from them.
Presenters should include the water utility and/or primacy agency as
well as other officials. Public meetings should be effective
communication vehicles to disseminate information on the alternate water
supply, identify and discuss the remediation and recovery option that is
being implemented, and discuss the time estimated for the water system
to resume normal operations.

The public meeting should be held in a location that is convenient and
easily accessible to the majority of water consumers, including any
disabled residents. The location should be capable of accommodating the
anticipated crowd, handle any lighting, ventilation and electrical
needs, and have adequate, convenient, well-lighted parking.

The water utility and/or appropriate agency should notify the media,
either via a press release or media advisory, as an additional means of
notifying the public about the meeting. Even if the meeting was
advertised through a public notice, it should not be assumed that the
water consumers paid attention to the public notice. Opportunity for
media access should be considered at the meeting location several hours
before the start of the meeting. This will provide the media with
visuals and an opportunity to ask questions. The media may air the press
conference on the early evening news, which will likely increase
attendance at an evening meeting. Providing media access before the
meeting can help streamline interactions with the media, and may give
the water utility and appropriate agencies insight into issues that may
not have been considered in preparing for the meeting.

### Public Presentations

A public presentation is an organized oral communication to an audience.
Presentations can be enhanced with visual aids and question-answer
sessions. This vehicle should be used to make a formal announcement,
such as a revised public water use notification, or to keep the water
consumers and the community up-to-date regarding the progress of
remediation efforts. Presentations also can be used to prepare the water
consumers and the community prior to significant events or decisions,
such as the implementation of remediation and recovery actions or
selection of an alternate water supply.

As with meetings, presentations need to be promoted ahead of time.
Presentations should be advertised through the media and through
mailings. Presentations should be scheduled at convenient times and
locations. A press conference should be held prior to the presentation
if possible. Presentations are most effective when they are planned
around major events.

### Public Workshops

Workshops are formal, participatory seminars used to educate the
participants and develop or improve the involvement of water consumers,
local officials, and other interested parties. Technical experts may be
invited to offer an inside perspective and to increase the effectiveness
of the workshop. Workshops may be a very powerful tool for formally
educating small groups of citizens and water consumers on: 1) provisions
for alternate water supply; 2) public notices regarding water use
restrictions; 3) decontamination and treatment options; and 4)
remediation and recovery activities.

The educational, public involvement, and empowerment values of workshops
make them a key component of the community outreach and involvement
process during rehabilitation and return to normal operations following
a contamination incident. Workshops provide more than just "another
meeting;" they offer knowledgeable, active citizens the chance to gain
in-depth understanding of the issues surrounding the contamination
incident, response to the incident, and remediation efforts. They also
provide citizens and water consumers the chance to communicate directly
with experts about advanced concepts and issues and to develop community
organization and participation skills that will improve community
involvement. Workshops provide small groups of citizens with an
interactive learning environment. A good workshop will include citizen
participation and provide an excellent forum for concrete planning of
next steps and action items.

As with meetings and presentations, workshops need to be promoted ahead
of time and should be advertised through the media and through mailings.
Workshops should be scheduled at convenient times and locations.

### Public Information Repository

An information repository is a record storage facility at a location
easily accessible by the public (such as a public library) that contains
all correspondence, reports, and documents pertaining to the
contamination incident and response, recovery, and rehabilitation
activities. Some common locations include public libraries, city halls,
and public health offices when public access is convenient and
photocopying equipment is available. Alternative locations include fire
stations or religious buildings. The repository should be accessible
during normal business hours. Large and medium water systems may need
multiple repositories.

The information repository should be established at the beginning of
remediation planning activities and well publicized to water consumers
using the communication delivery tools previously discussed. Summaries
of public meetings, presentations, and workshops should be maintained at
the repository. At an information repository, water consumers and
citizens can research the contamination incident, research important
health information and public notices, research information on alternate
water supplies and remediation and rehabilitation activities, and copy
any information found at the repository.

The repository could be developed along with a toll-free information
telephone line for water consumers to obtain the latest health
information, public water use notices, instructions on obtaining
alternate water, information on remediation and rehabilitation
activities, and information on the water system's return to normal
operations. The web site of the utility or municipality can also be used
to provide public access to information.

### Revised Public Notifications

During the rehabilitation stage, the water utility and/or appropriate
agency should continue providing public drinking water notifications to
the water consumers. These communications are necessary as a reminder to
the water consumers and also may be necessary if the public notification
needs to be revised. For example, if a "do not use" notice was issued
initially because the contaminant was originally unknown, it might be
revised once the contaminant has been identified based on the actual
risks posed by the specific contaminant. Additional information
regarding public notifications is provided in Module 5, Section 5.

Water consumers may be skeptical about a revised public drinking water
notification and may be hesitant to heed the revised instructions;
therefore, additional information needs to be provided with the revised
public notification explaining why the notification is being revised. An
information hotline telephone number should also be provided for water
consumers to call to get additional information and to have questions
answered.

Revised public notices should be communicated to water consumers and the
public using the previously discussed communication delivery vehicles
(e.g*.*, public notices, mailings, bulletin boards, hand-to-hand
delivery, telephone, newspapers, radio, television, internet, and fax).
It will be effective for the water utility and/or appropriate agency to
hold public meetings and public workshops to explain to the water
consumers the reasons for a revised public drinking water notification.
The revised public drinking water notification and supporting
information should be maintained at the information repository.

## Types of Information to be Communicated

During the remediation, rehabilitation, and recovery activities, the
water utility and responsible agencies will need to continue
communicating to water consumers. Information to be communicated may
include information on the alternate water supply, the remediation and
recovery options that are being evaluated and ultimately selected, the
time estimated to return to normal operations, information on continued
monitoring and analysis of the water system after water system
remediation, and additional instruction to consumers as necessary.

### Alternate Water Supplies

During remediation and recovery activities, a long-term alternate water
supply will be implemented (see Section 6 of this module). The water
utility and/or appropriate agency will need to provide the water
consumers with information on the long-term alternate water supply,
along with necessary instructions such as where to obtain the water,
whether the water needs to be boiled, whether users need to supply their
own containers, whether the alternate water will be supplied through the
current distribution system, etc.

Water consumers may be confused by the information on use of the
long-term alternate water supply and may also be skeptical about the
quality of the alternate water supply. Therefore, the water utility
and/or appropriate agency should provide additional information to the
water consumers about the alternate water supply (i.e., fact sheet). An
information hotline telephone number also should be provided to water
consumers as a source of additional information.

Information about the long-term alternate water supply should be
communicated to water consumers and the public using the previously
discussed communication delivery vehicles (e.g., public notices,
mailings, bulletin boards, hand delivery, telephone, newspapers, radio,
television, internet, and fax). Also, it will be effective for the water
utility and/or appropriate agency to hold public presentations, public
meetings and public workshops to help better explain the long-term
alternate water supply and instructions for its use. Information about
the long-term alternate water supply should be maintained at the
information repository.

### Remediation and Recovery Activities

The water utility and/or agency responsible for remediation activities
will need to communicate to the public the various remediation and
recovery activities that are occurring within the drinking water system.
As part of these communications, water consumers need to be informed of
potential remediation activities that will affect their homes or
businesses. Communications should address consumer and business
equipment such as water treatment and filter devices (either installed
at the faucet or on the main water line inside the building or house),
coffee makers, icemakers, water heaters, garden hoses, sprinklers,
toilets, spas, and swimming pools. Consumers should be advised of
whether the equipment is usable or not, be provided with instructions on
how the equipment can be cleaned or decontaminated (either by the
consumer or by a professional), and/or provided with accurate
information regarding the logistics for collection and disposal of
non-usable equipment. Specific decontamination methods for household
equipment are being researched by US EPA another organizations.

Information about the remediation and recovery activities may be too
technical for a simple fact sheet or notice communicated to water
consumers and the public using the previously discussed communication
delivery vehicles (e.g., public notices, mailings, bulletin boards, hand
delivery, telephone, newspapers, radio, television, internet, and fax).
It will be necessary and more effective for the water utility and/or
appropriate agency to hold public meetings and workshops to better
engage the public in the process and provide an opportunity for more
detailed explanation of remedial activities. Information from workshops
and meetings should be maintained at the information repository. Also,
an information hotline should be set up to provide water consumers with
additional information.

### Water System Return to Normal Operations

After remediation and recovery activities are completed, a determination
will need to be made by the water utility and appropriate officials on
whether the water system can resume normal operations. The water utility
and or appropriate agency should have public meetings and workshops to
share information with the water consumers regarding the effectiveness
of the remediation and recovery activities, the resumption of the water
system's normal operations, and the continued monitoring of the water
system following the resumption of normal operations. These public
meetings and workshops should be advertised through the previously
discussed communication delivery vehicles, and the summary of the public
meetings and workshops should be maintained at the information
repository.

### Continued Sampling and Analysis

Consumers may be skeptical about the quality of the water supply
following the return to normal operations. To allay these fears, the
water utility will need to perform routine monitoring of the water
system and share the monitoring results with the consumers in an open
and transparent manner. These monitoring results should be presented in
a simple, easy-to-read, non-technical format and communicated to the
public using the previously discussed communication delivery vehicles
(e.g., public notices, mailings, bulletin boards, hand-to-hand delivery,
telephone, newspapers, radio, television, internet, and fax). It will be
effective for the water utility and/or appropriate agency to hold public
meetings to help better explain the results of the continuous monitoring
activities.

A dedicated information hotline telephone number and/or web page should
provide consumers with detailed information on the monitoring activities
and results. The monitoring information should be maintained at the
information repository.

# References and Resources

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Treatment: A Handbook of Community Water Supplies. 5^th^ Edition.
McGraw-Hill.

AWWA. 2004a. AWWA Products - AWWA Standards.
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AWWA. 2004b. AWWA Bookstore. <http://www.awwa.org/bookstore/>

AWWA. 2004c. AWWA Buyers Guide. <http://www.awwa.org/buyersguide/>

American Water Works Association Research Foundation (AWWARF). 2004.
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American Water Works Association and American Society of Civil Engineers
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Association of Metropolitan Sewerage Agencies (AMSA). Undated. Clean
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Casey, T.J. Unit Treatment Processes in Water and Wastewater
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Centers for Disease Control and Prevention (CDC). 2003. Chemical Agents:
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CDC. 2004. Agency for Toxic Substances and Disease Registry (ATSDR) Home
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Federal Emergency Management Agency (FEMA). 2001. United States
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FEMA. 2003. Federal Response Plan. Interim. 9230.1-PL. Supersedes FEMA
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Hammer, Mark J. Water and Wastewater Technology, 3^rd^ edition.
Prentice-Hall. 1996.

Kirk-Othmer Encyclopedia of Chemical Technology. 1997. Reverse Osmosis.
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Terrorist Actions: A Review of the Problems and Feasible Solutions.*
Prepared for the National Institute of Environmental Health Sciences

(NIEHS) Worker Education and Training Program (WETP) under contract
#273-FH-013264.

<http://www.wetp.org/front/NIEHS_rev_010303.pdf>

National Drinking Water Clearinghouse (NDWC). 2000. Fact Sheet.
Ultraviolet Disinfection: Tech Brief. September 2000.
<http://www.nesc.wvu.edu/ndwc/pdf/OT/TB/OT_TB_f00.pdf>

Occupational Safety and Health Administration (OSHA). 1985. Occupational
Safety and Health

Guidance Manual for Hazardous Waste Site Activities. Prepared by the

National Institute for Occupational Safety and Health, the Occupational
Safety and

Health Administration, the US Coast Guard, and the US Environmental
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# Appendices

## Suggested Format for System Characterization/Feasibility Study Work Plan 

I. Executive Summary

II\. Introduction

III\. System Description and Environmental Setting

IV\. Initial Evaluation and Results of Site Characterization

A. Contaminants present, volume of water and media affected

> B. Potential pathways of contaminant migration/preliminary assessment
> of public health and environmental impacts
>
> C. Preliminary identification of candidate response objectives and
> remedial response action alternatives

V. Work Plan Rationale

> A. Data quality objectives
>
> B. Work plan approach

VI\. Tasks

> A. Project Planning
>
> B. Community Relations/Public Communication
>
> C. Field Investigations
>
> D. Sample Analysis/Validation
>
> E. Data Evaluation
>
> F. Risk Assessment
>
> G. Evaluation of Remedial Alternatives
>
> H. Treatability Studies
>
> I. Reports

VII\. Costs and Key Assumptions

VIII\. Schedule

IX\. Project Management

> A. Staffing
>
> B. Coordination

X. References

XI\. Appendices

## Elements for a Quality Assurance Project Plan

I. Project Management

A. Title and Approval Sheet

B. Table of Contents

C. Distribution List

D. Project/Task Organization

E. Problem Definition and Background

F. Project/Task Description

G. Quality Objectives and Criteria

H. Special Training/Certifications

I. Documentation and Records

II\. Data Generation and Acquisition

A. Sampling Process Design (Experimental Design)

B. Sampling Methods

C. Sample Handling and Custody

D. Analytical Methods

E. Quality Control

F. Instrument/Equipment Testing,

G. Inspection, and Maintenance

H. Instrument/Equipment Calibration and Frequency

I. Inspection/Acceptance of Supplies and Consumables

J. Non-direct Measurements

K. Data Management

III\. Assessment and Oversight

A. Assessments and Response Actions

B. Reports to Management

IV\. Data Validation and Usability

A. Data Review, Verification, and Validation

B. Verification and Validation Methods

C. Reconciliation with User Requirements

## Elements of a Health and Safety Plan

I. The name of a site health and safety officer and the names of key
personnel and alternates responsible for site safety and health

II\. A health and safety risk analysis for existing site conditions, and
for each site task and operation

III\. Employee training assignments

IV\. A description of personal protective equipment to be used by
employees for each of the site tasks and operations being conducted

V. Medical surveillance requirements

VI\. A description of the frequency and types of air monitoring,
personnel monitoring, and environmental sampling techniques and
instrumentation to be used

VII\. Site control measures

VIII\. Decontamination procedures

IX\. Standard operating procedures for the site

X. A contingency plan that meets the requirements of 29 CFR
1910.120(l)(1) and (I)(2)

XI\. Entry procedures for confined spaces

## Suggested Format for System Characterization/Feasibility Study Report

I. Executive Summary

II\. Introduction

A. Purpose of Report

B. History of Contamination Incident

C. Rapid Risk Assessment

D. Summary of Site Characterization Results

E. System Description

III\. System Characterization

A. Contaminant Source Investigations

B. Source Water Investigation

C. Treatment Plant Investigation

D. Distribution System Investigation

E. System Components Investigation

F. Environmental Media Investigation

G. Public Health Investigation

H. Ecological Investigations

IV\. Nature and Extent of Contamination

A. Sources (reservoir, ground water, river)

B. Storage, treatment, and distribution system

C. Affected Environmental Media (soils, sediment, ecological receptors)

D. Affected Consumers

V. Contaminant Fate and Transport

A. Potential Routes of Migration (i.e., air, ground water, etc.)

B. Contaminant Persistence

C. Persistence in the System

D. Contaminant Migration within the System (e.g., sorption onto pipes,
solubility in water, modeling methods and results)

VI\. Risk Assessment

VII\. Preliminary Remediation Goals

VIII\. Development and Screening of Alternative for Remediation

IX\. Summary and Conclusions

## Hypothetical Example of a Contamination Threat to a Drinking Water System: Threat Warning Through Remediation and Recovery

The following example illustrates many concepts discussed throughout the
RPTB, not just those introduced in Module 6. It is intended to
illustrate the evolution of an incident, from the time the threat
warning is received through remediation and recovery. Furthermore, it
demonstrates a streamlined application of the planning framework
presented in Module 6 for the case of a "simple" contamination incident.

[Description of Treatment Plant]{.underline}

A city treats raw water from a lake and supplies drinking water to
100,000 people in the city and surrounding communities. Lake water
enters by one of two intake pipes and is pumped to the city water
treatment plant. The water treatment process consists of
pre-chlorination, screening, clarification by means of coagulation with
polyhydroxyaluminum chloride, flocculation by mechanical mixing,
followed by sedimentation. The filtration process includes granulated
activated carbon (GAC) in the filters to remove taste and odor, a
condition present in the water during the late summer when algae are
abundant. Chlorine is added again following filtration, and contact time
for disinfection is achieved in a post-filter clearwell. Ammonia is
added following the clearwell to achieve a combined residual of 1.3
mg/L. Hydrofluorosilicic acid (Fluoride) is added to the drinking water
to promote dental health. Finished water is stored in one of three
1-million gallon ground level storage tanks that supply water to
distribution. The water treatment plant has a rated capacity of 20
million gallons per day and operates at about one half of its capacity.

[Water Contamination Threat Warning]{.underline}

Day 1 - 4:30 a.m.: A security guard at the water treatment plant
observes a person leaving the fenced area surrounding the distribution
system storage tanks. The security guard calls 911, but the police do
not arrive in time to apprehend the suspect. The security breach is
confirmed when the responding officer notices that a lock was cut from
the perimeter fence. The security guard immediately activates the
facility's Emergency Response Plan (ERP) and notifies the WUERM (or ER
Lead) by telephone.

[Initial Threat Evaluation and Immediate Operational
Response]{.underline}

Based on the information provided by the security guard, the WUERM
determines that the threat is possible and further emergency response
actions are necessary. The WUERM contacts key personnel on the
facility's internal notification list. The local police mobilize their
bomb squad to evaluate the storage tanks and surrounding areas for
explosives. The plant operators implement the Action Plan established
for the storage tanks that includes both physical isolation of the water
in the tanks and maintaining an exclusion zone around each tank. By 5:30
a.m., the exclusion zone is established, and all three tanks are
physically isolated from the treatment plant and rest of the
distribution system. As a further precaution, the WUERM orders the
shutdown of segments of the distribution system closest to the tanks,
shutdown of the treatment system, and closure of both water intakes.

The police determine no explosive devices were left by the intruder or
intruders, however, an investigator finds several large empty containers
at the base of Storage Tank No. 1. Law enforcement personnel indicate
that the containers must be left in place for further investigation to
include taking photographs, fingerprints, and conducting chemical
analysis of any residues present in the containers.

The WUERM is designated as the Incident Commander (IC) under the plant's
ERP and Incident Command System (ICS) and initiates further action
(including sampling and analysis) to determine if a contamination
incident has occurred. At the same time, the spokesperson designated in
the ERP activates the public/media communications plan to keep the press
and public informed.

[Site Characterization and Sampling]{.underline}

Day 1- 6:30 a.m.: Based on observations of a suspicious person, the
broken lock, and the empty containers, the WUERM determines that the
contamination threat is credible. The WUERM directs the site
characterization team leader to immediately develop and implement a
customized site characterization plan. As the potential site of
contamination, the storage tanks are designated as the primary
investigation site. It is unclear whether or not the tanks were isolated
quickly enough to prevent the spread of water into the distribution
system; however, for the initial plan it is decided that only the
primary site will be characterized. The site characterization objective
is to determine whether or not a water contamination incident has
occurred.

Site characterization activities are initiated including implementation
of the health and safety plan and sampling and analysis of water in each
of the three storage tanks. Initial analysis is performed using field
test kits. The team conducts rapid field-testing of the water for pH,
conductivity, chlorine residual, and cyanide.

The sample analysis results indicate concentrations of cyanide in
Storage Tank No. 1 exceeding 0.2 ppm. Results for other parameters in
all three tanks were within normal limits. The site characterization
team is instructed to obtain additional samples from points downstream
of the storage tanks within the distribution system for more detailed
chemical analysis and to determine if containment measures were
effective.

Day 1 - 12:00 noon: The WUERM makes a judgment that the contamination
incident is confirmed and places a call to the drinking water primacy
agency in accordance with the plant's ERP. The primacy agency and WUERM
make the joint decision to call the National Response Center. Because
the incident is believed to be an act of terrorism, it is considered an
incident of national significance and requires action by the Department
of Homeland Security (DHS). A representative from DHS is dispatched to
the scene and assumes the role of IC, replacing the WUERM. The WUERM
assumes the role of utility representative directly under, and providing
technical advice to, the IC. Representatives from DHS and FEMA
coordinate delivery of Federal resources as needed, and a representative
from the Federal Bureau of Investigation (FBI) takes the lead role in
the law enforcement activities.

[Public Health Response Actions]{.underline}

Day 1 - 12:30 p.m.: Public health response actions are initiated to
minimize the potential for exposure of the public to the contaminated
water. Even though contamination has been confirmed through sample
analysis, the extent and severity of the contamination and the
effectiveness of containment measures is not known. Therefore, a
temporary "do not use" notice is issued for the community served by the
water treatment plant until it can be determined that the operational
response to contain the contamination has been successful. The decision
to restrict all uses of the water is made because cyanide can pose an
inhalation threat due to volatilization of hydrogen cyanide (HCN).

FEMA directs the US Army Corps of Engineers to immediately provide
short-term alternate water supply in the form of bottled and bulk water
while the more detailed site characterization activities are being
conducted. Firefighting capability is maintained by filling pumper
trucks from ground water wells used by a small community in the suburbs
of the city.

Day 1 - 4:30 p.m.: Field test kit analytical results for water in the
segments of the distribution system nearest to the storage tanks
indicate that no cyanide is present above the MCL of 0.2 ppm, and the
containment actions were effective. Pending confirmatory analysis, the
"do not use" notice is lifted and a "do not drink" notice is issued in
its place. Water in the distribution system can now be used for
firefighting. Additional sampling continues throughout the evening as
remediation and recovery actions are initiated.

[Remediation and Recovery]{.underline}

Planning

Day 1 - 6:00 p.m.: The IC convenes a meeting of key response personnel
to formulate a remediation and recovery plan. In the planning meeting,
the team engages in a systematic planning process to ensure the
information collected will be sufficient to inform the public health
response, risk assessment, and decisions related to system
characterization, remedy selection, remedy implementation, and
post-remedial monitoring. The outputs of the planning process are
summarized below:

-   **Decision Makers/Support Personnel** -- An Incident Command for
    Remediation and Recovery is established with a representative from
    FEMA now serving as the IC. Key support functions are provided by
    the water utility, state emergency management agency, drinking water
    primacy agency, and the US EPA Region.

-   **Schedule and Resources** -- The team establishes schedules for
    three objectives: (1) within 72 hours, complete sampling and
    analysis of water in the distribution system, treatment system, and
    reservoir to confirm that these areas are free of contamination; (2)
    within seven days return normal service to the community; and (3)
    within 90 days complete remediation of contaminated water, the tank,
    and other equipment. The City and the State are providing emergency
    funding. If additional funds are required, the Governor will request
    Federal assistance.

-   **Goal and Objective** - The goal of remediation and recovery is to
    return the system to service as quickly as possible, providing
    drinking water that meets drinking water standards, and protecting
    the health and safety of plant personnel and response action
    workers.

-   **Conceptual Site Model (CSM)** - Based on information collected to
    this point, it appears a granular water-soluble form of cyanide
    (e.g., sodium cyanide or potassium cyanide) was intentionally
    introduced into Storage Tank No. 1 in a quantity sufficient to
    elevate the concentration of cyanide (as simple aqueous HCN) in the
    water to greater than 0.2 ppm. On-site workers and consumers could
    be exposed to volatile HCN by inhalation (e.g., working at the
    storage tank or while showering, bathing, and cooking). The degree
    of volatilization depends on a number of factors including initial
    concentration in the water and air phases, water temperature, and
    water pH. With increased pH, less HCN is available for
    volatilization. In the aqueous phase, HCN could enter the
    distribution system and expose consumers at the point of use;
    however, initial tests indicate containment measures were effective
    in preventing the spread of contamination. The contaminated water
    appears to be contained within a single 1-million gallon storage
    tank. The system characterization will confirm the full extent of
    the contamination.

-   **Type of Data Needed** -- Chemical concentration data for cyanide
    (CN^-^) based on grab samples will be required to determine the
    nature and extent of contamination of water within Storage Tank No.
    1 and in the distribution system. Field samples will be required.
    Candidate analytical methods include the field test kit methods, EPA
    Methods 335.2, 335.3, or 335.4 (US EPA, 1993). Additional
    information will be required to support selection of a remedy
    including pH, temperature, residual chlorine content, the quantity
    of contaminated water, and maps and engineering drawings of the
    tanks and affected distribution system.

-   **Constraints to Data Collection** -- There are no known barriers to
    data collection (e.g., there are not limitations to site access by
    response personnel and weather conditions are acceptable for field
    work).

-   **Quality of Data Needed** -- The planning team establishes
    preliminary quantitative performance and acceptance criteria for
    laboratory analyses including requirements to analyze laboratory
    reagent blanks to assess contamination from the laboratory
    environment, laboratory fortified blanks to calculate accuracy as
    percent recovery, calibration blanks to verify instrument
    calibration, and duplicate analyses to check precision as measured
    by relative percent difference. Failure to achieve the performance
    criteria will require re-analysis of the affected samples.

-   **Quantity of Data Needed** -- The planning team specifies that grab
    samples must be taken at a sufficient quantity to characterize the
    full depth of the affected storage tank. Grab samples also will be
    used to characterize other parts of the drinking water system. The
    initial budget calls for at least 100 samples plus the necessary
    field and laboratory control samples. The type and number of samples
    needed to demonstrate attainment of remediation goals will be
    determined later.

-   **Boundary of the Study** -- The boundary of the study include the
    entire source, treatment, storage, and distribution system --
    however; priority for system characterization is given to the
    distribution system immediately down-gradient of the storage tanks.
    A limited number of additional samples will be taken from the source
    water, within the treatment plant, and throughout the distribution
    system to determine if the boundary of the study needs to be
    expanded. The system characterization also will address Storage Tank
    No. 1.

-   **Quality Assurance and Quality Control (QA/QC)** -- A brief Quality
    Assurance Project Plan (QAPP) will be prepared to specify QA/QC
    activities required including preparation and analysis of field and
    laboratory control samples, chain-of-custody procedures, and
    technical system performance audits and evaluations. To facilitate
    rapid deployment of the system characterization team, the document
    will only contain the information necessary to address the work to
    be performed.

-   **Analytical Laboratories** -- Cyanide is a routine analysis. The
    drinking water primacy agency has a capable laboratory under
    contract and makes it available to receive and analyze the samples
    on an expedited basis.

Rapid Risk Assessment

Day 2 -- 8:00 a.m.: Under the direction of the IC, a Rapid Risk
Assessment Team from the USEPA Region is assigned to evaluate existing
data, assess short-term and long-term health risks posed to on-site
workers and the public, develop information to inform the public about
risks posed by the contamination incident, and establish an preliminary
remediation goal (PRG).

Based on concentration data from the site characterization, the risk
team determines the primary exposure route of concern for consumers is
ingestion. Inhalation and dermal absorption also are recognized as
possible exposure routes; however, dermal exposure is considered a minor
factor driving risk due to high concentrations of cyanide required to
cause toxic effects and the fact that HCN and CNCl would be lost due to
volatilization. Inhalation risks, however, are of highest concern for
response action personnel working at Storage Tank No 1, and measures are
incorporated into the Health and Safety Plan to require air monitoring
and respiratory protection for workers at Storage Tank No. 1.

The EPA team provides information on short-term and long-term health
effects of ingestion of cyanide via drinking water. Short-term exposures
to cyanide at concentrations above the MCL potentially cause rapid
breathing, tremors and other neurological effects. Long-term (lifetime)
exposure to cyanide at concentrations above the MCL causes weight loss,
thyroid effects, and nerve damage.

Under the National Primary Drinking Water Regulations, the MCL and MCLG
for cyanide is set at 0.2 ppm. The PRG is set at 0.2 ppm, a
concentration that would be protective of all exposure routes.

System Characterization

Day 2 - 11:00 a.m.: Under the direction of the IC, the remediation and
recovery team from the US EPA prepare a System Characterization Work
Plan and Sampling and Analysis Plan (SAP) using existing information
from the initial site characterization and planning meetings, outputs of
the rapid risk assessment, and information provided in the Plant's ERP.
The remediation and recovery team also is directed to update the
existing Health and Safety Plan. The team is given 24-hours to prepare
the plans and mobilize the system characterization team.

Day 2 -- 4:00 p.m.: The FBI informs the IC that the residue found in the
empty containers at Storage Tank No.1 is potassium cyanide. The IC
instructs the remediation and recovery field team to modify the SAP to
address soil characterization in the area where the containers were
found.

Day 3 -- 12 noon: The remediation and recovery team begins to implement
the system characterization using a dynamic work plan approach to allow
the project team to make decisions in the field about how subsequent
site activities will progress. The field team obtains over 100 samples
to characterize the nature and extent of contamination in the source
water, within the treatment system, in the storage tanks, the
distribution system, and at several point-of-use locations. Additional
samples are obtained of the sediment at the bottom of the tank and
biofilm on the tank wall. The highest priority is placed on sampling
water from the distribution system. The field team collects samples in
duplicate to facilitate analyses by both the Utility and the State's
contractor laboratory. Water quality parameters also are checked using
field instruments. The team requests a turn-around time of 24 hours.

Day 5 -- 6:00 a.m.: The IC and remediation and recovery team receives
and reviews all analytical results. The sample analysis results confirm
that the contamination is restricted to Storage Tank No. 1. The Utility
ensures that finished water bypasses Storage Tank No. 1 and restarts
water treatment and distribution. The "do not drink" notice is lifted.

The US EPA reports soil sample analysis results to the IC. All samples
are negative for potassium cyanide.

Feasibility Study

Days 2 through 6: Concurrently with the System Characterization, members
of the remediation and recovery team begin to implement the Feasibility
Study to specify the remedial action objectives, identify candidate
remedial options, and screen the candidate remedial options. The initial
evaluation focuses on the contaminated water and the storage tanks.

Remedial Action Objective: The initial remedial action objective is the
treat the water in Storage Tank No. 1 for discharge to the river under
the plant's NPDES permit that includes limits for pH, TSS, total
residual chlorine, and aluminum.

Final Remediation Goal: To be conservative, the final remediation goal
for cyanide is set at 0.14 ppm (NPDES Water Quality Criteria) to be
protective of both human and ecological receptors. This concentration
must be met at the discharge.

Development and Screening of Remedial Alternatives: The team identifies
a list of candidate remedial options (alternatives) (from Whelton et
al., 2003):

-   No action

-   Chlorination using hypochlorite and caustic

-   Reverse osmosis

-   Ion exchange

-   Conventional or direct filtration using an iron coagulant

-   Ozonation

-   Hydrolysis

-   Aeration

-   Boiling

The "no action" alternative is ruled out because the rapid risk
assessment indicates there would be unacceptable risks to humans and
ecological receptors if the water were discharged from the tank
untreated. Conventional or direct filtration using iron coagulation is
ruled out because, while theoretically effective for removal of
water-soluble cyanides, it is not a proven technology for cyanides.
Ozonation is ruled out because the reaction products when treating
cyanide are unknown (Whelton et al., 2003). Hydrolysis is ruled out due
to the large volume of water that must be treated. Aeration is ruled out
due to its relatively high energy requirements and off-gases produced.
Finally, boiling is ruled out because it is impractical due to its
relatively high energy requirements, the volume of water that must be
treated, and off gases produced.

From the screening process, the team identifies three alternatives:

(1) Chlorination using hypochlorite and caustic,

(2) Reverse osmosis, and

(3) Ion exchange.

Based on engineering knowledge and extensive literature documenting the
effectiveness, implementability, and costs of these technologies, the
team determines there is no need to conduct a Treatability Study.

Comparative Analysis of Alternatives

The comparative analysis of alternative is summarized in the following
table:

+-----------------+-----------------+-----------------+-----------------+
| **Remedy        | **Alternative   | **Alternative   | **Alternative   |
| Evaluation      | 1: Chlorination | 2: Reverse      | 3: Ion          |
| Criteria**      | (Hypochlorite & | Osmosis**       | Exchange**      |
|                 | Caustic)**      |                 |                 |
+-----------------+-----------------+-----------------+-----------------+
| Overall         | Reduces CN^-^   | Reduces CN^-^   | Reduces CN^-^   |
| protection of   | concentrations  | concentrations  | concentrations  |
| human health    | to less than    | to less than    | to less than    |
| and environment | MCL, which is   | MCL, which is   | MCL which is    |
|                 | protective of   | protective of   | protective of   |
|                 | human health;   | human health;   | human health;   |
|                 | and reduces     | and reduces     | and reduces     |
|                 | concentrations  | concentrations  | CN^-^           |
|                 | to WQC, which   | to WQC, which   | concentrations  |
|                 | is protective   | is protective   | to WQC, which   |
|                 | of the          | of the          | is protective   |
|                 | environment     | environment.    | of the          |
|                 |                 |                 | environment     |
|                 |                 |                 |                 |
|                 |                 |                 | However,        |
|                 |                 |                 | discharge will  |
|                 |                 |                 | have elevated   |
|                 |                 |                 | levels of       |
|                 |                 |                 | chloride from   |
|                 |                 |                 | ion exchange    |
|                 |                 |                 | resin           |
+-----------------+-----------------+-----------------+-----------------+
| Compliance with | Would meet MCL  | Would meet MCL  | Would meet MCL  |
| regulations     | and WQC at      | and WQC at      | and WQC at      |
|                 | point of        | point of        | point of        |
|                 | discharge       | discharge       | discharge       |
+-----------------+-----------------+-----------------+-----------------+
| Long-term       | Treatment is    | Treatment is    | Treatment is    |
| effectiveness   | irreversible    | permanent, and  | permanent and   |
| and permanence  | and, no         | no untreated    | no untreated    |
|                 | untreated water | water or waste  | water or waste  |
|                 | or waste would  | would be left   | would be left   |
|                 | be left on      | on site.        | on site.        |
|                 | site.           |                 |                 |
+-----------------+-----------------+-----------------+-----------------+
| Reduction in    | Treatment       | Treatment is    | Treatment is    |
| toxicity and    | effectively     | effective in    | effective in    |
| mobility        | destroys        | reducing        | reducing        |
|                 | cyanide but     | toxicity by     | toxicity by     |
|                 | must be         | contaminant     | contaminant     |
|                 | performed at pH | removal (not    | removal (not    |
|                 | \>10 or         | destruction)    | destruction)    |
|                 | effectiveness   |                 |                 |
|                 | could be        |                 |                 |
|                 | reduced or      |                 |                 |
|                 | result in       |                 |                 |
|                 | formation of    |                 |                 |
|                 | cyanogen        |                 |                 |
|                 | chloride (a     |                 |                 |
|                 | highly toxic    |                 |                 |
|                 | substance)      |                 |                 |
+-----------------+-----------------+-----------------+-----------------+
| Generation of   | No solid or     | Highly          | Waste resin     |
| residuals       | liquid waste    | concentrated    | containing      |
|                 | residuals from  | brine           | cyanide         |
|                 | treatment.      |                 |                 |
|                 | Reaction of     |                 |                 |
|                 | hypochlorite    |                 |                 |
|                 | with CN         |                 |                 |
|                 | generates       |                 |                 |
|                 | intermediate    |                 |                 |
|                 | product         |                 |                 |
|                 | cyanate, which  |                 |                 |
|                 | is then reduced |                 |                 |
|                 | to nitrogen,    |                 |                 |
|                 | carbon dioxide, |                 |                 |
|                 | and water.      |                 |                 |
+-----------------+-----------------+-----------------+-----------------+
| Short-term      | No risks to the | No risks to     | No risks to     |
| effectiveness   | community.      | community.      | community.      |
|                 |                 |                 |                 |
|                 | Risks to        | Risks to        | Risks to        |
|                 | on-site workers | on-site workers | on-site workers |
|                 | posed by        | posed by        | posed by        |
|                 | handling of     | handling of     | handling of     |
|                 | treatment       | residuals.      | residuals.      |
|                 | chemicals       |                 |                 |
+-----------------+-----------------+-----------------+-----------------+
| I               | Technology      | Technology      | Technology      |
| mplementability | readily         | readily         | readily         |
|                 | available.      | available.      | available.      |
|                 |                 |                 |                 |
|                 | Minimal         | Specialized     | Specialized     |
|                 | specialized     | equipment       | equipment       |
|                 | equipment       | required.       | required.       |
|                 | required.       |                 |                 |
|                 |                 | Discharge       | Discharge       |
|                 | Discharge       | permit may need | permit may need |
|                 | permit may need | to be modified  | to be modified  |
|                 | to be modified  |                 |                 |
+-----------------+-----------------+-----------------+-----------------+
| Relative Cost   | Low             | High            | Medium          |
+-----------------+-----------------+-----------------+-----------------+
| State, Support  | Preferred by    | Acceptable to   | Acceptable to   |
| Agency, and     | utility, State, | State and EPA   | State and EPA   |
| Community       | EPA, and        |                 |                 |
| Acceptance      | community       |                 |                 |
+-----------------+-----------------+-----------------+-----------------+

Remedy Selection

Day 7: Based on the comparative analysis of alternatives, chlorination
at elevated pH is selected as the final remedy due to its
protectiveness, ease of implementation, and relatively low cost. In
addition, the utility is familiar and comfortable with the technology. A
public meeting and press conference are held to explain the selection of
the remedy.

Remedial Design and Remedial Action

Day 8 through 14: Engineers from the remediation and recovery team
develop specifications for the chlorination system in the form of a
Remedial Design Work Plan. The plan takes into account the schedule for
completion of the remedy, the final remediation goal, the volume of
water to be treated, expected concentrations of cyanide, piping and
other hardware required, chemicals and reagents required, utilities
required (e.g., phone lines and electrical), and site preparation.

Day 18: A trailer-mounted chlorination system that meets all remedial
design specifications is mobilized to the site, tested, and placed in
full-scale service.

Day 70: The walls of the empty Storage Tank No. 1 are washed with a
solution of sodium hypochlorite to ensure complete decontamination of
the tank.

Post-Remediation Monitoring and Return to Normal Operations

During the treatment of the contaminated water, the treated water is
held is a holding tank until analytical results confirm the remediation
goal is attained and other discharge permit limits are met. Cyanogen
chloride is also sampled, but not detected in the treated water.

Following the remedial action, a set of samples is collected from
segments of the distribution system that were served by Storage Tank No.
1 and analyzed for total cyanide, free cyanide, and cyanogen chloride.
All samples are negative for the target analytes.

Day 90: The public is advised through various media that the drinking
water treatment plant has resumed normal operations and that the
remediation has been successful. Post-remediation monitoring is ceased.

[^1]: Agencies listed in the NCP include: United States Coast Guard,
    FEMA, the Department of Defense, the Department of Energy, the
    United States Department of Agriculture, the Department of Commerce,
    HHS, the Department of Interior, DOJ, the Department of Labor, the
    Department of Transportation, the Department of State, Nuclear
    Regulatory Commission, and General Services Administration.

[^2]: These criteria are modeled after US EPA's risk and remediation
    goals found in the NCP, 40 CFR Part 300.430(e).