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4vEPA Polychlorinated Biphenyl (PCB) Total Maximum
ggsa~» Daily Load (TMDL) Handbook
http://water.epa.gov/lawsregs/lawsguidance/cwa/tmdl/upload/pcb tmdl handbook.pdf
What are PCBs?
Polychlorinated biphenyls (PCBs) belong to a broad
family of organic chemicals. PCBs were manufactured
in the U.S. from 1929 until their manufacture was
banned in 1979. Although their uses in capacitors and
transformers for energy transmission are well known,
PCBs were also used in a wide variety of applications
such as paints, sealants, and building materials. PCBs
vary markedly in their chemical and physical properties,
and have a range of toxicity. Properties such as non-
flammability, low electrical conductivity, high thermal
stability, and high boiling point make PCBs highly stable
and persistent in the environment. PCBs tend to
bioaccumulate in living organisms.
What is the purpose of the PCB TMDL Handbook?
The purpose of the handbook is to provide EPA Regions, states, and other stakeholders with a
compendium of updated information for addressing Clean Water Act (CWA) section 303(d)
waters (http://water.epa.gov/lawsregs/lawsguidance/cwa/tmdl/intro.cfmtfsection303) impaired by
PCBs. This handbook identifies various approaches to developing PCB total maximum daily
loads (TMDLs) and provides examples of TMDLs from around the country, complete with Web
references. It aims to help states complete more PCB TMDLs, and ultimately restore those
waters impaired by PCBs.
How do PCBs rank nationally as a cause of water quality impairment?
6 5
Structure of Polychlorinated Biphenyl (PCB) Molecule
PCBs rank sixth among the national causes of water quality impairment in the country. PCBs
represent about eight percent of all causes of impairment nationally on CWA section 303(d) lists
(that is, of the more than 71,000 causes of impairment nationally, over 5,000 are PCB-related).
Of the more than 46,000 TMDLs in place nationally, about one percent (about 400 TMDLs)
address PCBs as a pollutant.
Causes of Impairment for 303(d) Listed Waters
Description of this table
NOTE: Click on a cause of impairment (e.g, pathogens) to see the specific state-reported causes that are grouped to make up this category, Click on the "Number of Causes of Impairment Reported" to see a
list of waters with that cause of impairment,
Cause of Impairment Group Name
Number of Causes of Impairment Reported
KetaIs i zither tha-i Menzur,1)
Organic Enrichment/Oxygen Depletion
Sediment
Polvchlor-inated Biohenvls CPCBs)
DH/Aciditv/Caustic Conditions
Causes of impairment are shown above in the Assessment, TMDL Tracking and Implementation System
(ATTAINS) (http://iaspub.epa.gov/waters10/attains nation cv.control?p report type=D November 18,
2011; this information is based on the most recent CWA section 303(d) and 305(b) data reported to the
EPA by states and available in ATTAINS.
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What is the scope of the handbook?
The handbook provides
an overview of PCBs
and water quality,
factors to consider in
early stages of TMDL
development, elements
of a TMDL, and an
appendix which includes
general PCB sources
and databases in which
to find information about
PCB sources. Each
section of the handbook
is complete with Web
references.
Table of Contents
Overview
ll. Factors to Consider in Early Stages of PCB TMDL Development
ill. Identification of Waterbodies, Pollutant Sources, Priority Ranking
IV. Water Quality Standards and TMDL Target
Loading Capacity - Linking Water Quality and Pollutant Sources
Vl. Linking Water Q uality and Pollutant Sources - Point Source Loadings
Vll. Linking Water Quality and Pollutant Sources-Nonpoint Source Loadings
VIII. WasteloadAllocationfWLA)
IX. Load Allocation (U\)
x. Margin of Safety (MOS)
XI. Critical Conditions and Seasonal Variation
Xll. Reasonable Assurance
XIII. Post-TMDLMonitoring
xiv. Implementation
Appendix: PCB Sources
For more information:
• Read the PCB TMDL Handbook at
http://water.epa.gov/lawsregs/lawsguidance/cwa/tmdl/upload/pcb tmdl handbook.pdf.
• Visit the Total Maximum Daily Loads (303d) Technical Support Documents website at
http://water.epa.gov/lawsregs/lawsguidance/cwa/tmdl/techsupp.cfm, which houses the
PCB TMDL Handbook and PCB TMDL fact sheets summarizing the elements of several
PCB TMDLs.
• Visit the Impaired Waters and Total Maximum Daily Loads Home Page at
http://water.epa.gov/lawsregs/lawsguidance/cwa/tmdl/index.cfm.
• Contact
U.S. Environmental Protection Agency
Office of Wetlands, Oceans and Watersheds
Watershed Branch (4503T)
1200 Pennsylvania Avenue, NW
Washington, DC 20460
Sarah Furtak at furtak.sarah@epa.gov or (202) 566-1167
December 2011, EPA 841-F-11-006
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