Toxic-Impaired Waterbodies on 303(d)
Lists in the Columbia River Basin
David Gruen, ORISE Participant
U.S. Environmental Protection Agency, Region 10
May 2020
-------
Acknowledgements
This project relied on contributions from many U.S. Environmental Protection Agency
employees. In particular, the author wishes to thank Mary Lou Soscia for championing efforts to
address toxics in the Columbia River Basin, for inspiring this project, and for her detailed review
and thoughtful suggestions. In addition, the following EPA staff deserve recognition for their
feedback and recommendations:
U.S. Environmental Protection Agency Region 8:
Peter Brumm
U.S. Environmental Protection Agency Region 10:
Keyyana Blount
Jill Fullagar
Lon Kissinger
James Lopez-Baird
Miranda Magdangal
Martin Merz
Michelle Wilcox
Toxic-Impaired Waterbodies on 303(d) Lists in the Columbia River Basin
1
-------
Table of Contents
Acknowledgements 1
Executive Summary 5
Purpose 7
Background 7
Data Sources 9
Overview of Impaired Waters 10
Metals/Inorganics 14
Arsenic 14
Copper 15
Lead 17
Mercury 19
Selenium 21
Pesticides 23
Aldrin/Dieldrin 23
Chlorpyrifos 24
Dichlorodiphenyltrichloroethane (DDT) 26
Persistent Organic Pollutants 27
Polycyclic Aromatic Hydrocarbons (PAHs) 27
Polychlorinated Biphenyls (PCBs) 29
Total Maximum Daily Loads for Toxic Contaminants 31
Idaho 32
Oregon 40
Washington 41
Columbia River Basin TMDLs 44
Appendix A. Category 5 Toxics-Impaired Waters in Western Montana 45
Appendix B. Toxics TMDLs in the Columbia River Basin 46
Works Cited 48
Toxic-Impaired Waterbodies on 303(d) Lists in the Columbia River Basin 2
-------
List of Figures
Figure 1. Category 5 toxics-impaired waters in the Columbia River Basin 12
Figure 2. EPA-approvedTMDLs for toxic pollutants in the Columbia River Basin 13
Figure 3. Arsenic impaired waterbodies in the Columbia River Basin 14
Figure 4. Copper impaired waters in the Columbia River Basin 16
Figure 5. Lead impaired waters in the Columbia River Basin 18
Figure 6. Mercury impaired waters in the Columbia River Basin 20
Figure 7. Selenium impaired waters in the Columbia River Basin 22
Figure 8. Aldrin and/or Dieldrin impaired waters in the Columbia River Basin 23
Figure 9. Chlorpyrifos impaired waters in the Columbia River Basin 25
Figure 10. DDT impaired waters in the Columbia River Basin 26
Figure 11. PAH impaired waters in the Columbia River Basin 28
Figure 12. PCB impaired waters in the Columbia River Basin 30
Figure 13. Toxics-impaired waters (both categories 4a and 5) and abandoned mines in western Montana 45
Table 1. Data sources 9
Table 2. Toxic pollutants on 303(d) lists in the Columbia River Basin 10
Table 3. Watersheds with arsenic impaired waters 15
Table 4. Watersheds with copper impaired waters 17
Table 5. Watersheds with lead impaired waters 19
Table 6. Watersheds with mercury impaired waters 21
Table 7. Watersheds with selenium impaired waters 22
Table 8. Watersheds with Aldrin and/or Dieldrin impaired waters 24
Table 9. Watersheds with Chlorpyrifos impaired waters 25
Table 10. Watersheds with DDT impaired waters 27
Table 11. Watersheds with waters impaired by PAHs 28
Table 12. Watersheds with waters impaired by PCBs 31
Table 13. Toxic pollutants with approvedTMDLs in the Lower Clark Fork River watershed 32
Table 14. Toxic pollutants with approvedTMDLs in the Snake River- Hells Canyon watershed 32
Table 15. Toxic pollutants with approvedTMDLs in the Upper Coeur d'Alene River watershed 33
Table 16. Toxic pollutants with approvedTMDLs in the Upper Snake River watershed 33
Table 17. Toxic pollutants with approvedTMDLs in the Bitterroot River watershed 33
Table 18. Toxic pollutants with approvedTMDLs in the Blackfoot Headwaters planning area 34
Table 19. Toxic pollutants with approvedTMDLs in the Clark Fork — Drummond planning area 34
Table 20. Toxic pollutants with approved TMDLs in the Clark Fork and Silver Bow Creek planning area 35
Table 21. Toxic pollutants with approvedTMDLs in the Flint Creek watershed 35
Table 22. Toxic pollutants with approvedTMDLs in the Kootenai - Fisher Project Area 36
Table 23. Toxic pollutants with approvedTMDLs in the Little Blackfoot planning area 36
Table 24. Toxic pollutants with approvedTMDLs in the Middle Blackfoot-Nevada Creek planning area 37
Table 25. Toxic pollutants with approvedTMDLs in the Ninemile planning area 37
Table 26. Toxic pollutants with approvedTMDLs in the Prospect Creek planning area 38
Table 27. Toxic pollutants with approvedTMDLs in the Rock Creek planning area 38
Table 28. Toxic pollutants with approvedTMDLs in the Thompson Project planning area 39
Table 29. Toxic pollutants with approvedTMDLs in the Upper Clark Fork planning area 39
Table 30. Toxic pollutants with approvedTMDLs in the Snake River - Hells Canyon watershed 40
Table 31. Toxic pollutants with approvedTMDLs in the Willamette River watershed 40
Table 32. Toxic pollutants with approvedTMDLs in the Lake Chelan watershed 41
Table 33. Toxic pollutants with approvedTMDLs in the Lower Okanogan River watershed 42
Table 34. Toxic pollutants with approvedTMDLs in the Palouse River watershed 42
Toxic-Impaired Waterbodies on 303(d) Lists in the Columbia River Basin
3
-------
Table 35. Toxic pollutants with approvedTMDLs in the Spokane River watershed 43
Table 36. Toxic pollutants with approvedTMDLs in the Walla Walla River watershed 43
Table 37. Toxic pollutants with approvedTMDLs in the Wenatchee River watershed 43
Table 38. Toxic pollutants with approvedTMDLs in the Yakima River watershed 44
Table 39. Toxics TMDLs in the Columbia River Basin 46
Toxic-Impaired Waterbodies on 303(d) Lists in the Columbia River Basin 4
-------
Executive Summary
Under the Clean Water Act (CWA), states are required to assess their waters biennially and identify
waterbodies that fail to meet their designated uses due to impaired water quality conditions on the
[CWA Section] 303(d) list. This report focuses on two categories of toxic-impaired waterbodies on 303(d)
lists: category 4a and category 5 waters. Category 4a waters have been identified as impaired and have
an EPA-approved Total Maximum Daily Load (TMDL) that sets out a pollution budget. Category 5 waters
are impaired and require a TMDL or water pollution control plan.
Recognizing how difficult it was to develop TMDLs to address toxics, in 2005 the U.S. Environmental
Protection Agency (EPA) established the Columbia River Toxics Reduction Working Group to share
information and coordinate actions to understand and reduce toxics. In 2016, Congress amended the
CWA, creating Section 123, the Columbia River Basin Restoration Act. Section 123 directed EPA to
establish the Columbia River Basin Restoration Working Group modeled after the existing Columbia
River Toxics Reduction Working Group and provided a framework for future funding of toxic reduction,
monitoring, and outreach actions through a competitive grant program.
This report is intended for use by the Columbia River Basin Restoration Working Group members and
other entities working to understand and reduce toxics in the Columbia River Basin (the Basin).
Waterbodies listed as impaired for toxic pollutants can serve as a starting point for prioritizing
restoration and management actions and the absence of waterbodies on 303(d) lists can help identify
data gaps to inform future monitoring and assessment efforts. This report:
1) identifies the more than 50 toxic contaminants that are on 303(d) lists of impaired waters in
the Columbia River Basin,
2) summarizes the location of impaired waters for ten toxic contaminants, and
3) provides links to EPA-approved TMDLs and implementation plans.
The ten contaminants featured in the report are:
arsenic
copper
lead
mercury
selenium
Aldrin/Dieldrin
Chlorpyrifos
Dichlorodiphenyltrichloroethane (DDT) and its breakdown products
polychlorinated biphenyls (PCBs)
polycyclic aromatic hydrocarbons (PAHs)
Toxics-impaired waters are broadly distributed throughout the Basin. The mainstem Columbia River is
impaired sporadically in Washington and nearly the entire reach from McNary Dam to the mouth of the
estuary is impaired for one or more toxic pollutants. The mainstem Snake River has multiple segments
with identified category 5 impairments, including the entire reach that forms the border between
Oregon and Idaho. In total, 31 TMDL documents that address at least one toxic pollutant have been
developed in the Basin. Every state has developed at least one TMDL for toxic pollutants: Idaho (5),
Montana (13), Oregon (4), Washington (9), and EPA developed a basin-wide Dioxin TMDL that covers the
lower mainstem Columbia River. Significant reaches of the upper Pend Oreille River watershed in
Toxic-Impaired Waterbodies on 303(d) Lists in the Columbia River Basin
5
-------
Montana and the Willamette River watershed in Oregon are covered by TMDLs for one or more toxic
pollutants.
Although states are not required under CWA Section 303(d) to develop TMDL implementation plans,
many states include a description of the actions that will be taken to achieve the pollutant load
reductions. EPA is not required to and does not approve TMDL implementation plans. For
organochlorine pesticides, implementation plans focus on strategies to keep contaminated sediment
from entering waterways using agricultural and urban best management practices. To address metals
contamination from legacy mining activities, implementation plans commonly recommend remediation
and restoration of mine and waste sites and additional source assessment monitoring.
Toxic-Impaired Waterbodies on 303(d) Lists in the Columbia River Basin
6
-------
Purpose
This document is intended for use by Columbia River Basin Restoration Program Working Group
members and other interested entities working to better understand and reduce toxics in the Basin. The
document 1) identifies the more than 50 toxic contaminants that are on Clean Water Act (CWA) 303(d)
lists of impaired waters in the Columbia River Basin, 2) summarizes the location of toxics-impaired
waters for ten contaminants regulated under the Clean Water Act, and 3) provides links to the EPA-
approved TMDLs that calculate pollution budgets for toxic pollutants and implementation plans that
specify how to attain required pollutant load reductions.
Background
Toxic contaminants are naturally occurring or manufactured chemicals that can be harmful to fish,
wildlife, and people. Many toxic contaminants break down slowly and can accumulate in the
environment and concentrate in plants, wildlife, and people through bioaccumulation/magnification1.
For the purposes of this document, toxic contaminants are defined as metals, pesticides and their
breakdown products, and/or organic or inorganic compounds that are known to negatively affect the
health of fish, wildlife, and human health. Conventional pollutants, such as temperature, total
nitrogen/phosphorus, and bacteria, among others, are not considered toxic contaminants and are
excluded from the analysis.
Although many data gaps remain, monitoring and assessment of toxic contamination in the Basin has
increased over the last several decades. In the early 1990s, EPA published the National Study on
Chemical Residues in Fish which found toxic contaminants were present in fish tissues in the Basin at
elevated levels that could negatively impact aquatic life and human health (EPA, 1992). In 2002, EPA
released the Columbia River Basin Fish Contaminant Survey: 1996-1998 which analyzed concentrations
of 132 chemicals in the tissues of anadromous and resident fish species collected at 24 locations
throughout the Basin. All species of fish had some levels of toxic chemicals in their tissues. Of the
chemicals analyzed, a breakdown product of DDT, PCBs, zinc, and aluminum were detected in the
highest concentrations in most of the fish tissues (EPA, 2002). In 1997-1998, researchers from the U.S.
Geological Survey collected and analyzed over 500 fish, predominately common carp, black bass, and
largescale sucker, from 16 sites in the Basin. Concentrations of lead in the upper Columbia River,
selenium in the lower and middle Columbia River, and mercury throughout the basin exceeded one or
more wildlife criteria in composite fish samples (Hinck et al., 2004). EPA has published a reference
document featuring peer reviewed science and federal, state, and tribal government reports and
publications related to toxic pollutants in the aquatic environment on its Columbia River website.
Fish and fisheries used by Columbia River Tribes are part of tribal culture, spirituality, nutrition, and
economics. It has been documented that tribal members historically consumed much higher amounts of
fish (Harper & Walker, 2015). As a result, Native Americans (and other high fish-consuming populations)
are at much higher risk due to exposure to contaminants in fish. The Columbia River Inter-Tribal Fish
Commission (1994) published a fish consumption survey of its member tribes that found, on average,
adult tribal members consumed 58.7 grams of fish per day, 9 times the fish consumption rate of 6.5
grams per day used by EPA to establish water quality criteria at the time. A more recent fish
consumption survey of Idaho tribes has corroborated these results. In recognition of this, Oregon and
1 Bioaccumulation refers to the accumulation of a toxic chemical in the tissue of a particular organism;
biomagnification refers to the increased concentration of a toxic chemical the higher an animal is on the food
chain.
Toxic-Impaired Waterbodies on 303(d) Lists in the Columbia River Basin
7
-------
Washington have used fish consumption rates of 175 grams per day, approximately the 95th percentile
fish consumption rates from the Columbia River Inter-Tribal Fish Commission (1994) survey to establish
state water quality criteria. Tribes would like to increase their fish consumption and at the same time,
avoid unacceptable health risks. This can only be done by reducing toxic contaminant levels in the
Columbia River and its tributaries.
In 2005, EPA established the Columbia River Toxics Reduction Working Group, a voluntary collaboration
between tribal, state, and local governments; federal agencies; industry; soil and water conservation
districts; and nonprofit organizations. The group was created to share information, coordinate activities,
and develop actions to assess and reduce toxics in the Basin. There was a recognition that this work was
needed due to the difficulty in developing Total Maximum Daily Loads and implementation plans for
toxic pollutants, many of which had unknown sources and unknown actions to reduce those pollutants.
The Working Group summarized available information on four priority indicator chemicals in the 2009
State of the River Report for Toxics and identified 61 actions to reduce toxic pollutants the 2010
Columbia River Toxics Reduction Action Plan.
In 2016, Congress amended the Clean Water Act by adding Section 123 which required EPA to establish
the Columbia River Basin Restoration Program. It was the first legislation to officially designate the
national importance of restoring the Basin. Clean Water Act Section 123 directed EPA to establish the
Columbia River Basin Restoration Program Working Group modeled after the Columbia River Toxics
Reduction Working Group and provided a framework for future funding of toxic reduction, monitoring,
and outreach actions. In fiscal year 2019, Congress appropriated $1 million to EPA to implement the
program and in provided $1.2 million for 2020.
There are over 86,000 chemicals registered for use in commerce in the United States (EPA, 2019i). Only
a small number, however, are regulated under the Clean Water Act (CWA), the primary law regulating
pollution of the nation's waterways. While not comprehensive, two lists, the Toxic Pollutant List and the
Priority Pollutant List, were developed in the mid-1970's to help states and EPA address toxics chemicals
through effluent limits, permits, and water quality criteria (either numeric or narrative). The Toxic
Pollutant List specifies 65 pollutants or groups of pollutants and is referenced by the CWA at Section
307(a)(1). The Priority Pollutant List builds off the Toxic Pollutant List by specifying 126 specific
pollutants that were produced in significant quantities, found in the nation's waterways at a frequency
occurrence of at least 2.5 percent, and had published analytical test methods (EPA, 2019a).
Section 305(b) of the CWA requires states to assess the quality of their waters every two years and
submit a report to the EPA on the condition of their surface waterbodies. The statewide assessment
information is referred to as the "[CWA Section] 305(b) list". Waterbodies are classified into one of five
categories ranging from category 1 (meets water quality standards) to category 5 (polluted waters that
require a pollution control measure). Waterbodies that fail to meet numeric and/or narrative water
quality criteria established to achieve their designated use(s) are considered "impaired" under the CWA.
Impaired waterbodies are cataloged in a list, referred to as the "[CWA Section] 303(d) list."
This report focuses on two categories of toxic(s)-impaired waterbodies on 303(d) lists: category 4a and
category 5 waters. Category 4a waters have been identified as impaired and have an EPA-approved
TMDL that sets out a pollution budget, including allocations for point and nonpoint sources of pollution.
The waterbody remains on the 303(d) list until the implementation actions achieve the pollutant load
reductions identified in the TMDL and the water quality meets applicable water quality criteria. The
report also identifies category 5 waters. Category 5 waters are impaired and require a water quality
Toxic-Impaired Waterbodies on 303(d) Lists in the Columbia River Basin
8
-------
improvement project. Under the CWA, states are required to establish TMDLs for the pollutant(s) that
cause the category 5 impairments.
This document provides information on known toxics-impaired waterbodies which may be helpful for
prioritizing monitoring and reduction actions. In addition to identifying all toxic contaminants on 303(d)
lists and TMDLs that have been developed for toxics in the Basin, the report summarizes the location of
waterbodies impaired by ten metals and inorganic compounds, pesticides, and persistent organic
pollutants:
Metals/Inorganics:
1. Arsenic
2. Copper
3. Lead
4. Mercury
.5. Selenium
Pesticides:
6. Aldrin/Dieldrin
7. Chlorpyrifos
8. DDT (and its breakdown
products)
Persistent Organic
Pollutants:
9. PCBs
10. PAHs
Data Sources
The States of Idaho, Montana, Oregon, and Washington publish Integrated Reports that contain their
305(b) and 303(d) lists, including the geographic data specifying the location and extent of the river/lake
reaches and the cause of the impairment, among other information. For the purpose of this report, the
data used to create the tables, maps, and description of the location of impaired waterbodies were
downloaded directly from each state's database (Table 1). For Idaho, Montana, and Washington, the
report uses the most recent EPA-approved Integrated Report data. For Oregon, the memo relies on the
state's final 2018/2020 Integrated Report submitted to EPA in April 2020 for review and approval. As of
May 2020, EPA had not approved the new Integrated Report. Until the new Integrated Report is
approved by EPA, Oregon's 2012 Integrated Report remains in effect for CWA purposes.
Table 1. Data sources.
State
Assessment
Document
Date of EPA
Data Source
Cycle
Status
Approval
Idaho
2016
Final
June 2019
https://opengisdata-
idahodea.ODendata.arcgis.com/datas
ets/idaho-deq-2016-final-
%C2%A7305b-%C2%A7303d-
integrated-report-rivers-streams-
lakes-reservoirs
Montana
2018
Final
February
2019
https://svc.mt.gOv/deq/dst/#/app/c
waic
Oregon
2018/2020
Submitted to
EPA for
approval
N/A
https://www.oregon.gov/deq/wq/Pa
ges/2018-lntegrated-Report.aspx
Washington
2012
Final
July 2016
http://geo.wa.gov/datasets/waecv::
waecv-water-qualitv-assessment-
305b-report-current
Toxic-Impaired Waterbodies on 303(d) Lists in the Columbia River Basin
9
-------
Overview of Impaired Waters
More than 50 toxic pollutants have been identified as causing category 4a or 5 impairments to surface
waterbodies in the Basin (Table 2). Five contaminants impair surface waterbodies within the Basin in
each of the four states - arsenic, copper, lead, mercury, and zinc. DDT and its breakdown products,
cadmium, Chlorpyrifos, and PCBs have been identified as causing impairments within three states.
The absence of waters identified as impaired for a pollutant is not inherently indicative of better water
quality and may be due to a lack of credible monitoring or assessment data available to the state.
Conversely, waterbodies that were listed as impaired by non-persistent toxics that have since been
banned or voluntarily phased out, may not currently have measurable concentrations that exceed water
quality standards. For example, the Oregon Department of Environmental Quality has not detected the
insecticides Guthion (azinphos-methyl), Parathion and Methyl Parathion in Oregon waters by since 2013
even though pesticide monitoring has expanded over the past 6 years (K. Masterson2, personal
communication, March 24, 2020). Similarly, there have been no detections of those insecticides by the
Idaho State Department of Agriculture in Idaho waters since 2010 (K. Masterson, personal
communication, May 7, 2020).
Direct comparisons between the states or between watersheds in the same state can be difficult. States
have different water quality standards and different methodologies for determining the size of impaired
reaches. Impairments can differ markedly in total area (e.g. stream miles or acres of lakes). A greater
number of impairments may not necessarily translate into a larger overall area of impaired water. For
additional information, including the location and extent of specific impaired waterbodies for each
pollutant, refer to each state's respective Integrated Report data referenced in Table 1.
Table 2. Toxic pollutants on 303(d) lists in the Columbia River Basin.
Toxic Contaminant
2,3,7,8-TCDD (Dioxir
2,3,7,8-TCDD TEQ
4,4'-DDD
4,4'-DDE
4,4'-DDT
Aldrin/Dieldrin
Alpha-BHC
Aluminum
Antimony
Arsenic
Benz(a)anthracene [PAH]
Benzo(a)pyrene [PAH]
Benzo(b)fluoranthene 3,4 [PAH]
Benzo(k)fluoranthene [PAH]
Beryllium
Cadmium
Chlordane
Chlorine
Chlorpyrifos
State(s)
OregonjJ/Vashingtc
Washington
Idaho, Oregon, Washington
Idaho, Oregon, Washington
Idaho, Oregon, Washington
Idaho, Oregon, Washington
Washington
Montana
Idaho, Montana
Idaho, Montana, Oregon, Washington
Oregon
Oregon
Oregon
Oregon
Montana
Idaho, Montana, Washington
Washington
Idaho, Oregon, Washington
! Toxics Coordinator, Oregon Department of Environmental Quality
Toxic-Impaired Waterbodies on 303(d) Lists in the Columbia River Basin
10
-------
Oregon
Oregon
Toxic Contaminant
Chromium VI
Chrysene
Copper
Cyanide .
Diazinon
Endosulfan
Endosulfan Sulfate
Endrin Aldehyde
Ethylbenzene
Ethylhexyl Phthalate bis 2
Guthion
Heptachlor
Heptachlor Epoxide
Hexachlorobenzene
lndeno(l,2,3-cd)pyrene
Iron
Lead
Malathion
Manganese
Mercury
Methyl Parathion
Methylmercury
Oil and Grease
Parathion
Polychlorinated Biphenyls (PCBs)
Polycydic Aromatic Hydrocarbons (PAHs)
Selenium
Sulfate
Silver
Tetrachloroethylene
Thallium
Toxaphene
| Trichloroethylene
Note: The names of toxic contaminants have been
303(d) lists. Text in brackets was added to identify
State(s)
Oregon
Oregon
Idaho, Montana, Oregon, Washington
Montana, Oregon
Oregon
Oregon
Oregon
Oregon
Oregon, Washington
Oregon, Washington
Oregon
Montana, Oregon
Idaho, Montana, Oregon, Washington
Idaho, Oregon
Montana
Idaho, Montana, Washington, Oregon
Idaho
Oregon
Idaho, Montana
Oregon
Montana, Oregon, Washington
Oregon
Idaho, Montana
Montana
Oregon, Washington
Oregon
Oregon
Washington
Oregon
'..'..'..'..'..'..'.yldaHo, Oregon, Montana, W<=
standardized and may be represented differently on state
specific PAH compounds.
Category 5 impairments for toxics are broadly distributed throughout the Basin (Figure 1). Segments of
the mainstem Columbia River are impaired sporadically through Washington State including the
segments above the mouth of the Chelan River, above and below the Wenatchee River confluence, and
the stretch of the river within the Hanford Reach National Monument. Nearly the entire length of the
mainstem Columbia River from McNary Dam to the estuary is impaired for one or more toxic pollutants.
Category 5 impairments cover significant portions of the mainstem Snake River as well. The Snake River
is impaired for one or more toxic contaminants between Idaho Falls and the American Falls Dam, the
entire reach that forms the Oregon and Idaho border, and in multiple segments between Lewiston, ID
Toxic-Impaired Waterbodies on 303(d) Lists in the Columbia River Basin
11
-------
and the confluence with the Columbia River near the Tri-Cities, WA3. Major tributary basins in Oregon
with category 5 toxic impairments include the Owyhee, Malheur, Umatilla and Willamette River
watersheds. In Idaho, major watersheds that have stream segments with one or more category 5 toxic
impairments include the Coeur d'Alene and Pend Oreille River watersheds. Major tributary basins in
Washington with toxics-related category 5 impairments include the Spokane River, Lake Chelan,
Wenatchee River, and Yakima Rivers. In Montana, Lake Koocanusa and Flathead Lake are listed as
category 5 for being impaired or threatened by at least one toxic pollutant.
I I Columbia R. Basin Boundary
Toxics Impaired Streams (Cat 5)
IB Toxics Impaired Lakes (Cat. 5)
I I Toxics Impaired Watersheds (Cat. 5)
120 160
£ OpenSraaWwp nxiticfltelC Cwwgtty
Mantes fan HERE.
Figure 1. Category 5 toxics-impaired waters in the Columbia River Basin. The map is not authoritative and should
be used for reference purposes only. The map is not to be used for legal purposes. Impaired waterbody segments
have been slightly enlarged to improve their visibility and are not to scale.
TMDLs have been developed for toxics in each of the four basin states, and several TMDLs cover
portions of one or more states. In 1992, EPA developed a basin wide TMDL for dioxins that covers
reaches of the mainstem Columbia River. Idaho and Oregon jointly issued a TMDL in 2004 for DDT and
its breakdown products and Dieldrin for the Hells-Canyon reach of the Snake River that forms the border
between the two states. Montana has developed 19 TMDLs in the Columbia River Basin portion of the
state to address contamination from legacy mining impacts, predominately in the Pend Oreille River
basin. Major tributary watersheds with at least one toxic(s) TMDL in Washington include the Lake
3 The Kennewick-Pasco-Richland metropolitan area
Toxic-Impaired Waterbodies on 303(d) Lists in the Columbia River Basin
12
-------
Chelan, and the Spokane, Similkameen, Yakima, and Walla Walla River basins. In Oregon, the
Willamette River watershed has multiple TMDLs for toxics.
<£ QpenSli wjtHn conftl
I I Columbia R. Basin Boundary
— Toxics TMDLs on Streams
H Toxics TMDLs on Lakes/ Reservoirs
I ) Toxics TMDLs In Watersheds
m ¦ Miles
0 20 40 80 120 160
CcrtwmrMy
Figure 2. EPA-approved TMDLs for toxic pollutants in the Columbia River Basin. The map is not authoritative and
should be used for reference purposes only. The map is not to be used for legal purposes. Impaired waterbody
segments have been slightly enlarged to improve their visibility and are not to scale.
The following section provides a description of ten toxic contaminants (or classes of contaminants),
identifies their major sources or pathways into the environment, and details the locations of impaired
waters listed under Category 4a or 5 on the mainstem Columbia and Snake Rivers and in tributary
watersheds.
Toxic-Impaired Waterbodies on 303(d) Lists in the Columbia River Basin
13
-------
Metals/Inorganics
Arsenic
Arsenic is a naturally occurring element found in the Earth's crust. Arsenic combined with oxygen,
chlorine and sulfur is considered inorganic arsenic; arsenic combined with carbon and hydrogen is
referred to as organic arsenic. Inorganic arsenic, long recognized as a human poison, is the form of
greatest concern and has been classified as a human carcinogen by the U.S. EPA's Integrated Risk
Information System (IRIS) in 1995 (EPA, 2017b). Natural sources of arsenic include volcanic activity and
weathering of arsenic-containing minerals and ores. Major anthropogenic sources of arsenic include
metal mining and smelting, pesticides, leaching from pressure-treated lumber, combustion of coal or
wood products, glass manufacturing, and waste incineration (EPA, 1998).
Ol)
-------
TMDLs, and arsenic impairs a stream in the Flathead Lake watershed4 that is not covered by a TMDL. The
South Fork Salmon, Upper Coeur d'Alene, and North and Middle Forks Boise River watersheds in Idaho
have at least one river reach impaired for arsenic. The Similkameen River watershed in Washington has
both a TMDL for arsenic and also includes one waterbody listed as impaired for inorganic arsenic,
Connors Lake, that is listed under category 5 and not covered by the TMDL.
Table 3. Watersheds with arsenic impaired waters.
State
Location of impaired waters without a TMDL
Location of EPA-approved TMDLs
(Category 5)
(Category 4a)
Idaho
South Fork Salmon, Upper Coeur d'Alene, and
North and Middle Forks Boise River watersheds
None
Montana
Flathead Lake watershed
Clark Fork - Drummond, Clark Fork
- Silver Bow Creek, Flint Creek,
Kootenai - Fisher Project, Little
Blackfoot River, Middle Blackfoot-
Nevada Creek, Prospect Creek
Oregon
Mainstem Columbia River;
Owyhee, Malheur, Powder, Burnt Umatilla,
Deschutes, and Willamette River watersheds
None
Washington Similkameen River watershed ^
[similkameen River watershed
Note: The Montana TMDLs are listed by the name of their respective planning areas.
Copper
Copper is an abundant trace metal commonly found in aquatic systems as a result of both natural and
anthropogenic sources. Natural sources of copper include geological deposits, volcanic activity, and
weathering and erosion of rocks and soils. Anthropogenic sources of copper include mining activities,
agriculture, automobile brake-pad wear, metal and electrical manufacturing, sludge from publicly
owned treatment works, and pesticide use (EPA, 2019f). Copper is primarily a contaminant of concern
due to its ecotoxicity, as compared to its human health impacts.
4 Note: The impaired river segment is obscured by the Kalispell label on Figure 3.
Toxic-Impaired Waterbodies on 303(d) Lists in the Columbia River Basin
15
-------
* , CiifutFftvj *'•- Sff.fi fkturW¥*
¦¦ 0Jpp«s TMT.'l?
fli Cof,)(»>'• ystefcr* y>
.' J> Ower fost •><
4«!•,'! '-*..X'.' S'RC^W o j s!»i" tfc,-"
Figure 4. Copper impaired waters in the Columbia River Basin. The map is not authoritative and should be used
for reference purposes only. The map is not to be used for legal purposes. Impaired waterbody segments have
been slightly enlarged to improve their visibility and are not to scale.
Multiple TMDL planning areas in Montana have a copper TMDL; there are no category 5 copper
impaired waters in Montana's portion of the Basin without an approved TMDL (Figure 4). In Idaho,
copper impairs rivers in the Hells Canyon, the Middle Salmon-Panther, and Coeur d'Alene River basins;
the Lower Clark Fork River has a copper TMDL. In Washington State, copper impairs streams in the Lake
Chelan and Lower Cowlitz River watersheds. Oregon has identified the greatest extent of category 5
copper-impaired waters. The Owyhee, Willamette, Hood, and Lower Columbia River watersheds contain
at least one waterbody with an identified category 5 copper impairment. There are no copper TMDLs in
Oregon's portion of the Basin (Table 4).
Toxic-Impaired Waterbodies on 303(d) Lists in the Columbia River Basin 16
-------
Table 4. Watersheds with copper impaired waters.
State
Location of impaired waters without a TMDL
Location of EPA-approved TMDLs
(Category 5)
(Category 4a)
Idaho
Hells Canyon, Middle Salmon-Panther, and
Coeur d'Alene River watersheds
Lower Clark Fork River watershed
Montana
None
Blackfoot Headwaters, Clark Fork -
Drummond, Silver Bow Creek -
Clark Fork River, Flint Creek
watershed, Kootenai - Fisher, Little
Blackfoot River, Thompson Project,
Blackfoot River - Nevada, Ninemile,
Rock Creek, and Upper Clark Fork
River
Oregon
Owyhee, Willamette, Hood River, and Lower
Columbia River watersheds
None
Washington
Lake Chelan and Lower Cowlitz River watersheds
None
Note: The Montana TMDLs are listed by the name of their respective planning areas.
Lead
Although the element occurs naturally in the Earth's crust, human activities are the primary source of
lead in the aquatic environment. Industrial processes and mining activities may release significant
quantities of lead into the environment (EPA, 2019e). In the past, the combustion of leaded gasoline was
a major pathway into the air and aquatic environments. A gradual phase-out of leaded gasoline was
implemented between 1975 and 1996. Due to EPA regulations, the national average lead concentration
in ambient air deceased by 99% between 1980 and 2018 (EPA, 2019b).
Toxic-Impaired Waterbodies on 303(d) Lists in the Columbia River Basin
17
-------
i*W
Sf
-
¦" " ft JJsvai i'Viyui.tev
Ml t--i- ->OU
—i 1«ks Waww f-T^rt <1
f *t I '>
if1-Ms'
18ft
\ I
•f
V'":
Figure 5. Lead impaired waters in the Columbia River Basin. The map is not authoritative and should be used for
reference purposes only. The map is not to be used for legal purposes. Impaired waterbody segments have been
slightly enlarged to improve their visibility and are not to scale.
Mining or industrial activities are the primary causes of lead impairments. Idaho has the greatest
number of identified category 5 impairments in the Columbia River Basin (Figure 5). The Coeur d'Alene
River, Upper Spokane River and Lower Kootenai River watersheds contain at least one waterbody listed
as impaired by lead. The East Fork of Eagle Creek in the Upper Coeur d'Alene River watershed has a lead
TMDL. In Oregon, lead impairments without an approved TMDL occur in the Owyhee River watershed. A
lead TMDL was developed for the Columbia Slough in the Willamette River watershed in 1998, but
recent water quality monitoring data indicates the watershed is achieving water quality standards for
aquatic life and the watershed is listed as category 2 for lead in the state's final 2018/2020. The Lake
Chelan watershed is the only Washington basin with lead-impaired waters without an approved TMDL.
A lead TMDL has been developed in the Spokane River watershed. Within Montana's portion of the
Basin there are nine lead TMDLs and there are no identified category 5 lead impairments.
Toxic-Impaired Waterbodies on 303(d) Lists in the Columbia River Basin
18
-------
Table 5. Watersheds with lead impaired waters.
State
Location of impaired waters without a TMDL
Location of EPA-approved TMDLs
(Category 5)
(Category 4a)
Idaho
Coeur d'Alene River, Upper Spokane River and
Lower Kootenai River watersheds
Upper Coeur d'Alene River
Montana
None
Bitterroot River, Blackfoot
Headwaters, Clark Fork-
Drummond, Clark Fork - Silver Bow
Creek, Flint Creek, Kootenai -
Fisher Project, Little Blackfoot
River, Middle Blackfoot River,
Ninemile, Prospect Creek, Rock
Creek, and Upper Clark Fork River
Oregon
Owyhee River watershed
None
Washington
Lake Chelan watershed
Spokane River watershed
Note: The Montana TMDLs are listed by the name of their respective planning areas.
Mercury
Mercury is a naturally occurring metal that cycles through various chemical and physical forms in the
environment. Inorganic mercury can enter the water or soil from the weathering of rocks that contain
inorganic mercury salts. The inorganic mercury ore found at mining sites is often composed of mercuric
sulfide or cinnabar. Elemental mercury is a shiny liquid at room temperature that is used in older
thermometers, fluorescent lightbulbs, batteries and other products. Mercury enters waterways through
multiple sources, including atmospheric deposition (e.g. coal combustion), industrial (e.g. gold
production) or wastewater discharges, mining activities, or stormwater runoff (EPA, 2019j). Bacteria can
convert inorganic mercury in the aquatic environment into methylmercury, a form of the element that
readily bioaccumulates in organisms and biomagnifies in the food chain - which can lead to elevated
levels of mercury in the tissue of predator species, including birds, and resident fish caught for human
consumption. Elevated levels of methylmercury in fish tissues can lead to recommendations to restrict
consumption of resident fish species (i.e. fish advisories). There are numerous fish advisories due to
mercury in all Basin states, including statewide advisories for bass in Idaho, Oregon, and Washington.
For information on specific advisories, refer to EPA's Columbia River Health Advisories webpage.
Toxic-Impaired Waterbodies on 303(d) Lists in the Columbia River Basin
19
-------
tHft'
\ OtM
¦£ OpgiMrectHmr cmrtrfc&inii wtrfCifr'tfBLhet Owtmjnltt
I I Columbia R. Basin Boundary
H Mercury TMDLs
H Mercury Impaired Waters (Cat. S)
ZID Mercury Impaired Watersheds (Cat. 5)
¦ ¦ Miles
0 20 40 80 120 160
Figure 6. Mercury impaired waters in the Columbia River Basin, The map is not authoritative and should be used
for reference purposes only. The map is not to be used for legal purposes. Impaired waterbody segments have
been slightly enlarged to improve their visibility and are not to scale.
Mercury is the only toxic contaminant that is the cause of Category 5 impaired waters in all four
Columbia River Basin states. Mercury impairments are commonly found in watersheds with historic
and/or active mining activities, and in basins with lakes with large surface areas that receive mercury
through atmospheric deposition.
Methylmercury impairs significant lengths of the mainstem Columbia and Snake Rivers (Figure 6). A
small section of Lake Roosevelt south of Kettle Falls, WA is listed as impaired for mercury. The lower
mainstem Columbia River immediately upstream of McNary Dam down to Eagle Creek immediately
above Bonneville Dam and the Columbia River estuary below Puget Island are impaired for
methylmercury.
On the upper Snake River, mercury impairs the reach between Idaho Falls, ID and the upstream
boundary of the American Falls Reservoir, as well as Walcott Lake, the impounded water behind
Minidoka Dam. Farther downstream, methylmercury impairments cover the mainstem Snake River
beginning where it crosses into Oregon east of Caldwell, ID, through Hells Canyon, Oxbow and Brownlee
Reservoirs, and downstream to the northeastern tip of Oregon's state boundary. The Snake River is also
impaired for mercury from Lower Granite Dam to Penawawa Canyon, WA.
Toxic-Impaired Waterbodies on 303(d) Lists in the Columbia River Basin
20
-------
In Idaho, mercury impairs lakes and tributary river reaches in the Owyhee, Boise, Payette, Bruneau,
Coeur d'Alene, Kootenai, Salmon, Goose, and Upper Snake River basins. Idaho developed a mercury
TMDL that covers the Salmon Falls Creek Reservoir within the Upper Snake River watershed. In
Montana's Flathead River watershed, Whitefish and Flathead Lakes are impaired for mercury. Tributary
basins in Oregon with mercury or methylmercury impairments include the Owyhee, Malheur, Powder,
John Day, Deschutes, Sandy, and Willamette River watersheds. Tributary watersheds with mercury
impairments in Washington include the Pend Oreille River, Lake Chelan, and Cowlitz River.
Table 6. Watersheds with mercury impaired waters.
State
Location of impaired waters without a TMDL
Location of EPA-approved TMDLs
(Category 5)
(Category 4a)
Idaho
Mainstem Snake River;
Owyhee, Boise, Payette, Bruneau, Coeur d'Alene,
Kootenai, Salmon, Goose, and Upper Snake River
watersheds
Upper Snake River watershed
Montana
Flathead River watershed
Clark Fork - Drummond, Clark
Fork - Silver Bow Creek, Flint
Creek, Little Blackfoot, Ninemile,
and Rock Creek
Oregon
Mainstem Columbia and Snake Rivers;
Owyhee, Malheur, Powder, John Day, Deschutes,
Sandy, and Willamette River watersheds
Willamette River watershed
Washington
Mainstem Columbia and Snake Rivers;
Lake Chelan, Pend Oreille, and Cowlitz River
watersheds
None
Note: The Montana TMDLs are listed by the name of their respective planning areas.
Selenium
Selenium is a naturally occurring element found in sedimentary rocks, shales, coal and phosphate-
containing soils. Selenium can be released into water naturally through the weathering of selenium-
containing rocks, and by human activities such as surface mining, coal-fired power plants, and irrigated
agriculture (EPA, 2019g). Selenium's toxicity to livestock is the major effect of concern.
Toxic-Impaired Waterbodies on 303(d) Lists in the Columbia River Basin
21
-------
I I Columbia R. Bawn Boundary
HI Selenium TMDLs
IB Selenium Impaired Waters (Cat 5)
120
160
¦£ OpgiMrectHmr cmiufe&rfc Owtmjnltt
Totiicea Eyi. NEJel,
Figure 7. Selenium impaired waters in the Columbia River Basin. The map is not authoritative and should be used
for reference purposes only. The map is not to be used for legal purposes. Impaired waterbody segments have been
slightly enlarged to improve their visibility and are not to scale.
Selenium impairments are found in regions with historic or active mining activities. Affected Idaho
basins include the Blackfoot and Salt River watersheds. In Montana, Lake Koocanusa in the Upper
Kootenai watershed is impaired/threatened for selenium and there is a Selenium TMDL in the Upper
Clark River watershed planning area (Figure 7). There are no identified selenium impairments in Oregon
or Washington.
Table 7. Watersheds with selenium impaired waters.
State
Location of impaired waters without a TMDL
(Category 5)
Location of EPA-approved TMDLs
(Category 4a)
Idaho
Blackfoot and Salt River watersheds
None
Montana
Upper Kootenai River watershed
Upper Clark Fork River watershed
Oregon
None
None
Washington
None
None
Note: The Montana TMDL is listed by the name of its planning area.
Toxic-Impaired Waterbodies on 303(d) Lists in the Columbia River Basin
22
-------
Pesticides
Aldri n/Dield rin
Aldrin and Dieldrin are legacy organochlorine insecticides with similar chemical structures that were
used in agriculture, timber preservation, and in rubber coverings of electrical and telecommunication
cables (EPA, 2003). EPA banned both chemicals in 1987. Aldrin degrades in the environment to form
Dieldrin, and as a result, the pesticides are considered "linked" together for the purposes of this
document (Agency for Toxic Substances and Disease Registry [ATSDR], 2011). Aldrin and Dieldrin cause
human liver toxicity and are classed as probable carcinogens by EPA's IRIS program (EPA, 2017d). Aldrin
and/or Dieldrin impair waterbodies in basins due to past agricultural activities.
§ QpenStretfHn contri
v»ttori#
Qlytnp**
I I Columbia R. Basin Boundary
¦I Aldnn/DieWnn TMDLs
¦i Aldrin/Dtekirin Impaired Waters (Cat. S)
I I Aldrm/DteJdnn Impaired Watersheds (Cat 5)
MlISS
0 20 40 80 120 160
ComKMnfv
Figure 8. Aldrin and/or Dieldrin impaired waters in the Columbia River Basin. The extent of the TMDLfor Dieldrin
in the Columbia Slough watershed is not shown. The map is not authoritative and should be used for reference
purposes only. The map is not to be used for legal purposes. Impaired waterbody segments have been slightly
enlarged to improve their visibility and are not to scale.
Impairments on the mainstem Columbia River include the reach upstream of the Saddle Mountain
National Wildlife Refuge and several reaches in the lower Columbia upstream and downstream of
Longview, WA. There is a TMDL covering Dieldrin within the Snake River - Hells Canyon reach.
In Washington, Aldrin and/or Dieldrin impair rivers in the following watersheds: Pend Oreille River,
Colville River, Lake Chelan, Palouse River, Crab Creek, Upper Columbia-Priest Rapids, Yakima River,
Toxic-Impaired Waterbodies on 303(d) Lists in the Columbia River Basin
23
-------
Lower Columbia-Clatskanie. In Oregon, the pesticide and/or its breakdown product impairs waters in the
Owyhee, Malheur, Deschutes, Hood, Sandy, and Willamette River basins. There are two TMDLs for
Dieldrin in the Willamette River watershed for the Columbia Slough (not shown)5 and Lower Willamette
River subbasin (Figure 8). No Aldrin or Dieldrin category 5 impairments have been identified in Idaho or
Montana's portion of the Basin.
Table 8. Watersheds with Aldrin and/or Dieldrin impaired waters.
Location of impaired waters without a TMDL
(Category 5)
Idaho None
Montana None
Oregon Mainstem Columbia and Snake Rivers;
Owyhee, Malheur, Deschutes, Hood, Sandy, and
Willamette River watersheds
Location of EPA-approved TMDLs
(Category 4a)
Snake River - Hells Canyon
watershed
None
Snake River - Hells Canyon and
Willamette River watersheds
Washington
Mainstem Columbia and Snake Rivers;
Upper Columbia-Priest Rapids, Lower Columbia-
Clatskanie, Pend Oreille, Colville, Lake Chelan,
Palouse, Crab Creek, Yakima River watersheds
Palouse, Walla Walla, and Yakima
River watersheds
Chlorpyrifos
Chlorpyrifos is a current-use organophosphate insecticide used since 1965 to control a variety of pests,
including mites and ticks. The chemical is applied to agricultural crops including fruit and nut trees,
Brussel sprouts, broccoli, cauliflower, and other row crops. Additionally, the insecticide is applied for
non-agricultural purposes including on golf courses, turf, and found in non-structural wood treatments
such as utility poles or fence posts. Chlorpyrifos is also registered as a mosquito adulticide and for use in
roach and ant bait stations (EPA, 2019c). The pesticide affects the nervous system of insects by inhibiting
acetylcholinesterase, a key enzyme associated with regulating nerve impulses. Chlorpyrifos may also
affect human nervous system function (ATSDR, 1997). Regulatory restrictions, including a statewide ban
in California beginning in 2021 and an expected ban of the chemical in the European Union, are
projected to reduce demand for the pesticide. The world's largest producer of Chlorpyrifos, Corteva,
announced in February 2020 the company would no longer produce the chemical by the end of the year,
citing declining sales (Polansek, 2020).
5 There was never a 303(d) listing for Dieldrin in the Columbia Slough watershed. The TMDL was developed as a
preventative TMDL before any listing occurred (Becky Anthony [Water Quality Assessment Lead, Oregon
Department of Environmental Quality], personal communication, May 5, 2020).
Toxic-Impaired Waterbodies on 303(d) Lists in the Columbia River Basin
24
-------
I I Columbia R. Basin Boundary
¦¦ Chtorpynfos Impaired Waters (Cat. 5)
I 1 CWorpyrrfos lmpa*ed Watersheds (Cat. 5)
120
160
¦£ OpgiMrectHmr cmrtrfc&inii wtrfCifr'tfBLhet Owtmjnltt
Totiicea Eyi. NEJel,
Figure 9. Chlorpyrifos impaired waters in the Columbia River Basin. The map is not authoritative and should be
used for reference purposes only. The map is not to be used for legal purposes. Impaired waterbody segments
have been slightly enlarged to improve their visibility and are not to scale.
Chlorpyrifos impairments are have been identified in agricultural basins and near urban centers. In
Idaho, elevated concentrations of Chlorpyrifos impair designated uses on tributaries in the Lower Boise
River watershed and in a tributary to Brownlee Reservoir (Figure 9). Oregon has category 5 listed
chlorpyrifos-impaired streams in the Walla Walla, Deschutes, and Willamette River basins. In
Washington State, Chlorpyrifos impairments affect the Wenatchee and Yakima River basins. There are
no identified impairments in the state of Montana.
Table 9. Watersheds with Chlorpyrifos impaired waters.
State
Location of impaired waters without a TMDL
Location of EPA-approved TMDLs
(Category 5)
(Category 4a)
Idaho
Lower Boise River and Brownlee Reservoir
watersheds
None
Montana
None
None
Oregon
Walla Walla, Deschutes, and Willamette River
watersheds
None
Washington
Wenatchee and Yakima River watersheds
None
Toxic-Impaired Waterbodies on 303(d) Lists in the Columbia River Basin
25
-------
Dichlorodiphenyltrichloroethane (DDT)
DDT is an orgariochlorine compound that was widely used to address insect-borne diseases and to
control agricultural and household pests beginning in the 1940s. DDT-type chemicals primarily act on
the peripheral nervous system by affecting sodium channels in nerve cells (Coates, 1990). The chemical
persists in the environment and accumulates in fatty tissues. The compound causes predatory birds to
lay eggs with thinner shells, decreasing the viability of their offspring. In the soil DDT breaks down into
metabolites including dichlorodiphenyldichloroethylene (DDE) and dichlorodiphenyldichloroethane
(DDD). In 1972, EPA banned the chemical for use in the U.S. due to its adverse impacts to wildlife and
potential human health risks (EPA, 2019d). EPA's IRIS program classifies DDT as having liver toxicity and
as a carcinogen and classifies DDT's metabolites, DDE and DDD, as carcinogens (EPA, 2Q17e). The
following overview of 303(d) listings in the Basin does not differentiate between DDT and its breakdown
products - hereafter "DDT" refers to all three compounds. DDT impairs surface waterbodies in basins
with significant historic agricultural activities in Oregon and Washington.
¦g OpenSli confyi
I I Columbia R. Basin Boundary
¦i DDT TMDLs
¦I DDT impaired Waters (Cat S)
I I DDT Impaired Watersheds (Cat S)
¦ ¦ Miles
0 20 40 80 120 160
Figure 10, DDT impaired waters in the Columbia River Basin. The map is not authoritative and should be used for
reference purposes only. The map is not to be used for legal purposes. Impaired waterbody segments have been
slightly enlarged to improve their visibility and are not to scale.
The mainstem Columbia and Snake Rivers have multiple reaches impaired by DDT. Impairments on the
Columbia cover: small portions of Lake Roosevelt and Lake Entiat; reaches above and below the City of
Wenatchee, WA; the reach upstream of the mouth of Crab Creek; reaches bracketing the Saddle
Toxic-Impaired Waterbodies on 303(d) Lists in the Columbia River Basin
26
-------
Mountain National Wildlife Refuge; and portions of Lake Wallula and Lake Umatilla. DDT impairs the
lower Columbia River between Bonneville Dam and the Sandy River confluence and from Kalama, WA to
the mouth of the Estuary. Oregon and Idaho jointly issued a TMDL covering DDT impairments within the
Hells Canyon complex. Between Lewiston, ID, and the confluence with the Columbia, the Snake River
has multiple segments with identified category 5 impairments for DDT.
Oregon watersheds with category 5 DDT impairments include the Owyhee, Malheur, Deschutes, Hood6,
and Willamette River basins (Figure 10). There are three DDT TMDLs in the Willamette Basin: in the
Columbia Slough, Lower Willamette River subbasin, and the Molalla-Pudding subbasins. In Washington,
there are category 5 DDT impaired waters in the following tributary basins: Crab Creek, Colville River,
Okanogan River, Spokane River, Rock Creek, Walla Walla River, Yakima River, Wenatchee River, Lake
Chelan watershed, and the Upper Columbia-Priest Rapids and -Entiat watersheds. TMDLs for DDT have
been developed in the Lake Chelan, and Lower Okanagan, Walla Walla, Wenatchee, and Yakima River
watersheds. There are no identified category 5 DDT impairments in Idaho or Montana's portion of the
Basin.
Table 10. Watersheds with DDT impaired waters.
Idaho
Montana
Oregon
Washington
Location of impaired waters without a TMDL
(Category 5)
None
None
Mainstem Columbia and Snake Rivers;
Owyhee, Malheur, Deschutes, Hood, and
Willamette River watersheds
Mainstem Columbia and Snake Rivers;
Crab Creek, Lake Chelan, Upper Columbia-Priest
Rapids and -Entiat, Colville, Okanogan, Spokane,
Rock Creek, Walla Walla, Yakima, and
Wenatchee River watersheds
Location of EPA-approved TMDLs
(Category 4a)
Snake River - Hells Canyon
watershed
None
Willamette River watershed
Lake Chelan, Lower Okanogan,
Walla Walla, Wenatchee, and
Yakima River watersheds
Persistent Organic Pollutants
Polycyclic Aromatic Hydrocarbons (PAHs)
PAHs are a group of over 100 different chemicals that are formed during combustion processes, in
particular the incomplete burning of coal, oil and gas, garbage, or other organic substances like tobacco
or charbroiled meat (Northwest Power and Conservation Council and Columbia River Toxics Reduction
Working Group, 2018). Some PAHs are manufactured. Most PAHs do not dissolve easily in water and
bind to solid particles that settle to the bottom of rivers and lakes. Major sources of PAHs in the air
include volcanic eruptions, motor vehicle exhaust, wood smoke, and municipal trash incineration
facilities (ATSDR, 1996). In 2018, the Northwest Power and Conservation Council and Columbia River
Toxics Reduction Working Group developed a StoryMap of available PAH data in water and soil
sediment in the Basin. Visit the Northwest Power and Conservation Council's website to view the map.
The major PAH toxic effect of concern is that certain PAHs are carcinogenic to humans. EPA's IRIS
6 Includes Threemile Creek that drains the east flank of Mt. Hood and discharges directly into the Columbia River
near The Dalles, OR.
Toxic-Impaired Waterbodies on 303(d) Lists in the Columbia River Basin
27
-------
program has recently updated the toxicity information for a key carcinogenic PAH, benzo[a]pyrene (EPA,
2017c).
I I Columbia R. Basin Boundary
WM PAH Impaired Waters (Cat. 5)
I I PAH Impaired Watersheds (Cat. 5)
120 160
•t OpwiMr«
-------
Polychlorinated Biphenyls (PCBs)
PCBs are a group of 209 man-made organic chemicals consisting of carbon, hydrogen and chlorine
atoms. PCBs belong to a broad family of chemicals known as chlorinated hydrocarbons. PCBs have a
range of toxicity and vary in consistency from thin, light-colored liquids to yellow or black waxy solids.
EPA's IRIS program classifies PCBs as having both cancer and non-cancer toxicity (EPA, 2017f). Between
1929 and 1979 PCBs were manufactured domestically. Commercial PCB mixtures made by the Monsanto
corporation were known as Aroclors. Each Aroclor was identified by a number identifying the
percentage of chlorine in the mixture. Higher chlorination is generally associated with greater toxicity.
For example, Aroclor 1254 is 54% chlorine by weight adversely and is known to affect the human
immune system (EPA, 2017a). In 1979, the U.S. banned the manufacturing of PCBs. PCBs do not readily
break down in the environment and can remain for long periods cycling between the air, water and soil.
The chemicals can be carried long distances and have been found in snow and seawater in areas far
from where they were released into the environment. Legacy PCBs may be present in products and
materials produced before the 1979 PCB ban including in transformers and other electrical equipment,
oil, fluorescent lights, and other products (EPA, 2019h). More recently, there have also been concerns
about non-legacy PCBs that may arise as manufacturing by-products (Rodenburg et al., 2015).
Toxic-Impaired Waterbodies on 303(d) Lists in the Columbia River Basin
29
-------
¦£ OpgiMrectHmr cmrtrfc&inii wtrfCifr'tfBLhet Comnjntt
I 1 Columbia R. Basin Boundary
H PCB THDLS
I i PCB TMDLs m Watersheds
H PCB Impaired Waters (Cat 5)
¦ m — i^— Miles
0 20 40 80 120 160
vtctoh*
Ol\*Tipi •
Figure 12. PCB impaired waters in the Columbia River Basin. The map is not authoritative and should be used for
reference purposes only. The map is not to be used for legal purposes. Impaired waterbody segments have been
slightly enlarged to improve their visibility and are not to scale.
The mairistem Columbia River has identified category 5 impairments in the following locations: portions
of Lake Roosevelt and Lake Entiat; reaches above and below the City of Wenatchee, WA; the reach
upstream of the mouth of Crab Creek; reaches bracketing the Saddle Mountain National Wildlife Refuge;
a portion of Lake Wallula above McNary Dam; the entire length of lower Columbia River between
McNary Dam and the Sandy River confluence; and the estuary below Kalama, WA.
The following Washington watersheds have category 5 impaired waters: Pend Oreille River, Colville
River, Spokane River, Rock Creek, Palouse River, Crab Creek, Upper Columbia-Entiat, Banks Lake,
Okanogan River, Lake Chelan, Wenatchee River, Yakima River, Cowlitz River, and Lower Columbia-
Clatskanie (Figure 12). Washington has developed PCB TMDLs in the Lake Chelan, Lower Okanogan
River, Palouse River, and Walla Walla River watersheds. Oregon has identified a category 5 PCB
impairment on the lower Willamette River and a PCB TMDL covers the Columbia Slough in the
Willamette River watershed. In Montana's Flathead River watershed, Whitefish Lake and River, and
Flathead Lake are impaired by PCBs.
Toxic-Impaired Waterbodies on 303(d) Lists in the Columbia River Basin
30
-------
Table 12. Watersheds with waters impaired by PCBs.
Location of impaired waters without a TMDL
(Category 5)
Location of EPA-approved TMDLs
(Category 4a)
Idaho None
Montana Flathead River
Oregon Mainstem Columbia River;
None
None
None
Columbia Slough
Willamette River
Washington Mainstem Columbia River;
Lake Chelan, Lower Okanogan
River, Palouse River, Walla Walla
River watersheds
Pend Oreille River, Colville River, Spokane River,
Rock Creek, Palouse River, Crab Creek, Upper
Columbia-Entiat, Banks Lake, Okanogan River,
Lake Chelan, Wenatchee River, Yakima River,
Cowlitz River, Lower Columbia-Clatskanie
watersheds
Total Maximum Daily Loads for Toxic Contaminants
In total, 31 TMDLs that address at least one toxic contaminant have been developed and approved by
EPA in the Columbia River Basin. A TMDL specifies the maximum amount of a pollutant that can enter a
waterbody so that the waterbody will meet, and continue to meet, water quality standards. All
contributing sources of the pollutants (point and nonpoint sources) are identified, and they are allocated
a portion of the allowable load that usually contemplates a reduction in their pollution discharge in
order to help solve the problem (EPA, 2018b). For more information on TMDLs, refer to EPA's website7.
The following section includes all toxics-related TMDLs and associated implementation plans within the
Basin. Appendix B provides a table that identifies the toxic pollutants covered by the TMDLs.
Implementing a TMDL involves applying pollution control practices to reduce the pollutant loads to the
extent determined necessary in the TMDL. These practices usually consist of point source control
permits and/or non-point source control best management practices (BMPs) (EPA, 2018a). Although
states are not explicitly required under CWA Section 303(d) to develop TMDL implementation plans,
many states develop implementation plans. EPA is not required to and does not approve TMDL
implementation plans.
TMDL implementation plans, which may be referred to as "Water Quality Improvement Plans" or
"Watershed Restoration Plans," may provide additional information on what point and nonpoint sources
contribute to the impairment and how those sources are being controlled, or should be controlled, in
the future (EPA, 2018b). This could include identification of a range of potential management measures
and practices that might be feasible for addressing the main loading sources in the watershed (EPA,
2008).
While implementation plans are specific to the watersheds and pollutants for which they are develop,
many pollutant sources and potential pollution control actions to address toxics are similar across the
basin. In Montana, the majority of toxics TMDLs are for metals and were developed to address waters
impaired by historic mining practices. As a result, the implementation plans primarily focus on
reclamation/restoration of abandoned mine sites, mine waste clean-up, and source assessment or
7 URL: https://www.epa.gov/tmdl/overview-total-maximum-dailv-loads-tmdls
Toxic-Impaired Waterbodies on 303(d) Lists in the Columbia River Basin 31
-------
monitoring. For organochlorine pesticides, such as DDT, implementation plans focus on keeping
sediment from entering the waterways through agricultural and urban best management practices, such
as cover crops, conservation tillage, more efficient irrigation methods, riparian buffers, and green
infrastructure. Refer to implementation plans for site-and-parameter specific actions.
Idaho
Lower Clark Fork River Watershed:
Table 13. Toxic pollutants with approved TMDLs in the Lower Clark Fork River watershed.
Toxic Contaminant
Date of EPA-Approved TMDL
Cadmium
Copper
2007
Zinc
For specific information on the location and extent of toxics-impairments, refer to the Lower Clark Fork
River Subbasin Assessment and Total Maximum Daily Loads8. In 2014, the Lower Clark Fork River
Subbasin 17010213 Agricultural TMDL Implementation Plan9 was developed, but it does not address
toxics.
Portneuf River Watershed:
In 2001, EPA approved a TMDL for oil and grease in the Portneuf River watershed. For specific
information on the location and extent of the impairment(s), refer to the Portneuf River TMDL10. The
Portneuf River TMDL Implementation Plan, released in 2003, does not address the oil and grease
impairment. In 2010, EPA approved a revision to the original TMDL. Refer to the updated TMDL, the
Portneuf River TMDL Revision and Addendum11, for updated information and context related to the oil
and grease impairment.
Snake River - Hells Canyon Watershed12:
Table 14. Toxic pollutants with approved TMDLs in the Snake River - Hells Canyon watershed.
Toxic Contaminant
Date of EPA-Approved TMDL
DDD
DDE
2004
DDT
| Dieldrin
For specific information on the location and extent of toxics-impairments, refer to the Snake River -
Hells Canyon Total Maximum Daily Load13. The implementation plans for Oregon and Idaho are detailed
8 Document URL: https://www.deq.idaho.gov/media/453494-
water data reports surface water tmdls dark fork lower dark fork lower entire.pdf
9 Document URL: https://www.deq.idaho.gov/media/60176892/lower-clark-fork-river-agricultural-tmdl-
implementation-plan.pdf
10 Document URL: https://www.deq.idaho.gov/media/464480-
water data reports surface water tmdls portneuf river portneuf river entire.pdf
11 Document URL: https://www.deq.idaho.gov/media/464542-
water data reports surface water tmdls portneuf river portneuf river revision addendum final.pdf
12 Idaho and Oregon jointly developed the Snake River - Hells Canyon TMDL. The table and accompanying text are
also included in the list of Oregon's TMDLs.
13 Document URL: https://www.deq.idaho.gov/media/454498-snake river hells canyon entire.pdf
Toxic-Impaired Waterbodies on 303(d) Lists in the Columbia River Basin
32
-------
in the TMDL. Actions to address the pesticide impairments are focused on sediment management.
Specifically, public awareness campaigns, erosion control and reduction measures, implementation of
agricultural best management practices, and riparian area management, including revegetation and
streambank stability efforts.
Upper Coeur d'Alene River Watershed:
Table 15. Toxic pollutants with approved TMDLs in the Upper Coeur d'Alene River watershed.
Toxic Contaminant
Date of EPA-Approved TMDL
Cadmium
Lead
2002
Zinc
For specific information on the location and extent of the toxics-related impairments, refer to the
Subbasin Assessment and Total Maximum Daily Loads of the North Fork Coeur d'Alene River14. The
Implementation Plan has not been released as of May 2020.
Upper Snake River Watershed:
Table 16. Toxic pollutants with approved TMDLs in the Upper Snake River watershed.
Toxic Contaminant Date of EPA-Approved TMDL
Mercury 2002
For specific information on the location and extent of the mercury impairment, refer to the Salmon Falls
Creek Subbasin Assessment and Total Maximum Daily Loads15. The Salmon Falls Creek Subbasin
Agricultural TMDL Implementation Plan HUC 1704021316 does not address the mercury impairment in
the watershed.
Montana
Bitterroot River Watershed:
Table 17. Toxic pollutants with approved TMDLs in the Bitterroot River watershed.
Toxic Contaminant Date of EPA-Approved TMDL
Aluminum
Lead
2014
For specific information on the location and extent of the toxics-related impairments, refer to the Final
Bitterroot Watershed Total Maximum Daily Loads and Water Quality Improvement Plan17. The
Implementation Plan does not identify specific actions to address the aluminum and lead pollution
because the sources of the contamination are unclear. Therefore, the document calls for additional
monitoring actions, including investigations into abandoned mines and waste disposal sites, a review of
a wastewater treatment plant's effluent data, streambank sediment sampling above and below
automobile rip-rap sections of the stream, and soil and bedrock sampling to understand background
loads.
14 Document URL: https://www.deq.idaho.gov/media/453947-
water data reports surface water tmdls cda river nf cda river nf entire.pdf
15 Document URL: https://www.deq.idaho.gov/media/463815-salmon falls creek entire.pdf
16 Document URL: https://www.deq.idaho.gov/media/1117962/salmon-falls-creek-sba-ag-tmdl-implementation-
plan.pdf
17 Document URL: http://deq.mt.gov/Portals/112/water/wqpb/CWAIC/TMDL/C05-TMDL-04a.pdf
Toxic-Impaired Waterbodies on 303(d) Lists in the Columbia River Basin
33
-------
Blackfoot Headwaters TMDL Planning Area:
Table 18. Toxic pollutants with approved TMDLs in the Blackfoot Headwaters planning area.
Toxic Contaminant Date of EPA-Approved TMDL
Aluminum
Cadmium
Copper
Iron 2003
Lead
Manganese
Zinc
For specific information on the location and extent of the toxics-related impairments, refer to the Water
Quality Restoration Plan for Metals in the Blackfoot Headwaters TMDL Planning Area18. In 2014, the
Blackfoot River Watershed Restoration Plan was released. The document covers the four TMDL planning
areas within the watershed (Blackfoot Headwaters, Middle Blackfoot, Nevada Creek, and Lower
Blackfoot Planning Areas). Specific potential restoration projects to address toxics include mine waste
clean-up efforts at the Mike Horse mine and community outreach and education related to mine clean
up.
Clark Fork - Drummond Planning Area:
Table 19. Toxic pollutants with approved TMDLs in the Clark Fork — Drummond planning area.
Toxic Contaminant Date of EPA-Approved TMDL
Aluminum
Antimony
Arsenic
Cadmium
Copper 2013
Iron
Lead
Mercury
Zinc
For specific information on the location and extent of the toxics-related impairments, refer to the Bonita
- Superior Metals TMDLs19 document.
18 Document URL: http://deq.mt.gov/Portals/112/water/wqpb/CWAIC/TMDL/C03-TMDL-01a.pdf
19 Document URL: http://deq.mt.gov/Portals/112/water/wqpb/CWAIC/TMDL/C02-TMDL-03a.pdf
Toxic-Impaired Waterbodies on 303(d) Lists in the Columbia River Basin
34
-------
Clark Fork River & Silver Bow Creek Planning Area:
Table 20. Toxic pollutants with approved TMDLs in the Clark Fork and Silver Bow Creek planning area.
Toxic Contaminant Date of EPA-Approved TMDL
Arsenic
Cadmium
Copper
Iron 2014
Lead
Mercury
Zinc
For specific information on the location and extent of the toxics-related impairments, refer to the Final
Silver Bow Creek and Clark Fork River Metal TMDLs20.
Flint Creek Watershed:
Table 21. Toxic pollutants with approved TMDLs in the Flint Creek watershed.
Toxic Contaminant Date of EPA-Approved TMDL
Antimony 2012, 2015
I Arsenic
Cadmium
Copper
Iron 2012
Lead
Mercury
Zinc
* In 2015, the Antimony TMDL was developed for Douglas Creek after the metal-impairment was added
to the state's 2014 303(d) list based on new data collected between 2007-2011.
For specific information on the location and extent of the toxics-related impairments, refer to the Flint
Creek Planning Area Sediment and Metals TMDLs and Framework Water Quality Improvement Plan21
and its Addendum22. In 2014, the Granite Headwaters Watershed Group released the Flint Creek
Watershed Restoration Plan. Projects to address metals in the watershed include additional monitoring,
source assessment for mercury, and remediation projects for point and non-point sources, including at
Black Pine Mine and Combination Mine and Mill sites, and the replacement of the City of Phillipsburg's
existing wastewater treatment lagoons.
20 Document URL: http://deq.mt.gov/Portals/112/Water/WQPB/TMDL/PDF/SilverBowCFRMetals/C01-TMDL-
05a.pdf
21 Document URL: http://deq.mt.gov/Portals/112/water/wqpb/CWAIC/TMDL/C02-TMDL-01a.pdf
22 Document URL: http://deq.mt.gov/Portals/112/water/wqpb/CWAIC/TMDL/C02-TMDL-01a-a.pdf
Toxic-Impaired Waterbodies on 303(d) Lists in the Columbia River Basin
35
-------
Kootenai - Fisher Project Area TMDLs:
Table 22. Toxic pollutants with approved TMDLs in the Kootenai - Fisher Project Area.
Toxic Contaminant
Date of EPA-Approved TMDL
Arsenic
Cadmium
Copper
2014
Lead
Zinc
For specific information on the location and extent of the toxics-related impairments, refer to the
Kootenai - Fisher Project Area Metals. Nutrients. Sediment, and Temperature TMDLs and Water Quality
Improvement Plan23. The Kootenai River Basin Watershed Restoration Plan, released by the Kootenai
River Network in 2015, identifies actions to address metal contamination including monitoring the
effectiveness of past clean-up efforts, evaluating the feasibility of cleaning up remaining in-stream,
streambank, and floodplain mine tailings below the Snowshoe Creek site, and reclaiming the mine audit,
mill site, and road at the Troy Mine.
Little Blackfoot River TMDL Planning Area:
Table 23. Toxic pollutants with approved TMDLs in the Little Blackfoot planning area.
Toxic Contaminant
Date of EPA-Approved TMDL
Aluminum
2014*
Arsenic
Beryllium
Cadmium
Copper
2011
Cyanide
Iron
Lead
Mercury
Zinc J
2011, 2014*
* In 2013, Montana DEQ reassessed streams in the Little Blackfoot River TMDL planning area and, based
on new data, developed TMDLs for 9 aluminum impairments and one zinc impairment.
For specific information on the location and extent of the toxics-related impairments, refer to the Little
Blackfoot River Watershed TDMLs and Framework Water Quality Improvement Plan24 and its
Addendum25. Trout Unlimited released the Little Blackfoot River Watershed Restoration Plan in 2016.
The document identifies management measures to address nonpoint sources of metals impairments,
including the consolidation and removal of mine tailings, phytostabilization26, capping, closure of
hazardous mine openings, revegetation, streambank stabilization, mine drainage neutralization with
lime amendments, and passive treatment of audit drainage. Recently completed or ongoing projects
include the reclamation of Ontario, Monarch, Tramway, Lilly Orphan Boy and Telegraph mines.
23 Document URL: http://deq.mt.gov/Portals/112/water/wqpb/CWAIC/TMDL/K01-TMDL-04a.pdf
24 Document URL: https://deq.mt.gov/Portals/112/water/wqpb/CWAIC/TMDL/C01-TMDL-03a.pdf
25 Document URL: https://deq.mt.gov/Portals/112/water/wqpb/CWAIC/TMDL/C01-TMDL-03a-a.pdf
26 Phytostabilization is the use of certain plant species to immobilize contaminants in the soil and ground water
through absorption and accumulation by roots, adsorption onto roots, or precipitation within the root zone.
Toxic-Impaired Waterbodies on 303(d) Lists in the Columbia River Basin
36
-------
Middle Blackfoot-Nevada Creek Planning Area:
Table 24. Toxic pollutants with approved TMDLs in the Middle Blackfoot-Nevada Creek planning area.
Toxic Contaminant
Date of EPA-Approved TMDL
Aluminum
2008
Arsenic
2008, 2014*
Copper
2008
Iron
2008, 2014*
Lead
2008
* High levels of uncertainty due to incomplete assessments and insufficient datasets caused Montana DEQ
to not address multiple impairments in the original 2008 TMDL; one new impairment was identified after
the document's publication. In 2014, Montana DEQ developed an Addendum to the 2008 TMDL.
For specific information on the location and extent of the toxics-related impairments, refer to the
Middle Blackfoot-Nevada Creek Total Maximum Daily Loads and Water Quality Improvement Plan27 and
its Addendum28. The Blackfoot River Watershed Restoration Plan covers the four TMDL planning areas
within the watershed (Blackfoot Headwaters, Middle Blackfoot, Nevada Creek, and Lower Blackfoot
Planning Areas). Specific potential restoration projects to address toxics include mine waste clean-up
efforts at the Mike Horse mine and community outreach and education related to mine clean up.
Ninemile TMDL Planning Area:
Table 25. Toxic pollutants with approved TMDLs in the Ninemile planning area.
Toxic Contaminant
Date of EPA-Approved TMDL
Copper
Lead
2005
Mercury
zinc 1
For specific information on the location and extent of the toxics-related impairments, refer to the Water
Quality Restoration Plan and total Maximum Daily Loads for the Ninemile Planning Area29 document.
Released by Trout Unlimited in 2013, The Watershed Restoration Plan for the Ninemile Creek TMDL
Planning Area identifies the ongoing or completed mine reclamation projects, primarily focused on
sedimentation issues caused by stream channelization following historic placer mining activities.
Completed reclamation projects include Kennedy Creek, Joe Waylett Mine, Mattie V Creek, Little
McCormick Creek, and Eustache Creek.
27 Document URL: http://deq.mt.gov/Portals/112/water/wqpb/CWAIC/TMDL/C03-TMDL-02a.pdf
28 Document URL: http://deq.mt.gov/Portals/112/water/wqpb/CWAIC/TMDL/C03-TMDL-02a-a.pdf
29 Document URL: http://deq.mt.gov/Portals/112/water/wqpb/CWAIC/TMDL/C04-TMDL-01a.pdf
Toxic-Impaired Waterbodies on 303(d) Lists in the Columbia River Basin
37
-------
Prospect Creek TMDL Planning Area:
Table 26. Toxic pollutants with approved TMDLs in the Prospect Creek planning area.
Toxic Contaminant
Date of EPA-Approved TMDL
Antimony
Arsenic
2006
Lead
Ijlns J
For specific information on the location and extent of the toxics-related impairments, refer to the Total
Maximum Daily Loads for Metals in Prospect Creek Watershed: Sanders County. Montana30 document.
The Lower Clark Fork Watershed Restoration Group published the Lower Clark Fork Tributarv Watershed
Restoration Plan in 2019. The document identifies mining reclamation, riparian restoration, education
and outreach filtration, maintenance of in-stream flows, and road management as restoration strategies
to address metals contamination.
Rock Creek TMDL Planning Area:
Table 27. Toxic pollutants with approved TMDLs in the Rock Creek planning area.
Toxic Contaminant
Date of EPA-Approved TMDL
Aluminum
Arsenic
Copper
2013
Iron
Lead
Mercury
For specific information on the location and extent of the toxics-related impairments, refer to the Rock
Creek Watershed Total Maximum Daily Loads and Water Quality Improvement Plans31. The Water
Quality Improvement Plan identifies mining as the principal human-caused source of excess metals
loading. There are 6 sites on the Montana Department of Environmental Quality's Abandoned Hard Rock
Mine Priority List that are considered to have significant human health or safety issues. The goal is the
metals restoration strategy are to prevent metals from waste rock and tailings from migrating into
surface or groundwater, reduce or eliminate concentrated runoff that delivers metal-laden sediment to
surface waters and to identify, prioritize, and select reclamation and restoration options based on
source assessment and risk analysis.
30 Document URL: http://deq.mt.gov/Portals/112/water/wqpb/CWAIC/TMDL/C13-TMDL-02a.pdf
31 Document URL: http://deq.mt.gov/Portals/112/water/wqpb/CWAIC/TMDL/C02-TMDL-02a.pdf
Toxic-Impaired Waterbodies on 303(d) Lists in the Columbia River Basin
38
-------
Thompson Project TMDL Planning Area:
Table 28. Toxic pollutants with approved TMDLs in the Thompson Project planning area.
Toxic Contaminant
Date of EPA-Approved TMDL
Aluminum
Cadmium
2014
Copper
Ijlns J
For specific information on the location and extent of the toxics-related impairments, refer to the
Thompson Project Area Metals. Nutrients. Sediment, and Temperature TMDLs and Water Quality
Improvement Plan32. The Water Quality Improvement Plan identifies mining as the principal human-
caused source of metal contamination. The monitoring plan includes actions to further characterize
impairment conditions and loading sources. Reclamation activities of historic mining disturbances,
removal of old buildings, closure of hazardous mine openings, and filling of caved stopes33 at the Hog
Heaven site have been completed.
Upper Clark Fork River TMDL Planning Area:
Table 29. Toxic pollutants with approved TMDLs in the Upper Clark Fork planning area.
Toxic Contaminant Date of EPA-Approved TMDL
Arsenic
Cadmium
Copper
Cyanide 2010
Iron
Lead
Selenium
Sulfate 2014
Zinc 2010
For specific information on the location and extent of the toxics-related impairments, refer to The Upper
Clark Fork River Tributaries Sediment. Metals, and Temperature TMDLs and Framework for Water
Quality Restoration34 and its Addendum35. In 2012, the Watershed Restoration Coalition released the
Watershed Restoration Plan for the Upper Clark Fork River Tributaries. A key objective of the Watershed
Restoration Plan is the removal of concentrated sources of metals from the floodplain in the lower
drainage. This work is primarily driven by federal Superfund activities.
32 Document URL: http://deq.mt.gov/Portals/112/water/wqpb/CWAIC/TMDL/C13-TMDL-04a.pdf
33 Usually steplike excavations underground for the removal of ore that is formed as the ore is mined in successive
layers (Merriam-Webster, n.d.)
34 Document URL: http://deq.mt.gov/Portals/112/water/wqpb/CWAIC/TMDL/C01-TMDL-02a.pdf
35 Document URL: http://deq.mt.gov/Portals/112/water/wqpb/CWAIC/TMDL/C01-TMDL-02a-a.pdf
Toxic-Impaired Waterbodies on 303(d) Lists in the Columbia River Basin
39
-------
Oregon
Snake River - Hells Canyon Watershed36:
Table 30. Toxic pollutants with approved TMDLs in the Snake River ~ Hells Canyon watershed.
Toxic Contaminant
Date of EPA-Approved TMDL
DDD
DDE
2004
DDT
Dieldrin
For specific information on the location and extent of toxics-impairments, refer to the Snake River -
Hells Canyon Total Maximum Daily Load37. The implementation plans for Oregon and Idaho are detailed
in the TMDL. Actions to address the pesticide impairments are focused on sediment management.
Specifically, public awareness campaigns, erosion control and reduction measures, implementation of
agricultural best management practices, and riparian area management, including revegetation and
streambank stability efforts.
Willamette River Watershed:
Table 31. Toxic pollutants with approved TMDLs in the Willamette River watershed.
Toxic Contaminant Date of EPA-Approved TMDL
Columbia Slough TMDL
2,3,7,8 TCDD(Dioxin)
DDE/DDT
Dieldrin 1998
Lead*
PCBs
Molalla-Pudding Subbasin TMDL
Chlordane
2008
Willamette Basin TMDL
DDT
Dieldrin
Iron
DDT
Dieldrin
Mercury
* Water quality data indicates that the Columbia Slough is now attaining the water quality standards for lead. The
Columbia Slough is classified as category 2 (attaining water quality standards) in the 2018/2020 Integrated Report.
2006
2006, 2019
For specific information on the location and extent of the toxics-related impairments, refer to the
Columbia Slough Total Maximum Daily Load (TMDLs) for: Chlorophyll a. Dissolved Oxygen, pH.
Phosphorus. Bacteria. DDE/DDT, PCBs. Pb. Dieldrin and 2,3,7,8 TCDD38. The TMDL includes an
implementation strategy that identifies stormwater as the largest contributor of PCBs to the Slough and
36 Idaho and Oregon jointly developed the Snake River - Hells Canyon TMDL. The table and accompanying text are
also included in the list of Idaho's TMDLs.
37 Document URL: https://www.deq.idaho.gov/media/454498-snake river hells canyon entire.pdf
38 Document URL: https://www.oregon.gov/deq/FilterDocs/columbiasloughtmdl.pdf
Toxic-Impaired Waterbodies on 303(d) Lists in the Columbia River Basin
40
-------
contributes pesticides as well. The implementation strategy focuses on BMP implementation to control
erosion and monitoring to evaluate the effectiveness of the BMPs.
For specific information on the location and extent of the toxics-related impairments developed in the
Molalla-Pudding subbasin, refer to the Molalla-Pudding Subbasin TMDL & WQMP39. The Water Quality
Management Plan focuses on reducing pesticides and iron by reducing sediment deliveries to streams
by protecting riparian areas, erosion and stormwater control, and low impact development.
In 2006, Oregon developed a TMDL to cover toxic impairments in the Willamette River watershed. For
specific information on the location and extent of the toxic impairments, refer to the Willamette Basin
Total Maximum Daily Loads40. In 2012, a lawsuit was filed challenging the mercury TMDL. As a result,
Oregon Department of Environmental Quality submitted the Revised Willamette Basin Mercury TMDL in
November 2019. EPA disapproved the Revised Willamette Basin Mercury TMDL submitted by Oregon on
November 29, 2019. Under the Clean Water Act, when EPA disapproves a TMDL, EPA must issue a new
TMDL within 30 days. EPA released its Total Maximum Daily Load (TMDL) for Mercury in the Willamette
Basin. Oregon41 on December 30, 2019. The public comment period on EPA's revised mercury TMDL
closed on February 4, 2020. As of May 2020, EPA is considering the received comments. EPA's Total
Maximum Daily Load (TMDL) for Mercury in the Willamette Basin, Oregon is currently in effect for CWA
purposes.
Washington
Lake Chelan Watershed:
Table 32. Toxic pollutants with approved TMDLs in the Lake Chelan watershed.
Toxic Contaminant
Date of EPA-Approved TMDL
DDT
ii n
2006
IfCBS
For specific information on the location and extent of the toxics-related impairments, refer to the Lake
Chelan Watershed DDT and PCB Total Maximum Daily Load: Water Quality Improvement Report42. In
2008, the Lake Chelan DDT and PCB TMDL Water Quality Implementation Plan43 was released. The plan
seeks to prevent contaminated soils from entering surface waters by preventing erosion, safely
disposing unused pesticides, and monitoring trends in fish tissue concentration and contaminant loading
from tributaries. Specific actions identified to achieve these objectives include irrigation and stormwater
BMPs, riparian vegetation buffers, participating in the Washington State Department of Agriculture's
(WSDA) Pesticide Pick up Program and recommendations for constructed wetlands to reduce DDT
loading from tributaries.
39 Document available for download at the following URL: https://www.oregon.gov/deq/wq/tmdls/Pages/TMDLs-
Willamette-Basin.aspx
40 Document URL: https://www.oregon.gov/deq/wq/tmdls/Pages/TMDLs-Willamette-Basin.aspx
41 Document URL: https://www.epa.gov/sites/production/files/2019-12/documents/tmdl-willamette-mercurv-12-
30-2019.pdf
42 Document URL: https://fortress.wa.gov/ecv/publications/documents/0610022.pdf
43 Document URL: https://fortress.wa.gov/ecv/publications/documents/0810048.pdf
Toxic-Impaired Waterbodies on 303(d) Lists in the Columbia River Basin
41
-------
Lower Okanogan River Watershed:
Table 33. Toxic pollutants with approved TMDLs in the Lower Okanogan River watershed.
Toxic Contaminant
Date of EPA-Approved TMDL
DDD
DDE
2004
DDT
IfCBS J
For specific information on the location and extent of the toxics-related impairments, refer to the Lower
Okanogan River Basin DDT and PCBs Total Maximum Daily Load44. In 2008, the Lower Okanogan DDT
PCB Water Quality Implementation Plan (Detailed Implementation Plan) was published. The
Implementation Plan outlines actions to be taken to reduce the movement of contaminants into surface
waters. Specific actions include participation in WSDA's pesticide collection and disposal program, the
efficient delivery of irrigation water and implementation of agricultural BMPs to reduce erosion, and
monitoring of point-source discharges and fish tissues.
Similkameen River Watershed:
In 2004, Washington Ecology developed a TMDL for arsenic in the Similkameen River. For specific
information on the location and extent of impairments, refer to the Lower Similkameen River Arsenic
Total Maximum Daily Load: Submittal Report for Joint Issuance45. The TMDL identified historic mining
practices as the primary human-caused nonpoint source of arsenic. In 2005, the Lower Similkameen
River Arsenic Total Maximum Daily Load (Water Cleanup Plan) was released. No direct actions were
identified to address the contaminated sediments; there is a trend of increasing water quality in the
river. The document prescribes periodic monitoring, monitoring of high-flow events, and the
investigation of impacts from recreational suction dredging to address legacy loads of arsenic in the
Similkameen River.
Palouse River Watershed:
Table 34. Toxic pollutants with approved TMDLs in the Palouse River watershed.
Toxic Contaminant
Date of EPA-Approved TMDL
Dieldrin
2007
PCBs
For specific information on the location and extent of the toxics-related impairments, refer to the
Palouse River Chlorinated Pesticide and PCB Total Maximum Daily Load: Water Quality Improvement
Report and Implementation Plan46. The Implementation Plan focuses on the natural attenuation of
historic contamination and on keeping soil in place to reduce the transport of Dieldrin and PCBs into
surface waterbodies. Specific actions include the adoption of agricultural and stormwater BMPs and
increased monitoring offish tissue data to ensure concentrations of the contaminants continue their
downward trend in the watershed.
44 Document URL: https://fortress.wa.gov/ecv/publications/documents/0410043.pdf
45 Document URL: https://fortress.wa.gov/ecv/publications/documents/0310074.pdf
46 Document URL: https://fortress.wa.gov/ecv/publications/documents/0703018.pdf
Toxic-Impaired Waterbodies on 303(d) Lists in the Columbia River Basin
42
-------
Spokane River Watershed:
Table 35. Toxic pollutants with approved TMDLs in the Spokane River watershed.
Toxic Contaminant
Date of EPA-Approved TMDL
Cadmium
Lead
1999
Zinc
For specific information on the location and extent of the toxics-related impairments, refer to the
Spokane River Dissolved Metals Total Maximum Daily Load47. An Implementation Plan was not
developed to address the excess dissolved metals in the Spokane River watershed.
Walla Walla River Watershed:
Table 36. Toxic pollutants with approved TMDLs in the Walla Walla River watershed.
Toxic Contaminant
Date of EPA-Approved TMDL
Chlordane
DDT
DDE
DDD
t-DDT
2006
Dieldrin
Heptachlor Epoxide
Hexachlorobenzene
Toxaphene
Total PCBs
For specific information on the location and extent of the toxics-related impairments, refer to the Walla
Walla River Chlorinated Pesticides and PCBs Total Maximum Daily Load (Water Cleanup Plan)48. Released
in 2008, the Implementation Plan primarily focuses on actions to reduce erosion to address excess loads
of chlorinated pesticides and PCBs in the watershed. Specific actions include the installation of riparian
buffers and large woody debris to reduce rates of streambank erosion, pasture fence setbacks, wetland
restoration, street sweeping and other stormwater BMPs, household hazardous waste collection events,
the use of less toxic herbicides near surface waterways, and education and outreach activities.
Wenatchee River Watershed:
Table 37. Toxic pollutants with approved TMDLs in the Wenatchee River watershed.
Toxic Contaminant
Date of EPA-Approved TMDL
DDD
DDE
2007
DDT
For specific information on the location and extent of the toxics-related impairments, refer to the
Mission Creek Watershed DDT Total Maximum Daily Load: Water Quality Improvement Report. The
implementation strategy included in the TMDL to address DDT and its breakdown products focuses on
47 Document URL: https://fortress.wa.gov/ecv/publications/documents/9949.pdf
48 Document URL: https://fortress.wa.gov/ecv/publications/documents/0510079.pdf
Toxic-Impaired Waterbodies on 303(d) Lists in the Columbia River Basin 43
-------
additional monitoring, irrigation and stormwater BMPs to reduce soil erosion, participation in the
WSDA's Waste Pesticide Program, and education and outreach assistance.
Yakima River Watershed:
Table 38. Toxic pollutants with approved TMDLs in the Yakima River watershed.
Toxic Contaminant Date of EPA-Approved TMDL
Lower Yakima River Watershed TMDL
DDT
1998
Upper Yakima River Watershed TMDL
DDE
DDT
2002
Dieldrin
For specific information on the location and extent of the toxics-related impairments, refer to the Lower
Yakima River Suspended Sediment and DDT TMDL49 and the Upper Yakima River Suspended Sediment.
Turbidity, and Organochlorine Pesticide TMDL50. An Implementation Plan was not developed for the
Lower Yakima River DDT TMDL. For the Upper Yakima River Organochlorine Pesticide TMDL, the
Implementation Plan focuses on reducing erosion of contaminated soils. Specific recommended actions
include the agricultural BMPs including sedimentation/settling pond; vegetative filter strips; upgraded
irrigation methods; the application of a binding agent, polyacrylamide, to remove suspended soil
particles from irrigation water; conservation tillage; and the use of straw mulch to prevent the
movement of soil.
Columbia River Basin TMDLs
In 1991, the EPA developed a TMDL for Dioxin for the entire Columbia River Basin. For specific
information on the location and extent of the toxics-related impairments, refer to the Total Maximum
Daily Loading (TMDL) to Limit Discharges of 2,3,7.8-TCDD (Dioxin) to the Columbia River Basin51. The
TMDL identified chlorine-bleaching pulp mills as a major source of Dioxin. The TMDL established
wasteload allocations for the mills. No implementation plan was developed for the TMDL.
49 Document URL: https://fortress.wa.gov/ecv/publications/documents/9810202.pdf
50 Document URL: https://fortress.wa.gov/ecv/publications/documents/0210047.pdf
51 Document URL: https://nepis.epa.gov/Exe/ZvPDF.cgi/9100YR95.PDF?Dockev=9100YR95.PDF
Toxic-Impaired Waterbodies on 303(d) Lists in the Columbia River Basin
44
-------
Appendix A. Category 5 Toxics-Impaired Waters in Western Montana
Figure 13. Toxics-impaired waters (both categories 4a and 5) and abandoned mines in western Montana.
• Kalispell
Poison
Missoula
Hamilton
5 Butte
•Abandoned hardrock mines inventoried
by MT DEQ AML and MBMG.
Columbia River Basin within Montana
Flathead Reservation (CSKT)
Priority Abandoned Mine Sites (#100)
Abandoned Mine Sites (#3,800)
Waterbodies
Metals Impairments
Toxic Impairments (PCBs)
Toxics & Metals Impairments
¦ Miles
Montana
Source: U.S. EPA Region 8
Toxic-Impaired Waterbodies on 303(d) Lists in the Columbia River Basin
-------
Appendix B. Toxics TMDLs in the Columbia River Basin
Table 39. Toxics TMDLs in the Columbia River Basin
State Year
Pollutant
ID
2007
Lower Clark
Fork R.
ID
2001
Portneuf R.
ID
2004
Snake R. -
Hells
Canyon
ID
2002
Upper Coeur
d'Alene R.
ID
2002
Upper Snake
R.
MT
2014
Bitterroot R.
MT
2003
Blackfoot
Headwaters
H__
2013
Clark Fork -
Drummond
X X
MT 2014 Clark Fork -
Silver Bow
Cr.
MT 2012/2015 Flint Creek
MT 2014 Kootenai -
Fisher
x x
x
MT
MT
MT
MT
MT
2011/
2014
2008/2014
2005
2006
2013
Little
Blackfoot R.
Middle
Blackfoot-
Nevada Cr.
Ninemile
Propsect Cr.
Rock Cr.
x
x
x
x
X I X
Toxic-Impaired Waterbodies on 303(d) Lists in the Columbia River Basin
46
-------
Pollutant
State
Year
TMDL
E
3
C
E
_3
<
>
£
E
E
o
U
3
3
E
*£
0)
1A
!¦
E
"D
£
0)
(0
<
<
CD
U
MT
MT
OR
OR
OR
2014
2010/2014
2004
1998
2008
OR
WA
WA
WA
WA
WA
WA
2006/2019
2006
2004
2004
2007
1999
2006
Thompson
Project
Upper Clark
Fork R.
Snake R. -
Hells
Canyon
Columbia
Slough
Molalla-
Pudding
Subbasln
Willamette
Basin
Lake Chelan
Lower
Okanogan R.
Similkameen
R.
Palouse R.
Spokane R.
Walla Walla
R.
Wenatchee
R.
Lower
Yakima R.
Upper
Yakima R.
Columbia R.
Basin
x . x
x x x x
x x
x x
x x
x x
xxx
x x
x . x
x . x
Toxic-Impaired Waterbodies on 303(d) Lists in the Columbia River Basin
47
-------
Works Cited
ATSDR. (2011, March 3). Aldrin/Dieldrin. Retrieved from ATSDR website:
https://www.atsdr.cdc.gov/substances/toxsu bstance.asp?toxid=56
ATSDR. (1996). Polycyclic Aromatic Hydrocarbons (PAHs). Atlanta: ATSDR.
ATSDR. (1997). Toxicological Profile for Chlorpyrifos. Atlanta: Agency for Toxic Substances and Disease
Registry. Retrieved from ATSDR: https://www.atsdr.cdc.gov/ToxProfiles/tp.asp?id=495&tid=88
Coats, J. R. (1990). Mechanisms of toxic action and structure-activity relationships for organochlorine
and synthetic pyrethroid insecticides. Environmental Health Perspectives, 87, 255-262.
Columbia River Inter-Tribal Fish Commission. (1994). A fish consumption survey of the Umatilla, Nez
Perce, Yakama and Warm Springs Tribes of the Columbia River Basin. Columbia River Inter-Tribal
Fish Commission Report reference #94-03. Portland, OR.
EPA. (1992). National study of chemical residues in fish, Vol. 1. EPA 823-R-92-008a. Office of Science and
Technology, Washington, D.C.
EPA. (1998). Locating and Estimating Air Emissions from Sources of Arsenic and Arsenic Compounds.
Triangle Park, NC: U.S. EPA.
EPA. (2002). Columbia River Basin Fish Contaminant Survey: 1996-1998. EPA 910-R-02-006. Seattle, WA:
U.S. Environmental Protection Agency Region 10.
EPA. (2003). Contaminant Candidate List Regulatory Determination Support Document for Aldrin and
Dieldrin. Washington, DC: U.S. Environmental Protection Agency.
EPA. (2008). Handbook for Developing Watershed Plans to Restore and Protect Our Waters. Washington,
DC: EPA.
EPA. (2017a, July 28). Aroclor 1254. Retrieved from U.S. EPA IRIS:
https://cfpub.epa.gov/ncea/iris2/chemicalLanding.cfm?substance_nmbr=389
EPA. (2017b, July 28). Arsenic, Inorganic. Retrieved from U.S. EPA IRIS:
https://cfpub.epa.gov/ncea/iris2/chemicalLanding.cfm?substance_nmbr=278
EPA. (2017c, July 28). Benzo[a]pyrene (BaP). Retrieved from U.S. EPA IRIS:
https://cfpub.epa.gov/ncea/iris2/chemicalLanding.cfm?substance_nmbr=136
EPA. (2017d, July 28). Dieldrin. Retrieved from U.S. EPA Website:
https://cfpub.epa.gov/ncea/iris2/chemicalLanding.cfm?substance_nmbr=225
EPA. (2017e, July 28). p,p'-Dichlorodiphenyltrichloroethane (DDT). Retrieved from U.S. EPA IRIS:
https://cfpub.epa.gov/ncea/iris2/chemicalLanding.cfm?substance_nmbr=147
EPA. (2017f, July 28). Polychlorinated Biphenyls (PCBs). Retrieved from U.S. EPA IRIS:
https://cfpub.epa.gov/ncea/iris2/chemicalLanding.cfm?substance_nmbr=294
EPA. (2018a, September 13). Impaired Waters Restoration Process: TMDL Implementation. Retrieved
from U.S. EPA Website: https://www.epa.gov/tmdl/impaired-waters-restoration-process-tmdl-
implementation
EPA. (2018b, September 13). Overview of Total Maximum Daily Loads (TMDLs). Retrieved from U.S. EPA
Website: https://www.epa.gov/tmdl/overview-total-maximum-daily-loads-tmdls
EPA. (2019a, April 8). Toxic and Priority Pollutants Under the Clean Water Act. Retrieved from U.S. EPA
website: https://www.epa.gov/eg/toxic-and-priority-pollutants-under-clean-water-act
EPA. (2019b, July 3). Lead Trends. Retrieved from U.S. EPA website: Air Trends:
https://www.epa.gov/air-trends/lead-trends
EPA. (2019c, July 25). Chlorpyrifos. Retrieved from U.S. EPA website: https://www.epa.gov/ingredients-
used-pesticide-products/chlorpyrifos
EPA. (2019d, August 11). DDT-A Brief History and Status. Retrieved from U.S. EPA Website:
https://www.epa.gov/ingredients-used-pesticide-products/ddt-brief-history-and-status
Toxic-Impaired Waterbodies on 303(d) Lists in the Columbia River Basin 48
-------
EPA. (2019e, August 12). Learn about Lead. Retrieved from U.S. EPA website:
https://www.epa.gov/lead/learn-about-lead
EPA. (2019f, August 15). Aquatic Life Criteria - Copper. Retrieved from U.S. EPA website:
https://www.epa.gov/wqc/aquatic-life-criteria-copper
EPA. (2019g, August 19). Aquatic Life Criterion - Selenium. Retrieved from U.S. EPA website:
https://www.epa.gov/wqc/aquatic-life-criterion-selenium
EPA. (2019h, August 23). Learn about Polychlorinated Biphenyls (PCBs). Retrieved from U.S. EPA
website: https://www.epa.gOv/pcbs/learn-about-polychlorinated-biphenyls-pcbs#what
EPA. (2019i, September 24). About the TSCA Chemical Substance Inventory. Retrieved from U.S. EPA
website: https://www.epa.gov/tsca-inventory/about-tsca-chemical-substance-inventory
EPA. (2019j, October 17). Basic Information about Mercury. Retrieved from U.S. EPA website:
https://www.epa.gov/mercury/basic-information-about-mercury
Harper, B. L., & Walker Jr, D. E. (2015). Comparison of Contemporary and Heritage Fish Consumption
Rates in the Columbia River Basin. Human Ecology, 43(2), 225-236. doi:10.1007/sl0745-015-
9734-4
Hink, J.E., Schmitt, C.J., Bartish, T.M., Denslow, N.D., Blazer, V.S., Anderson, P.J., Coyle, J.J., Dethloff,
G.M. & Tillit, D.E. (2004). Biomonitoring of Environmental Status and Trends (BEST) Program:
Environmental Contaminants and their Effects on Fish in the Columbia River Basin. Scientific
Investigations Report 2004-5154: U.S. Geological Survey, Columbia Environmental Research
Center, Columbia, MO.
Merriam-Webster. (n.d.). Stope. In Merriam-Webster.com dictionary. Retrieved May 14, 2020, from
https://www.merriam-webster.com/dictionary/stope
Northwest Power and Conservation Council and Columbia River Toxics Reduction Working Group. (2018,
February 15). Polycyclic Aromatic Hydrocarbons: Locations in the Columbia River Basin Where
the Toxics Could Be Affecting Fish and Wildlife. Retrieved from Northwest Power and
Conservation Council website: https://app.nwcouncil.org/ext/maps/Contaminants/
Polansek, T. (2020, February 6). Corteva to stop making pesticide linked to kids' health problems. (D.
Gregorio, Ed.) Chicago, IL, USA. Retrieved from Reuters : https://www.reuters.com/article/us-
corteva-agriculture-pesticide/corteva-to-stop-making-pesticide-linked-to-kids-health-problems-
idUSKBN20023l
Rodenburg, L., Guo, J., & Christie, R. (2015). Polychlorinated biphenyls in pigments: inadvertent
production and environmental significance. Coloration Technology, 131(5), 353-369.
Toxic-Impaired Waterbodies on 303(d) Lists in the Columbia River Basin
49
------- |