Current through Register Vol. 18, September 20, 2024
(1) A
supplier of water shall collect water samples taken from each entry point location
serving a community and nontransient noncommunity public water supply system for
analysis by an approved laboratory of the following inorganic chemicals:
(a) alkalinity total
(b) calcium
(c) pH value
(d) sodium
(e) iron
(f) manganese
(g) hardness
(h) specific conductance
(i) sulphate
(j) chloride
(k) magnesium
(2) Samples required in (1) must be collected and
analyzed at the frequency for regulated inorganic chemicals, other than nitrate and
nitrite, as required in (3). The department may waive the sampling and analysis
requirement for any or all of these chemicals if the results of at least one sample
demonstrate that further sampling is unnecessary.
(3) The department adopts and incorporates by
reference the following monitoring and analytical requirements:
(a)
40 CFR
141.23, which sets forth sampling and analytical
method requirements for inorganic chemicals except that 141.23(i) is replaced with
the following:
"(i) Compliance with
40 CFR
141.11 or
141.62(b) (as
appropriate) shall be determined based on the analytical result(s) obtained at each
sampling point.
(1) For systems monitoring more
than once per year, compliance with the maximum contaminant levels, as described in
40 CFR
141.11 or
141.62(b), for
fluoride, asbestos, barium, cadmium, chromium, mercury, selenium, antimony,
beryllium, cyanide, nickel, thallium, or arsenic is determined by a running annual
average at any sampling point.
(2) For
systems monitoring annually or less frequently for fluoride, asbestos, barium,
cadmium, chromium, mercury, selenium, antimony, beryllium, cyanide, nickel,
thallium, or arsenic whose sample result(s) exceed(s) a maximum contaminant level,
as described in 40 CFR
141.11 or
141.62(b), must begin
quarterly sampling. The system will not be considered in violation of the maximum
contaminant level until it has completed one year of quarterly sampling.
(3) If any sample result will cause the running
annual average to exceed the maximum contaminant level at the sampling point, the
system will be considered out of compliance with the maximum contaminant level
immediately.
(4) If a system fails to
collect the required number of samples, compliance will be based on the total number
of samples collected.
(5) If any sample
result is less than the detection limit, zero will be used to calculate the annual
average.
(6) Compliance with the maximum
contaminant levels for nitrate and nitrite is determined based on one sample if the
levels of these contaminants are below the MCLs. If the levels of nitrate and/or
nitrite exceed the MCLs in the initial sample, a confirmation sample is required in
accordance with paragraph (f)(2) of this section, and compliance shall be determined
based on the average of the initial and confirmation samples.
(7) Arsenic sampling results will be reported to
the nearest 0.001mg/L."
(b)
40 CFR
141.24, which sets forth sampling and analytical
method requirements for organic chemicals other than total
trihalomethanes;
(c)
40 CFR
141.25, which sets forth analytical method
requirements for radioactive contaminants;
(d)
40 CFR
141.26, which sets forth sampling requirements for
radioactive contaminants in community water systems;
(e) CFR 141.27, which sets forth requirements for
alternate analytical methods;
(f)
40 CFR
141.28, which sets forth requirements for the use
of certified laboratories by public water system suppliers and by the department,
except that, for the purpose of this subchapter, the phrase "certified laboratory"
means "approved laboratory" as defined in ARM
17.38.202. References to
40 CFR
141.21 in
40 CFR
141.28 also refer to ARM
17.38.215;
(g)
40 CFR
141.29, which sets forth sampling requirements for
consecutive public water systems;
(h)
40 CFR
141.40, which sets forth special sampling and
analytical method requirements for unregulated inorganic and organic
contaminants;
(i)
40 CFR
141.41, which sets forth special monitoring and
analytical method requirements for sodium;
(j)
40 CFR
141.42, which sets forth special requirements for
water system materials subject to corrosion;
(k)
40 CFR
141.80, which sets forth general requirements for
the control of lead and copper;
(l)
40 CFR
141.86, which sets forth sampling and analytical
method requirements for lead and copper;
(m)
40 CFR
141.87, which sets forth sampling requirements for
water quality parameters;
(n)
40 CFR
141.88, which sets forth sampling requirements for
lead and copper in source water;
(o)
40 CFR
141.89, which sets forth analytical method
requirements for lead, copper, and water quality parameters;
(p)
40 CFR
141.130, whichsets forth general requirements for
control of disinfectants and disinfection byproducts;
(q)
40 CFR
141.131, which sets forth analytical method
requirements for disinfectants and disinfection byproducts;
(r)
40 CFR
141.132, which sets forth sampling requirements
for disinfectants and disinfection byproducts; and
(s)
40 CFR
141.133, which sets forth compliance requirements
for disinfectants and disinfection byproducts.
(4) A supplier shall sample every new source of
water supply, both surface and ground, for nitrate and nitrite analyses to
demonstrate compliance with this subchapter before the water is served to the
public. Unless otherwise directed by the department, a supplier also shall sample
all new sources of water supply for analysis of the parameters identified in (3)
before the end of the calendar quarter in which the source is connected to a public
water supply. A supplier shall also sample a new source serving a transient
non-community water system for either total dissolved solids (TDS) or specific
conductance.
(5) Further sampling or
corrective action may be required by the department if the results of the analyses
do not demonstrate conformance with applicable maximum contaminant levels or actions
levels.
