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Water: Total Maximum Daily Loads (303d)

Appendix G - Causes And Sources Of Pollution

Guidance for Water Quality-Based Decisions:
The TDML Process

Causes and Sources: Section 305(b) Waterbody System User's Guide, Third Edition (Version 2.0), August 1989, USEPA, Office of Water, Assessment and Watershed Protection Division, pages A-27 through A-31.

Causes Sources
Causes are the pollutants or conditions that are causing or expected to cause exceedances of water quality standards. One or more of the following categories should be used to identify causes of impairment: Sources are the point and nonpoint sources of the pollution categories that are listed as causes identified above. One or more of the following categories should be used to identify sources of impairment:
unknown toxicity organic enrichment/DO source unknown
pesticides salinity/TDS/chlorides industrial point sources municipal point sources
priority organics thermal modifications combined sewer overflow agriculture
nonpriority organics flow alterations silviculture construction
metals other habitat alterations urban runoff/storm sewers resource extraction
ammonia pathogens land disposal hydromodification
chlorine radiation habitat modification
other organics oil and grease Other categories:
nutrients taste and odor atmospheric deposition storage tank leaks
pH suspended solids highway maintenance/ runoff spills
siltation noxious aquatic plants in-place contaminants natural
filling and draining cause unknown recreational activities upstream impoundments


salt storage sites
Table of Contents Chapter 1 Chapter 2 Chapter 3
Chapter 4 Appendix A Appendix B Appendix C
apd ape apf apg
acro sections

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