Environmental Planning and Management by John H Baldwin

Author:John H Baldwin [Baldwin, John H]
Language: eng
Format: epub
Tags: Public Policy, Environmental Policy, Political Science, General
ISBN: 9780429709210
Google: zKqbDwAAQBAJ
Goodreads: 51802447
Publisher: Routledge
Published: 2019-06-04T00:00:00+00:00

metals, petroleum, bacteria, and nitrate and phosphate nutrients. In rural areas the most widespread source of nonpoint pollution is agricultural runoff, which can contain pesticides, fertilizers, oxygen demanding wastes, pathogens, and dissolved solids (CEQ, 1980).

Sedimentation from topsoil erosion is the largest source of water pollution in the United States. Sediment from nonpoint sources contributes more than 360 times the quantity discharged from industrial and municipal point sources after treatment. Between 1.8 billion and 4.0 billion tons of sediment are washed into U.S. waterways annually, with more than half contributed by agriculture. In the past two centuries, nearly one-third of all agricultural topsoil in the United States has been lost to erosion (CEQ, 1976 and 1980; Miller, 1979; Pimentel et al., 1976). In addition, nitrate, phosphate, and oxygen-demanding wastes

Table 6-8. Thresholds Used in the CEQ Analysis of National Surface Water Quality (CEQ, 1980; EPA, 1976b).

Pollution Indicator Symbol EPA threshold level

Fecal collform bacteria FC 200 cells/100 ml a

Total phosphorus TP 0.1 mg/l b

Dissolved oxygen DO 5.0 mg/l c

Total cadmium Cd 4.0 μg/l for soft water d

10.0 μg/l for hard water e

Total lead Pb exp [(1.51 In (hardness) — 3.37)] f

Total mercury Hg 0.05 μg/l g

l = liter; ml = milliliter; mg = milligram; μg = microgram. a EPA criteria level for “bathing waters.” There is no uniform national standard for FC concentrations in water used for swimming; standards vary with use and locality. State standards sometimes differ from nationally recommended criteria.

b Value discussed by EPA for “prevention of plant nuisances in streams or other flowing waters not discharging directly to lakes or impoundments.”

c EPA criteria level for “good fish populations.”

d EPA criteria level for preservation of aquatic life less sensitive than cladocerans and salmonid fishes for water with CaCO3 concentrations of up to 75 mg/l.

e Because the EPA Redbook criteria level for preservation of the less sensitive aquatic life for water with over 75 mg/l CaCO3 concentration Is 12 μg/l, CEQ has chosen to use the more stringent criteria level “for domestic water supply (health).”

f A 1979 EPA proposed criteria level for preservation of aquatic life.

g EPA criteria level for preservation of “freshwater aquatic life and wildlife.”

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