11905
PROPOSED RULES
responding concentration
_ shall not be cxeeeded:
Temprrat vito
din Fe)
of
(c°)
fluoride
Level (mp/t)
we
‘Ye
SOOO RT eee
NUS fo
SLO
9 10
TOT (0
TIS 10
ral
‘Sc
of
if
ice
$8.9,
ASL,
TH...
70.2
00 5
di)
The maximum contaminant level for
the total concentration of organic chem-:
icals, as determined by the carbon chlo-
roform extract method
§ 141.24¢b), Is 0.7 mg/l.
set
forth
nents.
: the
fn
membrane
filter
technique.
The
examined per month; or
(B) Three or more portions {mn more ; Samples shall be taken at points which
j arc representative of the conditions
than five percent of the sampics if 20 or}
§ 141.13 Maximum contaminant levels”
moro samples are examined per month. | within the distribution system.
‘for pesticides.
’
(b) The supplier of water shall take
(ii) When the supplier of water emThe following are the maximum conploys the fermentation tube method and ; coliform density samples at regular intaminant levels for pesticides:
100 milliliter standard portions pursu- tervals throughout the month, and in
(a) Chlorinated Hydrocarbons:
‘ ant to § 141.21(a) coliforms shall not be: number proportionate to the population
Level mg/l present in more than 60 percent of the} served by the public water system. In no
in any month; and either
event shall the frequency be less than as
Chlordane (cis and trans) (1,2.4.5,: portions
(A) Five or more portions in more
6,7,8,8 “- Octachloro - 3n,4,5,7a:
set forth below:
tetrahydro-4,7-methanoindan) - 0.003 - than one sample when less than five!
Minimum number of
Endrin (1,2,3,4,10,10 - Hexachloro; samples . are cxamined; or.
.
Population served:
Samples per month
(B) Five or more portions in more
25 to 2.500
2
6,7 - epoxy - 1,4,49,5,6.7,8,8a-
the
ion
ny
ori-
the
Adion
ny
slic
octahydro-1,4-endo,
endo-5,8-
,
iter
ply
ate,
aDp-
and
any
but
blic
ions
son;
2as-
\ five samples or more are examined.
i
(b) The supplier of water shall pro-{
4
ft
vide water in which there shall be no
5} greater than 500 organisms per one mil-
Heptachlor
(1,4,5,6,7,.8,8-He p tachloro-30,4,7,7a-tetrahydro
4,7methnnoindene) ..----.----. 2.
Heptochlor Epoxtde (1.4,5,6,7,8,8Heptachloro - 2,3-cpoxy-3n.4,7,7a~
tetrahydro-4,7-methanoindan) .
Lindane (1,2,3,4,5,6-Hexachlorocyclohexane, gamma tsomer) -.-Methoxychior (1,1,1-Trichloro-2,2bis (p-methoxyphenyl| cthane)_ 0.1
Toxaphene
(O,,#£,,01,—Technical
chlorinated campheno, 67-69%
ehiorine) .---.-.-----..------- 0.005
(b) Chlorophenoxys: ©
2.4-D
(2,4-Dichlordphenoxyacetic
:
acid) .. 2-21 oe ee eee 0.1
2,4,5-TP
Silvex
(2,4,5-Trichlorophenoxyproplonic acid) ~--...... 0.01
-yels
§ 141.14 Maximum
of turbidity.
jum
em-
The maximum contaminant level of
turbidity in the drinking water at a representative entry point(s) to the distribution system is one turbidity unit (TU),
as determined pursuant to § 141.22, except that five or fewer turbidity units
evel
too
ya ~
o
Nn
a
ne
_o
°o
a
g/l)
> the
sys-
cor-
contaminant
level
may be allowed If the supplier of water
can demonstrate to the State that the
higher turbidity does not:
. (3) Interfere with disinfection;
(b) Prevent maintenance of an effective disinfectant agent throughout the
distribution system; and
(c) Interfere
with
microbiological
determinations.
:
§ 141.15 Maximum microbiological contaminant levels.
.(a) The supplier of water may employ one of two methods to determine
compliance with the coliform maximum
contaminant levels.
ys
rorzgte
,
than 20 percent of the samples when
Il
dimethnano naphthalene) -_.__-.
wwronwwwr en:
gea°¢ge
100 milliliters in more }t
(a) The supplier of water shall mace
coliform density measurements, for tne
(2) (1) When the suppier of water em- | purpose of determining compliance with
§ 141.15, in accordance with the anatytiploys the fermentation tubo method ana
cal
recommendations
set
forth
in
10 milliliter standard portions pursuant
: “Standard Methods for the Examination
to § 141.21, coliforms shall not be present in more than 10 percent of the por- , of Water and Wastewater.” American’
! Public Health Association, 13th Edition,
tions in any month; and cither
(A) Three or more portions in one i pp 662-688, except that only a 100 millisample when less than 20 samples are;; liter sample size shall be employed in
§ 141.22 Maximunt contaminant levels:
for organic chemicals.
:
on
tor
in
(2)
ige
ich
ith
Four per
than five percent of the standard samples when 20 or more are examined per
month.
serving only educational tnstitulions.
als
ne
{§ 142.21. When the supplier of water ex-
the membrane filter technique ,ercises the option provided by this para\ purstant to § 141.21(a) the coliform {graph (b) he shall maintain no less than
+ 0.3 mg/l free chlorine in the public water
\ densities shall not exeeed c one per 100 distribution system, Menasuremenis saau
milliliters as the arithmeti mean of all
i samples examined per month; andeither be made in accordance with “Standard
() Four per 100 milliliters In more ; Methods," 13th td., pp 129-132.
tI
: than one standard sample when less '§ 3412)
Microbiologie!
contaminant
> than 20 are examined per month: or
t
sampling and analytical require-
The requirements of this pararraph (b)
ido hot apply to public water supplies»
ore
When the supplicr of water em-
(1)
t
I ploys
i
: iter as determined by the standard
! bacterial plate count provided in
3 141.21(f).
§ 141.16 Substitution of residual chlo.
rine measurement for total coliform
2.501 to 3,300......-.... 0
3
4,101 to 4,900___.-__.___
4,901 to 5,800___.-.-_-----...2-.2-.-5,801 to 6,700._---.- 2...
5
€
7
3.301 to 4.100...------- Reeenennes
6,701 to 7,600. _.-----.--------a eot ° Bao0noneee
8,401 to 10,300_.._-10,301 to
4
8
i
1
12
to bol ee
13
(a) The supplier of water may, with
13,701 to
16
use of chlorine residual ménitoring for
15.501 to
required to be taken by § 141.21 (b), pro-
18.101 to
micasurement. 4
‘the approval of the State, substitute the
not more than 75 percent of the samples
vided that the supplier
chlorine residual samples
are representative of
within the distribution
of water takes
at points which
the conditions
system at the
frequency of at least four for cach sub-
stituted microbiological sample. There
shall be at least daily determinations of
chlorine residual. Measurements shall be
made in accordance with “Standard
Methods,” 13th Ed., pp 129-132. When
12.901 to
14,601 to
}6:007 [©
18.901
19,801
20,701
21,501
to
to
to
to
22,301 to
18
3
21
22
23
24
25
26
27
an
33,001 to 37,000
40
25,001 to 28.000
28,001 to 33.000
37.001 to 41,000
41,001 to 46,000
46,001 to 50,000
4900 or fewer persons, the supplier may,
_.__..
70,001 to 76.000 _......
with the approval of the State, make a
total substitution of chlorine residual
measurement for the samples required to
17
oar a 2
oa oot te 95'000
the supplier af water exercises the option provided in this paragraph (1), he
shall maintain no less than 0.2 mg/1 free
chlorine in the public water distribution
sysrem.
.
.
) For public water systems serving
13
89.001 10 54.000
59,001
to 64,000
64.001 to 70,000
76,001 to 83,000
83,001 to 90,000
90,001 to 96,000
30
35
45
50
55
so
70
15
20
85
90
95
be taken by § 141.21(b): Provided, That
pooor to 1008wnnnnn ee
sentative of the conditions within the
distribution system at the rate of one
igg‘o901 to 220:000_................ ne
929.001 to 280000...
-* 350
the supplier of water takes chlorine residual samples at points which are repre-
per day for each microbiological sample
required to be ‘taken. per month-under
.
0 T8000 — =
tee'pot * ioe pone
-- 109
-ceceen u
250,001 to 290,000...
--- 169
290,001 to 320,000__...-..--_-..---- n- 170
FEDERAL REGISTER, VOL. 40, NO. 51—FRIDAY, MARCH 14, 1975
18410