Office of Inspector General 

Audit Report 

WATER 

Colorado Water Quality Standards,

Monitoring, and Reporting Program

Report No. E1HWF8-07-0004-9100093

March 10, 1999
Inspector General Division Central Audit Division

 Conducting the Audit: Kansas City, Kansas

Region Covered: Region 8

Program Office Involved: Office of Ecosystems Protection

 and Remediation
March 10, 1999

MEMORANDUM

SUBJECT: Colorado’s Water Quality Standards, Monitoring, and Reporting

Audit Report E1HWF8-07-0004-9100093

FROM: Bennie S. Salem

Divisional Inspector General

TO: William P. Yellowtail

Regional Administrator

Region 8

Attached is our report entitled Colorado’s Water Quality Standards, Monitoring, and

Reporting. We discussed our findings with your staff and issued a draft report. We summarized

your comments in the final report and included your complete response in Appendix I. 

ACTION REQUIRED

In accordance with Environmental Protection Agency (EPA) Order 2750, you, as the

action official, are required to provide this office a written response to the audit report within 90

days of the final audit report date. For corrective actions planned but not completed by the

response date, reference to specific milestone dates will assist in deciding whether to close this

report. 

We appreciate the cooperation your staff provided throughout the audit. We especially

appreciate the program staff's assistance and cooperation during the audit. The staff exhibited a

genuine interest in working with us to improve the water quality program and helped add value to

this audit. 

This audit report contains findings that the Office of Inspector General (OIG) has

identified and corrective actions OIG recommends. This audit report represents the opinion of

OIG, and the findings in this audit report do not necessarily represent the final EPA position. 

Final determinations on matters in this audit report will be made by EPA managers in accordance

with established EPA audit resolution procedures. 

We have no objections to the release of this report to the public. If you have any

questions, please call Connie Walton, Audit Manager, at (913) 551-7007. Please refer to report

number E1HWF8-07-0004-9100093 on any correspondence.

Attachment
Colorado Water Quality Standards,

Monitoring, and Reporting Program

i Report No. E1HWF8-07-0004-9100093

EXECUTIVE SUMMARY

INTRODUCTION Water is one of our vital resources and must be protected. 

One of the Environmental Protection Agency’s (EPA) 10

strategic goals is for clean and safe water. This goal

includes ensuring our surface waters, such as lakes, rivers,

wetlands, and oceans sustain human health, support and

maintain aquatic life, and provide for both recreational and

economic activities. EPA and states developed water

quality programs to protect surface waters by identifying

how the water is to be used, setting standards to meet the

use, and then monitoring and reporting on how well the

water quality supports the use. EPA and states use their

water quality information as a basis for, and to measure

performance of, their programs to control and clean up

water pollution. This audit is one in a series of state water

quality audits conducted by the Office of Inspector General

(OIG) to develop a national picture of the performance of

state water quality programs.

OBJECTIVES Our overall objective was to determine whether Colorado’s

water quality program effectively protects its surface water

to sustain human health and aquatic life, and provides for

both recreational and economic activities. Our specific

objectives were to answer the following questions:

P Has Colorado implemented procedures to

develop water quality standards that will

protect the State’s water quality?

P Has Colorado implemented procedures to

test and assess the quality of all appropriate

waters in the State?

P Are State reports on water quality complete,

accurate, and useful for program

management?
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Monitoring, and Reporting Program

ii Report No. E1HWF8-07-0004-9100093

P Has Region 8 implemented effective

procedures to approve Colorado water

quality standards and evaluate the State’s

water quality standards setting, testing,

assessing, and reporting?

RESULTS IN BRIEF Overall, Colorado developed a water quality program that

generally protects its surface water to sustain human health

and aquatic life, and provides for recreational and economic

activities. Colorado implemented procedures to develop

comprehensive water quality standards to protect State

water quality. However, in implementing any program as

complex as the Clean Water Act, improvements can be

made in adopting and supporting decisions for water quality

standards. Colorado’s monitoring program employed

appropriate monitoring methods and procedures to 

evaluate the waters of the State; although, like other states,

Colorado has faced difficult challenges in maintaining a

comprehensive water quality monitoring program. 

Colorado water quality reports varied in completeness and

accuracy.

Region 8 priorities in the oversight of the Colorado water

quality program reflected the Office of Water priorities. 

Region 8 oversight efforts focused on the development of

standards while placing little emphasis on Colorado’s

monitoring activities. Region 8 implemented effective

procedures to approve and evaluate Colorado’s water

quality standards setting; however, it had not developed

procedures to oversee and evaluate Colorado’s water

quality testing, assessing, and water quality assessment

reporting. Colorado, in turn, historically has placed more

attention on the development of its standards program than

on monitoring, assessing, and reporting activities. 
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Monitoring, and Reporting Program

iii Report No. E1HWF8-07-0004-9100093

RECOMMENDATIONS We recommend the Regional Administrator:

P Work with Colorado to improve its support

for water quality standards decisions and

disapprove future water quality standards

submissions which lack adequate analysis

and support.

P Assist Colorado in increasing the

comprehensiveness of its state water quality

monitoring program.

P Persuade Colorado to follow national

guidance in preparing the water quality

assessment report to include complete,

accurate information.

P Develop procedures to oversee and evaluate

Colorado’s water quality testing, assessing,

and water quality assessment reporting. 

AGENCY AND STATE

COMMENTS AND

OIG EVALUATION

Region 8 and Colorado generally agreed with the

recommendations. Region 8 agreed that coordinated work

with the State is needed for continued program

improvements. Region 8 documented several planned

technical and program support activities and commitments

to work with and support Colorado programs. Colorado

welcomed assistance in its ongoing efforts to continually

enhance water quality testing, assessing, and water quality

assessment reporting.
Colorado Water Quality Standards,

Monitoring, and Reporting Program

TABLE OF CONTENTS

Page

EXECUTIVE SUMMARY .................................................... i

CHAPTERS

1 INTRODUCTION ..................................................... 1

PURPOSE ..................................................... 1

BACKGROUND ................................................ 2

SCOPE AND METHODOLOGY ................................... 5

PRIOR AUDIT COVERAGE ...................................... 5

2 ALTHOUGH COLORADO’S STANDARDS PROGRAM IS STRONG, 

ADDITIONAL STANDARDS AND MORE SUPPORT FOR DECISIONS ARE

NEEDED ............................................................ 6

COLORADO DEVELOPED AND ADOPTED CRITERIA WHERE EPA 

HAD NOT ..................................................... 7

COLORADO DID NOT ADOPT THE NATIONAL SWIMMABLE USE

CLASSIFICATION FOR ALL STATE WATERS ....................... 8

COLORADO SHOULD ADOPT CLEAN WATER ACT CRITERIA

FOR ALL WATERS CLASSIFIED TO PROVIDE DRINKING WATER ..... 9

COLORADO COULD BETTER SUPPORT CRITERIA LIMITS FOR

POLLUTANTS ................................................ 10

CONCLUSION ................................................ 11

RECOMMENDATIONS ......................................... 12

AGENCY AND STATE COMMENTS AND OIG EVALUATION ......... 12

3 PROGRESS IN COLORADO’S MONITORING PROGRAM IS STILL POSSIBLE . 14

STATES MUST ESTABLISH APPROPRIATE TESTING .............. 14
Colorado Water Quality Standards,

Monitoring, and Reporting Program

COLORADO’S MONITORING PROGRAM IS EVOLVING ............. 14

COLORADO COULD UTILIZE MORE ADVANCED MONITORING

TECHNIQUES ................................................ 15

FORMAL PROCESS TO OBTAIN ORGANIC MONITORING DATA 

WOULD IMPROVE WATER QUALITY ASSESSMENTS .............. 15

CONCLUSION ................................................ 16

RECOMMENDATIONS ......................................... 16

AGENCY AND STATE COMMENTS AND OIG EVALUATION ......... 16

4 COLORADO’S EMPHASIS ON WATER QUALITY REPORTS WAS

INCONSISTENT .................................................... 17

STATES MUST REPORT ON QUALITY OF THEIR WATERS ......... 17

COLORADO’S IMPAIRED WATERBODY LIST APPEARED TO BE

COMPLETE AND ACCURATE ................................... 18

COLORADO’S WATER QUALITY ASSESSMENT REPORT WAS

NOT COMPLETE OR ACCURATE ................................ 18

ASSESSMENT DATABASE COULD IMPROVE STATE PROCESSES .... 19

CONCLUSION ................................................ 19

RECOMMENDATIONS ......................................... 20

AGENCY AND STATE COMMENTS AND OIG EVALUATION ......... 20

5 REGION 8 OVERSIGHT MIRRORED OFFICE OF WATER DIRECTION ....... 21

WATER MANAGEMENT AGREEMENT LISTS PRIORITIES AND

MEASURES .................................................. 21

REGION 8 ACTIVELY PARTICIPATED IN COLORADO’S

STANDARDS PROGRAM ....................................... 22

REGION 8 HAD LIMITED INVOLVEMENT IN COLORADO’S

MONITORING PROGRAM ...................................... 22
Colorado Water Quality Standards,

Monitoring, and Reporting Program

CONCLUSION ................................................ 22

RECOMMENDATIONS ......................................... 23

AGENCY AND STATE COMMENTS AND OIG EVALUATION ......... 23

EXHIBITS

1 SCOPE AND METHODOLOGY ........................................ 24

APPENDICES

I AGENCY RESPONSE ................................................ 26

II STATE RESPONSE .................................................. 38

III ABBREVIATIONS ................................................... 49

IV DISTRIBUTION ..................................................... 50
Colorado Water Quality Standards,

Monitoring, and Reporting Program

1 Report No. E1HWF8-07-0004-9100093

CHAPTER 1

INTRODUCTION

PURPOSE Water is one of our vital resources and must be protected. 

One of the Environmental Protection Agency’s (EPA) 10

strategic goals is for clean and safe water. This goal

includes ensuring our surface waters, such as lakes, rivers,

wetlands, and oceans sustain human health, support and

maintain aquatic life, and provide for both recreational and

economic activities. EPA and states developed water

quality programs to protect surface waters by identifying

how the water is to be used, setting standards to meet the

use, and then monitoring and reporting on how well the

water quality supports the use. EPA and states use their

water quality information as a basis for, and to measure

performance of, their programs to control and clean up

water pollution. 

This audit is one in a series of state water quality audits

conducted by the Office of Inspector General (OIG) to

develop a national picture of the performance of state water

quality programs. OIG selected a variety of states where

audits could identify best practices and needed

improvements. 

Our overall objective was to determine whether Colorado’s

water quality program effectively protects its surface water

to sustain human health and aquatic life, and provides for

both recreational and economic activities. Our specific

objectives were to answer the following questions:

P Has Colorado implemented procedures to

develop water quality standards that will

protect the State’s water quality?

P Has Colorado implemented procedures to

test and assess the quality of all appropriate

waters in the State?
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2 Report No. E1HWF8-07-0004-9100093

P Are State reports on water quality complete,

accurate, and useful for program

management?

P Has Region 8 implemented effective

procedures to approve Colorado water

quality standards and evaluate the State’s

water quality standards setting, testing,

assessing, and reporting?

BACKGROUND The Clean Water Act is the primary legislation addressing

water quality programs. The Clean Water Act’s objective is

to restore and maintain the quality of the nation’s surface

waters. The Clean Water Act requires states to adopt water

quality standards. These standards are an important basis

for state actions to control and remedy water pollution. 

Water quality standards have three parts: (1) water use

classifications, (2) water quality criteria, and (3) an

antidegradation policy. 

States classify waters according to how they can be used,

such as for drinking water supply, fishing, and swimming. 

States can assign multiple use classifications to waters. The

Clean Water Act goal is that all waters of the United States

be fishable and swimmable, where attainable. The fishable

use provides for the protection and propagation of fish,

shellfish, and wildlife. The swimmable use provides for

recreation in and on the water. States are required to adopt

the fishable and swimmable use classifications for all waters,

unless the water cannot meet these uses. If the waters

cannot meet these uses, 40 Code of Federal Regulations

(CFR) 131.10, Designation of uses, requires states to

conduct special studies showing the uses are not attainable. 

Once states assign water use classifications, the Clean

Water Act requires states to adopt water quality criteria to

protect the uses. Water quality criteria identify the amount

of a specific pollutant that may be present in the water and

still protect the use. For example, the water quality criteria
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Monitoring, and Reporting Program

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for a fishable use could identify how much mercury can be

present in the water and still protect the fish and other

aquatic life. For protection of aquatic life, EPA

recommends two types of criteria - acute and chronic. 

Acute criteria are designed to protect aquatic life from

short-term exposures to pollutants, while chronic criteria

are designed to protect aquatic life from exposure to

pollutants over long periods of time. 

EPA develops and publishes criteria that set limits for

pollutants based on the effect the pollutants have on the

water use classifications. The Clean Water Act requires

EPA to develop criteria for 126 priority toxic pollutants;

i.e., the most persistent, prevalent, and toxic of pollutants. 

To date, EPA has only developed criteria for 99 of the

priority toxic pollutants. States may use EPA criteria or

develop their own scientifically defensible criteria. 

40 CFR 131.12, Antidegradation policy, requires states to

have an antidegradation policy to conserve, maintain, and

protect existing uses of waterbodies and maintain water

quality. The antidegradation policy also should protect

waters of exceptionally high quality or value.

States are required to review their water quality standards

once every 3 years and obtain EPA approval for the

standards. If EPA disapproves a state’s water quality

standards, it is required to promulgate new standards for the

state. The state’s water quality standards remain in effect

unless EPA promulgates new standards for the state. 

40 CFR 130.4, Water quality monitoring, requires states to

develop a monitoring program to assess whether state

waters meet water quality standards. State water quality

monitoring programs generate important information

necessary to guide management decisions and track

environmental progress. Monitoring programs identify

waters to be tested, frequency of testing, and types of

testing. State monitoring programs must meet EPA’s

general quality assurance requirements. 
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Monitoring, and Reporting Program

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The Clean Water Act requires each state to submit to EPA a

biennial water quality assessment report summarizing its

water quality assessments. EPA summarizes the state

reports in a national report to Congress. EPA uses the state

water quality assessments to measure performance in

achieving its goal of clean and safe water. 

If a waterbody does not meet its water quality standards,

the state classifies the waterbody as impaired and

determines the cause of impairment. Water pollution comes

from either point or nonpoint sources. Point source

discharges are controlled through the use of permits. 

Examples of point source dischargers are municipal sewage

treatment plants and industrial facilities. These types of

facilities discharge through identifiable conveyances, such as

pipes or sewers into surface waters. Nonpoint sources of

pollution are less readily identifiable, such as from

agricultural runoff. 

Once the state identifies impaired waterbodies, the state is

required to develop total maximum daily loads if existing

controls are not sufficient to correct the impairment. Total

maximum daily loads specify the amount of pollution

allowed to enter a waterbody from both point and nonpoint

sources. The Clean Water Act requires states to submit to

EPA a biennial list of its impaired waterbodies still requiring

total maximum daily loads. EPA reviews and approves the

impaired waterbody list. 

The Colorado Water Quality Control Commission and the

Colorado Department of Public Health and Environment are

responsible for protecting and maintaining Colorado’s water

quality. The Water Quality Control Commission sets

pollution control policy in Colorado. The Water Quality

Control Division within the Department of Public Health

and Environment advises the Commission on water quality

standards, monitors water quality, and reports on the status

of water quality. In fiscal 1998, EPA provided

approximately $700,000 to the Department of Public Health

and Environment for its surface water program.
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Monitoring, and Reporting Program

5 Report No. E1HWF8-07-0004-9100093

SCOPE AND

METHODOLOGY

We performed our audit in accordance with the Government

Auditing Standards (1994 revision) issued by the

Comptroller General of the United States as they apply to

program audits. Our review included tests of the program

records and other auditing procedures we considered

necessary. We conducted our fieldwork from March

through August 1998. We performed our fieldwork at

Region 8 and the Colorado Department of Public Health

and Environment, both in Denver, Colorado.

See Exhibit 1 for methodology details.

PRIOR AUDIT

COVERAGE

Although neither the OIG nor the U.S. General Accounting

Office has issued any recent reports directly related to

Colorado's water quality standards, monitoring, and

reporting program, the OIG completed a similar audit in the

State of Missouri, Missouri’s Water Quality Standards and

Monitoring, dated March 31, 1998. In this report, the OIG

recommended to the EPA Regional Administrator that

Missouri should adopt the swimmable use classification for

all waters or conduct the required studies showing the use

could not be achieved. The OIG also recommended

Missouri adopt EPA or other scientifically defensible

criteria, develop a monitoring strategy to ensure

comprehensive monitoring of all State waters, and

implement procedures and controls to ensure its water

quality reports are complete and accurate. 
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Monitoring, and Reporting Program

6 Report No. E1HWF8-07-0004-9100093

CHAPTER 2

ALTHOUGH COLORADO’S STANDARDS PROGRAM IS STRONG,

ADDITIONAL STANDARDS AND MORE SUPPORT

FOR DECISIONS ARE NEEDED

Colorado implemented procedures to develop water quality

standards that were comprehensive and protected State

water quality. However, in implementing any program as

complex as the Clean Water Act, improvements can be

made in adopting standards and supporting decisions for

those standards. Colorado water quality regulations define

the conditions for adopting standards, but do not define the

specific documentation required to support those decisions. 

Colorado needs to ensure that its decisions are supported

with sufficient scientific analysis. In the absence of this

analysis, policy-making bodies in Colorado make decisions

based on incomplete information. Without adequately

justifying decisions to adopt water quality standards, the

public and aquatic life could be exposed to unsafe levels of

pollution and the public could face increased health risks.

Colorado developed water quality criteria for pollutants in

the absence of EPA criteria to make certain its citizens were

protected against dangerous pollutants found in State

waters. However, Colorado standards could be improved

by addressing the following issues:

P Colorado did not adopt the national

swimmable use classification for all of its

waters, nor provide support that the use

could not be met. 

P Colorado could increase protection of

waterbodies used for drinking water supply

by adopting all Clean Water Act human

health criteria. 

P Colorado adopted criteria for several

pollutants based on the amount of pollution
Colorado Water Quality Standards,

Monitoring, and Reporting Program

7 Report No. E1HWF8-07-0004-9100093

in the water without supporting that the

waters’ use was still protected. 

COLORADO

DEVELOPED AND

ADOPTED CRITERIA

WHERE EPA

HAD NOT

Colorado has a well-developed water quality standards

program. Colorado adopted water quality criteria for more

than 140 pollutants and has been proactive in developing

water quality criteria for toxic pollutants where EPA had

not. For example, Colorado developed scientifically

defensible criteria for silver and the organic pollutant

diisopropylmethylphosphonate (DIMP). Colorado felt that

these pollutants could threaten both human health and

aquatic life, and therefore developed criteria to protect its

waters from these pollutants.

The Clean Water Act charged EPA with developing water

quality criteria for priority pollutants to protect human

health and aquatic life. Federal regulations place the

responsibility on states to adopt water quality criteria to

protect water use classifications where EPA has not

developed criteria. 

Colorado developed chronic aquatic life criteria for silver

because silver is dangerous to aquatic life. Although EPA

recommends both acute and chronic criteria for aquatic life,

it only developed acute aquatic life criteria for silver. 

Colorado officials believed chronic criteria was needed to

protect aquatic life and developed its own scientifically

defensible chronic criteria. Colorado resisted attempts by a

strong industry lobby group to overturn the decision to

adopt the chronic silver criteria. 

Colorado also developed water quality criteria for DIMP to

protect waters used for drinking water supply. Colorado

found DIMP leaching into drinking water supply waters

near the Colorado Rocky Mountain Arsenal. Colorado

officials believed that this pollutant was harmful to human

health. In the absence of EPA-published criteria to limit

DIMP, Colorado developed and adopted its own

scientifically defensible criteria for this organic pollutant. 
Colorado Water Quality Standards,

Monitoring, and Reporting Program

8 Report No. E1HWF8-07-0004-9100093

As a result, Colorado now protects its drinking water

supplies from the potential effects of DIMP. 

COLORADO DID NOT

ADOPT THE NATIONAL

SWIMMABLE USE

CLASSIFICATION FOR

ALL STATE WATERS

Colorado did not adopt the national swimmable use

classification for all State waters. The Clean Water Act

requires states to adopt the swimmable use classification for

every waterbody, where attainable. Colorado did not follow

its own policy in adopting the swimmable use classification, 

nor did the State provide acceptable special studies

supporting that the use was not attainable. Without the

swimmable use classification, Colorado allows bacteria to

be present in waters used for recreational activities at higher

levels than it and EPA consider safe for human contact.

Colorado did not follow its own policy in adopting the

swimmable use classification. Colorado’s policy is to adopt

the swimmable use classification for waters used for

recreational activities that involve the possibility of ingesting

small quantities of water; for example, kayaking and rafting. 

We identified several waters where Colorado had evidence

of other recreational activities such as non-motorized travel

and occasional wading but did not adopt the swimmable use

classification. We believe kayaking and rafting are forms of

non-motorized travel, and small children could ingest small

quantities of water when wading. Colorado did not adopt

the swimmable use classification for 257 of its 603

waterbodies (43 percent). We reviewed 45 of these 257

waterbodies and found that 16 were used for these other

types of recreational activities. While current monitoring of

the 16 waterbodies did not show evidence of unsafe levels

of bacteria, proper use classifications ensure safe bacteria

limits are in place to protect human health. 

Colorado did not provide acceptable special studies

supporting that the swimmable use was not attainable. 

Federal regulations acknowledge that the swimmable use

may not always be attainable and provide an exception

where states conduct special studies supporting their

decision. However, federal regulations are silent as to the
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Monitoring, and Reporting Program

9 Report No. E1HWF8-07-0004-9100093

minimum requirements of the special studies. Colorado

officials disagreed with Region 8 over the contents of the

special studies. Colorado officials believed a simple

description of the water segment met the requirements of

the study and claimed they met the requirements. Region 8

officials, however, believed that the special studies should

include more rigorous analysis of the water condition. 

Region 8 repeatedly requested the State to conduct the

studies and provided examples. 

COLORADO SHOULD

ADOPT CLEAN WATER

ACT CRITERIA FOR ALL

WATERS CLASSIFIED

TO PROVIDE DRINKING

WATER

Ambiguous EPA national guidance resulted in inconsistent

adoption of criteria for Colorado waterbodies classified to

provide drinking water. Colorado adopted drinking water

supply criteria for all pollutants specified in the Safe

Drinking Water Act. However, EPA developed criteria for

other pollutants for the protection of human health under

the Clean Water Act, but did not require states to adopt

these criteria for waterbodies used for drinking water. As a

result of Colorado following national guidance, 42

waterbodies in Colorado classified for drinking water supply

had fewer criteria for pollutants than other State

waterbodies classified to provide drinking water to the

Colorado public. 

The Clean Water Act requires states to adopt water quality

criteria for priority pollutants if the presence of the pollutant

could interfere with the uses of the waterbody. The Safe

Drinking Water Act established maximum pollutant levels,

or criteria, that control toxic chemicals coming out of the

tap. According to EPA’s Water Quality Standards

Handbook, when setting water quality criteria for public

water supplies, states have the option of applying the Safe

Drinking Water Act criteria, the Clean Water Act criteria,

or more stringent controls to protect against the effects of

contaminants by ingestion from drinking water. 

Unfortunately, EPA did not develop criteria for all of the

same pollutants under the Clean Water Act and Safe

Drinking Water Act. Therefore, although Colorado

adopted criteria for drinking water supplies for all pollutants
Colorado Water Quality Standards,

Monitoring, and Reporting Program

10 Report No. E1HWF8-07-0004-9100093

with Safe Drinking Water Act criteria, it did not adopt

EPA-recommended criteria for other pollutants identified by

the Clean Water Act.

COLORADO COULD

BETTER SUPPORT

CRITERIA LIMITS FOR

POLLUTANTS

Colorado adopted water quality criteria for some pollutants

in certain waters that were less restrictive than the criteria

applied to most other waters in the State. For these

pollutants, Colorado did not provide support showing the

criteria were still protective of the uses for the waters. 

Colorado names this form of criteria ambient-based criteria,

which refers to the amount of the pollutant already present

in the water. Ambient-based criteria are less restrictive than

EPA-recommended criteria; therefore, Colorado allows

more pollutants in waters where ambient-based criteria are

adopted. Colorado could not support its claim that allowing

more pollution in some of its waters was still protective of

the waters’ use. 

Colorado has not always provided adequate support for its

ambient-based criteria. We reviewed 14 of the 109 waters

with ambient-based criteria and found Colorado did not

have adequate support that the less restrictive criteria still

protected the waters’ use. In the waters reviewed,

Colorado generally relied on monitoring results as sufficient

support for adoption of ambient-based criteria. 

Colorado regulations allow for adopting ambient-based

criteria where natural or irreversible man-induced water

quality levels are higher than Colorado’s generally accepted

criteria. The adoption of ambient-based criteria is an

alternative to downgrading or removing a use associated

with a particular waterbody. Because of its geography,

Colorado has naturally high concentrations of metals in

many parts of the State. Colorado officials also believe that

man-induced practices, such as past mining activities, have

irreversibly disturbed some waters. Region 8 concurs that 

ambient-based criteria may be appropriate in these types of

waters but should be properly supported.
Colorado Water Quality Standards,

Monitoring, and Reporting Program

11 Report No. E1HWF8-07-0004-9100093

Region 8 questioned Colorado’s lack of support for specific

ambient-based criteria for several years. Regional staff

commented on draft and proposed ambient-based criteria,

and urged Colorado to document a technically-defensible

rationale for ambient-based criteria. In August 1998, 

Region 8 disapproved Colorado’s ambient-based criteria for

certain portions of the Animas River because Colorado did

not provide support that the criteria was protective of the

waters’ existing use. 

Although all of Colorado’s water quality standards

decisions are made in a public forum, the written

justification needed to adopt standards is only that necessary

to convince a majority of the Water Quality Control

Commissioners. When making recommendations to the

Commission, the Water Quality Control Division does not

always provide adequate supporting documentation for

those recommendations. In order to ensure that State water

is protective of the waters’ uses, the Water Quality Control

Division should provide sufficient support showing that its

recommendations will continue to maintain and protect

Colorado’s water quality.

CONCLUSION Colorado has a well-developed water quality standards

program. Colorado has adopted water quality criteria for

more than 140 pollutants, and has developed criteria on its

own when it felt that a pollutant could interfere with the

uses of its water and pose a threat to both human and

aquatic life. Like any complex environmental program,

however, improvements are possible. Ensuring waters

remain safe for swimming is important because people will

use whatever waters are available for recreation. Maximum

protection for waters used as drinking water sources is a

must to help ensure the water we use in our homes is free

from dangerous pollutants. When Colorado adopts

ambient-based criteria without adequate support, it may

send a message to the regulated community that this type of

criteria may be acceptable for any waters where elevated

concentrations of pollutants can’t be easily explained.
Colorado Water Quality Standards,

Monitoring, and Reporting Program

12 Report No. E1HWF8-07-0004-9100093

RECOMMENDATIONS We recommend the Regional Administrator:

2-1. Work with Colorado to adopt the national

swimmable use classification and

corresponding criteria limits where

attainable, or conduct the required special

studies with consideration of basinwide

special studies. Disapprove Colorado water

quality standard submissions which do not

comply with these options.

2-2. Work with Office of Water to remove the

ambiguity in national guidance for adopting

drinking water supply criteria, and

recommend Colorado adopt the Clean Water

Act human health based criteria for all State

waters classified for drinking water supplies.

2-3. Continue to encourage Colorado to develop

written justification supporting the

appropriateness of adopting ambient-based

criteria and disapprove water quality

standards submissions that include

inadequate analysis.

AGENCY AND STATE

COMMENTS AND OIG

EVALUATION

Colorado provided comments to clarify portions of the

report, and we have incorporated these comments and

modified the report as appropriate. 

Region 8 agreed with recommendation 2-1 and stated

additional work is needed at the Regional and State level to

bring Colorado into compliance with federal requirements

for the protection of the swimmable use. Colorado did not

agree to adopt the national swimmable use classification and

corresponding criteria limits for all waters, where attainable. 

Colorado did not provide the required special studies

supporting that the swimmable use was not attainable. 
Colorado Water Quality Standards,

Monitoring, and Reporting Program

13 Report No. E1HWF8-07-0004-9100093

However, Colorado stated more documentation was

desirable to support decisions regarding adoption of

recreational use classifications. Thus, Region 8 will need to

disapprove these standards. 

Region 8 agreed with recommendation 2-2, that there is

ambiguity in national guidance for adopting drinking water

supply criteria and will continue to discuss this issue with

Office of Water. However, Region 8 believes Colorado

adopted sufficient criteria to protect its drinking water

supplies, though not the most protective of the several

acceptable approaches established by EPA, and did not

agree to recommend a change. Colorado adopted all Safe

Drinking Water Act criteria; however, it did not agree to

also adopt Clean Water Act criteria designed to protect

human health for all state waters classified for drinking

water supply.

Region 8 agreed with recommendation 2-3 that additional

work was needed at the Regional and State level to improve

the process by which ambient-based standards are

developed and adopted. Colorado agreed more

documentation was desirable to support decisions, including

preparing analyses at triennial reviews for maintaining

ambient standards in light of changed conditions since the

initial standards adoption. 
Colorado Water Quality Standards,

Monitoring, and Reporting Program

14 Report No. E1HWF8-07-0004-9100093

CHAPTER 3

PROGRESS IN COLORADO’S MONITORING PROGRAM

IS STILL POSSIBLE

Colorado’s current monitoring program employed

appropriate monitoring methods and procedures to test and

assess the waters of the State. Colorado, like other states,

has faced difficult challenges in maintaining a

comprehensive water quality monitoring program. In 1997,

Colorado reorganized to create a new monitoring unit, and

thus demonstrated the State’s increased commitment to

water quality monitoring. However, Colorado could utilize

more advanced monitoring techniques and needs to develop

a formal process to obtain organic monitoring data. 

Without organic monitoring data, Colorado may not be able

to identify all impaired waters.

STATES MUST

ESTABLISH

APPROPRIATE 

TESTING

40 CFR 130.4, Water quality monitoring, requires states to

establish appropriate testing techniques to monitor water

quality. This monitoring information is to be used to

support activities to abate and control pollution, develop

water quality standards, and report water quality

information to the public. The regulations further require

that water monitoring programs include the collection and

analysis of physical, chemical, and biological data, and

quality assurance and control programs to assure

scientifically valid data.

COLORADO’S

MONITORING

PROGRAM IS

EVOLVING

Colorado, like other states, has faced difficult challenges in

maintaining a comprehensive water quality monitoring

program. In 1995, Colorado exhausted all means of

supporting instream water quality monitoring. However, in

1995, Colorado directed additional resources toward

watershed scale monitoring. In 1997, Colorado reorganized

to create a monitoring unit and significantly reallocated staff
Colorado Water Quality Standards,

Monitoring, and Reporting Program

15 Report No. E1HWF8-07-0004-9100093

resources targeted to monitoring. As a result, Colorado’s

current monitoring program more comprehensively

identifies waters to be tested and ensures frequent testing of

the waters. 

COLORADO COULD

UTILIZE MORE

ADVANCED

MONITORING

TECHNIQUES

The overall usefulness of Colorado’s monitoring in its

various watersheds would improve with a more wellrounded monitoring design, including biological indicators. 

Colorado’s monitoring program primarily conducted

chemical-specific water quality testing in the last 2 years. 

Chemical-specific testing alone does not provide the

necessary information to determine the biological condition

of the water. Skewed emphasis on chemical testing could

result in the State not identifying impaired waters. 

Colorado’s monitoring has included more advanced

monitoring techniques such as ambient toxicity testing, fish

population estimates, macro invertebrate surveys, and

habitat assessments. However, the extent of these more

advanced monitoring techniques was limited. Additional

monitoring data would provide Colorado with a better basis

for determining the effectiveness of its water management

program and the answer to the question: What is the

condition of state waters? 

FORMAL PROCESS TO

OBTAIN ORGANIC

MONITORING DATA

WOULD IMPROVE

WATER QUALITY

ASSESSMENTS

Colorado had no systematic process to obtain organic

pollutant monitoring data for use in water quality

assessments and reporting. Organic pollutants, such as

pesticides and herbicides, can pose a threat to human health

and aquatic life. Colorado Water Quality Control Division’s

monitoring program did not include testing State waters for

organic pollutants. Although other Colorado divisions and

federal agencies tested the waters for organic pollutants, the

Water Quality Control Division did not have a structured

process for obtaining and using this testing data. Without

these testing results, Colorado cannot identify waters

impaired by organic pollutants.
Colorado Water Quality Standards,

Monitoring, and Reporting Program

16 Report No. E1HWF8-07-0004-9100093

CONCLUSION Although Colorado’s monitoring program met statutory

requirements, the State is interested in increasing the extent

of more advanced monitoring techniques. Colorado

officials stated funding constraints limited their ability to

expand their monitoring program. Also, Colorado could

provide for a more comprehensive evaluation of water

impairments by obtaining organic pollutant monitoring data

or monitoring the waters themselves.

RECOMMENDATIONS We recommend the Regional Administrator:

3-1. Provide technical assistance to help

Colorado formulate a long range plan to

expand its monitoring program to include

advanced testing techniques. 

3-2. Request that Colorado develop and

implement a process to obtain and use other

sources of organic pollutant monitoring or

monitor for organic pollutants themselves.

AGENCY AND STATE

COMMENTS AND OIG

EVALUATION

Region 8 agreed with both recommendations. Colorado

welcomed both technical assistance from Region 8 toward

improving its monitoring program, and ideas on better

means to incorporate organic chemical monitoring data into

water quality assessments.
Colorado Water Quality Standards,

Monitoring, and Reporting Program

17 Report No. E1HWF8-07-0004-9100093

CHAPTER 4

COLORADO’S EMPHASIS ON WATER QUALITY

REPORTS WAS INCONSISTENT

Colorado water quality reports varied in completeness and

accuracy. EPA and public pressures brought on in part by

recent total maximum daily load lawsuits prompted

Colorado to accurately prepare the impaired and threatened

waterbodies list. However, Colorado had not felt similar

pressure from EPA and the public to focus on the quantity

and quality of data included in the water quality assessment

report, the primary mechanism to report to the public on the

quality of its waters. Also, Colorado did not use a database

to store water quality assessments to increase the efficiency

of its water quality reporting. Colorado’s lack of emphasis

on the preparation of the water quality assessment report

may result in Congress and the public using inaccurate or

incomplete data for decision making. 

STATES MUST REPORT

ON QUALITY OF

THEIR WATERS

Clean Water Act section 303(d) requires states to list

impaired waterbodies. The impaired waterbody list is used

to schedule waterbodies for the development of total

maximum daily loads. 40 CFR 130.7, Total maximum daily

loads (TMDL) and individual water quality-based effluent

limitations, requires states to identify all impaired

waterbodies where existing pollution control requirements

are not stringent enough to achieve the water quality

standards. 

Clean Water Act section 305(b) requires states to submit a

report describing the quality of all waters within the state

every 2 years. 40 CFR 130.8, Water quality report,

provides that the water quality assessment reports serve as

the primary assessment of state water quality and provide

the basis for water quality management planning. EPA,

states, and tribes together developed guidance for the

preparation of this report. The goal of the guidance is to
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18 Report No. E1HWF8-07-0004-9100093

improve the accuracy, consistency, and usefulness of water

quality data reported by the states, and then summarized in

the national report on water quality for Congress and the

public. 

COLORADO’S

IMPAIRED

WATERBODY LIST

APPEARED TO BE

COMPLETE AND

ACCURATE

Colorado appeared to develop a complete and accurate

impaired and threatened waterbody list. Colorado placed a

high priority on the preparation of this list and implemented

effective procedures to develop the list. Colorado’s

emphasis on preparation of the list stemmed in part from

recent lawsuits that focused increased public attention on

the accuracy of the lists. Further, Colorado used the list as

a tool to develop monitoring plans, direct program efforts,

and prioritize the development of total maximum daily

loads. 

COLORADO’S WATER

QUALITY ASSESSMENT

REPORT WAS NOT

COMPLETE OR

ACCURATE

Although Colorado recognized the importance of the water

quality assessment report as a public information vehicle,

the report was not complete or accurate, and therefore not

comparable to other states. Colorado’s 1996 water quality

assessment report did not include tables of the status of

water quality by use classification. Further, Colorado

inappropriately made presumed assessments of water quality

for organic pollutants. As a result, Colorado’s 1996

assessment report cannot be accurately compiled with other

state reports to present a national picture of water quality.

Colorado did not follow specific recommendations in the

national guidance document. Colorado did not prepare

tables of all use classifications in the report as

recommended. These tables would have shown the number

of river miles and lake acres for each use classification in

Colorado, and which waters were fully, partially, or not

supporting their use. The tables also would have shown

which waters’ uses were threatened or not attainable. 

Colorado’s water quality assessment report cannot be
Colorado Water Quality Standards,

Monitoring, and Reporting Program

19 Report No. E1HWF8-07-0004-9100093

compiled with other state data to present an analysis of the

status of water quality nationwide. 

Colorado made presumed assessments by classifying

waterbodies as fully supporting in the absence of organic

pollutant monitoring data. The national guidance clearly

cautioned states against making presumed assessments and

categorizing waters as fully supporting in the absence of

monitoring data. Colorado classified all waters as fully

supporting without organic pollutant monitoring data. 

ASSESSMENT

DATABASE COULD

IMPROVE STATE

PROCESSES

Colorado could improve its reporting process and more

efficiently and effectively report water quality data to the

public by using a database to store water quality

assessments. Colorado did not meet the 1998 water quality

assessment report submittal deadline required by the Clean

Water Act because Colorado did not have an efficient

process for preparing the report. Colorado could increase

the likelihood of timely submittal of required reports and

more efficiently compile water quality assessment data by

having a database of assessments. Colorado could assess

water quality as monitoring data became available and later

review the assessments without having to recompile the

data. Also, Colorado could reduce duplication of effort by

not reassessing water quality data when preparing each of

the required reports. A database could also facilitate the

tracking and analysis of trends in water quality and

biological monitoring, which could provide a basis for

evaluating the appropriateness of numeric water quality

criteria. 

CONCLUSION Although a high emphasis was placed on the preparation of

the impaired and threatened waterbody list, Colorado could

improve the usefulness of the water quality assessment

report by consistently following national guidance. 

Consistent reporting of water quality among states enables

the aggregation of data for comparisons and analysis on a
Colorado Water Quality Standards,

Monitoring, and Reporting Program

20 Report No. E1HWF8-07-0004-9100093

national scale. Also, Colorado needs to implement a more

efficient automated process for maintaining water quality

assessment data which would assist in developing trend data

to comprehensively assess water quality changes. As a

result, Congress and the public would make decisions based

on more accurate and complete reporting data.

RECOMMENDATIONS We recommend the Regional Administrator:

4-1. Persuade Colorado to follow the national

guidance in preparing the water quality

assessment report and include complete,

accurate information.

4-2. Work with Colorado to develop a database

to maintain water quality assessment data.

AGENCY AND STATE

COMMENTS AND OIG

EVALUATION

Region 8 agreed with both recommendations. Colorado

shared concerns over inconsistent reporting of water quality

among states and committed to make ongoing progress

towards a more complete, accurate, and comprehensive

water quality assessment report. Colorado also agreed a

database to maintain water quality assessments would make

them more accessible and easier to report. 
Colorado Water Quality Standards,

Monitoring, and Reporting Program

21 Report No. E1HWF8-07-0004-9100093

CHAPTER 5

REGION 8 OVERSIGHT MIRRORED 

OFFICE OF WATER DIRECTION

Region 8 implemented effective procedures to approve and

evaluate Colorado’s water quality standards setting, except

it did not consistently disapprove standards when State

decisions were not sufficiently supported. Region 8 did not

have procedures to oversee and evaluate Colorado’s water

quality testing and assessing, and water quality assessment

reporting. Region 8 oversight efforts focused on the

development of standards while placing little emphasis on

Colorado’s monitoring activities. Region 8 actions mirrored

the Office of Water priorities in the Region’s current water

management agreement. Colorado, in turn, placed more

attention on the development of its standards program than

on monitoring, assessing, and reporting activities. 

WATER MANAGEMENT

AGREEMENT LISTS

PRIORITIES AND

MEASURES

The fiscal 1998-1999 water management agreement

between Office of Water and Region 8 listed the priority

activities for the Region, and contained the measures the

Region uses to report on water program accomplishments

to the Office of Water. Water quality standards

development was listed as one of the top regional priorities. 

The agreement detailed regional actions planned for

assisting states in developing and adopting water quality

standards and included a measure for improving state water

quality standards. The agreement also stated the Region

would continue working with states to develop effective

monitoring programs, and that emphasis on reporting

responsibilities would be a regional priority. However, no

regional actions were detailed, and the agreement did not

include measures to support actions to improve state

monitoring and reporting programs.
Colorado Water Quality Standards,

Monitoring, and Reporting Program

22 Report No. E1HWF8-07-0004-9100093

REGION 8 ACTIVELY

PARTICIPATED IN 

COLORADO’S

STANDARDS

PROGRAM

Region 8 had effective procedures to approve and evaluate

Colorado’s water quality standards and placed a high

priority on the oversight of State water quality standards

development. Region 8 participated in Colorado’s public

review process by testifying at Water Quality Control

Commission hearings, developed multiple guidance

documents, and interpreted complex EPA Office of Water

policy and put it in tangible terms for the State. Regional

approval of Colorado’s water quality standards was often

delayed, however, due to consultations with U.S. Fish and

Wildlife Service on the Endangered Species Act. In

addition, Region 8 did not consistently disapprove

Colorado’s water quality standards where Colorado did not

adequately support ambient-based criteria or did not

provide special studies to support that the swimmable use

was not attainable. Overall, Region 8 was very involved in

Colorado’s standards development process and

development of water quality standards to protect the

State’s waters. 

REGION 8 HAD LIMITED

INVOLVEMENT IN

COLORADO’S

MONITORING

PROGRAM

Region 8 did not have procedures to oversee and evaluate

Colorado’s water quality testing and assessing, and water

quality assessment reporting. Region 8 had not recently

conducted a program review of Colorado’s monitoring

activities nor evaluated Colorado’s monitoring plans. The

negotiated water management agreement between Office of

Water and Region 8 did not contain measures for

monitoring program activities. Consequently, Region 8 did

not consider oversight of Colorado’s monitoring activities a

regional program priority. 

CONCLUSION Although Region 8 was actively involved in the

development of standards to protect the integrity of

Colorado waters, Region 8 was not involved in Colorado’s

testing of its waters. As a result, Region 8 needs to develop

effective procedures to oversee and evaluate Colorado’s 
Colorado Water Quality Standards,

Monitoring, and Reporting Program

23 Report No. E1HWF8-07-0004-9100093

water quality testing and assessing, and water quality

assessment reporting.

RECOMMENDATIONS We recommend the Regional Administrator:

5-1. Clarify Region 8's role and commitment for

providing technical and program support to

Colorado’s monitoring and assessment

programs.

5-2. Identify weaknesses and areas of

improvements for Colorado’s monitoring

and assessment programs and assist in the

implementation of corrective actions.

AGENCY AND STATE

COMMENTS AND OIG

EVALUATION

Region 8 and Colorado agreed with both recommendations. 

Colorado welcomed both contributions from Region 8

technical staff and the opportunity to work with them in

ongoing efforts to enhance the monitoring and assessment

programs. 
Colorado Water Quality Standards,

Monitoring, and Reporting Program

24 Report No. E1HWF8-07-0004-9100093

EXHIBIT 1 

SCOPE AND METHODOLOGY

We reviewed Colorado’s internal controls over water quality standards setting, monitoring, and

reporting. We analyzed internal controls to assure compliance with federal statutory and

regulatory criteria and with Colorado policies and procedures. We determined whether Region

8's Federal Managers’ Financial Integrity Act reports disclosed any material weaknesses related to

the audit. We reviewed the management agreement measures in Region 8's agreement with Office

of Water and the core performance measures in Region 8's agreement with Colorado, to identify

whether they contained the Office of Water Government Performance Results Act goals for water

quality. Our audit disclosed areas needing improvement and areas of commendation for both

Colorado and Region 8, which are discussed in Chapters 2 through 5.

To determine Colorado’s processes for establishing water quality standards, we interviewed

Colorado’s Water Quality Control Division staff and flowcharted their processes for developing

and adopting water quality standards. We reviewed Colorado’s water quality standards as

adopted in its Regulation No. 31. The Basic Standards and Methodologies For Surface Water,

and reviewed policy and guidance papers to determine if established water quality standards were

in compliance with the Clean Water Act and applicable federal regulations. 

To review Colorado’s monitoring program, we interviewed staff of the Water Quality Control

Division and flowcharted their process for monitoring and assessing water quality data. We

reviewed Colorado’s monitoring plans to identify the location and extent of water quality

monitoring. We also flowcharted Colorado’s processes for preparing and reporting on the water

quality assessment report and the impaired waterbody list. We reviewed Colorado reports and

assessed whether Colorado reports for reporting water quality were consistent with federal

regulations and EPA guidance.

We judgmentally selected 57 waterbodies to test and evaluate the processes for setting use

classifications, establishing water criteria, monitoring and assessing waterbodies, recording

monitoring data in EPA’s computerized data system, and reporting on water quality. We chose

the 57 waterbodies for the following reasons: (1) waterbodies with water quality criteria for

bacteria adopted at levels higher than recommended to support the national swimmable use

classification, (2) waterbodies with ambient-based criteria, (3) waterbodies where temporary

deviations were issued and/or expired, (4) waterbodies chosen to verify accuracy and

completeness of the 1996 water quality assessment report and the 1998 impaired waterbodies list,

(5) waterbodies chosen to verify accuracy and State implementation of either the 1996 or 1997

Colorado monitoring plan, or (6) waterbodies without an aquatic life use classification. 

We reviewed National Pollutant Discharge Elimination System permits for major facilities in
Colorado Water Quality Standards,

Monitoring, and Reporting Program

25 Report No. E1HWF8-07-0004-9100093

Colorado. We reviewed the permits to determine if they included permitted discharges of

pollutants for which Colorado did not have water quality standards. 

To determine if Region 8 implemented effective procedures to approve water quality standards

and evaluate Colorado’s water quality standards setting, testing, assessing, and reporting, we

interviewed Region officials to determine how they ensured compliance with the Clean Water Act

and applicable federal regulations and guidance. We identified their processes for reviewing

Colorado’s water quality standards, water quality inventory report, and the impaired waterbodies

list. We reviewed correspondence between Region 8 and Colorado.
Colorado Water Quality Standards,

Monitoring, and Reporting Program

26 Report No. E1HWF8-07-0004-9100093

APPENDIX I

AGENCY RESPONSE
Colorado Water Quality Standards,

Monitoring, and Reporting Program

27 Report No. E1HWF8-07-0004-9100093

ATTACHMENT

Editorial Suggestions (suggested additions in bold)

16. Page 2; second complete paragraph: “... Acute criteria is are designed ..... while chronic

criteria is are designed ....”. Also suggest adding a sentence e.g “ To supplement

numeric criteria, States also adopt narrative criteria (often in the form of ‘free from’

statements) that describe the desired water quality goals (and ideally

implementation procedures for these narrative provisions).” 

P Page 2; fourth complete paragraph: “States are required to hold public hearings for the

purpose of reviewing their water quality standards at least once every 3 years ... “. 

P Page 5; last paragraph: “The Clean Water Act charged EPA with developing water quality

criteria guidance for priority pollutants ........ place the responsibility on states to adopt

water quality criteria (numeric and narrative) to protect water use classifications. where

EPA has not developed criteria.

P Page 11; recommendation 3-1: “... its monitoring program to included advanced testing

....”

P Page 13; first paragraph, second sentence: “ ... prompted Colorado to accurately prepare

the impaired and threatened waterbodies list ...”

P Page 13; first paragraph under BACKGROUND, last sentence: “... control requirements

are not stringent enough to achieve attain or maintain the water quality ...”.

P Page 13; last paragraph: “Colorado appeared to develop a complete and accurate impaired

and threatened waterbody list...”.

P Page 15; first paragraph: “Although a high emphasis was placed on the preparation of the

impaired and threatened waterbody list ...”.

Regional Responses to Recommendations

Recommendation 2-1.

Work with Colorado to adopt the national swimmable use classification and

corresponding criteria limits where attainable, or conduct the required special studies

with consideration of basinwide special studies. Disapprove Colorado water quality
Colorado Water Quality Standards,

Monitoring, and Reporting Program

28 Report No. E1HWF8-07-0004-9100093

standards submissions which do not comply with these options.

EPA Region 8 Response:

The Region agrees that additional work is needed, at both the Regional and State level, to

bring Colorado into compliance with federal requirements addressing water quality standards for

the protection of recreation uses.

Background to Regional Response: 

To date, the Region has addressed this problem by: (1) working with the State before

and during each triennial review to assist the State to adopt standards that meet federal

requirements, and (2) exercising its authority to disapprove revisions that do not satisfy federal

requirements. These efforts are described in more detail below.

Assistance with Triennial Reviews

Colorado’s triennial review process for reviewing and revising segment-specific

designated uses and numeric standards begins with an informational hearing. The purpose of

these hearings is to take public comments on whether the water quality standards should be

continued in their current form or changed in some respect. The practice of EPA Region 8 is to

submit written comments at Colorado’s informational hearings, identifying issues of concern. Our

comments address whether there are segments with water quality standards that do not support

the uses specified in the Clean Water Act (CWA) § 101(a)(2) (the fishable/swimmable goal), and

provide notice of the federal requirement to complete, and make available for public comment,

use attainability analyses for those segments. The Region also notifies the State that any

proposals to remove a designated use specified in CWA § 101(a)(2) or adopt a modified use that

requires less stringent criteria also requires completion of a use attainability analysis.

With respect to water quality standards for recreation, our comments identify the

availability of guidance documents issued by the Region in 1992 and 1994 as a supplement to the

EPA’s national guidance. The 1992 Regional guidance identifies available options and makes

recommendations to assist States and Tribes to comply with federal requirements. Our 1994

guidance provides a recommended worksheet for completing use attainability analyses for

recreation uses.

Disapproval of Submitted Revisions

The Region’s preference is to work with Colorado in a proactive manner, throughout each

triennial review, to assist the State to adopt water quality standards that meet federal

requirements. However, there have been two occasions when the Region disapproved water

quality standards adopted by Colorado that were not protective of recreation uses and were not

supported by a use attainability analysis. In a letter dated September 13, 1991, the Region
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Monitoring, and Reporting Program

29 Report No. E1HWF8-07-0004-9100093

disapproved the water quality standards for more than two hundred segments in four of the

State’s seven basins because the standards were not protective recreation uses, and use

attainability analyses had not been completed. In a letter dated July 16, 1992, the Region

disapproved the water quality standards for more than eighty additional segments located in the

South Platte, Laramie, Republican, and Smoky Hill River Basins, again because the standards

were not protective of recreation uses and use attainability analyses had not been completed. In

the years following these two disapproval actions, the State has upgraded the recreation standards

for many of the disapproved segments and elsewhere. However, there is a need to complete use

attainability analyses for the segments that still do not include recreation uses and standards

consistent with the CWA § 101(a)(2) goal. It is our understanding that the Division has drafted a

recreation use attainability analysis worksheet that it plans to use to complete the required

analyses.

Recommendation 2-2.

[Work with Office of Water to remove the ambiguity in national guidance for adopting drinking water

supply criteria and] Recommend Colorado consistently adopt Clean Water Act criteria designed to protect

human health for all State waters classified for drinking water supply.

EPA Region 8 Response:

 The Region does not agree with this recommendation as presented in the draft report. 

First, the issue of ambiguity in national guidance is not an appropriate issue to be raised in a Statespecific report (and thus it is recommended the language be deleted). Further, EPA Region 8 has

recommended that States and Tribes adopt numeric standards for drinking water segments based

on either CWA human health criteria or Safe Drinking Water Act (SDWA) standards, whichever

are more stringent. The Region believes that Colorado’s numeric standards for drinking water

segments meet or exceed minimum federal requirements. The background explains Colorado’s

approach in more detail and presents the basis for concluding that it is consistent with federal

requirements.

Background to Regional Response

Ambiguity in National Guidance

The Region has (and continues to) discuss this issue with our Headquarters office. This is a

recognized National issue, and as such does not seem appropriate to raise in a State-specific review

effort. Part of the ambiguity is due to statutory construction and different mandates outlined in the

CWA as compared to the SDWA. This issue is being considered on a National level.
Colorado Water Quality Standards,

Monitoring, and Reporting Program

30 Report No. E1HWF8-07-0004-9100093

Evaluation of Colorado’s Approach

 EPA Region 8 has recommended that States and Tribes adopt numeric standards for

drinking water segments based on either CWA human health criteria or SDWA standards,

whichever are more stringent. The Region would not recommend exclusive reliance on CWA

human health criteria because of the importance of ensuring that source waters for public water

supplies achieve a level of water quality that is equal to or better than SDWA Maximum

Contaminant Levels (MCLs). The Region believes that Colorado’s numeric standards for drinking

water segments meet or exceed minimum federal requirements. The recommendation addresses

the fact that, for particular segments and some pollutants, the State has not selected the most

protective of the several acceptable approaches that EPA has established for States and Tribes. 

Colorado’s approach and the basis for concluding that it is consistent with federal requirements are

explained and discussed in more detail below.

Concern has been raised regarding 42 waterbodies where both a drinking water and an

aquatic life class 2 designated use have been adopted. For these segments, the State has not

concluded, to date, that there is a need to assign numeric standards protective of fish consumption

uses, and so the State has assigned human health standards designed to protect only water

consumption uses. For other waterbodies in Colorado with both a drinking water and an aquatic

life designated use (i.e., where the State has concluded a need to protect fish consumption uses), the

State has assigned numeric standards protective of both water and fish consumption. Particularly

for pollutants that exhibit a strong tendency to accumulate in fish tissues, numeric standards that

assume human exposure only through water consumption will be less stringent than those that

assume both water and fish consumption.

States have the option of assigning numeric standards protective of fish consumption uses

to all waters with aquatic life designated uses. Colorado has elected not to follow that more

stringent approach, but rather to assign such standards to aquatic life class 2 segments only where

there is need to provide the extra level of protection (based on the site-specific potential for fish

consumption uses). However, all aquatic life class 1 segments are assigned numeric standards

protective of fish consumption uses on a statewide basis. The Region believes this approach to

protecting fish consumption uses is reasonable and consistent with federal guidance, primarily

because of the large number of low-flow waterbodies in Colorado that do not support catchablesize fish populations.

When assigning numeric standards to protect water supply uses, States have the option of

using CWA § 304(a) criteria, drinking water values promulgated by the Agency under the SDWA

(i.e., Maximum Contaminant Level Goals (MCLGs) or MCLs), or other scientifically defensible

criteria. Colorado has elected to assign numeric standards to water supply segments that are derived

using the same basic methods that EPA uses to calculate drinking water MCLGs and MCLs. For

some pollutants, SDWA values are more stringent than the CWA § 304(a) criteria. For other

pollutants, CWA criteria are more stringent than the SDWA values. One of the reasons for the

differing levels of stringency is that CWA criteria include explicit consideration of exposure through

fish consumption. SDWA standards do not consider fish consumption, although they typically
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31 Report No. E1HWF8-07-0004-9100093

assume that only a fraction (e.g., 20%) of total exposure is through water consumption. Under

EPA’s national water quality standards program guidance, the approach used by Colorado to assign

numeric standards protective of drinking water uses is acceptable. For some (but not all) pollutants,

Colorado’s approach results in numeric standards less stringent than those published by the Agency

pursuant to CWA § 304(a). EPA Region 8 has issued guidance to all of its States and Tribes

recommending, for segments with a drinking water designated use, adoption of either the CWA

criterion or the SDWA MCLs, whichever is more stringent (see Numeric Criteria to Protect Water

Supply Uses, EPA letter to Colleagues signed by Carol Campbell, Director, Ecosystems Protection

Program, January 24, 1996).

The Region has worked with Colorado to further develop the State’s methodology for

identifying aquatic life class 2 segments with the potential to support fish consumption uses. It is

our understanding that the State staff intend to: (1) review all aquatic life class 2 segments that have

not been assigned fish consumption standards (i.e., not just those with a water supply designated

use), (2) propose appropriate revisions to the standards for those segments, and (3) request public

comments on its findings as part of each triennial review. The Region understands that State staff

will confer with Colorado Division of Wildlife field biologists to identify segments where fishing

occurs and segments where fish are stocked by the Division of Wildlife.

Recommendation 2-3.

Continue to encourage Colorado to develop written justification supporting the appropriateness of adopting

ambient-based criteria and disapprove water quality standards submissions that include inadequate analysis.

EPA Region 8 Response:

The Region agrees with the recommendation, additional work is needed, at both the

Regional and State level, to improve the process by which ambient-based numeric standards are

developed and adopted.

Background to Regional Response:

It is particularly important to improve the written justification that is made available for

public comment and included in the record. The Region intends to continue its efforts to work

with the State on this issue and to carefully review ambient-based numeric standards submitted to

EPA for approval/disapproval.

The Region believes that Colorado’s provision authorizing ambient-based numeric

standards is acceptable under current federal requirements. As explained in EPA Region 8

correspondence with the Colorado Water Quality Control Division dated September 5, 1997:
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32 Report No. E1HWF8-07-0004-9100093

EPA approved the State’s ambient-based criteria provision, despite the lack of explicit authority in

40 CFR 131.11, because of our determination that in situations where “human caused conditions”

or “naturally occurring pollutant concentrations” may be a basis for removing the designated use

under 40 CFR 131.10(g), it is more protective and therefore also acceptable to maintain the

designated use and establish ambient-based criteria. It was also our conclusion that, in either of

these two situations, such criteria would protect the aquatic life use that currently exists or is

attainable. In the “human caused conditions” situation, admittedly, such waters may not be able to

support the full range of aquatic species that the natural habitat and water quality would support,

but if the existing water quality conditions truly are irreversible, establishing ambient-based

standards will ensure that existing conditions do not deteriorate further and provide protection for

the aquatic species that constitute the existing and potential aquatic community in the segment.

The Region believes that there is a need to improve the State’s methodology for developing

and adopting ambient-based numeric standards. Our September 5, 1997 correspondence with the

State recommended that the Water Quality Control Division prepare a document that clarifies its

policies and procedures for ambient-based criteria. We specifically suggested that such a document

would need to cover procedural issues, establish methods and policies addressing “natural” and

“irreversible man-induced” sources, identify minimum elements of a rationale supporting ambientbased criteria, and identify situations where other options may be more appropriate than ambientbased standards (e.g., temporary modifications or variances). We intend to continue working with

the State to improve its process for establishing ambient-based numeric standards and to carefully

review ambient-based numeric standards submitted to EPA for approval/disapproval.

Recommendation 3-1.

Provide technical assistance to help Colorado formulate a long range plan to expand its monitoring program

to include advanced testing techniques.

EPA Region 8 Response:

The Region agrees with the recommendation; chemical-specific water quality testing alone

does not provide all the necessary information to determine the biological condition of waters. The

Region also agrees that additional monitoring data (which include biological monitoring as well as

physical habitat indicators, tissue chemistry, sediment chemistry, pathogens, and toxicity testing,

where appropriate) would provide Colorado with a better basis for determining the effectiveness of

its water management program and answer the question: What is the condition of State waters? 

Background to Regional Response:

The fact that Colorado's program focuses on chemical-specific water quality testing is not

surprising. For the past 20 years, EPA's water quality standards and permitting programs have

emphasized a chemical-specific approach to water quality. Colorado's monitoring program, which

supports water quality standards and permitting, has reflected this historic approach. In the past
Colorado Water Quality Standards,

Monitoring, and Reporting Program

33 Report No. E1HWF8-07-0004-9100093

several years, EPA's water quality standards and permitting programs have emphasized more

advanced techniques such as biological criteria. And while there is not yet a long range plan in

place, Colorado has employed several more advanced testing techniques including biomonitoring,

habitat assessments, and toxicity testing. In addition, Colorado, like other interior Western States,

has had to operate its ambient monitoring and assessment program under a chronic shortage of

resources. Only this year has the Section 106 grant funding formula been revised to better reflect

the needs of Western States and their ambient monitoring programs. EPA's monitoring and

assessment regulations, guidance, and policies are not specific regarding what constitutes an

adequate monitoring and assessment program and do not provide clear priorities for directing

limited resources.

There are several activities in the Region that will serve to provide technical assistance to

Colorado in long-range planning to expand its monitoring program. First, the Region is developing

a 5-year plan for developing Regional and State capabilities in biological monitoring and assessment. 

Colorado's technical assistance needs will be part of this plan. Limited financial resources are

available from EPA Headquarters to meet some of these needs through contracts for technical

assistance. This Regional 5-year plan can serve as a basis for Colorado's long-range plan. One

example of technical assistance that will be part of this 5-year plan will be technical support to

Colorado for a database for biological data that also includes some data analysis capabilities. Such a

database is currently being developed under an EPA contract with Headquarters, and will soon be

available to State programs. The Region plans to work with Colorado to incorporate their existing

data into this database, and to provide training on database use for future information management

needs. Clarification of additional needs for technical assistance in the area of biological monitoring

and assessment will take place during State visits as well as during a Regional biological monitoring

and assessment workshop to be scheduled in the next few months. 

A second Regional activity that will provide technical assistance to Colorado for long-range

planning is the Region's involvement in EPA's Environmental Monitoring and Assessment

Program (EMAP) Western Pilot. The EMAP Western Pilot will be carried out in partnership with

EPA's Office of Research and Development, the States, and other monitoring agencies. One

objective of this project is the development of needed environmental indicators appropriate for

characterizing the ecological condition of water resources. We will be meeting with Colorado and

other Western States to discuss their involvement in this project and identify assessment questions. 

Within Colorado, biological, chemical, and habitat data will be collected and analyzed. A long range

strategic plan is currently being prepared by the Region's EMAP Western Pilot Coordinator, which

will address the involvement of Colorado's monitoring and assessment program, including the

critical element of technology transfer. 

The Region will continue to work with Colorado, through the Continuing Planning Process

and the Performance Partnership Agreement (PPA), to incorporate activities and measures as

appropriate, to support long-range planning for water quality monitoring, assessment, and

reporting. 
Colorado Water Quality Standards,

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34 Report No. E1HWF8-07-0004-9100093

Recommendation 3-2.

Request that Colorado develop and implement a process to obtain and use other sources of organic pollutant

monitoring or monitor for organic pollutants themselves.

EPA Region 8 Response:

The Region agrees with the recommendation. 

Background to Regional Response:

 The Region is concerned that Colorado does not have a process to obtain data for organic

pollutants, such as pesticides and herbicides, for use in water quality assessments. The Region will

request that Colorado develop and implement a process to obtain and use such data, as part of their

own monitoring program or from other state divisions and federal agencies. Given that other state

divisions and federal agencies do monitor and test for organic pollutants, the Region believes more

progress can be made by developing a structured process for obtaining organic pollutant data from

these sources. This agrees with EPA's long-term 305(b) goal of increasing input from monitoring

sources outside of the core State program. 

The Region notes that Colorado's Water Quality Control Division is currently forming a

Colorado Water Quality Monitoring Committee, which is made up of representatives of various

entities (i.e., local, state, and federal agencies, academia, industry, and non-profits) that conduct

water quality monitoring in Colorado. This Committee should serve as a good forum for

improving coordination and data-sharing. The Region has a representative on this committee, and

we will request and encourage data sharing and the development of structured processes for filling

data gaps in Colorado's monitoring program. In addition, data-sharing should be improved by the

use of EPA's modernized STOrage and RETrieval (STORET) water quality database by agencies

and groups in addition to Colorado's Water Quality Control Division. The modernized STORET is

more user-friendly and better captures the types of data and information which allow for datasharing, and their use and technical support is strongly supported by the Region. 

To ensure that there is adequate coverage for monitoring and assessment in Colorado, the

Region will ask for monitoring work plans and monitoring strategies. The development of work

plans and strategies should serve to identify which parameters will be measured by Colorado's

monitoring program and where. They will also allow for pro-active coordination with other

monitoring agencies or groups for obtaining additional parameters as well as water quality data from

locations not monitored. In addition, the work plan and strategy should include a section on

coordination, where Colorado can identify other agencies or groups with data and information that

can support Colorado's ambient monitoring and assessment program, and describe the processes

that will be used for data sharing.
Colorado Water Quality Standards,

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35 Report No. E1HWF8-07-0004-9100093

Recommendations 4-1 and 4-2.

Persuade Colorado to follow the national guidance in preparing the water quality assessment report and

include complete, accurate information.

Work with Colorado to develop a database to maintain water quality assessment data. 

EPA Region 8 Response:

The Region agrees with both recommendations.

Background to Regional Response:

The Region agrees that Colorado did not follow the recommendations in the national

guidance, specifically the preparation of tables of the percent of assessed waters (river miles and lake

acres) fully, partially, or not supporting each individual use classification. We note that States are

not required but encouraged to follow national guidance. In this particular instance, though, EPA

has strongly encouraged and supported the States in presenting their assessment information in the

formats described in the national guidance and presented in the appendices of the National Water

Quality Inventory Report to Congress for several reasons. First is to ensure consistency in

reporting of 305(b) assessment data such that State data can be aggregated into a national summary

for use by the Congress, the public, and others. Second, the 305(b) data presented in these tables

are also the Core Performance Measures that EPA will use for reporting progress under the

Government Performance Results Act. Colorado has committed to reporting this information as

part of the PPA. 

 

Colorado's 1996 305(b) report presented assessment data tables such as (1) State summary

data on overall use support and (2) miles and lake acres meeting, not meeting, and not attainable for

fishable and swimmable criteria. One target audience for Colorado's 305(b) report is the State's

Water Quality Control Commission, and this presentation of data met their needs for information. 

These tables do not translate into the tables requested by EPA, which identify the percent of

assessed miles and lake acres fully, partially, or not supporting each individual use classification. 

One solution to this incompatibility of data is the development and use of a database for water

quality assessment data, which can sort and present the data into the specific formats requested by

various audiences. An assessment database will enable Colorado to meet the information needs of

both the State and EPA, as well as other users of assessment information such as local

governments, citizens and watershed organizations. 

EPA's old assessment database, the WaterBody System, was not user-friendly and was not

adopted by all States nor supported technically by the Region. Colorado did not use the

WaterBody system and did not develop or use an alternative assessment database. Instead,

Colorado carried out assessments using data downloads from STORET, EPA's water quality

database. EPA Headquarters, through a contractor, is currently developing a new Assessment

Database, which will address many of the shortcomings of the WaterBody System. Colorado has

undertaken the first steps towards using this database by working with EPA's contractor to identify
Colorado Water Quality Standards,

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36 Report No. E1HWF8-07-0004-9100093

waterbody segments that will serve as the spatial framework for this database. This work has been

completed, and next steps are to incorporate the data from State assessments into the database

once a final version is distributed by EPA. The Region plans to provide technical support for this

database, and work with Colorado to ensure its use. Colorado should be able to report assessment

information in EPA's requested format for the year 2000 305(b) report. Thus, the Region agrees

with and is committed to the recommendation to work with Colorado to develop a database to

maintain water quality assessment data. 

The report indicates that “Colorado made presumed assessments by classifying waterbodies

as fully supporting in the absence of organic pollutant monitoring data.” The Region agrees with

the national guidance that “presumed assessments” (e.g. determining that a waterbody is in full

support in the absence of sufficient information to make an assessment) are not appropriate. The

Region will work with Colorado to prevent such presumed assessments from being used. However,

the Region does support State assessment determinations of “evaluated waters”, consistent with the

national guidance. Evaluated waters are those waterbodies for which the use support decision is

based on information other than current site-specific ambient data, such as data on land use,

location of sources, predictive modeling, and questionnaire surveys of fish and game biologists. 

The Region supports State discretion in making determinations of impairment, particularly in

situations where obvious problems occur, in order to more efficiently utilize limited ambient

monitoring resources. We also recognize that Colorado cannot directly monitor for all possible

types of data in order to conduct use support determinations. 

Recommendations 5-1 and 5-2.

Clarify Region 8's role and commitment for providing technical and program support to Colorado's

monitoring and assessment programs.

 Identify weaknesses and areas of improvements for Colorado's monitoring and assessment programs and

assist in the implementation of corrective actions.

EPA Region 8 Response:

The Region agrees with both recommendations.

Background to Regional Response:

The Region has recently expanded the monitoring and assessment program staff in several

areas including several new full-time and part-time positions to provide support to the Region's

monitoring and assessment program activities, one new student intern position, and part-time

support from several program areas including biologists at the Region's laboratory. There are plans

to add two temporary full-time positions to provide technical assistance for Regional monitoring

projects. In addition, the Region has hired a new full-time water quality database administrator. 

These recent increases in staff provide added capacity to devote to issues and needs identified with

Colorado's monitoring and assessment programs.
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37 Report No. E1HWF8-07-0004-9100093

The Region has provided technical and program support to Colorado's monitoring and

assessment programs in the past, and will continue to do so in the future. Relatively recent

technical support efforts included Regional workshops supporting biomonitoring and

bioassessment, and Regional participation in Colorado's Sediment Task Force which developed

implementation guidance for determining impacts to aquatic life by the deposition of sediment. 

Past program support included review of monitoring work plans when provided, workshops

supporting the 305(b) process, review of 305(b) reports, and contract support for spacial display of

waterbody segments. 

Present and planned technical and program support activities include support to Colorado

for several EPA water quality and assessment databases (including the modernized water quality

database STORET, an assessment database, and a database for biological data). We will continue to

provide technical support to Colorado on biological monitoring/bioassessment. Our Region's and

Colorado's involvement in the EMAP Western Pilot and our completion of the Regional-EMAP

project in Colorado headwater streams will allow for technical transfer opportunities regarding

monitoring designs and improved environmental indicators. Our Region's and Colorado's

involvement with the National Fish Tissue Study as part of the Clean Water Action Plan will reduce

the uncertainty associated with current fish tissue monitoring activities, and eventually provide

Colorado with comprehensive information on the severity and extent of fish tissue contamination

in the state. The Region will continue to support the formation of a Colorado Water Quality

Monitoring Committee through active participation, which we view as very important towards

improving data-sharing and coordination among the multiple monitoring agencies and groups in

Colorado. In addition, the Region provides financial and technical support for monitoring

activities in Colorado as part of the nonpoint source program, TMDL program, and several other

water quality management programs. 

Concerns and areas of improvement for Colorado's monitoring and assessment programs

will be identified as part of a state visit/program review, to be conducted in Colorado during FY99. 

In addition, we will continue to participate in the Continuing Planning Process, the PPA process,

and other planning activities.
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38 Report No. E1HWF8-07-0004-9100093

APPENDIX II

STATE RESPONSE

February 2, 1999

Bennie S. Salem

Divisional Inspector General

U.S. Environmental Protection Agency

Office of the Inspector General

Central Audit Division

726 Minnesota Avenue

Kansas City, KS 66101

Re: Audit Report E1HWF8-07-004-XXXX

Dear Ms. Salem:

Enclosed are Colorado’s comments on the draft report of the Colorado’s Water Quality Standards,

Monitoring, and Reporting Audit. We appreciate your recognition of Colorado’s achievements. We

are proud of these efforts and are continually striving to improve our program. We would also like

to recognize the good working relationship with Region 8 EPA, that has evolved over the years.

Their support and technical advice in the areas of monitoring, standards and assessments have been

invaluable.

We appreciate the opportunities you have afforded us to review several of the issues that were

identified at the preliminary stages of the audit process. This dialogue has resulted in many important

clarifications and improvements in the evaluation. However, in review of the report we found the

following two facts regarding our program to be inaccurate or potentially misleading to the reader:

1. On page 6, regarding adoption of “swimmable” uses where evidence that the use is in place

for a specific stream segment. There still appears to be confusion between class 1 and class

2 recreation. Although the term “non-motorized travel” is evidence of recreation, it is not

evidence of class 1 recreational use (please see the regulations). Rather, this term has been

used to refer to hiking or wading through a stream. Kayaking and tubing are recognized as

class 1 uses (see 31.13(1)(a)); however, there is no documented use in the specific segment

in question (North Fork of the Gunnison River, segment 3). Examination of OIG’s

supporting documentation bears out that Colorado has correctly assigned recreational use

classifications, according to our regulations. Moreover, we believe that Colorado’s EPAapproved definition of which recreational uses should be class 1 (based on the likelihood of

ingesting water) continues to be appropriate.
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40 Report No. E1HWF8-07-0004-9100093
Colorado Water Quality Standards,

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Revised 2/8/99 41 Report No. E1HWF8-07-0004-9100093

Colorado Department of Public Health & Environment

Water Quality Control Division’s

Comments Regarding

Colorado’s Water Quality Standards, Monitoring and Reporting Audit

EXECUTIVE SUMMARY

We recommend the Regional Administrator

# Work with Colorado to improve its support for water quality standards decisions

and disapprove future water quality standards submissions which lack adequate

analysis and support.

Colorado Response:

We welcome EPA Region 8's continued involvement in our standards-setting process and

appreciate the Region’s willingness to work with us on the front-end of the process, rather than

just at the approval/disapproval stage. The high level of technical and scientific involvement

offered by the Region over the past 20 years has helped make Colorado’s programs very

successful.

# Assist Colorado in increasing the comprehensiveness of its state water quality

monitoring program.

Colorado Response:

Colorado welcomes EPA Region 8's continuing involvement in the development of annual and

long-range monitoring plans. We rely on their participation as we broaden our scope and

continue to work with a full range of stakeholders to enhance our water quality monitoring

efforts.

# Urge Colorado to follow national guidance in preparing the water quality

assessment report.

Colorado Response:
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Revised 2/8/99 42 Report No. E1HWF8-07-0004-9100093

Colorado is committed to an ongoing process of improving the usefulness of our water quality

assessment reports and increasing their consistency with national goals. Colorado is working

closely with Region 8 to provide the information necessary to assist EPA in preparing the national

water quality assessment report.

# Develop procedures to oversee and evaluate Colorado’s water quality testing,

assessing, and water quality assessment reporting.

Colorado Response:

Colorado welcomes EPA’s assistance in our ongoing efforts to continually enhance our water

quality testing, assessing, and water quality assessment reporting. We have invited Region 8 to be

a partner in the Colorado’s newly formed “Colorado Monitoring Council” which is intended to

improve not only the Water Quality Control Division’s testing, assessing and reporting

procedures, but also that of our many federal, state, local and private partners.

CHAPTER 2

We recommend the Regional Administrator:

2-1 Work with Colorado to adopt the national swimmable use classification and

corresponding criteria limits where attainable, or conduct the required special

studies with consideration of basinwide special studies. Disapprove Colorado

water quality standard submissions which do not comply with these options.

Colorado Response:

Colorado acknowledges that more documentation is desirable to support decisions regarding

adoption of recreational use classifications. Colorado has recently implemented a procedure to

address this concern at the time of the basin triennial review and subsequent rulemaking hearings. 

This will include providing the Water Quality Control Commission (and EPA) with completed

Recreational Use Attainability Analysis forms that will be a structured assessment of the factors

affecting the attainment of the “swimmable” use. 
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However, we believe that the OIG auditors have mis-characterized Colorado’s adherence to

regulatory policy by asserting that Colorado has not adopted swimmable use classifications where

there is evidence that the use is in place. Colorado has two different recreational use

classifications: recreation class 1 and recreation class 2. Recreation class 1 is the classification

that meets EPA’s criteria as “swimmable”. Colorado has explicit regulatory definitions of what

activities are considered class 1 and class 2 recreational activities, based on the likelihood of

ingestion of small quantities of water. Wading, fishing and camping are not considered evidence

of class 1 recreation (i.e. activities in or on the water when the ingestion of small quantities of

water is likely to occur). For the “swimmable” use protection to be applied, evidence of

“recreation” is not enough; it must be evidence of class 1 recreation. Region 8 EPA has been

aware of Colorado’s distinction between class 1 and class 2 recreation since its adoption in its

current form in 1991. The agency has never questioned or contested this regulatory distinction. 

OIG has substituted its own concept of what “ought to be” swimmable, instead of relying upon

Colorado’s established and approved regulatory definition. 

Upon examination of the supporting evidence provided by OIG, the 16 instances of purportedly

inappropriate classification are were actually correctly classified. Class 1 recreational activities

are not documented in those segments. Kayaking and tubing were not documented in the

segment in question, and “non-motorized travel” and “occasional wading” are not evidence of

class 1 or “swimmable” uses in Colorado.

2-2 Recommend Colorado consistently adopt Clean Water Act criteria designed to

protect human health for all waters classified for drinking water supply.

Colorado Response:

Colorado believes that OIG has mis-characterized Colorado’s implementation of human health

protection standards. Colorado has adopted human health standards for all pollutants for which

EPA has developed Clean Water Act criteria. EPA has established criteria based upon exposure

through two pathways: first, ingesting contaminated fish flesh; and second, ingesting
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contaminated fish flesh plus drinking the water in which these fish reside. In addition to these two

human health protection approaches, Colorado has established standards a third way. Where

there is only a water supply use, we have adopted criteria from the Safe Drinking Water Act. 

Colorado has not adopted more restrictive EPA criteria that provide an additional level of

protection to protect against the combined risks of drinking water and fish ingestion unless there

was reason to believe that significant fishing occurs for the waters in question. Colorado has

consistently applied this approach. Furthermore, EPA Region 8 has determined that this approach

is protective of human health and is consistent with federal requirements.

2-3 Continue to encourage Colorado to develop written justification supporting the

appropriateness of adopting ambient-based criteria and disapprove water

quality standards submissions that include inadequate analysis.

Colorado Response: 

Colorado acknowledges that more documentation is desirable to support decisions regarding

adoption of ambient standards, particularly in triennial reviews subsequent to their initial adoption. 

Colorado has recently implemented procedures to ensure that the triennial review records are

more instructive regarding the history of the segments in question. The Division will identify

when the existing standards were adopted and recap the basis for the decisions in the Rationale

document. An analysis of whether there is a basis for maintaining ambient standards in light of

existing conditions will also be provided.

CHAPTER 3

We recommend the Regional Administrator:

3-1 Provide technical assistance to help Colorado formulate a long range plan to

expand its monitoring program to include advanced testing techniques.

Colorado Response:

Colorado is committed to improving its monitoring program and sees the refinement of our

monitoring program as an ongoing, evolutionary process. We welcome any technical assistance
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Revised 2/8/99 45 Report No. E1HWF8-07-0004-9100093

that EPA Region 8 can provide us towards this end. At the state level, we have already taken a

significant step towards improvement by convening a Statewide Monitoring Council in November

1998. Participants on this council include representatives from government (including EPA),

academia, the regulated community and citizens groups involved in water quality monitoring in

Colorado.

With regard to the OIG’s portrayal of Colorado’s monitoring program as lacking in advanced

techniques, we are uncertain what the OIG means by the term “advanced”. Colorado interprets

this to mean that the state does not have the most desirable balance, in OIG’s opinion, of

different types of monitoring activities. Indeed, Colorado’s program has placed the greatest

emphasis on water chemistry, due to both the strong numeric water quality standards program

that has been developed in Colorado, and the recent national emphasis on identifying impaired

water bodies and developing total maximum daily loads (TMDLs). This is not to say that the

state has completely neglected other types of monitoring. As stated by the OIG, we do conduct

biological and physical monitoring including macroinvertebrate surveys, fish population surveys,

and habitat surveys. We are currently expanding our capabilities to increase these types of

monitoring and assessments within the constraints of multiple competing priorities for time and

resources.

Region 8 EPA has provided Colorado with substantial assistance and guidance in biological and

habitat monitoring through various means. Regional staff members have conducted

bioassessment workshops and individuals have participated on Colorado’s advisory committees

for developing biological monitoring methods and for developing methods to assess clean

sediment impacts to aquatic life. Colorado welcomes the continuation of this type of

involvement in the future. We have asked for assistance in the installation and implementation of 

a STORET-compatible database for biological and physical habitat data, and we will be working

with Region 8 in developing a comprehensive long-term monitoring strategy.
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3-2 Request that Colorado develop and implement a process to obtain and use other

sources of organic pollutant monitoring or monitor for organic pollutants

themselves. 

Colorado Response:

Colorado’s surface water monitoring program presently does not include monitoring of organics

such as pesticides and herbicides because (1) it has been our observation that organic chemicals

attributable to agricultural activities have rarely been found in harmful concentrations in Colorado

surface waters, and (2) due to the very high costs of monitoring these compounds, we have relied

on data collected by other programs or other agencies while focusing our available resources on

higher monitoring priorities. For example, over the past three years approximately 300

groundwater wells, many located in major agricultural areas of the state, have been tested for

nutrients, pesticides and herbicides by the Division’s groundwater program. We consider data

collected by the U.S. Geological Survey in our assessments. The U.S. Geological Survey has

monitored agricultural chemicals in their National Water-Quality Assessment Program

investigations in the Rio Grande, South Platte River, and the Upper Colorado River basins. 

Drinking water systems in Colorado sample their source water for a broad suite of organic

chemicals, including pesticides and herbicides.

Colorado welcomes ideas for a better means to incorporate organic chemical monitoring data into

our assessments and will explore, with Region 8 EPA, the need and opportunities for organic

chemical monitoring by the state in our efforts to develop a long-term monitoring strategy. 

CHAPTER 4

We recommend the Regional Administrator:

4-1 Persuade Colorado to follow national guidance in preparing the water quality

assessment report and include complete, accurate information.

Colorado Response:

Colorado shares EPA’s national concern that currently, because of inconsistent reporting of water
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quality among states, EPA has difficulty aggregating this state data to provide comparisons and

analysis on a national scale. EPA must grapple with the results of contradictory themes in the

Clean Water Act: flexibility and consistency. On the one hand, the CWA directs the States and

Tribes to develop standards systems and water quality management programs that fit their

individual needs. This leads inevitably to different and unique systems in every state. On the

other hand, EPA is directed to ensure a base level of protection for the nation’s waters and to

report on the condition of the nation’s waters to Congress. This is tremendously difficult if there

are more than 50 different systems to reconcile.

Colorado acknowledges that we do not currently follow the entire body of national guidance in

preparing the water quality assessment report, although we do meet all regulatory reporting

requirements. OIG might acknowledge that “guidance” is advisory, not binding. Colorado is

committed to making ongoing progress towards a complete, accurate and comprehensive water

quality assessment report. Colorado’s 1998 305(b) Report is evidence of that commitment and

that progress. Within the constraints of available resources, Colorado is also committed to

increasing the consistency of its assessment reports with federal guidance.

4-2 Work with Colorado to develop a database to maintain water quality assessment

data.

Colorado Response:

Although EPA does not require a water quality assessment database, Colorado agrees that a

database to maintain water quality assessment information would improve our ability to report the

types of information that EPA desires. Colorado maintains extensive documentation of all water

quality assessment decisions in the Statements of Basis and Purpose. To have these assessments

summarized in a database could make them more accessible and easier to report. We look

forward to receiving the newly revised Water Body System database from EPA Headquarters

when it becomes available (possibly as early as February 1999). Colorado and Region 8's

resources should not be spent duplicating Headquarters activities, especially in view of EPA’s 
Colorado Water Quality Standards,

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Revised 2/8/99 48 Report No. E1HWF8-07-0004-9100093

concern about national consistency (see 4-1 above).

CHAPTER 5

We recommend the Regional Administrator:

5-1 Clarify Region 8's role and commitment for providing technical and program

support to Colorado’s monitoring and assessment programs.

Colorado Response:

Colorado continues to welcome the contributions from Region 8 technical staff to our standards,

monitoring and assessment programs. The individuals on EPA’s staff have continuously assisted

us with issues as varied as technical expert testimony on complex standards issues, to 

participating on multi-month work groups on developing clean sediment assessment guidance. 

Their time and assistance has been much appreciated and we look forward to continuing this

valuable interaction in the future.

5-2 Identify weaknesses and areas of improvement for Colorado’s monitoring and

assessment programs and assist in the implementation of corrective actions.

Colorado Response:

Colorado welcomes the opportunity to work with Region 8 staff in our ongoing efforts to

continually enhance our monitoring and assessment programs.
Colorado Water Quality Standards,

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49 Report No. E1HWF8-07-0004-9100093

APPENDIX III

ABBREVIATIONS

CFR Code of Federal Regulations

DIMP Diisopropymethylphosphonate

EPA Environmental Protection Agency

OIG Office of Inspector General
Colorado Water Quality Standards,

Monitoring, and Reporting Program

50 Report No. E1HWF8-07-0004-9100093

APPENDIX IV

DISTRIBUTION

Office of Inspector General

Inspector General (2410)

Deputy Assistant Inspector General for Internal Audits (2421)

Headquarters Audit Liaison (2421)

Divisional Inspectors General for Audit

EPA Headquarters Office

Assistant Administrator for Water (4101)

Agency Followup Official (2710)

Agency Followup Coordinator (3304)

Associate Administrator for Regional Operations and State/Local Relations (1501)

Associate Administrator for Congressional and Legislative Affairs (1301)

Associate Administrator for Communications, Education, and Public Affairs (1701)

EPA Region 8

Assistant Regional Administrator, Ecosystems Protection & Remediation

Director, Ecosystems Protection Program

Audit Followup Coordinator 

Regional Offices

Regional Administrators

Colorado Department of Public Health and Environment

Director

Division Director, Water Quality Control Division