United States
Environmental Protection
Agency
Office Of Water
(WH-550)
EPA 570/9-91-037
September 1991
v>EPA
Ground Water Indicator
Pilot Study
In The State Of Idaho
Printed an Recycled Paper
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GROUND-WATER INDICATOR PILOT STUDY
IN THE STATE OF IDAHO
Office of Water
U.S. Environmental Protection Agency
September 1991
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EXECUTIVE SUMMARY
The U.S. Environmental Protection Agency (EPA), Office of Ground Water and Drinking Water
(OGWDW) is investigating the use of indicators to track progress and trends in ground-water quality
protection efforts. This report presents the results of a pilot study in the State of Idaho to identify the
availability and usefulness of existing ground-water data to support the use of these indicators. Five
ground-water quality indicators were investigated in this pilot study:
Maximum Contaminant Level (MCL) exceedances in ground-water
based public drinking water supplies;
On-site and Off-site contamination at hazardous waste sites;
Volatile organic compound (VOC) concentrations in ground water;
Nitrate concentration in ground water; and
Pesticide use.
EPA conducted this pilot study to determine whether the criteria for reporting ground-water indicators,
as developed by a 1986 EPA workgroup, could be met with data collected for the State of Idaho.
These criteria include the following:1
indicators should be based on actual data measurement;
indicators should lend themselves to graphic display to convey trends
and other information readily;
whenever possible, existing data should be used rather than requiring
new data collection;
data should be collected over time at the same locations; and
data can have limitations and still be useful as an 'indicat.br' of ground-
water problems or progress.
In general, this study found that data characterizing four of the five indicators are available and that
these data lend themselves to graphic display, as depicted in this report. Due to the lack of pesticide
data collected by Idaho, no data on this indicator were available for presentation or discussion in this
pilot study.
EPA used only existing data for this analysis, although EPA noted the need for additional data
collection to better characterize several of the indicators. EPA also found that much of the ground-
water monitoring data compiled for this study did not fully support trend analyses because samples
were not taken from the same locations over time. Nonetheless, EPA concluded that if the limitations
are understood, data are available in Idaho to at least partially characterize four of the five ground-
water indicators.
Indicator Data Management in Idaho
One or more sources of data were identified to characterize the indicators. After reviewing these
sources, principal data sources were identified for each indicator, as follows:
1 US. EPA, Office of Ground-Water Protection, April 1989. "Indicators for Measuring Progress in Ground-Water
Protection." EPA 44016-99-006
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IV
MCt and drinking water data were compiled from the U.S. EPA
Federal-Reporting Data System;
Waste site data were gathered primarily from paper records
maintained by the Idaho Hazardous Materials Bureau and U.S. EPA
Region X;
VOC data were drawn from the U.S. Geological Survey (USGS), Boise
District data base called QWDATA; and
Nitrate data were retrieved from the USGS QWDATA data base, the
U.S. Forest Service (USFS) regional campground water quality data
base, and the Idaho Water Quality Bureau (WQB) Rathdrum Prairie
data base.
Analysis of the Data
The data drawn from the above sources are summarized in this report in graphical format. The raw
data are also presented in tables in appendices to this report. Analysis of these data was
complicated by differences in data format and organization among the data bases. In addition, some
of the agencies maintaining data bases that participated in this pilot study did not have sufficient
resources to support the study fully. Therefore, the pilot study focused on the use of readily available
data, although additional relevant data sources are noted in this report.
Achievement of the National Objectives for the Indicators
In an April 1989 report, EPA identified specific national objectives for each indicator examined in this
pilot study. The following discussion presents specific conclusions relating to the achievement of the
national objectives for each of the indicators.
Maximum Contaminant Levels: Data from the FRDS-II data base are sufficient to support the national
objectives for this indicator. However, Idaho personnel report uncertainties in the quality of the
available data. Although EPA limited the analysis presented in this study to county-level summaries of
MCL violation information, the analysis could be organized at different geographic levels and could
include analyses of the populations potentially at risk from the violations. The population data
maintained in FRDS, however, may not accurately reflect size of the population exposed to a particular
MCL violation.
On-Site and Off-Site Contamination at Hazardous Waste Sites: Sufficient data are available in
RCRA and CERCLA site files to characterize the level of contamination, the status of off-site
contaminant migration, and the populations at risk for specific areas. However, Idaho has not
recorded the data in a State-wide automated data management system. Therefore, EPA had to
manipulate the data manually to present it in a format useful for 305(b) reports. Due to the relatively
labor intensive effort required to manually manipulate the data, EPA analyzed the data from only a few
hazardous waste sites. Therefore, the on-site and off-site hazardous waste site data collected for this
report represent only a 'snapshot' of the extent of contamination at the waste sites.
Volatile Organic Compounds: EPA accessed data maintained in the USGS QWDATA base to
characterize the VOC indicator. Although USGS was able to provide data for only a few select
counties, EPA was able to organize this data at the county level and display trends in VOC levels
graphically. However, because VOC data in the QWDATA bases were limited to only a small number
of well characterized sites, EPA determined that the limited geographic distribution of the VOC
analyses limited the usefulness of the data to support a State analysis. A more thorough and
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consistent VOC sampling and analysis program could be developed to better support analyses of
trends in VOC levels State-wide.
Nitrates: EPA accessed data maintained in the USGS QWDATA data base, the USFS Intermountain
Region data base, and the WQB Rathdrum Prairie data base. Multiple data bases were utilized to
characterize the nitrate indicator since, individually the three data bases did not have sufficient
geographic coverage. EPA was able to organize the data at the county level and display trends in
nitrate levels graphically. Because the data were collected and maintained by different agencies,
however, the validity of comparisons should be reviewed. Nonetheless, EPA has concluded that
sufficient data are available to at least partially address the national objectives.
Pesticide Use: No data are available in Idaho to characterize this indicator. Therefore, EPA could not
collect data to access the extent of contamination from this indicator of ground-water quality. The
State may wish to begin collecting information on use of pesticides for indicator reporting.
Existing Practices
In completing this pilot study, EPA encountered a number of problems relating to the quality and
availability of the compiled data which limit their application to support the indicator objectives. The
problems concerning the quality of the data related both to the representativeness or geographic
coverage of the data and to the procedures used to collect the analytical results. In particular, EPA
identified the following technical issues:
there is an insufficient volume of data for some indicators;
data are limited in geographic coverage;
sampling is not consistent in geographic coverage;
sampling is not consistent over time;
securing and analyzing samples was not uniform;
limited repeat sampling is conducted at the same location; and
sampling depths vary.
In addition to these technical issues, EPA also identified problems with regard to the way in which the
collected data were managed. These data management issues limited EPA's ability to access and
use the information provided by the State:
missing annual data or other gaps were not explicitly identified;
data bases were originally organized to support objectives that differ
from those the indicators were designed to address; and
different agencies were responsible for data presented, leading to
potential inconsistencies.
Suggested Revisions to Existing Practices to Support Indicator Reporting
EPA is strongly promoting the wider use of indicator data collection across all Federal and State
programs. An EPA Task Force, with State participation, developed concrete principles and objectives
to ensure effective and consistent decision-making in all Agency decisions affecting ground water, and
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will also institute State Comprehensive Ground-Water Protection Programs.2 Monitoring and data
collection is one area that will be addressed.
As Idaho continues its monitoring and data collection efforts and begins to develop its comprehensive
program, it is important to keep the issues noted in the pilot study in mind. For example, sampling
and analytical consistency may be promoted by establishing consistent scientific and data collection
protocols and by promoting the development of ground-water monitoring networks, as appropriate, to
provide trend data. Data management activities that employ standard data collection formats for each
of the indicators are already underway in Idaho to maintain standard data management protocols
between agencies. Cooperative efforts between EPA and Idaho will ensure that information collection
activities support the objective of protecting the nation's ground-water resources.
To begin moving toward data consistency, EPA, with States and other Federal agency work group
participants developed a set of the most critical data elements for ground-water quality information.
These data elements form the foundation upon which ground-water data users may build their own
data base, adding elements to meet their specific needs. The use of this minimum set of data
elements (MSDE) will ensure that EPA and the State can share and manipulate ground-water data to
support better environmental decision-making, and facilitate cross-program integration.
Once adopted, these revisions will support the collection, management, and reporting of indicator data
necessary for future 305(b) reports.
Resources For Implementing
Initially, the resources required at the State level to implement national indicator reporting may be
extensive. Idaho cannot significantly improve its data collection and reporting without expending the
necessary resources to correct deficiencies. As the State establishes monitoring networks and
integrates their information systems, data will become more accessible for use in indicator
development. Furthermore, after the information is collected and the data elements and data
reporting formats for including ground-water indicators in 305(b) reports are identified and applied, the
effort expended for completing the 305(b) report will be greatly reduced.
Next Steps
This pilot study is one of three studies EPA completed investigating the use of ground-water indicators
in 305(b) reports. A Findings Report has been prepared which outlines and summarizes the
information and knowledge gathered in Idaho, Minnesota, and New Jersey. The Findings Report also
makes recommendations regarding the implementation of indicators in future 305(b) reports. Based
on these recommendations, EPA is developing a Technical Assistance Document (TAD)4 to provide
technical guidance to the States on how to gather and use indicator data as part of their 1992 305(b)
Reports. The TAD is also intended to help set the stage for those States that are moving toward
developing comprehensive ground-water monitoring and information systems, particularly in
relationship to ground-water indicator reporting, and to assist those which are already in the process.
The TAD is expected to be completed by early 1992.
2 U.S. EPA, Office of the Administrator, "Protecting the Nation's Ground Water: EPA's Strategy for the 1990s,"
EPA 21Z-1020, (Washington, D.C.) July 1991.
3 U.S. EPA, Office of Ground Water and Drinking Water, "Definitions for the Minimum Set of Data Elements for
Ground-Water Quality," (Washington, D.C.) July 1991 (draft final).
4 U.S. EPA. Office of Ground Water and Drinking Water, "Technical Assistance Document," (Washington, D.C.)
September 1991 (draft).
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Table of Contents
Page
EXECUTIVE SUMMARY jjj
I. INTRODUCTION 1
A. Overview and Purpose of the Report 1
B. Description of the General Research Approach 3
C. Outline of the Report 5
II. SUMMARY OF IDAHO HYDROGEOLOGY AND GROUND-WATER USE 7
A. Hydrogeologic Setting 7
B. Populations Relying on Ground-Water 8
III. GROUND-WATER INDICATORS 9
A. Maximum Contaminant Levels 9
B. On-Site and Off-Site Contamination from Hazardous Waste Sites 14
C. Volatile Organic Compounds 19
D. Nitrates .' 24
E. Extent of Agricultural Pesticide Use 34
F. Additional Indicators Identified by Idaho Personnel 35
IV. STUDY CONCLUSIONS 37
A. Existing Practices 38
B. Suggested Revisions to Existing Practices to Support Indicator Reporting . . 39
C. Resources for Implementing 39
D. Next Steps 39
BIBLIOGRAPHY 41
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IX
Appendices
Page
Appendix A: Summary Data for MCL violations for Selected Counties in Idaho A-1
Appendix B: Summary Data of Hazardous Waste Site Contamination Concentration Levels B-1
Appendix C: Supplementary Publications on Nitrate and VOC Data C-1
Appendix D: Summary of Volatile Organic Compound Detections for Butte and Jefferson
Counties, Idaho D-1
Appendix E: Summary of Nitrate Detections for Selected Counties in Idaho E-1
Appendix F: Summary of Agencies that Track Indicator Data in Idaho F-1
Appendix G: Environmental Indicator Questionnaire G-1
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XI
List of Tables
Table A-1: Number of MCL Violations for Nitrate for Selected Counties in Idaho . .
Table A-2: Number of MCL Violations for Total Coliforms for Selected Counties in
Idaho
Table A-3: Number of MCL Violations for Gross Alpha Particle Activity for Selected
Page
A-2
A-3
Table A-4-
Table B-1:
Table D-1
Table D-2:
Table E-1:
Table E-2:
Counties in Idaho
Number of MCL Violations for Fluoride for Selected Counties in Idaho
Summary of Hazardous Waste Site Contamination Concentration Levels for
Selected Counties in Idaho
Summary of VOC Detections for Butte County, Idaho
Summary of VOC Detections for Jefferson County, Idaho
Nitrate Detections for Selected Counties in Idaho, U.S. Geological Survey . . .
Nitrate Detections for Selected Counties in Idaho, U.S. Forest Service
M980-1984)
A-4
A-5
B-2
D-2
D-3
E-2
E-3
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XIII
List of Exhibits
Page
Exhibit 1: County Map of Idaho 4
Exhibit A-1: MCL Violations for Total Coliforms for Selected Counties in Idaho 12
Exhibit B-1: Summary of Hazardous Waste Site Contamination Concentration Levels 17
Exhibit C-1: VOC Detections for Selected Counties in Idaho 22
Exhibit C-2: VOC Detections for Butte County, Idaho 23
Exhibit D-1: Nitrate Detections for Selected Counties in Idaho, USGS 28
Exhibit D-2.1: Nitrate Detections for Selected Counties in Idaho, U.S. Forest Service 29
Exhibit D-2.2: Nitrate Detections for Selected Counties in Idaho, U.S. Forest Service 30
Exhibit D-2.3: Nitrate Detections for Selected Counties in Idaho, U.S. Forest Service 31
Exhibit D-3: Nitrate Detections for Kootenai County, Idaho Water Quality Bureau 32
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I. INTRODUCTION
A. OVERVIEW AND PURPOSE OF THE REPORT
The U.S. Environmental Protection Agency (EPA), Office of Ground Water and Drinking Water
(OGWDW) is responsible for ground-water policy coordination and planning for the Agency. OGWDW
is also responsible for working with the States to develop and implement State ground-water policies
and guidelines, enhance ground-water data management, and initiate and conduct special studies of
ground-water contamination.1
As part of this overall ground-water effort, U.S.EPA has been investigating the use of indicators used
to track progress and trends in ground-water protection efforts. In April 1989, EPA published the
Report, Indicators for Measuring Progress in Ground-Water Protection, which presented the results of
a three phase process used to develop a set of ground-water indicators. The process stressed a
number of principles that should be considered when choosing and verifying potential indicators,
including:
indicators should be based on actual data measurement;
indicators should lend themselves to graphic display to convey trends
and other information readily;
whenever possible, existing data should be used rather than requiring
new data collection;
ideally data should be collected over time at the same locations; and
data can have limitations and still be useful as an "indicator" of ground-
water problems or progress.
The indicators, which are described below, can be used by States as part of their biennial National
Water Quality Inventory Report to Congress under the Clean Water Act, Section 305(b).
EPA selected three states (New Jersey, Minnesota and Idaho) as part of a pilot study to investigate
the usefulness of these indicators to track progress in ground-water protection efforts. This report
presents the results of the investigation in the State of Idaho to identify the availability and usefulness
of existing ground-water data. EPA selected Idaho to represent Western and less densely populated
States.
EPA collected the data presented in this report with the assistance of the State of Idaho, U.S.
Geological Survey, U.S. Forest Service, and EPA Regional and Headquarters personnel. While EPA
discusses a number of data bases in this report, only selected data are presented due to problems in
data acquisition and resource limitations.
1 U.S. EPA, Office of Ground-Water Protection, April 1989, "Indicators for Measuring Progress in Ground-Water
Protection," EPA 44016-88-006
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Rationale for Ground-Water Indicators
EPA developed a set of indicators that EPA and the States can use to track progress and set priorities
in ground-water protection efforts.2 The initial set of ground-water indicators includes:
Maximum Contaminant Levels (MCLs) - This indicator measures quality
of ground-water used for public drinking water supplies, the
effectiveness of ground-water protection efforts, and the population at
risk from contaminated supplies.
On-Site and Off-Site Contamination from Hazardous Waste Sites - This
indicator tracks contamination in and around hazardous waste sites as a
measure of the effectiveness of ground-water protection programs, the
potential risk to drinking water supplies, and the population served by those
supplies.
Volatile Organic Compounds (VOCs) - This indicator measures ground-water
contamination from industrial and non-industrial activity.
Nitrate - This indicator measures area-wide ground-water contamination from
sources such as agricultural activity and septic systems.
Extent of Agricultural Pesticide Use - This indicator measures pesticide usage
in agricultural areas.
These indicators encompass existing data and data that can be collected by the State over time. The
indicators also lend themselves to graphic display to convey trends in ground-water quality and
vulnerability.
Reporting Indicators Under the 305(b) Process
An important application for the indicator data will be in developing State Water Quality Reports for
inclusion in the biennial National Water Quality Inventory Report to Congress under Section 305(b) of
the Clean Water Act. Section 305(b) mandates that States develop and report information concerning
the quality of the nation's water resources to EPA and the U.S. Congress. The 305(b) process is an
essential aspect of the national water pollution control effort. It is the principal means by which EPA,
Congress, and the public evaluate water quality, the progress made in maintaining and restoring water
quality, and the extent to which water quality problems remain. Many States rely on the 305(b)
process to gather the information needed to conduct program planning and to report to their
legislatures on progress in ground-water pollution control and resource protection programs.
The Idaho 1988 Water Quality Status Report and Nonpoint Assessment (305(b) Report) was prepared
by the Idaho Department of Health and Welfare. Division of Environmental Quality (DEQ), Water
Quality Bureau (WQB). The ground-water section of the report presents an assessment of the current
status of the State's ground-water quality, its associated programs, and nonpoint sources of ground-
water contamination. The report details ground-water quality and quantity conditions in the State
and the current management efforts for the resource. The conclusions addressing ground-water
quality include:
2 U.S. EPA, February, 1989, "Guidelines for the Preparation of the 1990 State Water Quality Assessment (305(b)
Report)", page 23.
3 Idaho Department of Health and Welfare, Division of Environmental Quality, Water Quality bureau, 1988. "Idaho
Water Quality Status Report and Nonpoint Assessment."
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Ground-water quality in the State is generally good with some
localized contamination.
The most common point sources of contamination are above and
below ground petroleum storage, leaks and accidental spills of
industrial chemicals, and land application of wastewater.
Nonpomt sources are poorly understood principally because
monitoring data are inadequate or nonexistent.
Data on nitrate-nitrogen are the most widely available information on
ground-water quality.
Virtually no monitoring has been conducted for agricultural chemicals
in ground water.
It is expected that the use of indicators will assist Idaho in further characterizing trends in the quality
of it's ground water as part of future 305(b) reports.
B. DESCRIPTION OF GENERAL RESEARCH APPROACH FOR THE STUDY
EPA developed research strategies to demonstrate the manner in which ground-water indicator data
are and can be collected and reported in the State of Idaho. The activities included on-site interviews,
follow up contacts, preparation of a project plan, collection and analysis of data, and final report
preparation.
EPA worked with a principal State contact to identify key personnel responsible for ground-water
quality indicator data bases. The principal contact scheduled on-site interviews with these key
personnel on January 29 and 30, 1990, to discuss the project, review supporting documentation,
identify available information, discuss data formats, determine data management requirements, identify
other key personnel and data bases, and request assistance in preparing the specified information.
EPA and contractor staff scheduled follow-up interviews to review data availability and usefulness, and
to discuss specific features of the data bases. EPA and contractor staff developed a written Project
Plan to present the results of the interviews and follow-up contacts, and to identify specific
characteristics for each of the indicator data bases.
Following distribution of the Project Plan, personnel responsible for key data bases were contacted by
EPA and contractor staff to review any specific questions, respond to data requests, and set time
frames to collect the data. State and Federal Agency personnel provided indicator data on tape and
computer disk. This report presents the results of the analysis of those data, and discusses the
methodologies used and the concerns identified during the data compilation efforts.
EPA collected indicator data State-wide by county, where available, for four of the five indicator
parameters. An identifiable set of data on the statewide or regional use of pesticides does not exist in
Idaho. Therefore, EPA did not collect data for this indicator. For most indicators, data were presented
for those counties that had received the most comprehensive ground-water monitoring and therefore
have the best available ground-water quality information. Exhibit 1 presents a county map of Idaho
and highlights those counties from which the majority of the ground-water data used in this study
were collected.
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EXHIBIT 1
COUNTY MAP OF IDAHO
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C. OUTLINE OF THE REPORT
Following the introduction to the indicator concept for measuring the progress of ground-water
protection efforts presented in Section I, Section II of this report presents a summary of the
hydrogeologic setting in Idaho and characterizes ground-water use and the populations that rely on
this resource. Section III presents detailed information on each of the ground-water indicators
analyzed in Idaho. Each indicator discussion presents information on the national objective of the
indicator, a description of the indicator, a description of the data available in Idaho to characterize the
indicator, the approach used to collect and analyze those data, the results and interpretation of the
data, suggested revisions to the data collection process, and a conclusion regarding the availability of
sufficient data to address the national objectives. Section IV presents the study conclusions, including
a summary of the findings for each indicator, a discussion of the technical and data management
factors limiting the availability of data to support the study, suggestions for modifications to data
management practices, and, finally, a brief discussion on resources needed and the next steps EPA is
planning to take to implement ground-water indicator reporting.
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II. SUMMARY OF IDAHO HYDROGEOLOGY AND GROUND-WATER USE
A. HYDROGEOLOGIC SETTING
The major aquifers in Idaho are categorized under two rock types, sedimentary and volcanic, and are
grouped into six hydrologic basins, known as the Panhandle, Clearwater, Salmon, Southwest Idaho,
Upper Snake River, and Bear River basins.4 The basins are based on hydrologic units developed by
the U.S. Geological Survey (USGS) and contain systems with similar geology and hydrology. Five of
the basins drain to the Columbia River, and the sixth (the Bear River basin) drains to the Great Salt
Lake.
Panhandle Basin
The Panhandle basin is the northernmost of the six basins and contains five major aquifers:
Quaternary Alluvium and Colluvium, Quaternary Glacial Deposits, Tertiary Columbia River Basalt
Group, Tertiary and Cretaceous Granitic Rocks, and Cambrian and Precambrian Sedimentary,
Igneous, and Metamorphic Rocks. These aquifers are primarily unconsolidated sedimentary aquifers
in intermountain valleys, comprised of glacial outwash with recent alluvium.5
Clearwater Basin
The Clearwater basin occupies the southern portion of the Idaho Panhandle, and is divided into the
Columbia River Basalt Group and regions of thermal springs. The Columbia River Basalt Group
contains four aquifers: the Palouse River aquifer, the Moscow basin aquifer, the Clearwater Uplands
aquifer, and the Clearwater Plateau aquifer. The Palouse River and Moscow Basin aquifers are in the
northwest corner of the basin, and are overlain by alluvium. The Clearwater Upland and Clearwater
Plateau aquifers cover the western half of the basin, are separated by the Clearwater River, and are
recharged from different drainage basins. Thermal water (found in springs near Warm Springs Creek
and Elk City) discharge sodium bicarbonate water from the granitic Idaho basolith.
Salmon Basin
The Salmon Basin, surrounding the Salmon river directly south of the Clearwater basin, contains three
major aquifers and two categories of springs. The three aquifers are the Lemhi, Pahsimeroi, and
Round Valley aquifers. All three aquifers are composed of unconsolidated valley-fill deposits. The two
types of springs are thermal water springs (with temperatures above 20 degrees Celsius) that contain
water from the Idaho basolith, and cold water springs (with temperatures below 20 degrees Celsius).
Southwest Idaho Basin
The five major geologic units of the Southwest Idaho basin (occupying the southwest corner of Idaho)
are located near the Snake river. These aquifers are the Idaho Group of Tertiary and Quaternary age,
Younger Holocene Terrace Gravel, Older Pleistocene Terrace Gravel, Glenns Ferry Formation, and the
Bruneau Formation. These sedimentary and volcanic aquifers are shallow and unconsolidated, and
are composed of gravel, sand, silt, and clay with interbeddings of basalt, shale, and sandstone.
4 Johnson J.S. Yee and William R. Souza, 1987, "Quality of Ground Water in Idaho", U.S. Geological Survey
Water-Supply Paper 2272.
5 Idaho Department ol
"Idaho Water Quality Status Report and Nonpoint Source Assessment, 1988"
5 Idaho Department of Health and Welfare, Division of Environmental Quality, Water Quality Bureau, 1988,
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Upper Snake River Basin
The Upper Snake River basin is the largest of the six basins, occupying most of the eastern portion of
Idaho. The Snake River Plain aquifer extends for about 200 miles (from Bliss to Ashton) and
discharges into the Snake river. This aquifer is composed of basalt in the Quaternary age Snake
River Group, with thin interflow beds of Quaternary sediments. The sources of ground-water recharge
are deep percolation from excess irrigation water, seepage from streams, underflow from tributary
basins, and precipitation. The Snake River Plain aquifer is the highest yielding aquifer in Idaho.
Bear River Basin
The Bear River basin is the smallest of the six basins, occupying the southeast corner of Idaho. The
three major aquifers of the Bear River basin are the Curlew, Cache, and Bear River valleys. All three
aquifers are composed of stream-deposited, unconsolidated materials and volcanic rocks (valley-fill
and alluvial aquifers).
B. POPULATIONS RELYING ON GROUND WATER
Approximately 6,400 million gallons per day (mgd) of ground water were withdrawn from Idaho
aquifers in 1980. Ground water is the source of over 90 percent of Idaho's drinking water (194 mgd),
and serves a population of approximately 827,000. Over 64 percent of the ground water withdrawn is
used for irrigation (4,100 mgd), while 33 percent (2,100 mgd) is used for industry, and 2 percent is
used for drinking water.6
6 U.S. Geological Survey, 1985. "National Water Summary 1984," Water Supply Paper 2275
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III. GROUND-WATER INDICATORS
This section discusses the data availability and findings related to the five indicators investigated in
the State of Idaho.
A. MAXIMUM CONTAMINANT LEVELS
This section presents the national objectives, approach and findings of the study of maximum
contaminant levels (MCLs) as an indicator of ground-water quality in public drinking water supplies in
Idaho.
National Objectives
EPA designed the MCL indicator to address the following national objectives:7
identify the degree to which ground-water based water supply systems meet
all applicable MCLs;
identify the size of the population at risk from systems in violation;
provide an understanding of the geographic distribution of populations
potentially at risk;
identify specific contaminants for which systems are failing to meet the MCLs;
and
identify those contaminants that are responsible for the greatest number of
MCL violations.
The following discussion describes the data sources identified in Idaho to .address these objectives,
and presents and analyzes the data results.
Description of the Indicator
MCLs are water quality standards set under the authority of the Safe Drinking Water Act (SDWA). The
Act authorized EPA to establish a cooperative program among local, State and Federal agencies to
protect drinking water quality and to ensure that human health is not adversely affected by water-
borne pollutants. MCLs are set for inorganic, organic, microbiological contaminants, radionuclides,
and turbidity.8
An MCL is the highest amount of a specific contaminant allowed in the drinking water supplied by a
public water system. Primary MCLs are established for contaminants that are known to occur in
drinking water, cause adverse health effects, and can be measured with existing instrumentation.
7 U.S. EPA, Office of Ground-Water Protection, April 1989, "Indicators for measuring Progress in Ground-Water
Protection," EPA 44016-88-006.
8 Data characterizing turbidity violations are not described in this report because this parameter is generally not
considered relevant to analyses of ground-water based supplies.
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10
Indicator Data Management in Idaho
Idaho manages MCL data in two principal data bases. The first is the public water supply data base
maintained by the Idaho Division of Environmental Quality (DEQ), Water Quality Bureau (WQB). The
second data base is the Federal Reporting Data System (FRDS-II) maintained by EPA's Office of
Drinking Water.
Idaho's WQB compiles and manages MCL compliance data on approximately 3200 public drinking
water systems (PWSs) across the State. The WQB maintains these data in a central PWS data base,
which is currently being transferred from an Apple Macintosh to an IBM-based computer system. Of
the 3200 PWSs in Idaho, approximately 2300 to 2400 are ground-water based, non-community
systems that are administered by the Idaho Public Health Districts. The Public Health Districts and
WQB have yet to establish a routine, formalized process for reporting the MCL data for these ground-
water systems to the data base. Five of the seven Idaho Health Districts have reported some of their
data to the WQB, although many of the data records may be incomplete.
The WQB MCL data base tracks a number of data elements including a PWS identification number,
the address including the county where the PWS is located, and the population served. The data
base managers have also entered latitude and longitude information for approximately 80 percent of
the towns that have PWSs. These latitude and longitude data, however, do not locate the wellheads
themselves. In addition, the data base also tracks analytical contaminant concentration levels for all
constituents that are assigned Federal MCLs. Idaho maintains these data from 1978 to the present.
Data prior to 1978 are available for only those systems that have exhibited recurrent MCL violations.
The WQB regularly reports MCL data to FRDS-II, which serves as the national data base for tracking
MCL compliance data provided by the States. EPA's Office of Drinking Water maintains the FRDS
data base to support the Agency's information collection requirements established under the SDWA.
The FRDS data base tracks a number of data elements including the PWS identification number, the
location of the PWS, the population served, the sources of drinking water (ground and/or surface
water), the MCL constituent violated, the concentration reported, the federally mandated maximum
allowable concentration level for each MCL constituent, the date of the violation, and the number of
months the system was in violation.
The data from FRDS, however, contains the following deficiencies:
FRDS data reflect the analysis of finished drinking water and therefore
do not represent ground-water quality at the well;
the locations of PWSs are provided in longitude and latitude of either
the drinking water source (as provided by the owner) or the centroid of
the zip code of the system mailing address. Either of these data may
be erroneous, as the operator may provide inaccurate information, or
the mailing address of the water system may be miles away from the
well source;
systems that are served solely by ground water are designated as
ground-water based systems, but those systems that are served by
both ground and surface water are designated as surface-water
based systems, regardless of the degree to which the system relies on
ground water;
population data provided by FRDS are total populations served by a
PWS. As a PWS may use several sources to serve this population, it
may be difficult to estimate the size of the population exposed to MCL
violations;
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11
FRDS provides no information on the location of actual exposure
points, the proportion of a reported population served by each source.
or the period during which each source is used;
data on the location of private wells and the population using private
wells for drinking water are not collected in FRDS; and
FRDS personnel support capabilities are likely to be overburdened with requests if
States cannot access data themselves.
Approach for Characterizing the Indicator
EPA's review of the data sources described above revealed that data retrievals from the FRDS-II data
base would provide the best available information to track trends in MCL violations in Idaho. The
WQB was unable to provide analyses and summary data of it's data base due to budget constraints.
Furthermore, EPA believed that the data available through FRDS-II were consistent with those
maintained on the WQB data base. Therefore, FRDS served as the sole data source for characterizing
the MCL indicator.
EPA obtained data retrievals from the FRDS-II data base for public water supplies relying solely on
ground water in ten counties: Ada, Bannock, Bonneville, Butte, Canyon, Cassia. Jefferson. Kootenai,
Minidoka, and Twin Falls. These ten counties were chosen to coincide with the seven counties in
which USGS nitrate data were available (see Section III.D, below) plus three additional counties with
relatively high populations.
The data retrievals consisted of public water system violations of Federal MCLs for the years 1980
through March of 1990 for the following constituents:9
Fluoride,
Nitrate,
Total Coliform, and,
Gross Alpha Particle Activity.
Study Results and Interpretation of Data
Well over 95 percent of all MCL violations involved total coliforms. Exhibit A-1 graphically presents the
number of MCL violations by county and by year for total coliforms. Kootenai County, where the
Rathdrum Prairie sole source aquifer is located, had the greatest number of total coliform violations
(50) in 1983 and has also experienced the greatest number of violations overall. Greater than 30
violations were recorded in Bannock County for the years 1982 through 1984, in Kootenai County for
the years 1982, 1983, 1988, 1989, and in Bonneville county in 1989. The number of total coliform
violations were comparatively low in Butte, Jefferson, and Minidoka counties for the entire period of
record.
Differences among the counties, in terms of the number of total coliform MCL violations from 1982
through 1989, may be explained by differences in the number of PWSs in the county, the volume of
drinking water supplied by the PWSs, or the quality of the ground-water resource, among other
factors. While this study did not collect sufficient data to analyze and differentiate among these
causes, there does appear to be a downward trend in total coliform violations within two of the
9 No MCL violations were recorded in FRDS for the other MCL constituents; therefore, they are not included in
this summary.
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EXHIBIT A-1
MCL VIOLATIONS FOR TOTAL COLIFORMS
FOR SELECTED COUNTIES IN IDAHO
NUMBER OF VIOLATIONS
60
50
40
30
20
10
0
1
Jliwfl
rv>
ADA BONNEVILLE CANYON JEFFERSON MINIDOKA
BANNOCK BUTTE CASSIA KOOTENAI TWIN FALLS
COUNTIES
1982
1983
1984
1985 [H 1986 Qi] 1987
1988
1989
MCL: 1/100 ml
Source: Federal Reporting Data System (FRDS-II)
U.S. Environmental Protection Agency
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13
counties. Cassia and Twin Falls. However, there are no apparent trends in total coliform violations
within the remaining counties for the entire period. Maximum Contaminant Level summary data from
FRDS-II for the ten counties are presented in Tables A-1 through A-4 in Appendix A.
Although the number of total coliform violations in these counties appears to be very high, WQB staff
responsible for forwarding MCL data to FRDS note that only 20 to 30 percent of the reported violations
involve exceedances of the drinking water standard; the remainder involve recordkeeping and
reporting violations.
In addition to the MCL violation data collected from FRDS, information concerning the populations
served by systems in violation are also available. Although these population data are not presented in
this report, they may be compiled by the State for future analyses.
A few conclusions can be drawn regarding the applicability of the data for future 305(b) reports:
MCL and PWS population served data are available at the county
level;
MCL data lend themselves to visual interpretation; and
MCL data allow for analysis of trends both within and among counties.
However, the following problems inherent in the State's MCL data management program limit the
ability to identify significant trends in the indicator data:
a routine, formalized process for reporting MCL data has not been
established;
many of the data records may be incomplete;
total coliform data contain a high percentage of record keeping violations;
periodic backlogs in data entry resulted in incomplete geographic
coverage of data; and
WQB deleted data collected prior to 1978 due to concerns regarding
the accuracy of the analytical results.
Another uncertainty inherent in the data from FRDS-II and the WQB data bases is that they reflect the
analysis of finished drinking water rather than raw ground water, and, therefore, do not necessarily
represent the quality of ground water at the wellhead. This uncertainty is generic to the indicator
itself.
Revisions to the Indicator Data Collection Process
In order to collect data to meet the national objective of this indicator and effectively track trends in
the 305(b) reporting environment, the following revisions to the MCL data collection process are
recommended:
ensure that data are collected in a consistent manner at the regional
level prior to compilation in State data bases;
ensure that the State regularly collects and automates the regional data; and
maintain consistency in sampling and analysis procedures.
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14
Conclusions
Maximum contaminant level data are available in Idaho to graphically track the annual number of
violations in each county by constituent and by year. However, the data records for some of the
counties in the State are incomplete and the quality of historic data records for certain constituents is
questionable. Nonetheless, sufficient data are currently available to identify MCL violations, and the
principal constituents involved. EPA limited the analysis of supply system geographic distribution to
aggregate data organized at the county level, and did not analyze populations potentially at risk.
However, data on geographic distributions and populations served by PWSs are available from FRDS
and are believed to be sufficient to provide a general understanding of the geographic distribution of
the populations at risk. Therefore, this study found that sufficient MCL data are available to meet the
national objectives.
B. ON-SITE AND OFF-SITE CONTAMINATION FROM HAZARDOUS WASTE SITES
This section presents the national objectives, approach, and findings of the study of on-site and off-
site contamination from hazardous waste sites as an indicator of ground-water contamination from
such sources in Idaho.
National Objective
EPA designed the indicator of on- and off-site contamination from hazardous waste sites to support
the following national objectives:10
identify the number of Comprehensive Environmental Response,
Compensation and Liability Act (CERCLA) and Resource Conservation
and Recovery Act (RCRA) sites with ground-water contamination on-
site and off-site;
provide an indication of the risk posed by such contamination to the
population in the vicinity of off-site contamination; and
identify the relative frequency with which various types of contaminants
are responsible for ground-water contamination at CERCLA and RCRA
sites.
The following discussion describes the data sources identified in Idaho to address these objectives
and presents and analyses the data results.
Description of the Indicator
Active and abandoned hazardous waste sites can serve as significant sources of ground-water
contamination and may pose serious risk to human health and the environment. The level of ground-
water contamination at these hazardous waste sites, the potential risk to drinking water supplies, and
the risk to the populations served by those supplies are each assessed individually under this
indicator. This indicator also tracks changes in the number of CERCLA and RCRA sites with on-site
and off-site ground-water contamination over time as a measure of the progress in managing waste
sites. Such indicator data could also be used to monitor progress made in dealing with contaminated
sites by evaluating changes in site identification, remedial investigations, remedial design
implementations, and site closures.
10 U.S. EPA. Office of Ground-Water Protection, April 1989, "Indicators for Measuring Progress in Ground-Water
Protection," EPA 44016-88-006.
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Indicator Data Management in Idaho
Data on ground-water contamination from hazardous waste sites in Idaho are maintained by two
separate agencies. Idaho DEQ, Hazardous Materials Branch (HMB) compiles data on RCRA Subtitle
C facilities and EPA Region X complies data on CERCLA sites in Idaho. Throughout this discussion
the current lead regulatory authority for each site is identified.
Idaho's DEQ, HMB tracks ground-water quality data for seven active RCRA Subtitle C facilities in
Idaho. These seven sites are as follows:
Morrison-Knudsen;
Pressure Treated Timber;
Dart Industries;
Utah Power and Light;
Mountain Home Air Force Base;
Envirosafe Services of Idaho Inc. -- Site A; and
Envirosafe Services of Idaho Inc. - Site B.
Data for all these sites, except the Envirosafe Services Site A, are available in hard copy format only.
Ground-water monitoring data for the Envirosafe Services Site A are automated and are contained in
five ground-water analytical data Lotus 1 -2-3 spreadsheets used to maintain data on the following
parameters:
Volatile Organic Compounds;
Semivolatile Organic Compounds;
Inorganic Compounds, Constituents, and Parameters;
Pesticides and PCBs; and
Physical Measurements and Parameters.
Each spreadsheet contains fields for a primary station code, well identifier, the agency requesting
data, the sample date, depth to water, water level elevation, a number of chemical constituents or
parameters particular to each spreadsheet, and a laboratory data qualifier. One other spreadsheet on
Water Level Measurements, currently not used by the Hazardous Materials Bureau, also contains fields
for survey coordinates reported in either the State Plane Coordinate system, the Universal Transverse
Mercator grid system, or Latitude and Longitude (to the nearest tenth of a second). In addition, a
dBase III file which contains physical parameters for sites to be tracked electronically is available.
HMB's automated Envirosafe Services Site A data are limited to six to ten sampling events conducted
between March 1986 and October 1989. These samples were taken from five distinct wells. Hard
copy data for the remaining six RCRA Subtitle C facilities contain analytical monitoring results for the
same array of chemical and physical parameters contained in the spreadsheets. HMB has collected
these data since approximately 1986. The hard copy files contain a variety of geographic locators for
the monitoring wells, including latitude and longitude, township, range, and section numbers, or site-
specific well identification numbers. In the future, HMB plans to have the analytical monitoring data of
all of the State's RCRA Subtitle C facilities automated and maintained on the same set of Lotus 1-2-3
spreadsheets.
Site data for the six CERCLA sites in Idaho are maintained by EPA Region X. These six sites are as
follows:
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16
Pacific Hide and Fur;
Union Pacific;
Idaho National Engineering Laboratory (INEL);
Kerr McGee;
ARRCOMM (Drexler Enterprises); and
Bunker Hill.
The EPA Region X Ground-Water Office reported selected ground-water data for the six Idaho
CERCLA sites in hard copy format. The selected ground-water quality data include the site name,
county location, contaminant concentration level categories (e.g., unknown, below detection limit,
above detection limit) for a number of classes of contaminants (e.g., PCBs, Pesticides, Synthetic
Organics, Metals), and population affected via drinking water wells. These CERCLA site data are
available for 1989 for all six CERCLA sites, and for 1988 for four of the six sites. Region X does not
include geographic locators among their selected ground-water quality data and identifies the sites by
the facility name.
Approach for Characterizing the Indicator
To meet the objectives of this indicator, EPA requested that officials from both HMB and EPA Region X
complete a Ground-Water Environmental Indicator Questionnaire (developed and used by EPA Region
X) to characterize the on-site and off-site contamination of ground water at hazardous waste facilities
in the State. This questionnaire is provided as Appendix G to this report. EPA requested information
from both of these agencies in order to present data for both RCRA Subtitle C and CERCLA facilities.
The Hazardous Materials Branch maintains the data for the majority of the RCRA Subtitle C facilities in
hard copy files only, and needed to undergo a very time intensive sort of its files to provide the
necessary information. Due to HMB's resource constraints, questionnaires were requested for only
two facilities - the Envirosafe Services Site A facility, for which the necessary data is automated, and
for one additional RCRA Subtitle C facility. The Hazardous Materials Branch complied and provided
the requested information for 1990 for the Envirosafe Services Site A located in Owyhee County, and
the Morrison-Knudsen facility located in Ada County.
Region X officials completed questionnaires for 1989 for all six CERCLA sites in the State and for 1988
for four of the six sites.
The following information from the questionnaires completed by HMB and Region X was used to
characterize this indicator:
site name;
county;
concentration levels (e.g., at/below detection limit) for specific
contaminant categories (e.g., PCBs, Pesticides);
if contamination is reaching drinking water wells; and
population within three miles of site.
Study Results and Interpretation of Data
The INEL (CERCLA) site in Butte County in 1989 is the only site that had concentration levels
exceeding MCLs or other action levels for two contaminant categories (i.e., synthetic organics and
metals). The concentration levels for the other contaminant categories at the INEL site were either at
or below detection limits, or were not analyzed. Exhibit B-1 graphically represents on-site and off-site
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EXHIBIT B-1
SUMMARY OF HAZARDOUS WASTE SITE
CONTAMINATION CONCENTRATION LEVELS
WASTE SITES
MORRISON-1990
PACIFIC HIDE--1988
PACIFIC HIDE--1989
UNION PACIFIC--! 988
UNION PACIFIC--1989
INEL--1989
KERRMCGEE--1989
ARRCOMM--1988
ARRCOMM--1989
ENVIROSAFE--1990
BUNKER HILL--1988
BUNKER HILL--1989
0
UNKNOWN
1
AT/BELOW
DETECTION LIMIT
I
2
ABOVE
DETECTION LIMIT
ABOVE MCL
RGBs
PESTICIDES
SYNTHETIC ORGANICS
METALS
BACTERIA
Source: U.S. EPA Region X and
Idaho Hazardous Materials Bureau
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18
contamination concentration levels for the RCRA and CERCLA facilities. The actual data on
concentration level categories for each contaminant category are presented by site name. Due to the
limited number of sites with available information, the data are not aggregated by county. On-site and
Off-site contamination data at the eight hazardous waste facilities are presented in Appendix B.
The Morrison-Knudsen (RCRA) site in 1990 and the Union Pacific (CERCLA) site in 1988 and 1989
were reported to have synthetic organic or metal concentrations in the site ground water at levels
either above detection limits or above MCLs or other action levels. Data from Region X show that
releases from the INEL (CERCLA) site and the Bunker Hill (CERCLA) site in Shoshone County have
reached drinking water wells. Data summarizing drinking water well contamination associated with the
sites is summarized in Appendix B.
A number of conclusions can be drawn regarding the applicability of the waste site data for future
305(b) reports:
data can be characterized at the county level;
data lend themselves to visual representation; and
as more data are collected over time, data would allow for
comparisons among and within the counties.
However, the small number of waste sites in Idaho limits the utility of reporting waste site data at the
county level. The ability to track trends in the waste site conditions is also limited by the following
factors:
sampling at all sites is not consistent over time;
most sampling at the sites is on a one-time basis; and
different agencies are responsible for managing the data, which may
lead to inconsistencies in data reporting.
Furthermore, data for only a minority of RCRA Subtitle C sites were available for the study. Therefore,
a complete interpretation of the extent of contamination from RCRA sites across the State was not
developed.
The HMB does not summarize the RCRA Subtitle C data in a format that is consistent with the
questionnaire used to characterize this indicator. Furthermore, although EPA Region X does maintain
its CERCLA data in a format consistent with the questionnaire, it has not automated its data base.
Therefore, data from both agencies must be manipulated manually to present it in a format useful for
future 3Q5(b) reports.
Revisions to the Indicator Data Collection Process
In order to collect data to meet the national objective and effectively track trends in the 305(b)
reporting environment, EPA developed the following recommendations to the on-site and off-site
hazardous waste site data collection process based on the experience gained in this pilot study.
maintain consistency in sampling and sample analyses;
sample on a periodic basis, at least annually, and
automate the data collection and maintenance process.
Conclusions
The Idaho on-site and off-site hazardous waste site data collected for this report represent only a
"snapshot" of the extent of contamination at the waste sites. Sufficient data are available to
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19
characterize the level of contamination, the status of off-site contaminant migration, and the
populations at risk for specific areas. Maintaining a trend analysis of these characteristics will require
that paper records are updated over time. However, if data were automated more efficient data
retrievals and trend analyses could be completed.
C. VOLATILE ORGANIC COMPOUNDS
This section presents the national objective, approach, and findings of the study of volatile organic
compounds (VOCs) as an indicator of ground-water contamination in Idaho.
National Objective
EPA designed the VOC indicator to address the following national objective:11
identify the frequency with which VOCs are found in ground water.
The following discussion describes the data sources identified in Idaho to address the objective, and
presents and analyses the data results.
Description of the Indicator
VOCs typically include solvents and other chlorinated hydrocarbons. They serve as indicators of
ground-water contamination resulting from industrial and non-industrial activities. These activities or
sources can include landfills, septic systems, spills, hazardous waste sites, leaking underground
storage tanks, underground injection control wells, industrial sites generally, and other potential point
sources. VOCs also serve as surrogates for other compounds that may be released from these
sources. VOCs can reach the ground water from improper material handling, and leakage of tanks
and industrial equipment at the ground surface.
There is an interest in the level and frequency of VOC contamination due to the possible health
hazards posed by VOCs, and other contaminants from similar sources. As a result, measuring
changes in VOC concentrations over time may provide a valuable indicator of future trends in drinking
water quality resulting from industrial and non-industrial activities.
Indicator Data Management in Idaho
State and Federal agencies in Idaho collected and maintained VOC data in five data bases:
USGS District QWDATA data base;
Idaho WQB UST remedial response records;
Idaho WQB UST site characterization data base;
Idaho WQB Rathdrum Prairie data base; and
U.S. Forest Service (USFS) campground water quality data base.
The USGS District office in Boise has collected ground-water quality data including VOCs from
localized studies conducted in the State. These data are maintained in the QWDATA data base on a
USGS District prime computer in Boise. Data from QWDATA are uploaded from the District prime
computer to the National Water Information System (NWIS) on USGS's main computer approximately
11 U S EPA, Office of Ground-Water Protection, April 1989, "Indicators for Measuring Progress in Ground-Water
Protection," EPA 44016-88-006.
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20
once a month.12 The QWDATA data base tracks a number of data elements including a well
identification number, latitude and longitude, a local identifier (township, range, and section numbers),
concentrations for water quality parameters including VOCs, physical characteristics (e.g., depth to
water, altitude, depth to the bottom of the open interval), and sample date.
USGS staff report that the most comprehensive VOC data in Idaho are from the INEL site, which is
primarily in Butte County but also falls in parts of Jefferson, Bingham, and Clark counties, and the
Mountain Home Air Force Base site in Elmore County. The USGS has collected VOC data on an on-
going basis from approximately ten wells at the INEL site since 1987 and has received results in the
past year from 75 wells or springs downgradient from the site. USGS has VOC data from Mountain
Home Air Force Base dating from late 1989.
The WQB has VOC data from approximately 40 to 50 UST remedial responses at sites located in the
more densely populated cities in the State. These data are available in hard copy files only and are
maintained in field offices across the State, as well as at the Boise office. The remedial response data
include monitoring information for a variety of organic chemicals such as benzene, toluene, xylene,
and ethylbenzene. WQB has collected these data since 1988 and some data date back to the 1960s.
The WQB also maintains a site characterization data base for the approximately 8000 to 10,000 USTs
in the State. The data base, however, does not contain ground-water monitoring information.
The WQB's office in Coeur d'Alene maintains a ground-water quality data base for its monitoring of the
Rathdrum Prairie sole source aquifer located in Kootenai County. The WQB maintains the Rathdrum
Prairie data in a Lotus 1-2-3 spreadsheet file. The data base tracks a number of parameters including
well location, physical and chemical analytical results including a limited number of VOCs, and the
date samples were taken. The WQB tracks VOCs in the Rathdrum Prairie aquifer from 30 different
wells. It has quarterly monitoring data from these wells since 1975. Staff from the Coeur d'Alene
office, however, expressed concern over the quality of the laboratory analyses of VOCs.
The USFS Intermountain Region also maintains an automated data base of ground-water monitoring
results taken from USFS campground drinking water supplies across its jurisdiction which includes all
but the panhandle region of Idaho. The data base includes, among other elements, analytical
monitoring results for selected VOCs.
A summary of publications containing additional VOC data is presented in Appendix C to this report.
Approach for Characterizing the Indicator
After reviewing the data sources discussed above EPA concluded that data retrievals from the USGS
QWDATA data base would provide the best available information to track trends in VOCs in Idaho.
EPA chose not to include the data bases maintained by WQB since the data bases either were not
automated or did not contain ground-water monitoring information; or, as was the case for the data
concerning the Rathdrum Prairie aquifer, the quality of the laboratory analyses was suspect. The
USFS data base was not selected because the data base was limited to monitoring results from
campground wells located in relatively rural and undeveloped areas. Therefore the USGS QWDATA
data base was used as the sole data source for characterizing the VOC indicator.
EPA chose this automated data base because it is the best data source available in that it provides:
the greatest amount of data in one data base;
the greatest number of sampling locations in one data base;
sampling sites located geographically by latitude and longitude;
12 Personal communication, U.S. Geological Survey, Boise District Office.
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21
the greatest consistency in collecting, analyzing, and reporting data;
the broadest time coverage:
existing personnel support; and
existing documentation.
However, USGS was able to provide data for only a few select counties. Budget constraints
prevented USGS from undertaking a more complete VOC data retrieval. USGS staff reported that
more comprehensive data are available from the relatively more rigorous VOC monitoring programs
undertaken at the INEL and the Mountain Home Air Force Base sites. However, due to the planned
release of the Mountain Home VOC data in March 1991, USGS was unable to make that information
available for this study. As a result, the VOC data included in this report come solely from two
counties (Butte and Jefferson) where USGS is involved in sampling ground water from the INEL site.
The VOC data retrievals from USGS's QWDATA data base for Butte and Jefferson counties included
the following elements for the years 1987 through 1989:
station number;
county FIPS code;
latitude and longitude;
local identifier (township, range, and section numbers);
sample date; and
concentration results for 28 VOCs.
Study Results and Interpretation of Data
Volatile organic compound detections in Butte County rose between 1987 and 1988 and then fell in
1989 to below the 1987 level. Jefferson County exhibited few VOC detections. However, only 72
samples were analyzed in Jefferson County for the period of record, while 5,164 samples were
analyzed in Butte County during the same period. Exhibit C-1 graphically presents the total number of
VOC detections for the two counties for the years 1987 through 1989. As depicted in Exhibit C-2,
sampling and detections in Butte County were at their lowest in 1989 suggesting a positive
relationship between these two factors. However, this relationship is not strong for the years 1987 and
1988, as the number of detections were at their highest in 1988 while the numbers of samples taken
were at their highest in 1987. USGS VOC data for Butte and Jefferson counties are presented in
Exhibit C-1 and in Tables D-1 and D-2 in Appendix D to this report.
Tables D-1 and D-2 in Appendix D also present the number of detections by constituent that
exceeded a health based threshold. The threshold for each constituent is based on either (1) a final
Federal MCL, if available, (2) a proposed Federal MCL, if available, or (3) Federal ambient water
quality criteria, if available. In Butte County, the number of threshold exceedances were at their
highest in 1988 with 20 exceedances, while they were at their lowest in 1989 with five exceedances.
Trichloroethene was responsible for the highest number of threshold exceedances in Butte County.
The pilot study demonstrates that:
VOC data are available at the county level; and
data lend themselves to visual interpretation.
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EXHIBIT C-1
VOC DETECTIONS FOR SELECTED COUNTIES
IN IDAHO
DETECTIONS
160
ro
ro
BUTTE
JEFFERSON
COUNTIES
1987
1988
1989
Source: QWDATA Data Base,
U.S. Geological Survey, Boise District
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EXHIBIT C-2
VOC DETECTIONS FOR BUTTE COUNTY, IDAHO
DETECTIONS
3,000
2,500
ro
1987 SAMPLES TAKEN
1988 DETECTIONS
BUTTE
COUNTIES
1987 DETECTIONS
1989 SAMPLES TAKEN
1988 SAMPLES TAKEN
1989 DETECTIONS
Source: QWDATA Data Base,
U.S. Geological Survey, Boise District
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24
However, the following factors limit the use of the data in meeting the national objective:
VOC data are available for only a small number of well characterized
sites;
VOC data are limited in geographic coverage to only a few Idaho
counties;
a large body of data is available for only a limited period of time; and
consistency in sampling methods and depths may vary over time.
Only broad generalizations regarding the extent of VOC contamination in two counties can be made
from the available data. Furthermore, since USGS VOC data in QWDATA consists of localized studies,
VOC data are not representative of ground-water quality across the State. Therefore, the usefulness
of these data are minimized as indicators of ground-water quality within the counties themselves as
well as across the State.
Revisions to the Indicator Data Collection Process
In order to collect data to meet the national objective and effectively track trends in the 305(b)
reporting environment, the following revisions to the VOC data collection process are recommended:
increase the amount of sampling and analysis across the State;
maintain consistency in sampling methods and analyses; and
sample on a periodic basis, at least annually.
Conclusions
The Idaho VOC data available for this report provide only a snapshot of the extent of VOC
contamination in specific regions of the State. Therefore, the national objective of identifying VOC
levels in ground water across the State cannot be met with the data currently available in Idaho.
D. NITRATES
This section presents the national objectives, approach, and findings of the study of nitrates as an
indicator of area-wide ground-water contamination sources in Idaho.
National Objective
EPA designed the nitrate indicator to support the following national objectives:13
identify the pattern and level of ground-water quality with respect to
the area-wide sources throughout the country by identifying the
geographic pattern of contamination on a county-by-county basis over
a given time span; and
display State-by-State trends over time in the area-wide quality of
ground-water by identifying the number of counties, State-by-state
13 U.S. EPA. Office of Ground-Water Protection, April 1989, "Indicators for Measuring Progress in Ground-Water
Protection," EPA 44016-88-006.
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25
where ground-water concentrations of nitrates are improving versus
those where they are deteriorating.
The following discussion describes the data sources identified in Idaho to address these objectives
and presents and analyses the data results.
Description of the Indicator
Nitrate is commonly found in ground water in regions that are affected by area-wide sources of
contamination, such as agriculture and septic systems. Nitrate can leach into ground water from
normal agricultural practices (e.g., the use of nitrogen fertilizers) and wastewater disposal because of
their high solubility in water and their inability to adsorb to soil particles. The detection of nitrate also
can often indicate the possible presence of other ground-water contaminants. For example, a
correlation between areas susceptible to nitrate contamination and those susceptible to pesticide
contamination has been suggested. This is likely because chemicals that leach into ground water
tend to be water soluble, poorly adsorbed by soil, and have a partial or full negative charge at
ambient pH. Some pesticides (such as the triazine and acetanilide herbicides and carbamate
insecticides) share these properties with nitrates.
Approximately 90 percent of the population in Idaho relies on ground water for drinking water supply,
and in many areas of Idaho, ground water is the only available source of drinking water. As a result,
measuring changes in nitrate concentrations over time may provide a valuable indicator of future
trends in drinking water quality. High nitrate concentrations in drinking water supplies are also a
recognized human health concern, especially for young children. Exposure to high levels of nitrate
can result in methemoglobinemia or 'blue baby syndrome." As a result, the primary drinking water
standard for nitrate has been set at 10 mg/l (as nitrogen).14
Indicator Data Management in Idaho
Data characterizing nitrate levels in Idaho ground water are available from the following four data
bases:
USGS District QWDATA data base;
USFS Intermountain Region campground water quality data base;
USFS Northern Region campground water quality data base; and
Idaho WQB Rathdrum Prairie data base.
The USGS collects ground-water quality data including nitrates from approximately 3,900 well sites
throughout the State. These data are maintained in the QWDATA data base on a USGS District prime
computer in Boise. Data from QWDATA are uploaded from the District prime computer to NWIS on
USGS's main computer approximately once a month. The QWDATA data base tracks a number of
data elements including a well identification number, latitude and longitude, a local identifier (township,
range, and section numbers), concentrations for water quality parameters including nitrates, physical
characteristics (e.g., depth to water, altitude, depth to the bottom of the open interval), and sample
date. Nitrate data are reported to QWDATA as nitrate-nitrogen (dissolved nitrite plus nitrate as
nitrogen). The most comprehensive nitrate data are from the Boise Valley area, the Rathdrum Prairie,
and the Snake River Plain.
The USFS Intermountain Region also maintains an automated data base of ground-water monitoring
results from USFS campground drinking water supplies across its jurisdiction which includes all but
the panhandle region of Idaho. The data base includes several elements including analytical
14 40 CFR Part 141.11
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26
monitoring results for nitrate, lead, fluoride,' and several other inorganic chemicals, plus a number of
organic chemicals and radionuclides as well. The data base also tracks information on the water
system identifier, latitude and longitude, the hydrologic unit and watershed codes, county and State
FIPS codes, the date samples were collected, and the date samples were analyzed. The data base
contains data collected since 1975.
The USFS Northern Region, which covers the panhandle region of Idaho, maintains a similar
campground water quality data base. This data base is not automated. The data base consists of
hard copy laboratory analysis reports that present information on concentrations of several chemical
contaminants including nitrate in ground-water samples collected from USFS campgrounds. The
laboratory reports include the water system name, county name, date sample was collected, and
analytical results. These data have been collected since 1977.
The WQB's office in Coeur d'Alene maintains a ground-water quality data base for its monitoring
results of the Rathdrum Prairie sole source aquifer located in Kootenai County. The WQB maintains
the Rathdrum Prairie data in a Lotus 1 -2-3 spreadsheet file. The data base tracks a number of data
elements including well location using township, range, and section numbers, physical and chemical
analytical results including nitrate, and data samples were taken. The WQB Rathdrum Prairie aquifer
well monitoring network includes 30 separate wells. The data base contains quarterly monitoring data
from these wells dating from 1975. A summary of publications containing additional nitrate data is
presented in Appendix C.
Approach for Characterizing the Indicator
After reviewing the data bases discussed above EPA concluded that data retrievals from the USGS
QWDATA data base, the USFS Intermountain Region data base, and the WQB Rathdrum Prairie data
base would provide the best information on nitrate contamination of ground water in Idaho.
EPA chose these data bases because of their following attributes:
data bases were automated;
data bases together provided geographic coverage not available in
any one data base;
data bases together provided the greatest amount of data;
vast majority of sites in the data bases are located geographically by
latitude and longitude;
data bases have existing personnel support; and
data bases have existing documentation.
The USFS Northern Region data set was not used for purposes of characterizing this indicator
because those data were not automated.
EPA requested nitrate data retrievals from the USGS Boise District QWDATA files for all counties from
1980 through 1989. USGS offered to provide data for a few select counties based on the rationale
that more comprehensive sampling efforts were completed in those counties and would provide more
complete data. Budget constraints prevented USGS from undertaking a more extensive nitrate data
retrieval. The data retrievals by the USGS District staff were made for the Boise Valley area (Ada and
Canyon counties), the Snake River Plain (Cassia and Minidoka counties), and the Rathdrum Prairie
(Kootenai County) for the years 1980 through 1989. The nitrate data retrievals from USGS's QWDATA
data base included the following elements:
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27
station number;
county FIPS code;
latitude and longitude;
local identifier (township, range, and section numbers);
date sample was taken; and
concentration of nitrate-nitrogen (i.e., dissolved nitrite plus nitrate as nitrogen).
The nitrate data retrievals from the USFS Intermountain Region campground water quality data base
included data from the 24 counties for which the USFS region had information. Data were available
for the years 1975 through 1990. The retrievals included the following pertinent data elements:
water system number;
county FIPS code;
latitude and longitude;
hydrologic unit and watershed codes;
date sample was taken;
date sample was analyzed; and
concentration of nitrate as nitrogen.
The nitrate data retrievals from the WQB Rathdrum Prairie data base included data from Kootenai
County for the years 1975 through 1990. Data were available only for Kootenai County since all WQB
Rathdrum Prairie aquifer monitoring wells are located in that county. The nitrate data retrievals
included the following elements:
well identification number;
township, range, and section numbers;
sample date;
field parameters (e.g., temperature, pH); and
concentrations of inorganic chemicals including nitrate as nitrogen.
Study Results and Interpretation of Data
Butte and Cassia counties had the highest number of nitrate detections, as recorded in the USGS
data base (see Exhibit D-1), while Custer County had the greatest number of detections in the USFS
data base in 1984, followed closely by Lemhi County in years 1984 and 1987 (see Exhibits D-2.1
through D-2.3). Exhibit D-3 graphically presents the number of samples analyzed, nitrate detections,
and MCL exceedances reported by the WQB Rathdrum Prairie data base for the years 1980 through
1989. This exhibit shows that nitrate concentrations did not exceed the MCL in any year. However,
whenever samples were taken nitrate was found. Nitrate data from the three data bases are
presented in Tables E-1 through E-3 in Appendix E.
The positive relationship between sampling and detections observed in the Rathdrum Prairie data
base is also evident for the counties in the USGS QWDATA and the USFS data bases as can be seen
in Tables E-1 and E-2.1 through E-2.3. These tables present the following information by county by
year for each data base:
-------
EXHIBIT D-1
NITRATE DETECTIONS FOR SELECTED COUNTIES
IN IDAHO, U.S. GEOLOGICAL SURVEY
DETECTIONS
100
80
60
40
20
0
n
T
t\3
03
H.
ADA
1982
BUTTE
CANYON CASSIA JEFFERSON KOOTENAI MINIDOKA
COUNTIES
1983
1984
1985 0 1986 [H] 1987 £<] 1988
1989
Source: QWDATA Data Base,
U.S. Geological Survey, Boise District
-------
EXHIBIT D-2.1
NITRATE DETECTIONS FOR SELECTED COUNTIES
IN IDAHO, U.S. FOREST SERVICE
DETECTIONS
l
-------
EXHIBIT D-2.2
NITRATE DETECTIONS FOR SELECTED COUNTIES
IN IDAHO, U.S. FOREST SERVICE (continued)
DETECTIONS
30
25
20
15
10
0
n
1
H
CARIBOU CASSIA CLARK
CUSTER ELMORE FRANKLIN FREMONT
COUNTIES
1982
1983
1984
1985 Q 1986 [T| 1987
1988
GEM
1989
Source: U.S. Forest Service
-------
EXHIBIT D-2.3
NITRATE DETECTIONS FOR SELECTED COUNTIES
IN IDAHO, U.S. FOREST SERVICE (continued)
DETECTIONS
25
20
15
10
0
n n F
1H.
,
IDAHO LEMHI TETON VALLEY
JEFFERSON MADISON TWIN FALLS WASHINGTON
COUNTIES
1982
1983
1984
1985
1986 Q 1987 [//] 1988
1989
Source: U.S. Forest Service
-------
EXHIBIT D-3
NITRATE DETECTIONS FOR KOOTENAI COUNTY, IDAHO
WATER QUALITY BUREAU
NUMBER OF DETECTIONS
1980
1981
1982
1983 1984 1985
YEARS
1986
1987
1988
1989
# SAMPLES ANALYZED
# SAMPLE DETECTIONS
# MCL EXCEEDANCES
MCL: 1
Source: Water Quality Bureau's
Rathdrum Prairie Data Base
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33
number of wells samples were drawn from;
number of samples taken and analyzed;
number of samples in which nitrates were detected; and
number of detections exceeding the MCL of 10 mg/l.
For all three data bases, the number of sample detections closely tracked with the number of
analyses. Conversely, low levels of detections were the result of low sampling activity. The tables
also show the wide variation in sampling frequency both within a county over the years as well as
between counties in a single year.
The relationship that existed between sampling and detections in all three data bases, however, did
not have as great an effect on the number of detections exceeding the MCL. It is interesting to note
that the USGS QWDATA data base results in Table E-1 show that the number of MCL exceedances in
Butte County peaked in 1981 with six, then fell to one exceedance in following years despite a
continued high sampling frequency. The highest number of MCL exceedances occurred in Cassia
County in 1987 with 23, while the highest ratio of exceedances to samples taken also occurred in
Minidoka County in 1987. Tables E-2.1 and E-2.2 show there were no MCL exceedances for nitrate
for analyses in the USFS data base which is most likely a result of the low nitrate load found in areas
impacting campground drinking water supplies. Given this, the USFS campground water quality data
base may be a good candidate for providing background ground-water quality data in the State.
A number of conclusions can be drawn regarding the applicability of the data for future 305(b)
reports:
nitrate data are available at the county level;
nitrate data lend themselves to visual representation; and
nitrate data would allow, with time, for comparisons among counties
and within a county across time.
However, the following limitations restrict the ability to characterize significant trends in the nitrate
indicator data:
no one data base contains nitrate data that are representative of the
entire State;
sampling is not consistent in geographic coverage;
sampling is not consistent over time;
repeat sampling of most wells appears to be infrequent;
nonuniformity in securing and analyzing samples is likely across
various data bases; and
consistency in sampling depths is not maintained over time.
Broad generalizations regarding the extent of area-wide nitrate contamination in specific counties can
be made with the available data. However, due to likely inconsistencies present between the different
data bases, the ability to make meaningful comparisons between the data bases is limited.
Furthermore, no one agency has conducted a comprehensive sampling program across the entire
State that will allow an analysis of nitrate concentration trends. For these reasons, as well as those
stated above, the usefulness of the nitrate data collected for this study is minimized as indicators of
area-wide nitrate contamination of ground water within counties themselves, as well as across the
State.
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34
Revisions to the Indicator Data Collection Process
In order to collect data to meet the national objective of this indicator and effectively track trends in
the 305(b) reporting environment, the following recommendations are presented based on the
experience gained in this pilot study:
identify and establish an ambient monitoring well network that is
consistent statewide;
use data bases that are maintained by one office;
develop and use a standard data collection format;
sample on a periodic basis, at least annually;
maintain consistency in sampling; and
maintain consistency in sample analyses.
Conclusions
The Idaho nitrate data available for this report provide an indication of the extent of nitrate
contamination in the State's ground water. The data allow for county-level comparisons. However,
because the data were collected and maintained by different agencies, the validity of these
comparisons is suspect. Nonetheless, sufficient data are available to at least partially address the
national objectives.
E. EXTENT OF AGRICULTURAL PESTICIDE USE
This section presents the national objectives, description, and approach for characterizing this
indicator in Idaho.
National Objective
EPA designed the agricultural pesticide use indicator to support the following objectives:15
identify the relative intensity of pesticide use on a county-by-county basis;
identify the relative vulnerability to ground-water contamination on a county-by-county
basis; and
provide an indication of where potential ground-water problems from pesticide use
might occur, based on geographic patterns of use and vulnerability.
The following discussion describes the manner in which this study was able to address the objectives
with agricultural pesticide usage data collected in Idaho.
Description of the Indicator
The use of pesticides, primarily associated with agricultural practices, has been identified as a
potential source of ground-water degradation. The potential degradation of ground water due to the
application of pesticides in Idaho is an important issue for the following reasons:
15 U.S. EPA, Office of Ground-Water Protection, April 1989, "Indicators for Measuring Progress in Ground-Water
Protection." EPA 44016-88-006.
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35
approximately 90 percent.of Idaho's drinking water is supplied by ground water;
the diversity of agricultural crops has a corresponding diversity in the amounts and
types of pesticides used; and
many agricultural chemicals are also used in residential areas.
Indicator Data Management in Idaho
No data pertaining to the agricultural use of pesticides on either a statewide or regional basis were
found in Idaho. The State has also not been able to provide any pesticide use or purchase
information on a statewide or regional basis. Therefore, no data were collected to assess the extent of
contamination from this indicator of ground-water quality.
Revisions to the Indicator Data Collection Process
In order to collect pesticide use data to meet the national objective of this indicator it is recommended
that the State develop an automated data base on pesticide use and/or purchase information.
Although no such data base currently exists, the State has an excellent opportunity to design a
system that provides high quality information that can easily be used for future 305(b) reporting as
well as meeting its own requirements.
F. ADDITIONAL INDICATORS IDENTIFIED BY IDAHO PERSONNEL
No additional ground-water indicators were identified by Idaho personnel.
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-------
37
IV. STUDY CONCLUSIONS
EPA conducted this pilot study to determine whether the criteria for reporting ground-water indicators,
as developed by the EPA workgroup, could be met with data collected for the State of Idaho. These
criteria include the following:16
indicators should be based on actual data measurement;
indicators should lend themselves to graphic display to convey trends
and other information readily;
whenever possible, existing data should be used rather than requiring
new data collection;
data should be collected over time at the same locations; and
data can have limitations and still be useful as an 'indicator' of ground-
water problems or progress.
In general, this study found that data characterizing four of the five indicators are available and that
these data lend themselves to graphic display, as depicted in this report. Due to the lack of pesticide
data collected by Idaho, no data on this indicator is available for presentation or discussion in this
report.
EPA used only existing data for this analysis, although EPA noted that additional data collection could
better characterize several of the indicators. EPA also found that much of the ground-water
monitoring data compiled for this study did not fully support trend analyses because samples were
not always taken from the same locations over time. Nonetheless, EPA concluded that if the
limitations are understood, data are available for Idaho to at least partially characterize four of the five
ground-water indicators. The following discussion presents specific conclusions relating to the data
collected for each of the indicators.
Maximum Contaminant Levels: Data from the FRDS-II data base are sufficient to support the national
objectives for this indicator. However, Idaho personnel report uncertainties in the quality of the
available data. Although EPA limited the analysis presented in this study to county-level summaries of
MCL violation information, the analysis could be organized at different geographic levels and could
include analyses of the populations potentially at risk from the violations. The population data
maintained in FRDS, however, may not accurately reflect size of the population exposed to a particular
MCL violation.
On-Site and Off-Site Contamination at Hazardous Waste Sites: Sufficient data are available in
RCRA and CERCLA site files to characterize the level of contamination, the status of off-site
contaminant migration, and the populations at risk for specific areas. However, Idaho has not
recorded the data in a State-wide automated data management system. Therefore, EPA had to
manipulate the data manually to present it in a format useful for 305(b) reports. Due to the relatively
labor intensive effort required to manually manipulate the data, EPA analyzed the data from only a few
hazardous waste sites. Therefore, the on-site and off-site hazardous waste site data collected for this
report represent only a "snapshot" of the extent of contamination at the waste sites.
16 U.S. EPA, Office of Ground-Water Protection, April 1989, "Indicators for Measuring Progress in Ground-Water
Protection," EPA 44016-88-006.
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38
Volatile Organic Compounds: EPA accessed data maintained in the USGS QWDATA base to
characterize the VOC indicator." Although USGS was able to provide data for only a few select
counties, EPA was able to organize this data at the county level and display trends in VOC levels
graphically. However, because VOC data in the QWDATA bases were limited to only a small number
of well characterized sites, EPA determined that the limited geographic distribution of the VOC
analyses limited the usefulness of the data to support a State analysis. A more thorough and
consistent VOC sampling and analysis program could be developed to better support analyses of
trends in VOC levels State-wide.
Nitrates: EPA accessed data maintained in the USGS QWDATA data base, the USFS Intermountain
Region data base, and the WQB Rathdrum Prairie data base. Multiple data bases were utilized to
characterize the nitrate indicator since, individually the three data bases did not have sufficient
geographic coverage. EPA was able to organize the data at the county level and display trends in
nitrate levels graphically. Because the data were collected and maintained by different agencies,
however, the validity of comparisons should be reviewed. Nonetheless, EPA has concluded that
sufficient data are available to at least partially address the national objectives.
Pesticide Use: No data are available in Idaho to characterize this indicator. Therefore, EPA could not
collect data to access the extent of contamination from this indicator of ground-water quality. The
State may wish to begin collecting information on use of pesticides for indicator reporting.
The following discussion presents a summary of the general lessons learned during the course of this
pilot study. The discussion first addresses the technical issues and data management practices
encountered in this pilot study. The discussion then outlines suggested revisions to these existing
practices that can be adopted by the State to better support future ground-water indicator reporting.
Finally, the resources needed to support further indicator reporting and next steps are briefly
discussed.
A. EXISTING PRACTICES
In completing this pilot study, EPA encountered a number of problems relating to the quality and
availability of the compiled data which limit their application to support the indicator objectives. The
problems concerning the quality of the data related both to the representativeness or geographic
coverage of the data and to the procedures used to collect the analytical results. In particular, EPA
identified the following technical issues:
there is an insufficient volume of data for some indicators;
data are limited in geographic coverage;
sampling is not consistent in geographic coverage;
sampling is not consistent over time;
securing and analyzing samples was not uniform;
limited repeat sampling is conducted at the same location; and
sampling depths vary.
In addition to these technical issues, EPA also identified problems with regard to the way in which the
collected data were managed. These data management issues limited EPA's ability to access and
use the information provided by the State:
missing annual data or other gaps were not explicitly identified;
data bases were originally organized to support objectives that differ from those the
indicators were designed to address; and
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39
different agencies were responsible for data presented, leading to potential
inconsistencies.
B. SUGGESTED REVISIONS TO EXISTING PRACTICES TO SUPPORT INDICATOR
REPORTING
EPA is strongly promoting the wider use of indicator data collection across all Federal and State
programs. An EPA Task Force, with State participation, developed concrete principles and objectives
to ensure effective and -consistent decision-making in all Agency decisions affecting ground water, and
will also institute State Comprehensive Ground-Water Protection Programs17. Monitoring and data
collection is one area that will be addressed.
As Idaho continues its monitoring and data collection efforts and begins to develop its comprehensive
program, it is important to keep the issues noted in the pilot study in mind. For example, sampling
and analytical consistency may be promoted by establishing consistent scientific and data collection
protocols and by promoting the development of ground-water monitoring networks, as appropriate, to
provide trend data. Data management activities that employ standard data collection formats for each
of the indicators are already underway in Idaho to maintain standard data management protocols
between agencies. Cooperative efforts between EPA and Idaho will ensure that information collection
activities support the objective of protecting the nation's ground-water resources.
To begin moving toward data consistency, EPA, with States and other Federal agency work group
participants developed a set of the most critical data elements for ground-water quality information.
These data elements form the foundation upon which ground-water data users may build their own
data base, adding elements to meet their specific needs. The use of this minimum set of data
elements (MSDE) will ensure that EPA and the State can share and manipulate ground-water data
to support better environmental decision-making, and facilitate cross-program integration.
Once adopted, these revisions will support the collection, management, and reporting of indicator data
necessary for future 305(b) reports.
C. RESOURCES FOR IMPLEMENTING
Initially, the resources required at the State level to implement national indicator reporting may be
extensive. Idaho cannot significantly improve it data collection and reporting without expending the
necessary resources to correct deficiencies. As the State establishes monitoring networks and
integrates their information systems, data will become more accessible for use in indicator
development. Furthermore, after the information is collected and the data elements and data
reporting formats for including ground-water indicators in 305(b) reports are identified and applied, the
effort expended for completing the 305(b) report will be greatly reduced.
D. NEXT STEPS
This pilot study is one of three studies EPA completed investigating the use of ground-water indicators
in 305(b) reports. A Findings Report has been prepared which outlines and summarizes the
information and knowledge gathered in Idaho, Minnesota, and New Jersey. The Findings Report also
17 U.S. EPA, Office of the Administrator, "Protecting the Nation's Ground Water: EPA's Strategy for the 1990s,"
EPA21Z-1020, (Washington, D.C.) July 1991.
18 U.S. EPA, Office of Ground Water and
Ground-Water Quality." (Washington, D.C.) July 1991 (draft final)
18 U.S. EPA, Office of Ground Water and Drinking Water, "Definitions for the Minimum Set of Data Elements for
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40
makes recommendations regarding the implementation of indicators in future 305(b) reports. Based
on these recommendations, EPA is developing a Technical Assistance Document (TAD)19 to provide
technical guidance to the States on how to gather and use indicator data as part of their 1992 305(b)
Reports. The TAD is also intended to help set the stage for those States that are moving toward
developing comprehensive ground-water monitoring and information systems, particularly in
relationship to ground-water indicator reporting, and to assist those which are already in the process.
The TAD is expected to be completed by early 1992.
19 U.S EPA, Office of Ground Water and Drinking Water, "Technical Assistance Document," (Washington, DC.)
September 1991 (draft).
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41
BIBLIOGRAPHY
Bureau of Indian Affairs, 1983. Map of Portland Area Jurisdiction.
Bureau of Indian Affairs, 1977. Map of Duck Valley Indian Reservation, Owyhee County, Idaho.
Bureau of Land Management, 1982. Map of Surface Management Responsibility, State of Idaho.
Bureau of Reclamation, Pacific Northwest Division, 1984. Boise Valley Shallow Ground Water Quality
Study.
Bureau of Reclamation, 1983. Water Quality Studies Payette Division Boise Project, Idaho -
Phosphorous Loading & Bacterial Contamination of Cascade Reservoir.
Idaho Water and Energy Resources Research Institute, University of Idaho, 1984. Impact of Individual
On-Site Sewage Disposal Facilities on Mountain Valleys - Phase II - Water-Quality
Considerations.
Idaho Water and Energy Resources Research Institute, University of Idaho, 1982. Impacts of Individual
On-Site Sewage Disposal on Mountain Valleys - Phase I.
State of Idaho, Department of Health and Welfare, 1990. Sampling Results from the Fruitland and
Weiser studies. Water Quality Bureau.
State of Idaho, Department of Health and Welfare, (date unknown). Sate of Idaho Map of Idaho Public
Health Districts.
State of Idaho, Department of Health and Welfare, 1990 Rock Creek Rural Clean Water Program
Comprehensive Water Quality Monitoring Annual Report. Water Quality Bureau.
State of Idaho, Department of Health and Welfare. Rathdrum Prairie Monitoring Data. IBM-PC
diskettes containing Lotus 1-2-3 worksheets. Water Quality Bureau.
State of Idaho, Department of Health and Welfare, 1988. Idaho Water Quality Status Report and
Nonpoint Assessment.
State of Idaho, Department of Water Resources, 1988. A Study of Potential Impacts on Ground-Water
Quality From Agricultural Injection Wells in the Gooding Area, Idaho.
State of Idaho, Department of Water Resources, 1987. A Study of Potential Impacts on Ground-Water
Quality From Injection Wells in the West Bonneville County Area, Idaho.
State of Idaho, Department of Water Resources, 1982. Concentrations of Pesticide in Irrigation Return
Flows Influent to Waste Disposal Wells in Southern Idaho.
State of Idaho, Department of Water Resources, 1978. List of Publications.
U.S. EPA, Region X, 1988-1989. Ground-Water Environmental Indicator Data for Idaho CERCLA Sites.
Office of Ground Water.
U.S. EPA, 1989. Guidelines for the Preparation of the 1990 State Water Quality Assessment (305(b)
Report).
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42
U.S. EPA, Office of the Administrator, 1991. Protecting the Nation's Ground Water: EPA's Strategy for
the 1990s, EPA 21Z-1020.
U.S. EPA, Office of Ground Water and Drinking Water, 1991 (draft final). Definitions for the Minimum
Set of Data Elements for Ground-Water Quality.
U.S. EPA, Office of Ground-Water Protection, 1989. Indicators for Measuring Progress in Ground-Water
Protection, EPA 44016-88-006.
U.S. Forest Service, 1988. Map of National Forests of the Intermountain Region.
U.S. Forest Service, 1983. Map of the Northern Region, Idaho, Montana, North Dakota, South Dakota,
and Washington.
U.S. Forest Service, 1981. Map of Salmon National Forest (Cobalt, North Forke, Leadore and Salmon
Ranger Districts), Idaho - Montana.
U.S. Geological Survey, 1989. Selected Ground-Water Quality Data for the Southern Part of the Fort
Hall Indian Reservation, Southeastern Idaho. Open-File Report 89-593.
U.S. Geological Survey, 1989. Selected Water-Quality Data for the Rathdrum Prairie Aquifer, North
Idaho. Open-File Report 88-703.
U.S. Geological Survey, 1988. Radionuclides in Ground Water at the Idaho National Engineering
Laboratory, Idaho.
U.S. Geological Survey, 1988. Selected Water-Quality Data for the Fort Hall Indian Reservation,
Southeastern Idaho. Open-File Report 88-496.
U.S. Geological Survey, 1988. Concentrations of Nine Trace Metals in Ground Water at the Idaho
National Engineering Laboratory, Idaho. Open-File Report 88-332.
U.S. Geological Survey, 1987. Purgeable Organic Compounds in Ground Water at the Idaho National
Engineering Laboratory, Idaho. Open-File Report 87-766.
U.S. Geological Survey, 1987. Selected Water-Quality Data for Murtaugh Lake Area, South-Central
Idaho. Open-File Report 87-466.
U.S. Geological Survey, 1987. Selected Water-Quality Data for the Minidoka Irrigation District South-
Central Idaho. Open-File Report 87-465.
U.S. Geological Survey, 1987. Selected Water-Quality Data for the Burley Irrigation District, South-
Central Idaho. Open-File Report 87-240.
U.S. Geological Survey, 1987. Quality of Ground Water in Idaho. Water-Supply Paper 2272.
U.S. Geological Survey, 1986. Compilation of References on Geology and Hydrology of the Snake
River Drainage Basin Above Weiser, Idaho. Open-File Report 86-245.
U.S. Geological Survey, 1985. National Water Summary 1984. Water-Supply Paper 2275.
U.S. Geological Survey, 1985. Directory of Groundwater Information in Idaho. Water Resources
Division.
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43
U.S. Geological Survey, 1982. Compilation of Ground-Water Quality Data for Selected Wells in Elmore
Owyhee, Ada, and Canyon Counties, Idaho, 1945 Through 1982. Open-File Report 83-39.
U.S. Geological Survey, 1974. Hydrologic Unit Map -1974, State of Idaho.
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APPENDIX A: SUMMARY DATA FOR MCL VIOLATIONS FOR
SELECTED COUNTIES IN IDAHO
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Table A-1: Number of MCL Violations for Nitrate for Selected Counties in Idaho
COUNTY
ADA
BANNOCK
BONNEVILLE
BUTTE
CANYON
CASSIA
JEFFERSON
KOOTENAI
MINIDOKA
TWIN FALLS
TOTALS
YEAR
1980
0
0
0
0
0
0
0
0
0
0
0
1981
0
2
0
0
0
0
0
0
0
1
3
1982
0
2
0
0
0
0
0
0
0
1
3
1983
0
2
0
0
1
0
0
0
0
0
3
1984
0
2
0
0
1
0
0
0
0
0
3
1985
0
0
0
0
1
0
0
0
0
0
1
1986
0
0
0
0
0
0
0
0
0
0
0
1987
0
0
0
0
0
0
0
0
0
0
0
1988
0
0
0
0
0
0
0
0
0
0
0
1989
0
0
0
0
0
0
0
0
0
0
0
MCL: 10mg/L
Source. Federal Reporting Data System (FRDS-II), U.S. Environmental Protection Agency
-------
Table A-2: Number of MCL Violations for Total Coliforms for Selected Counties in Idaho
COUNTY
ADA
BANNOCK
BONNEVILLE
BUTTE
CANYON
CASSIA
JEFFERSON
KOOTENAI
M1NIDOKA
TWIN FALLS
TOTALS
YEAR
1980
20
20
8
4
13
13
2
30
3
Id
123
1981
28
42
12
4
12
13
2
53
5
12
183
1982
23
34
17
0
11
6
3
44
3
14
155
1983
20
33
13
3
15
9
5
50
1
18
167
1984
21
42
7
3
11
25
6
29
4
24
172
1985
17
23
4
0
8
8
3
24
1
14
102
1986
15
4
11
0
9
14
0
28
3
10
94
1987
7
13
15
2
16
4
4
25
2
9
97
1988
21
9
13
3
19
5
2
42
3
9
126
1989
28
22
38
5
22
2
6
43
4
7
177
MCL: 1/100 ml
Source: Federal Reporting Data System (FRDS-II), U.S. Environmental Protection Agency
-------
Table A-3: Number of MCL Violations for Gross Alpha Particle Activity for Selected
Counties in Idaho
COUNTY
ADA
BANNOCK
BONNEVILLE
BUTTE
CANYON
CASSIA
JEFFERSON
KOOTENAI
MINIDOKA
TWIN FALLS
TOTALS
YEAR
1980
0
0
0
0
0
0
0
0
0
0
0
1981
2
0
0
0
1
0
0
0
0
0
3
1982
1
0
0
0
1
0
0
0
0
0
2
1983
1
0
0
0
1
0
0
0
0
0
2
1984
1
0
0
0
1
0
0
0
0
0
2
1985
0
0
0
0
0
0
0
0
0
0
0
1986
0
0
0
0
0
0
0
0
0
0
0
1987
0
0
0
0
0
0
0
0
0
0
0
1988
0
0
0
0
0
0
0
0
0
0
0
1989
0
0
0
0
0
0
0
0
0
0
0
MCL: 15pCi/L
Source: Federal Reporting Data System (FRDS-II), U.S. Environmental Protection Agency
-------
Table A-4: Number of MCL Violations for Fluoride for Selected Counties in Idaho
COUNTY
ADA
BANNOCK
BONNEVILLE
BUTTE
CANYON
CASSIA
JEFFERSON
KOOTENAI
MINIDOKA
TWIN FALLS
TOTALS
YEAR
1980
0
0
0
0
0
0
0
0
0
0
0
1981
0
1
0
0
0
0
0
0
0
0
1
1982
0
1
0
0
0
0
0
0
0
0
1
1983
0
1
0
0
0
0
0
0
0
0
1
1984
0
1
0
0
0
0
0
0
0
0
1
1985
0
0
0
0
0
0
0
0
0
0
0
1986
0
0
0
0
0
0
0
0
0
0
0
1987
0
0
0
0
0
0
0
0
0
0
0
1988
0
0
0
0
0
0
0
0
0
0
0
1989
0
0
0
0
0
0
0
0
0
0
0
MCL: 4.0mg/L
Source. Federal Reporting Data System (FRDS-II), U.S. Environmental Protection Agency
>
01
-------
APPENDIX B: SUMMARY DATA OF HAZARDOUS WASTE SITE
CONTAMINATION CONCENTRATION LEVELS
-------
Exhibit B-1: Summary of Hazardous Waste Site Contamination Concentration Levels
SITE NAME
MORRISON-
KNUDSEN
PACIFIC HIDE
&FUR
PACIFIC HIDE
&FUR
UNION PACIFIC
UNION PACIFIC
INEL
KERR MC GEE
ARRCOMM
ARRCOMM
ENVIROSAFE
SERVICES A
BUNKER HILL
BUNKER HILL
COUNTY
ADA
BANNOCK
BANNOCK
BANNOCK
BANNOCK
BUTTE
CARIBOU
KOOTENAI
KOOTENAI
OWYHEE
SHOSHONE
SHOSHONE
YEAR
1990
1988
1989
1988
1989
1989
1989
1989
1989
1990
1988
1989
TOTAL
PCBs
0
X
X
2
1
X
X
X
X
X
X
X
X
X
X
10
2
0
3
0
CONCENTRATION LEVELS
PESTICIDES
0
X
X
2
1
X
X
X
X
X
X
X
X
X
X
10
2
0
3
0
SYNTHETIC
ORGANICS
0
X
1
1
X
X
X
X
X
X
X
7
2
0
3
X
X
X
X
4
METALS
0
0
1
X
X
X
X
4
2
X
X
X
X
4
3
X
X
X
X
4
BACTERIA
0
X
X
X
X
X
X
X
X
8
1
X
X
X
X
4
2
0
3
0
POP.
WITHIN 3
MILES
10,000
44,900
45,000
44,900
45,000
1,000
3,000
6,300
6,300
20
5,000
5,000
225,420
CONTAMINATION
REACHING
WELLS
NO
NO
NO
UNKNOWN
UNKNOWN
YES
UNKNOWN
NO
NO
NO
UNKNOWN
YES
CD
fo
Source: U.S. EPA Region X and Idaho Hazardous Materials Bureau
Concentration Levels
0 unknown/not analyzed
1 at/below detection limit
2 above detection limit
3 above MCL or other action level
-------
APPENDIX C: SUPPLEMENTARY PUBLICATIONS ON
NITRATE AND VOC DATA
-------
C-2
Several publications (primarily USQS reports) are available that contain relevant nitrate and VOC data.
Some of these publications may contain data that were presented from the data bases described in
the body of this report. Thus, there may be some duplication of data. A number of supplementary
publications are listed below:
"Compilation of Ground-Water Quality Data for Selected Wells in Elmore, Owyhee, Ada, and
Canyon Counties, Idaho, 1945 through 1982,' U.S. Geological Survey, Open-File Report 83-
39.
The report contains well inventory and ground water quality data for 665 sites, including a total of
1,318 chemical analyses. Data are sorted by water temperature (classified as either thermal or
nonthermal). Data from 1980 to 1982 were collected during two reconnaissance ground water quality
studies as part of an Idaho Department of Water Resources program. Pre-1980 data were compiled
from U.S. Geological Survey, U.S. Bureau of Land Management, and Idaho Department of Water
Resources records.
Selected Water-Quality Data for the Burley Irrigation District, South-Central Idaho, March-April,
1987,' U.S. Geological Survey Open-File Report 87-240, by H.W. Young, D.J. Parliman, and
M.L Jones.
This study determined the concentrations of nitrogen compounds in ground water in the Burley
Irrigation District. On-site determinations of ground-water depth, specific conductance, pH, water
temperature, and a check for the presence of several dissolved elements were made at the 114 wells
that were inventoried, and the results were statistically analyzed.
Selected Water-Quality Data for the Murtaugh Lake Area, South-Central Idaho, June, 1987,'
U.S. Geological Survey Open-File Report 87-466, by H.W. Young and D.J. Parliman.
This study determined the concentrations of nitrogen compounds in ground water in the Murtaugh
Lake area. On-site determinations of ground-water depth, specific conductance, pH, water
temperature, and a check for the presence of several dissolved elements were made at the 45 wells
that were inventoried, and the results were statistically analyzed.
Selected Water-Quality Data for the Fort Hall Indian Reservation, Southeastern Idaho, July,
1988,* U.S. Geological Survey Open-File Report 88-496, by H.W. Young and D.J. Parliman.
This study determined the concentrations of nitrogen compounds in ground water in the Fort Hall
Indian Reservation. On-site determinations of ground water depth, specific conductance, pH, water
temperature, and a check for the presence of several dissolved elements were made at the 60 wells
that were inventoried, and the results were statistically analyzed.
Selected Water-Quality Data for the Rathdrum Prairie Aquifer, North Idaho, September, 1988,'
U.S. Geological Survey Open-File Report 88-703, by M.L Jones, H.W. Young and D.J.
Parliman.
This study determined the concentrations of nitrogen compounds in ground water in the Rathdrum
Prairie Aquifer. On-site determinations of ground water depth, specific conductance, pH, water
temperature, and a check for the presence of several dissolved elements were made at the 59 wells
that were inventoried, and the results were statistically analyzed.
'Selected Ground-Water Quality Data for the Southern part of the Fort Hall Indian Reservation,
Southeastern Idaho, July, 1989,' U.S. Geological Survey Open-File Report 89-593, by H.W.
Young and D.J. Parliman.
This study determined the concentrations of nitrogen compounds in ground water in the Fort Hall
Indian Reservation. On-site determinations of ground water depth, specific conductance, pH, water
-------
C-3
temperature, and a check for the presence of several dissolved elements were made at the 56 wells
that were inventoried, and the results were statistically analyzed.
Impacts of Individual On-Site Sewage Disposal Facilities on Mountain Valleys - Phase I,'
Research Technical Completion Report A-084-IDA, by S.P. Luttrell and C.E. Brockway,
December 1982.
This report examines the effect that individual on-site sewage disposal facilities will have on the
ground water of the upper and middle Big Wood River Valley. Because of large scale population
growth in rural areas, individual disposal facilities will soon be widely implemented, and are expected
to increase the output (at the level of maximum projected development) of nitrate to 95,000 pounds
per year, and the output of phosphate to 17,000 pounds per year.
Impacts of Individual On-Site Sewage Disposal Facilities on Mountain Valleys - Phase II -
Water Quality Considerations,1 Research Technical Completion Report, by S.P. Luttrell and
C.E. Brockway, May 1984.
As a continuation of the above report (b), this report evaluated the hydrologic characteristics of the
Big Wood river and aquifer system, addressing ground-water characteristics, ground/surface water
relationships, and water quality. Ground water was determined to be unconfined and close to the
land surface. Monitoring results from 60 wells obtained between July and August of 1983 were used
to determine the concentrations of nitrate, chloride, and orthophosphate. A water table contour map
and a ground/surface water profile were also constructed, and used to indicate a link between ground
and surface water.
'Concentrations of Pesticide in Irrigation Return Flows Influent to Waste Disposal Wells in
Southern Idaho," by LJnford J. Campbell, April 1982.
Over 100 ground water samples were collected in the Minidoka County and Idaho Falls areas in Idaho,
and were analyzed by gas chromatography for 95 pesticides and breakdown products. Of the 95
compounds, 18 were detected in the ground water, but none of them exceeded the established
drinking water standards or proposed water quality criteria
'A Study of Potential Impacts on Ground-Water Quality from Injection Wells in the West
Bonneville County Area, Idaho,' by LJnford J. Campbell, April 1987.
This report studied the impact of 26 injection wells (used in the Idaho Falls area to dispose of
agricultural and urban runoff) and 20 domestic wells on water quality. Ground water depth and rate of
flow were measured, and ground-water samples were taken and analyzed for quality measurements.
The author determined that (1) the regional ground-water flow is to the west, (2) substantial
fluctuations in ground-water level occur due to irrigation, and (3) that ground water and injected
wastewater quality meet State standards.
'A Study of Potential Impacts on Ground-Water Quality from Agricultural Injection Wells in the
Gooding Area, Idaho,' by LJnford J. Campbell, April 1988.
This report studied the impact of 14 injection wells (used in the Gooding area to dispose of
agricultural and urban runoff) and nine domestic wells on water quality. Ground water depth and rate
of flow were measured, and ground water samples were taken and analyzed for quality
measurements. It was determined that (1) the regional ground water flow is to the southwest, and (2)
that substantial fluctuations in ground water level occur due to irrigation. Although ground water
quality meets State standards, five of the agricultural wells were determined to exceed State standards
for total or fecal coliform bacteria, or turbidity.
'Phosphorous Loading & Bacterial Contamination of Cascade Reservoir,' by David W. Zimmer,
Boise Project Power & Modification Study, August 1983.
-------
CM
This report studied the water quality problems associated with the Cascade Dam and Reservoir. Algal
blooms were found to reduce the aesthetic qualities of Cascade Reservoir and increase the risk of
dissolved oxygen problems, while serving as a food base for an Idaho fishery. The prevention of
further increases in phosphorous loading (into the bottom sediments from nonpoint source runoff) was
decided to be the best solution to the problem without harming the fishery.
'Boise Valley Shallow Ground Water Quality Study,' Bureau of Reclamation, Boise, Idaho 1984.
The quality of shallow ground water entering and leaving two residential areas in west Boise was
monitored over a six year period to determine the effect of extensive septic tank disposal systems.
Results indicated that some septic systems had inadequate drainage, and that the average
concentrations of nutrient parameters, phosphorous, chloride, and nitrate increased as they passed
through the area. Data from 1977 through 1983 have been entered into STORET and the wells have
since been turned over to Idaho WQB. WQB has since sampled the wells in 1983, 1989, and 1990.
WQB data is available in hard copy format only.
'Rock Creek Rural Clean Water Program Comprehensive Water Quality Monitoring Annual
Report 1989,' by Terry Maret, Idaho Department of Health and Welfare.
This report presents water quality measurements of the Rock Creek. Results show a decrease in
suspended sediment although suspended sediment levels are still a problem. The water quality index
shows continued improvement, as does the concentration of various chemicals. Although pesticides
were detected, no trends were visible. The impact on trout spawning is still under analysis.
Agricultural Nonpoint Source Studies in Fruitland and Weiser, Idaho. 1990.
The Idaho Water Quality Bureau is conducting two one-time sampling studies of agricultural nonpoint
source impacts on water quality. The study areas cover approximately 10 square miles each near the
towns of Fruitland and Weiser, Idaho. Data for both studies are maintained in word processing files.
Data from the Fruitland study are from 1986 and include concentration levels for nitrate and Dacthal.
Results show that two nitrate samples out of 18 resulted in an exceedance of the MCL Data from the
Weiser study are from 1989 and include data on nitrate and several pesticides. Results show that
eight nitrate samples out of 16 resulted in an exceedance of the MCL for nitrate.
-------
APPENDIX D: SUMMARY OF VOLATILE ORGANIC COMPOUND DETECTIONS
FOR BUTTE AND JEFFERSON COUNTIES, IDAHO
-------
Table D-1: VOC Detections for Butte County, Idaho
(1)
(1)
(2)
NT
NT
NT
(2)
NT
(2)
(2)
(2)
NT
0)
NT
(1)
NT
(1)
0)
(2)
(3)
(2)
(2)
(2)
NT
VOLATILE ORGANIC CHEMICAL
BENZENE
CARBON TETRACHLORIDE
CHLOROBENZENE
CHLOROETHANE
CIS 1,3-DICHLOROPROPENE
DICHLORODIFLUOROMETHANE
ETHYLBENZENE
METHYLCHLORIDE
METHYLENE CHLORIDE
TETRACHLOROETHENE
TOLUENE
TRANS 1,3-DICHLOROPROPENE
TRICHLOROETHENE
TRICHLOROFLUOROMETHANE
VINYL CHLORIDE
1 ,1-DICHLOROETHANE
1.1-DICHLOROETHENE
1 .1 ,1 -TRICHLOROETHANE
1 ,1 ,2-TRICHLOROETHANE
1 ,1 ,2,2-TETRACHLOROETHANE
1 ,2-DICHLOROBENZENE
1 ,2-DICHLOROPROPANE
1 ,2-TRANS-DICHLOROETHENE
2-CHLOROETHYL VINYL ETHER
TOTALS
1987
No.
Well
(A)
76
76
76
76
76
76
76
76
76
76
76
76
76
76
76
76
76
76
76
76
76
76
76
76
No.
Sam
Takn
Anlz
(B)
102
102
102
102
102
102
102
102
102
102
102
102
102
102
102
102
102
102
102
102
102
102
102
102
2448
No.
Sam
Dels
(C)
0
15
0
0
0
2
0
0
0
8
15
0
30
2
0
2
4
31
0
1
1
1
2
0
114
No.
Dets
Exc
HBT
(D)
0
2
0
NT
NT
NT
0
NT
0
2
0
NT
6
NT
0
NT
1
1
0
1
0
1
1
NT
15
1988
No.
Well
(A)
20
20
20
20
20
20
20
20
20
20
20
20
20
20
20
20
20
20
20
20
20
20
20
20
No.
Sam
Takn
Anlz
(B)
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
1536
No.
Sam
Dets
(C)
3
27
0
0
0
10
2
0
2
11
8
0
28
1
2
6
4
29
1
0
2
1
7
0
144
No.
Dets
Exc
HBT
(D)
0
2
0
NT
NT
NT
0
NT
0
4
0
NT
4
NT
2
NT
3
2
0
0
0
1
2
NT
20
1989
No.
Well
(A)
20
20
20
20
20
20
20
20
20
20
20
20
20
20
20
20
20
20
20
20
23
20
20
20
No.
Sam
Takn
Anlz
(B)
49
49
49
49
49
49
49
49
49
49
49
49
49
49
49
49
49
49
49
49
53
49
49
49
1180
No.
Sam
Dets
(C)
2
25
0
0
0
6
1
0
1
4
5
0
28
0
0
2
1
22
1
0
0
0
2
0
100
No.
Dets
Exc
HBT
(D)
0
0
0
NT
NT
NT
0
NT
0
1
0
NT
2
NT
0
NT
1
0
0
0
0
0
1
NT
5
Source: QWDATA Data Base. U.S. Geological Survey, Boise District
(1) Health Based Threshold (HBT) is based on Final Federal MCL
(2) HBT is based on Proposed Federal MCL
(3) HBT is based on Federal Ambient Water Quality Criteria
NT No HBT Available
(A) Number of Wells
(B) Number of Samples Taken and Analyzed
(C) Number of Sample Detections
(D) Number of Detections that Exceed the HBT
-------
Table D-2: Summary of VOC Detections for Jefferson County, Idaho
(1)
(1)
(2)
NT
NT
NT
(2)
NT
(2)
(2)
(2)
NT
0)
NT
0)
NT
(1)
0)
(2)
(3)
(2)
(2)
(2)
NT
VOLATILE ORGANIC CHEMICAL
BENZENE
CARBON TETRACHLORIDE
CHLOROBENZENE
CHLOROETHANE
CIS 1,3-DICHLOROPROPENE
DICHLORODIFLUOROMETHANE
ETHYLBENZENE
METHYLCHLORIDE
METHYLENE CHLORIDE
TETRACHLOROETHENE
TOLUENE
TRANS 1.3-DICHLOROPROPENE
TRICHLOROETHENE
TRICHLOROFLUOROMETHANE
VINYL CHLORIDE
1.1-DICHLOROETHANE
,1-DICHLOROETHENE
,1 ,1-TRICHLOROETHANE
,1 ,2-TRICHLOROETHANE
,1 ,2.2-TETRACHLOROETHANE
,2-DICHLOROBENZENE
,2-DICHLOROPROPANE
,2-TRANS-DICHLOROETHENE
2-CHLOROETHYL VINYL ETHER
TOTALS
No.
Well
(A)
t
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1987
No.
Sam
Takn
Anlz
(B)
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
24
No.
Sam
Dets
(C)
0
0
0
0
0
0
0
0
0
1
0
1
0
0
0
0
0
0
0
0
0
0
0
0
2
No.
Dets
Exc
HBT
(D)
0
0
0
NT
NT
NT
0
NT
0
0
0
1
0
NT
0
NT
0
0
0
0
0
0
0
NT
1
No.
Well
(A)
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1988
No.
Sam
Takn
Anlz
(B)
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
24
No.
Sam
Dets
(C)
0
0
0
0
0
0
0
0
0
0
1
0
0
0
0
0
0
0
0
0
0
0
0
0
1
No.
Dets
Exc
HBT
(D)
0
0
0
NT
NT
NT
0
NT
0
0
0
NT
0
NT
0
NT
0
0
0
0
0
0
0
NT
0
No.
Well
(A)
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1989
No.
Sam
Takn
Anlz
(B)
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
24
No.
Sam
Dets
(C)
0
0
0
0
0
0
0
0
0
1
0
0
1
0
0
0
0
0
0
0
0
0
0
0
2
No.
Dets
Exc
HBT
(D)
0
0
0
NT
NT
NT
0
NT
0
0
0
NT
1
NT
0
NT
0
0
0
0
0
0
0
NT
1
Source: QWOATA Data Base, U.S. Geological Survey. Boise District
(1) Health Based Threshold (HBT) is based on Final Federal MCL
(2) HBT is based on Proposed Federal MCL
(3) HBT is based on Federal Ambient Water Quality Criteria
NT No HBT Available
(A) Number of Wells
(B) Number of Samples Taken and Analyzed
(C) Number of Sample Detections
(D) Number of Detections that Exceed the HBT
-------
APPENDIX E: SUMMARY OF NITRATE DETECTIONS FOR
SELECTED COUNTIES IN IDAHO
-------
Table E-1: Nitrate Detections for Selected Counties in Idaho, U.S. Geological Survey
COUNTY
ADA
BUTTE
CANYON
CASSIA
JEFFERSON
KOOTENAI
MINIDOKA
TOTALS
1980
No.
Well
(A)
1
0
0
0
0
0
0
1
No.
Sam
Takn
Anlz
(B)
1
0
0
0
0
0
0
1
No.
Sam
Dets
(C)
1
0
0
0
0
0
0
1
No.
Dets
Exc
Fed.
MCL
(D)
0
0
0
0
0
0
0
0
1981
No.
Well
(A)
49
33
31
2
1
0
0
116
No.
Sam
Takn
Anlz
(B)
50
35
31
2
1
0
0
119
No.
Sam
Dets
(C)
48
34
28
2
1
0
0
113
No.
Dets
Exc
Fed.
MCL
(D)
0
6
0
0
0
0
0
6
1982
No.
Well
(A)
1
0
0
8
0
0
0
9
No.
Sam
Takn
Anlz
(B)
1
0
0
8
0
0
0
9
No.
Sam
Dets
(C)
0
0
0
5
0
0
0
5
No.
Dets
Exc
Fed.
MCL
(D)
0
0
0
0
0
0
0
0
1983
No.
Well
(A)
0
4
0
0
0
0
0
4
No.
Sam
Takn
Anlz
(B)
0
4
0
0
0
0
0
4
No.
Sam
Dets
(C)
0
4
0
0
0
0
0
4
No.
Dets
Exc
Fed.
MCL
(D)
0
0
0
0
0
0
0
0
1984
No.
Well
(A)
0
105
1
1
13
0
0
120
No.
Sam
Takn
Anlz
(B)
0
116
1
1
16
0
0
134
No.
Sam
Dets
(C)
0
111
1
1
14
0
0
127
No.
Dets
Exc
Fed.
MCL
(D)
0
1
0
0
0
0
0
1
COUNTY
ADA
BUTTE
CANYON
CASSIA
JEFFERSON
KOOTENAI
MINIDOKA
TOTALS
1985
No.
Well
(A)
0
5
0
22
0
0
0
27
No.
Sam
Takn
Anlz
(B)
0
5
0
22
0
0
0
27
No.
Sam
Dets
(C)
0
5
0
21
0
0
0
26
No.
Dets
Exc
Fed.
MCL
(D)
0
0
0
0
0
0
0
0
1986
No.
Well
(A)
0
7
0
16
0
0
0
23
No.
Sam
Takn
Anlz
(B)
0
10
0
16
0
0
0
26
No.
Sam
Dets
(C)
0
10
0
16
0
0
0
26
No.
Dets
Exc
Fed.
MCL
(D)
0
0
0
1
0
0
0
1
1987
No.
Well
(A)
0
1
0
75
0
0
24
100
No.
Sam
Takn
Anlz
(B)
0
1
0
112
0
0
25
138
No.
Sam
Dets
(C)
0
1
0
110
0
0
25
136
No.
Dets
Exc
Fed.
MCL
(D)
0
0
0
23
0
0
10
33
1988
No.
Well
(A)
19
63
0
18
0
11
0
111
No.
Sam
Takn
Anlz
(B)
24
67
0
18
0
11
0
120
No.
Sam
Dets
(C)
3
65
0
18
0
11
0
97
No.
Dets
Exc
Fed.
MCL
(D)
0
1
0
6
0
0
0
7
1989
No.
Well
(A)
0
71
0
0
8
0
1
80
No.
Sam
Takn
Anlz
(B)
0
92
0
0
9
0
1
102
No.
Sam
Dets
(C)
0
87
0
0
9
0
1
97
No.
Dets
Exc
Fed.
MCL
(D)
0
1
0
0
0
0
0
1
MCL: 10.0 mg/L
Source: QWDATA Data Base, U.S. Geological Survey, Boise District
(A) Number ol Wells
(B) Number of Samples Taken and Analyzed
(C) Number of Sample Detections
(D) Number of Detections that Exceed the Federal MCL
m
-------
Table E-2.1: Nitrate Detections for Selected Counties in Idaho, U.S. Forest Service (1980-1984)
COUNTY
ADA
ADAMS
BANNOCK
BEAR LAKE
BLAINE
BOISE
BONNEVILLE
BUTTE
CARIBOU
CASSIA
CLARK
CUSTER
ELMORE
FRANKLIN
FREMONT
GEM
IDAHO
JEFFERSON
LEMHI
MADISON
TETON
TWIN FALLS
VALLEY
WASHINGTON
TOTALS
1980
No.
Well
(A)
1
5
0
0
0
9
2
0
2
0
0
0
1
0
1
1
1
0
1
0
0
0
14
2
40
No.
Sam
Takn
Anlz
(B)
1
5
0
0
0
9
2
0
2
0
0
0
1
0
1
1
1
0
1
0
0
0
14
2
40
No.
Sam
Dets
(C)
1
5
0
0
0
9
2
0
2
0
0
0
1
0
1
1
1
0
1
0
0
0
14
2
40
No.
Dets
Exc
Fed.
MCL
(D)
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1981
No.
Well
(A)
0
3
0
0
0
5
1
1
1
0
0
17
1
0
1
0
3
0
23
0
0
0
9
2
67
No.
Sam
Takn
Anlz
(B)
0
3
0
0
0
6
1
1
1
0
0
18
1
0
1
0
3
0
23
0
0
0
9
2
69
No.
Sam
Dets
(C)
0
3
0
0
0
6
1
1
1
0
0
18
1
0
1
0
3
0
23
0
0
0
9
2
69
No.
Dets
Exc
Fed.
MCL
(D)
0
0
0
0
0
0
0
0
0
0
0
1
0
0
0
0
0
0
0
0
0
0
0
0
1
1982
No.
Well
(A)
0
1
0
0
0
2
3
0
0
0
0
4
0
0
1
0
2
0
1
0
0
0
2
0
16
No.
Sam
Takn
Anlz
(B)
0
1
0
0
0
2
3
0
0
0
0
5
0
0
1
0
2
0
1
0
0
0
2
0
17
No.
Sam
Dets
(C)
0
1
0
0
0
2
3
0
0
0
0
5
0
0
1
0
2
0
1
0
0
0
2
0
17
No.
Dets
Exc
Fed.
MCL
(D)
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1983
No.
Well
(A)
0
5
0
0
0
8
0
0
0
0
0
14
5
0
0
7
1
0
6
0
0
0
10
2
58
No.
Sam
Takn
Anlz
(B)
0
5
0
0
0
8
0
0
0
0
0
16
5
0
0
7
1
0
6
0
0
0
10
2
60
No.
Sam
Dets
(C)
0
5
0
0
0
8
0
0
0
0
0
16
5
0
0
7
1
0
6
0
0
0
10
2
60
No.
Dets
Exc
Fed.
MCL
(D)
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1984
No.
Well
(A)
1
4
0
0
1
2
4
1
0
2
0
27
1
0
0
0
3
0
22
0
1
4
4
4
81
No.
Sam
Takn
Anlz
(B)
1
4
0
0
1
3
4
1
0
2
0
27
1
0
0
0
3
0
22
0
1
4
4
4
82
No.
Sam
Dets
(C)
1
4
0
0
1
3
4
1
0
2
0
27
1
0
0
0
3
0
22
0
1
4
4
4
82
No.
Dets
Exc
Fed.
MCL
(D)
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
m
MCL: 10.0 mg/l
Source: U. S. Forest Service
(A) Number of Wells
(B) Number of Samples Taken and Analyzed
(C) Number of Sample Detections
(D) Number of Detections that Exceed the Federal MCL
-------
Table E-2.2: Nitrate Detections for Selected Counties in Idaho, U.S. Forest Service (1985-1989)
COUNTY
ADA
ADAMS
BANNOCK
BEAR LAKE
BLAINE
BOISE
BONNEVILLE
BUTTE
CARIBOU
CASSIA
CLARK
CUSTER
ELMORE
FRANKLIN
FREMONT
GEM
IDAHO
JEFFERSON
LEMHI
MADISON
TETON
TWIN FALLS
VALLEY
WASHINGTON
TOTALS
1985
No.
Well
(A)
0
5
3
8
2
1
2
0
8
2
0
12
0
3
0
0
3
0
4
0
0
0
4
2
59
No.
Sam
Takn
Anlz
(B)
0
5
3
8
2
1
2
0
9
2
0
12
0
3
0
0
3
0
4
0
0
0
4
2
60
No.
Sam
Dels
(C)
0
5
3
8
2
1
2
0
9
2
0
12
0
3
0
0
3
0
4
0
0
0
4
2
60
No.
Deis
Exc
Fed.
MCL
(D)
0
0
0
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
1986
No.
Well
(A)
0
5
0
0
0
2
5
0
0
0
4
14
0
0
11
0
0
1
10
0
1
0
4
2
59
No.
Sam
Takn
Anlz
(B)
0
6
0
0
0
2
5
0
0
0
4
14
0
0
12
0
0
1
11
0
1
0
4
3
63
No.
Sam
Dets
(C)
0
6
0
0
0
2
5
0
0
0
4
14
0
0
12
0
0
1
11
0
1
0
4
3
63
No.
Dels
Exc
Fed.
MCL
(D)
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1987
No.
Well
(A)
1
4
0
0
0
3
0
1
0
1
0
12
0
0
0
0
3
0
21
0
0
0
2
2
50
No.
Sam
Takn
Anlz
(B)
1
4
0
0
0
3
0
1
0
1
0
12
0
0
0
0
3
0
21
0
0
0
2
2
50
No.
Sam
Dets
(C)
1
4
0
0
0
3
0
1
0
1
0
12
0
0
0
0
3
0
21
0
0
0
2
2
50
No.
Dets
Exc
Fed.
MCL
(D)
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1988
No.
Well
(A)
0
3
0
0
0
1
0
0
0
0
0
8
0
0
2
0
3
0
3
0
0
0
2
1
23
No.
Sam
Takn
Anlz
(B)
0
3
0
0
0
1
0
0
0
0
0
8
0
0
2
0
3
0
3
0
0
0
2
1
23
NO.
Sam
Dets
(C)
0
3
0
0
0
1
0
0
0
0
0
8
0
0
2
0
3
0
3
0
0
0
2
1
23
No.
Dets
Exc
Fed.
MCL
(D)
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1989
No.
Well
(A)
0
4
1
0
0
1
11
0
1
0
3
0
0
0
13
0
0
1
7
1
2
0
4
1
50
No.
Sam
Takn
Anlz
(B)
0
4
1
0
0
1
11
0
1
0
3
0
0
0
13
0
0
1
7
1
2
0
4
1
50
No.
Sam
Dets
(C)
0
4
1
0
0
1
11
0
1
0
3
0
0
0
13
0
0
1
7
1
2
0
4
1
50
No.
Dets
Exc
Fed.
MCL
(D)
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
m
MCL: 10.0mg/l
Source: U. S. Forest Service
(A) Number of Wells
(B) Number of Samples Taken and Analyzed
(C) Number of Sample Detections
(D) Number of Detections that Exceed the Federal MCL
-------
Table E-3: Nitrate Detections for Kootenai County, Idaho, Water Quality Bureau
COUNTY
KOOTENAI
1980
No.
Well
(A)
6
No.
Sam
Takn
Anlz
(B)
6
No.
Sam
Dels
(C)
6
No.
Dels
Exc
Fed.
MCL
(D)
0
1981
No.
Well
(A)
7
No.
Sam
Takn
Anlz
(B)
28
No.
Sam
Dets
(C)
28
No.
Dets
Exc
Fed.
MCL
(D)
0
1982
No.
Well
(A)
8
No.
Sam
Takn
Anlz
(B)
16
No.
Sam
Dets
(C)
16
No.
Dets
Exc
Fed.
MCL
(D)
0
1983
No.
Well
(A)
8
No.
Sam
Takn
Anlz
(B)
33
No.
Sam
Dets
(C)
33
No.
Dets
Exc
Fed.
MCL
(D)
0
1984
No.
Well
(A)
8
No.
Sam
Takri
Anlz
(B)
17
No.
Sam
Dets
(C)
17
No.
Dets
Exc
Fed.
MCL
(D)
0
COUNTY
KOOTENAI
1985
No.
Well
(A)
8
No.
Sam
Takn
Anlz
(B)
30
No.
Sam
Dets
(C)
30
No.
Dels
Exc
Fed.
MCL
(D)
0
1986
No.
Well
(A)
9
No.
Sam
Takn
Anlz
(B)
30
No.
Sam
Dets
(C)
30
No.
Dets
Exc
Fed.
MCL
(D)
0
1987
No.
Well
(A)
9
No.
Sam
Takr
Anlz
(B)
28
No.
Sam
Dets
(C)
28
No.
Dets
Exc
Fed.
MCL
(D)
0
1988
No.
Well
(A)
9
No.
Sam
Takn
Anlz
(B)
28
No.
Sam
Dets
(C)
28
No.
Dets
Exc
Fed.
MCL
(D)
0
1989
NO.
Well
(A)
9
No.
Sam
Takn
Anlz
(B)
23
No.
Sam
Dets
(C)
23
No.
Dets
Exc
Fed.
MCL
(D)
0
m
01
MCL: 100mg/l
Source: Water Quality Bureau's Rathdrum Prairie Data Base
(A) Number of Wells
(B) Number of Samples Taken and Analyzed
(C) Number of Sample Detections
(O) Number of Detections that Exceed the Federal MCL
-------
APPENDIX F: SUMMARY OF AGENCIES THAT TRACK INDICATOR
DATA IN IDAHO
-------
F-2
The following table outlines the State agencies that track indicator data and describes the
relevant data bases and types of data collected. In several cases, more than one agency or
organization tracks relevant information. Indicator data management for each data base is discussed
in greater detail in Section III of this study.
Indicator Responsible Agency
MCLs Idaho Department of Health
and Welfare, Division of
Environmental Quality, Water
Quality Bureau
U.S. EPA, Office of Drinking
Water
Hazardous Idaho Department of Health
Waste Sites and Welfare, Division of
Environmental Quality,
Hazardous Materials Branch
Data Base/Type of Information
WQB tracks MCL compliance reports for 3200 public drinking
water systems. Data are currently on Macintosh PCs but are
being transferred to IBM PCs. Data are also entered into the
FRDS system.
EPA maintains the Federal Reporting Data System (FRDS-II)
which serves as the national data base for tracking MCL
compliance data provided by States.
HMB has limited ground-water quality data for Idaho's seven
RCRA Subtitle C facilities. Date for all but one site are in hard
copy format only. No data are available for Idaho's six
CERCLA sites, but may be available from EPA Region X.
VOCs
Nitrate
Pesticides
U.S. EPA, Region X, Office of
Ground Water
USGS, Boise District
Idaho Water Quality Bureau
USGS, Boise District
U.S. Forest Service,
Intermountain Region
U.S. Forest Service, Northern
Region
Idaho Water Quality Bureau
None
EPA Region X has ground-water contamination data in hard
copy files for Idaho's six CERCLA sites.
USGS, Boise District has collected data including analytical
results for VOCs from well sites it maintains including wells at
the INEL and Mountain Home Air Force Base sites. These
data are maintained in the District's QWDATA data base.
WQB has collected data from 40-50 UST remedial responses
in hard copy format. An additional data base covering 8,000-
10,000 USTs is also maintained by WQB but does not contain
ground-water monitoring information.
USGS, Boise District collects ground-water quality data
including nitrates from approximately 3,900 wells throughout
the State. These data are maintained in the District's QWDATA
data base.
USFS, Intermountain Region maintains .an automated data
base on campground water quality. The data base includes
several elements including analytical results for nitrate, lead,
fluorides, and several other inorganic chemicals.
USFS, Northern Region maintains a data set on campground
water quality. Data set consists of hard copy laboratory
analyses for several ground-water contaminants.
Coeur d'Alene Office maintains data base on monitoring results
of the Rathdrum Prairie aquifer. WQB maintains this data base
in a Lotus spreadsheet.
There is currently no data management pertaining to pesticide
use or purchase on a State-wide or Regional basis in Idaho.
-------
APPENDIX G: ENVIRONMENTAL INDICATOR QUESTIONNAIRE
-------
G-2
Appendix G - Environmental Indicator Questionnaire
DATE:
SITE ID #:
SITE NAME:
SITE LOCATION:
STATE:
COUNTY:
LATITUDE:
LONGITUDE:
GROUND WATER
CONTAMINANTS
PCB's:
PESTICIDES:
OTHER ORGANICS:
METALS:
CONVENTIONAL:
BACTERIA:
PROGRAM:
RCRA
CERCLA
OTHER:
CONCENTRATION
LEVEL STATUS
Enter the following values for
concentrations:
0 - unknown
1 - at or below detection limit
2 - above detection limit
3 - above level of concern
HAS THE PLUME BEEN DETECTED OFF-SITE?:
POPULATION POTENTIALLY AT RISK (3 mile radius)
IS CONTAMINATION REACHING DRINKING WATER WELLS?:
(y««/no/unknown)
(y»i/no/unknown)
ACTUAL POPULATION AFFECTED:
------- |