Encyclopedia of Environmental Science and Engineering, Volume I and II

(Ben Green) #1

ENVIRONMENTAL HEALTH 343


TABLE 3 (continued)
Surface water criteria for public water supplies
DDTa 0.042 do
Dieldrina 0.017 do
Endrina 0.001 do
Heptachlora 0.018 do
Heptachlor epoxidea 0.018 do
Lindanea 0.056 do
Methoxychlora 0.035 do
Organic phosphates 0.1c do
plus carbamatesa
Toxaphenea 0.005 do
Herbicides:
2, 4-D plus 2, 4, 5-T,
plus 2, 4, 5-TPa

0.1 do

Phenolsa 0.001 do
Radio activity: (pc/1) (pc/1)
Gross betaa 1000  100
Radium-226a 3  1
Strontium-90a 10  2

a The defi ned treatment process has little effect on this constituent.
(Coagulation, sedimentation, paid rapid fi ltration and chlorination.)
+ No concensus on a single numerical value which is applicable throughout
the country. See reference.
b Microbiological limits are monthly arithmetic averages based upon an
adequate number of samples. Total coliform limit may be relaxed if fecal
coliform concentration does not exceed the specifi ed limit.
c As parathion in cholinesterase inhibition. It may be necessary to resort to
even lower concentrations for some compounds or mixtures. (Permissible
levels are based upon the recommendations of the Public Health Service
Advisory Committee on Use of the PHS Drinking Water Standards.)
From Water Quality Criteria, Report of the National Advisory Committee to
the Secretary of the Interior, April 1, 1968, Washington, DC, p. 20.

TABLE 3
Surface water criteria for public water supplies

Constituent or characteristic Permissible criteria Desirable criteria

Organic chemicals:
Color (color units) 75  10
Odor  Virtually absent
Temperaturea do 
Turbidity do Virtually absent
Microbiological:
Coliform organisms 10,000/100 mlb 100/100 mlb
Fecal coliforms 2000/100 mlb 20/100 mlb
Inorganic chemicals: (mg/l) (mg/l)
Alkalinity 
Ammonia 0.5 (as N) 0.01
Arsenica 0.05 Absent
Bariuma 1.0 do
Borona 1.0 do
Cadmiuma 0.01 do
Chloridea 250  25
Chromium,a
hexavalent 0.05 Absent
Coppera 1.0 Virtually absent
Dissolved oxygen ³4 (monthly mean) Near saturation
³3 (individual sample)
Fluoridea 
Hardnessa do do
Iron (fi lterable) 0.3 Virtually absent
Leada 0.05 Absent
Manganesea
(fi lterable) 0.05 do
Nitrates plus nitritesa 10 (as N) Virtually absent
pH (range) 6.0-8.5 
Phosphorusa  do
Seleniuma 0.01 Absent
Silvera 0.05 do
Sulfatea 250  50
Total dissolved solidsa 500  200
(fi lterable residue)
Uranyl iona 5 Absent
Zinca 5 Virtually absent
Organic chemicals:
Carbon chloroform 0.15 0.04
extracta (CCE)
Cyanidea 0.20 Absent
Methylene blue active 0.5 Virtually absent
substancesa
Oil and greasea Virtually absent Absent
Pesticides:
Aldrina 0.017 do
Chlordanea 0.003 do

(continued)

manganese (90), fl uoride (52), sulfate (25), nitrate (19). The
study also showed that 56% of the systems were defi cient
in one or more of the following: source protection; disin-
fection or control of disinfection; clarifi cation (removal of
suspended matter) or control of clarifi cation; and pressure in
the distribution system. It was also reported that 90% of the
systems did not have suffi cient samples collected for bacte-
riological surveillance; 56% of the systems had not been sur-
veyed by the state or local health department within the last
three years; in 54%, cross-connection prevention ordinances
were lacking; in 89%, reinspection of existing construction
was lacking; in 61%, the operators had not received any
water treatment training; in 77%, the operators were defi -
cient in training for microbiological work and 46% of those
who needed chemistry training did not have any. Finally, the
smaller communities had more water quality problems and
defi ciencies than the larger ones, showing the advisability of
consolidation and regionalization where this is feasible.

Water Cycle

The movement of water from the atmosphere to the earth and
back again to the atmosphere can be best illustrated by the

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