Current through Bulletin 2024-18, September 15, 2024
Community, non-transient non-community, and transient
non-community water systems shall conduct monitoring as specified to determine
compliance with the maximum contaminant levels specified in
R309-200-5 in accordance with this section.
(1)
Monitoring shall be conducted as follows:
(a)
Groundwater systems shall take a minimum of one sample at every entry point to
the distribution system which is representative of each well after treatment
(hereafter called a sampling point) beginning in the compliance period starting
January 1, 1993. The system shall take each sample at the same sampling point
unless conditions make another sampling point more representative of each
source or treatment plant.
(b)
Surface water systems shall take a minimum of one sample at every entry point
to the distribution system after any application of treatment or in the
distribution system at a point which is representative of each source after
treatment (hereafter called a sampling point) beginning in the compliance
period beginning January 1, 1993. The system shall take each sample at the same
sampling point unless conditions make another sampling point more
representative of each source or treatment plant. (Note: For purposes of this
paragraph, surface water systems include systems with a combination of surface
and ground sources.)
(c) If a
system draws water from more than one source and the sources are combined
before distribution, the system shall sample at an entry point to the
distribution system during periods of normal operating conditions (i.e., when
water is representative of all sources being used).
(d) The frequency of monitoring for asbestos
shall be in accordance with R309-205-5(2); the frequency of monitoring for
antimony, arsenic, barium, beryllium, cadmium, chromium, cyanide, fluoride,
mercury, nickel, selenium, sodium, sulfate, thallium, and total dissolved
solids shall be in accordance with R309-205-5(3); the frequency of monitoring
for nitrate shall be in accordance with R309-205-5(4); the frequency of
monitoring for nitrite shall be in accordance with R309-205-5(5).
(e) Confirmation samples:
(i) Where the results of sampling for
antimony, arsenic, asbestos, barium, beryllium, cadmium, chromium, cyanide,
fluoride, mercury, nickel, selenium, sulfate, thallium or total dissolved
solids indicate an exceedance of the maximum contaminant level, the Director
may require that one additional sample be collected as soon as possible after
the initial sample was taken (but not to exceed two weeks) at the same sampling
point.
(ii) Where nitrate or
nitrite sampling results indicate an exceedance of the maximum contaminant
level, the system shall take a confirmation sample within 24 hours of the
system's receipt of notification of the analytical results of the first sample.
Systems unable to comply with the 24-hour sampling requirement shall
immediately notify the consumers in the area served by the public water system
source in accordance with
R309-220-5.
Systems exercising this option shall take and analyze a confirmation sample
within two weeks of notification of the analytical results of the first
sample.
(iii) Procedures if the
Secondary Standard for Fluoride is Exceeded Notification of State and/or
Public.
If the result of an analysis indicates that the level of
fluoride exceeds the Secondary Drinking Water Standard, the supplier of water
shall give notice as required in
R309-220-11.
(iv) The results of the initial
and confirmation sample(s) taken for any contaminant, shall be averaged. The
resulting average shall be used to determine the system's compliance in
accordance with paragraph (1)(g) of this section. The Director has the
discretion to delete results of obvious sampling errors.
(f) The Director may require more frequent
monitoring than specified in paragraphs (2), (3), (4) and (5) of this section
or may require confirmation samples for positive and negative results. The
Director may also require an appropriate treatment process.
(g) Compliance with
R309-200-5(1)
shall be determined based on the analytical result(s) obtained at each sampling
point.
(i) For systems which are conducting
monitoring at a frequency greater than annual, compliance with the maximum
contaminant levels for antimony, arsenic, asbestos, barium, beryllium, cadmium,
chromium, cyanide, fluoride, mercury, nickel, selenium, sulfate, thallium and
total dissolved solids is determined by a running annual average at each
sampling point. If the average at any sampling point is greater than the MCL,
then the system is out of compliance. If any one sample would cause the annual
average to be exceeded, then the system is out of compliance immediately. Any
sample below the method detection limit shall be calculated at zero for the
purpose of determining the annual average. If a system fails to collect the
required number of samples, compliance (average concentration) shall be based
on the total number of samples collected.
(ii) For systems which are monitoring
annually, or less frequently, the system is out of compliance with the maximum
contaminant levels for antimony, arsenic, asbestos, barium, beryllium, cadmium,
chromium, cyanide, fluoride, mercury, nickel, selenium, sulfate, thallium and
total dissolved solids if the level of a contaminant at any sampling point is
greater than the MCL. If confirmation samples are required by the Director, the
determination of compliance will be based on the annual average of the initial
MCL exceedance and any Director required confirmation samples. If a system
fails to collect the required number of samples, compliance (average
concentration) shall be based on the total number of samples collected. If the
average of the samples exceed the maximum contaminant levels then the water
system shall provide public notice as required under R309-220.
(iii) Compliance with the maximum contaminant
levels for nitrate and nitrite is determined based on one sample. If the levels
of nitrate and/or nitrite exceed the MCLs in the initial sample, a confirmation
sample is required in accordance with paragraph (1)(g)(ii) of this section, and
compliance shall be determined based on the average of the initial and
confirmation samples.
(iv) If a
public water system has a distribution system separable from other parts of the
distribution system with no interconnections, the Director may allow the system
to give public notice to only the area served by that portion of the system
which is out of compliance.
(h) Each public water system shall monitor at
the time designated by the Director during each compliance period.
(2) The frequency of monitoring
conducted to determine compliance with the maximum contaminant level for
asbestos specified in
R309-200-5(1)
shall be conducted as follows:
(a) Each
community and non-transient non-community water system is required to monitor
for asbestos during the first three-year compliance period of each nine-year
compliance cycle beginning in the compliance period starting January 1,
1993.
(b) If the system believes it
is not vulnerable to asbestos contamination in its source water, it may apply
to the Director for a waiver of the monitoring requirement in paragraph (a) of
this section. If the Director grants the waiver, the system is not required to
monitor for asbestos.
(c) The
Director may grant a waiver based on a consideration of the potential asbestos
contamination of the water source.
(d) A waiver remains in effect until the
completion of the three-year compliance period. Systems not receiving a waiver
shall monitor in accordance with the provisions of paragraph (a) of this
section.
(e) A system vulnerable to
asbestos contamination due solely to source water shall monitor in accordance
with the provision of R309-205-5(1).
(f) A system vulnerable to asbestos
contamination due both to its source water supply and corrosion of
asbestos-cement pipe as specified in
R309-210-7 shall take one sample at a tap served by asbestos-cement pipe and under
conditions where asbestos contamination is most likely to occur.
(g) A system which exceeds the maximum
contaminant levels as determined in R309-205-5(1)(g) shall monitor quarterly
beginning in the next quarter after the violation occurred.
(h) The Director may decrease the quarterly
monitoring requirement to the frequency specified in paragraph (a) of this
section provided the Director has determined that the system is reliably and
consistently below the maximum contaminant level. In no case can the Director
make this determination unless a groundwater system takes a minimum of two
quarterly samples and a surface (or combined surface/ground) water system takes
a minimum of four quarterly samples.
(i) If monitoring data collected after
January 1, 1990 are generally consistent with the requirements of
R309-205-5(2), then the Director may allow systems to use that data to satisfy
the monitoring requirement for the initial compliance period beginning January
1, 1993.
(3) The
frequency of monitoring conducted to determine compliance with the maximum
contaminant levels in
R309-200-5(1).
for antimony, arsenic, barium, beryllium, cadmium, chromium, cyanide, fluoride,
mercury, nickel, selenium, sodium, sulfate, thallium and total dissolved solids
shall be as follows:
(a) Each community and
non-transient non-community groundwater system shall take one sample at each
sampling point once every three years. Each community and non-transient
non-community surface water system (or combined surface/ground) shall take one
sample annually at each sampling point. Each transient non-community system
shall take one sample for sulfate only at each sampling point once every three
years for both groundwater and surface water systems.
(b) The system may apply to the Director for
a waiver from the monitoring frequencies specified in paragraph (3)(a) of this
section.
(c) A condition of the
waiver shall require that a system shall take a minimum of one sample while the
waiver is effective. The term during which the waiver is effective shall not
exceed one compliance cycle (i.e., nine years).
(d) The Director may grant a waiver provided
surface water systems have monitored annually for at least three years and
groundwater systems have conducted a minimum of three rounds of monitoring. (At
least one sample shall have been taken since January 1, 1990.) Both surface and
groundwater systems shall demonstrate that all previous analytical results were
less than the maximum contaminant level. Systems that use a new water source
are not eligible for a waiver until three rounds of monitoring from the new
source have been completed.
(e) In
determining the appropriate reduced monitoring frequency, the Director shall
consider:
(i) Reported concentrations from
all previous monitoring;
(ii) The
degree of variation in reported concentrations; and
(iii) Other factors which may affect
contaminant concentrations such as changes in groundwater pumping rates,
changes in the system's configuration, changes in the system's operating
procedures, or changes in stream flows or characteristics.
(f) A decision by the Director to grant a
waiver shall be made in writing and shall set forth the basis for the
determination. The determination may be initiated by the Director or upon an
application by the public water system. The public water system shall specify
the basis for its request. The Director shall review and, where appropriate,
revise its determination of the appropriate monitoring frequency when the
system submits new monitoring data or when other data relevant to the system's
appropriate monitoring frequency become available.
(g) Systems which exceed the maximum
contaminant levels as calculated in R309-205-5(1)(g) of this section shall
monitor quarterly beginning in the next quarter after the violation
occurred.
(h) The Director may
decrease the quarterly monitoring requirement to the frequencies specified in
paragraphs (3)(a) and (b) of this section provided it has determined that the
system is reliably and consistently below the maximum contaminant level. In no
case can the Director make this determination unless a groundwater system takes
a minimum of two quarterly samples and a surface water system takes a minimum
of four quarterly samples.
(4) All public water systems (community;
non-transient non-community; and transient non-community systems) shall monitor
to determine compliance with the maximum contaminant level for nitrate in
R309-200-5(1).
(a) Community and non-transient non-community
water systems served by groundwater systems shall monitor annually beginning
January 1, 1993; systems served by surface water shall monitor quarterly
beginning January 1, 1993.
(b) For
community and non-transient non-community water systems, the repeat monitoring
frequency for ground water systems shall be quarterly for at least one year
following any one sample in which the concentration is greater than or equal to
50 percent of the MCL. The Director may allow a groundwater system to reduce
the sampling frequency to annually after four consecutive quarterly samples are
reliably and consistently less than the MCL.
(c) For community and non-transient
non-community water systems, the Director may allow a surface water system to
reduce the sampling frequency to annually if all analytical results from four
consecutive quarters are less than 50 percent of the MCL. A surface water
system shall return to quarterly monitoring if any one sample is greater than
or equal to 50 percent of the MCL.
(d) Each transient non-community water system
shall monitor annually beginning January 1, 1993.
(e) After the initial round of quarterly
sampling is completed, each community and non-transient non- community system
which is monitoring annually shall take subsequent samples during the
quarter(s) which previously resulted in the highest analytical
result.
(5) All public
water systems (community; non-transient non-community; and transient
non-community systems) shall monitor to determine compliance with the maximum
contaminant level for nitrite in
R309-200-5(1).
(a) All public water systems shall take one
sample at each sampling point in the compliance period beginning January 1,
1993 and ending December 31, 1995.
(b) After the initial sample, systems where
an analytical result for nitrite is less than 50 percent of the MCL shall
monitor at the frequency specified by the Director.
(c) For community, non-transient
non-community, and transient non-community water systems, the repeat monitoring
frequency for any water system shall be quarterly for at least one year
following any one sample in which the concentration is greater than or equal to
50 percent of the MCL. The Director may allow a system to reduce the sampling
frequency to annually after determining the system is reliably and consistently
less than the MCL.
(d) Systems
which are monitoring annually shall take each subsequent sample during the
quarter(s) which previously resulted in the highest analytical
result.