Page 68 - Fundamentals of Water Treatment Unit Processes : Physical, Chemical, and Biological

Water Contaminants 23

TABLE 2.1
Proposed Discharge Limitations to Illustrate a Variety of Contaminants and Maximum
Concentrations for an Industrial Discharge
Discharge to POTW a Discharge to River b
Monthly Average Daily Maximum Monthly Average Daily Maximum
Parameter (mg=L) (mg=L) (mg=L) (mg=L)
Anthracene 14 36 11 30
Benzene 33 80 19 70
Chlorobenzene 74 197 8 14
Chloroform 62 176 11 24
Ethylbenzene 108 290 17 56
Toluene 18 45 13 41
trans-1,2-Dichloroethene 19 50 11 28
Tetrachloroethene 40 125 11 29
Trichloroethylene 20 53 11 28
1,1,1-Trichloroethane 17 45 11 28
Methylene chloride 63 241 21 46
1,2-Dichlorobenzene 105 410 40 84
1,3-Dichlorobenzene 108 290 16 23
1,4-Dichlorobenzene 73 194 8 14
Bis(2-ethylhexyl) 72 197 53 144
phthalate
Naphthalene 14 36 11 30
Nitrobenzene 1704 4878 14 35
Phenol 14 34 8 13
1,2,4-Trichlorobenzene 109 415 35 72
1,1-Dichloroethene 17 46 8 13
1,2-Dichlorpropane 149 605 79 119
2,4-Dimethylphenol 14 36 9 19
4,6-Dinitro-o-cresol 59 211 37 63
Di-n-butyl phthalate 15 33 14 29
Cadmium 130 130 5 11
Chromium, total 120 230 573 1430
Chromium, hexavalent 60 110 132 266
Copper 110 110 <dL <dL
Lead 400 400 <dL <dL
Mercury 5 5 0.2 0.5
Nickel 170 360 872 2054
Zinc 490 490 <dL <dL
Arsenic 50 50 2 4
BOD5 No limits 45 120
TSS No limits 183 57
pH (standard units) 6 10 6 9
Source: Adapted from Cooper, A.M. et al., Environ. Prog., 11(1), 18, February 1992.
a
Pretreatment limitations to POTW (publicly owned treatment works, per PL92-500, the 1972 Clean Water Act).
b
Direct discharge limitations.

In 1965, PL89-234 required that states develop standards which was the first federal mandate for states to develop
for interstate streams. In 1972, pursuant to PL92-500—the drinking water standards. By 1986, some 83 contaminants
Clean Water Act—an effluent discharge permit was required were regulated. Regulation of toxic pollutants was required
and was called the National Pollution Discharge Elimination under the 1972 Clean Water Act (PL92-500), resulting in the
System (NPDES) permit. Drinking water standards were ‘‘priority pollutant’’ list with some 129 contaminants (Keith
required by PL93-523—the Safe Drinking Water Act— and Telliard, 1979). In addition, standards have evolved, or