Indiana Administrative Code
Title 327 - WATER POLLUTION CONTROL DIVISION
Article 8 - PUBLIC WATER SUPPLY
Rule 2 - Drinking Water Standards
Section 2-4.1 - Collection of samples for inorganic chemical testing
Universal Citation: 327 IN Admin Code 2-4.1
Current through September 18, 2024
Authority: IC 13-13-5; IC 13-14-8-7; IC 13-14-9; IC 13-18-3; IC 13-18-16
Affected: IC 13-18
Sec. 4.1.
(a) CWSs shall conduct monitoring to determine compliance with the MCLs specified in section 4(a), 4(c), and 4(d) of this rule in accordance with this section. NTNCWSs shall conduct monitoring to determine compliance with the MCLs specified in section 4(a) and 4(d) of this rule in accordance with this section. TWSs shall conduct monitoring to determine compliance with the MCLs specified in section 4(a) of this rule in accordance with this section.
(b) When a contaminant listed in section 4 of this rule exceeds the MCL, the supplier of water shall report to the commissioner under section 13 of this rule and shall give notice to the public under 327 IAC 8-2.1-7 through 327 IAC 8-2.1-16. Monitoring after public notification shall be at a frequency designated by the commissioner and shall continue until the MCL has not been exceeded in two (2) successive samples or until a monitoring schedule as a condition to an enforcement action shall become effective.
(c) Monitoring shall be conducted as follows:
(1) Ground water
systems shall take a minimum of one (1) sample at every entry point to the
distribution system that 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.
(2)
Surface water systems, including systems with a combination of surface and
ground sources, shall take a minimum of one (1) sample at every entry point to
the distribution system after any application of treatment or in the
distribution system at a point that 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.
(3) If a system draws water from more than
one (1) source and the sources are combined before distribution, the system
must sample at an entry point to the distribution system during periods of
normal operating conditions, for example, when water is representative of all
sources being used.
(4) The
commissioner may reduce the total number of samples that must be analyzed by
allowing the use of compositing. Composite samples from a maximum of five (5)
samples are allowed, provided that the detection limit of the method used for
analysis is less than one-fifth (1/5) of the MCL.
Compositing of samples must be completed in the laboratory as follows:
(A) When a composite sample is analyzed, if
the concentration in the composite sample is greater than or equal to one-fifth
(1/5) of the MCL of any inorganic chemical, then a
follow-up sample must be analyzed within fourteen (14) days at each sampling
point included in the composite. These samples must be analyzed for the
contaminants that exceeded one-fifth (1/5) of the
MCL in the composite sample. Detection limits for each analytical method and
MCLs for each inorganic contaminant are the following:
| Contaminant | MCL (mg/l) | Methodology | Detection Limit (mg/l) |
| Antimony | 0.006 | Atomic absorption; furnace | 0.003 |
| Atomic absorption; platform | 0.00085 | ||
| ICP-mass spectrometry | 0.0004 | ||
| Hydride-atomic absorption | 0.001 | ||
| Arsenic | 0.0106 | Atomic absorption; furnace | 0.001 |
| Atomic absorption; platform - stabilized temperature | 0.00057 | ||
| Atomic absorption; gaseous hydride | 0.001 | ||
| ICP-mass spectrometry | 0.00148 | ||
| Asbestos | 7 MFL1 | Transmission electron microscopy | 0.01 MFL |
| Barium | 2 | Atomic absorption; furnace | 0.002 |
| Atomic absorption; direct aspiration | 0.1 | ||
| Inductively coupled plasma | 0.002 (0.001) | ||
| Beryllium | 0.004 | Atomic absorption; furnace | 0.0002 |
| Atomic absorption; platform | 0.000025 | ||
| Inductively coupled plasma2 | 0.0003 | ||
| ICP-mass spectrometry | 0.0003 | ||
| Cadmium | 0.005 | Atomic absorption; furnace | 0.0001 |
| Inductively coupled plasma | 0.001 | ||
| Chromium | 0.1 | Atomic absorption; furnace | 0.001 |
| Inductively coupled plasma | 0.007 (0.001) | ||
| Cyanide | 0.2 | Distillation, spectrophotometric3 | 0.02 |
| Distillation, automated spectrophotometric 3 | 0.005 | ||
| Distillation, selective electrode3 | 0.05 | ||
| Distillation, amenable, spectrophotometric4 | 0.02 | ||
| Fluoride | 4.0 | Colorimetric SPADNS; with distillation | 0.1 |
| Potentiometric ion selective electrode | 0.1 | ||
| Automated alizarin fluoride blue; with distillation (complexone) | 0.05 | ||
| Automated ion selective electrode | 0.1 | ||
| Mercury | 0.002 | Manual cold vapor technique | 0.0002 |
| Automated cold vapor technique | 0.0002 | ||
| Nitrate | 10 (as N) | Manual cadmium reduction | 0.01 |
| Automated hydrazine reduction | 0.01 | ||
| Automated cadmium reduction | 0.05 | ||
| Ion selective electrode | 1 | ||
| Ion chromatography | 0.01 | ||
| Nitrite | 1 (as N) | Spectrophotometric | 0.01 |
| Automated cadmium reduction | 0.05 | ||
| Manual cadmium reduction | 0.01 | ||
| Ion chromatography | 0.004 | ||
| Selenium | 0.05 | Atomic absorption; furnace | 0.002 |
| Atomic absorption; gaseous hydride | 0.002 | ||
| Thallium | 0.002 | Atomic absorption; furnace | 0.001 |
| Atomic absorption; platform | 0.00075 | ||
| ICP-mass spectrometry | 0.0003 |
1 MFL = million
fibers per liter greater than ten (10) micrometers.
2 Using a 2 × preconcentration step as
noted in Method 200.7. Lower method detection limits may be achieved when using
a 4 ×
preconcentration.
3 Screening method for total
cyanides.
4 Measures "free"
cyanides.
5 Lower method detection
limits are reported using stabilized temperature graphite furnace atomic
absorption.
6 The value for arsenic
is effective January 1, 2006. Until then, the MCL is 0.05 mg/l.
7 The MDL reported for EPA Method 200.9
(Atomic Absorption; Platform - Stabilized Temperature) was determined using a
2× concentration step during sample digestion. The MDL determined for
samples analyzed using direct analyses, that is, no sample digestion, will be
higher. Using multiple depositions, EPA 200.9 is capable of obtaining MDL of
0.0001 mg/l.
8 Using selective ion
monitoring, EPA Method 200.8 (ICP-MS) is capable of obtaining an MDL of 0.0001
mg/l.
(B) If the
population served by the system is greater than three thousand three hundred
(3,300) persons, then compositing may only be permitted by the commissioner at
sampling points within a single system. In systems serving fewer than or equal
to three thousand three hundred (3,300) persons, the commissioner may permit
compositing among different systems provided the five (5) sample limit is
maintained.
(C) If duplicates of
the original sample taken from each sampling point used in the composite sample
are available, the system may use these instead of resampling. The duplicate
must be analyzed and the results reported to the commissioner within fourteen
(14) days after completing analysis of the composite sample, provided the
holding time of the sample is not exceeded.
(5) The frequency of monitoring for:
(A) asbestos shall be in accordance with
subsection (d);
(B) antimony,
arsenic, barium, beryllium, cadmium, chromium, cyanide, fluoride, nickel,
mercury, selenium, and thallium shall be in accordance with subsection
(e);
(C) nitrate shall be in
accordance with subsection (f); and
(D) nitrite shall be in accordance with
subsection (g).
(d) The frequency of monitoring conducted to determine compliance with the MCL for asbestos specified in section 4(d) of this rule shall be conducted as follows:
(1)
Each CWS and NTNCWS is required to monitor for asbestos during the first three
(3) year compliance period of each nine (9) year compliance cycle beginning in
the compliance period starting January 1, 1993.
(2) If the system believes it is not
vulnerable to either asbestos contamination in its source water or due to
corrosion of asbestos-cement pipe, or both, it may apply to the commissioner
for a waiver of the monitoring requirement in subdivision (1). If the
commissioner grants the waiver, the system is not required to
monitor.
(3) The commissioner may
grant a waiver based upon a consideration of the following factors:
(A) Potential asbestos contamination of the
water source.
(B) The use of
asbestos-cement pipe for finished water distribution and the corrosive nature
of the water.
(4) A
waiver remains in effect for the initial monitoring of the first three (3) year
compliance period. Systems not receiving a waiver must monitor in accordance
with subdivision (1).
(5) A system
vulnerable to asbestos contamination due solely to corrosion of asbestos-cement
pipe shall take one (1) sample at a tap served by asbestos-cement pipe and
under conditions where asbestos contamination is most likely to
occur.
(6) A system vulnerable to
asbestos contamination due solely to source water shall monitor in accordance
with subsection (c).
(7) A system
vulnerable to asbestos contamination due both to its source water supply and
corrosion of asbestos-cement pipe shall take one (1) sample at a tap served by
asbestos-cement pipe and under conditions where asbestos contamination is most
likely to occur.
(8) A system that
exceeds the MCLs as determined in section 4 of this rule shall monitor
quarterly beginning in the next quarter after the violation occurred.
(9) The commissioner may decrease the
quarterly monitoring requirement to the frequency specified in subdivision (1)
provided the commissioner has determined that the system is reliably and
consistently below the MCL. In no case can the commissioner make this
determination unless a ground water system takes a minimum of two (2) quarterly
samples and a surface (or combined surface/ground) water system takes a minimum
of four (4) quarterly samples.
(10)
If monitoring data collected after January 1, 1990, are generally consistent
with this subsection, then the commissioner may allow systems to use that data
to satisfy the monitoring requirement for the initial compliance period
beginning January 1, 1993.
(e) The frequency of monitoring conducted for nickel and to determine compliance with the MCLs in section 4 of this rule for antimony, arsenic, barium, beryllium, cadmium, chromium, cyanide, fluoride, mercury, selenium, and thallium shall be as follows:
(1) Ground water systems shall take one (1)
sample at each sampling point during each compliance period. Surface water
systems (or combined surface/ground) shall take one (1) sample annually at each
sampling point.
(2) The system may
apply to the commissioner for a waiver from the monitoring frequencies
specified in subdivision (1).
(3) A
condition of the waiver shall require that a system take a minimum of one (1)
sample while the waiver is effective. The term during which the waiver is
effective shall not exceed one (1) compliance cycle, which is nine (9)
years.
(4) The commissioner may
grant a waiver provided surface water systems have monitored annually for at
least three (3) years and ground water systems have conducted a minimum of
three (3) rounds of monitoring. (At least one (1) sample shall have been taken
since January 1, 1990.) Both surface and ground water systems shall demonstrate
that all previous analytical results were less than the MCL. Systems that use a
new water source are not eligible for a waiver until three (3) rounds of
monitoring from the new source have been completed. The commissioner may grant
a public water system a waiver for monitoring of cyanide, provided that the
commissioner determines that the system is not vulnerable due to lack of any
industrial source of cyanide.
(5)
In determining the appropriate reduced monitoring frequency, the commissioner
shall consider the following:
(A) Reported
concentrations from all previous monitoring.
(B) The degree of variation in reported
concentrations.
(C) Other factors
that may affect contaminant concentrations such as changes in:
(i) ground water pumping rates;
(ii) the system's configuration;
(iii) the system's operating procedures;
or
(iv) stream flows or
characteristics.
(6) A decision by the commissioner 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 commissioner or upon
an application by the public water system. The public water system shall
specify the basis for its request. The commissioner shall review and, where
appropriate, revise the 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 becomes available.
(7) Systems that exceed the MCLs as
calculated in subsection (k) shall monitor quarterly beginning in the next
quarter after the violation occurred.
(8) The commissioner may decrease the
quarterly monitoring requirement to the frequencies specified in subdivisions
(1) and (2) provided it has determined that the system is reliably and
consistently below the MCL. In no case can the commissioner make this
determination unless a ground water system takes a minimum of two (2) quarterly
samples and a surface water system takes a minimum of four (4) quarterly
samples.
(9) All new systems or
systems that use a new source of water that begin operation after January 1,
2004, must demonstrate compliance with the MCL within a period of time
specified by the commissioner. The system must also comply with the initial
sampling frequencies specified by the commissioner to ensure a system can
demonstrate compliance with the MCL. Routine and increased monitoring
frequencies shall be conducted in accordance with this section.
(f) All public water systems (CWSs, NTNCWSs, and TWSs) shall monitor to determine compliance with the MCL for nitrate in section 4(a) of this rule under the following monitoring schedules:
(1) CWSs and NTNCWSs served by
ground water systems shall monitor annually beginning January 1, 1993; systems
served by surface water shall monitor quarterly beginning January 1,
1993.
(2) For CWSs and NTNCWSs, the
repeat monitoring frequency for ground water systems shall be quarterly for at
least one (1) year following any one (1) sample in which the concentration is
greater than or equal to fifty percent (50%) of the MCL. The commissioner may
allow a ground water system to reduce the sampling frequency to annually after
four (4) consecutive quarterly samples are reliably and consistently less than
the MCL.
(3) For CWSs and NTNCWSs,
the commissioner may allow a surface water system to reduce the sampling
frequency to annually if all analytical results from four (4) consecutive
quarters are less than fifty percent (50%) of the MCL. A surface water system
shall return to quarterly monitoring if any one (1) sample is greater than or
equal to fifty percent (50%) of the MCL.
(4) Each TWS shall monitor annually beginning
January 1, 1993.
(5) After the
initial round of quarterly sampling is completed, each CWS and NTNCWS that is
monitoring annually shall take subsequent samples during the quarter that
previously resulted in the highest analytical result.
(g) All public water systems (CWSs, NTNCWSs, and TWSs) shall monitor to determine compliance with the MCL for nitrite in section 4(a) of this rule under the following monitoring schedules:
(1) All public water systems shall take one
(1) sample at each sampling point in the compliance period beginning January 1,
1993, and ending December 31, 1995.
(2) After the initial sample, systems where
an analytical result for nitrite is less than fifty percent (50%) of the MCL
shall monitor at the frequency specified by the commissioner.
(3) For CWSs, NTNCWSs, and TWSs, the repeat
monitoring frequency for any water system shall be quarterly for at least one
(1) year following any one (1) sample in which the concentration is greater
than or equal to fifty percent (50%) of the MCL. The commissioner may allow a
system to reduce the sampling frequency from quarterly to annually after
determining the system is reliably and consistently less than the
MCL.
(4) Systems that are
monitoring annually shall take each subsequent sample during the quarter that
previously resulted in the highest analytical result.
(h) Confirmation sampling shall be as follows:
(1) Where the results of sampling
for:
(A) antimony;
(B) arsenic;
(C) asbestos;
(D) barium;
(E) beryllium;
(F) cadmium;
(G) chromium;
(H) cyanide;
(I) fluoride;
(J) mercury;
(K) selenium; or
(L) thallium;
indicate the MCL has been exceeded, the commissioner may require that one (1) additional sample be collected as soon as possible after the initial sample was taken (but not to exceed two (2) weeks) at the same sampling point.
(2) Where nitrate or nitrite sampling results
indicate the MCL has been exceeded, the system shall take a confirmation sample
within twenty-four (24) hours of the system's receipt of notification of the
analytical results of the first sample. Systems unable to comply with the
twenty-four (24) hour sampling requirement must immediately notify the
consumers served by the public water system in accordance with
327 IAC
8-2.1-7 through
327
IAC 8-2.1-16. Systems exercising this option must take
and analyze a confirmation sample within two (2) weeks of notification of the
analytical results of the first sample.
(3) If a commissioner-required confirmation
sample is taken for any contaminant, the results of the initial and
confirmation sample shall be averaged. The resulting average shall be used to
determine the system's compliance in accordance with subsection (k). The
commissioner has the discretion to delete results of obvious sampling
errors.
(i) The commissioner may require:
(1) more frequent
monitoring than specified in subsections (d) through (g); or
(2) confirmation samples; for positive and
negative results.
(j) Systems may apply to the commissioner to conduct more frequent monitoring than the minimum monitoring frequencies specified in this section.
(k) Compliance with section 4 of this rule shall be determined based on the analytical results obtained at each sampling point in the following manner:
(1) For
systems that are conducting monitoring at a frequency greater than annual,
compliance with the MCLs for:
(A)
antimony;
(B) arsenic;
(C) asbestos;
(D) barium;
(E) beryllium;
(F) cadmium;
(G) chromium;
(H) cyanide;
(I) fluoride;
(J) mercury;
(K) selenium; or
(L) thallium;
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 (1) 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 (0) for the purpose of determining the annual average. If a system fails to collect the required number of samples, compliance (average concentration) will be based on the total number of samples collected.
(2) For systems that are monitoring annually,
or less frequently, the system is out of compliance with the MCLs for:
(A) antimony;
(B) arsenic;
(C) asbestos;
(D) barium;
(E) beryllium;
(F) cadmium;
(G) chromium;
(H) cyanide;
(I) fluoride;
(J) mercury;
(K) selenium; or
(L) thallium;
if the level of a contaminant at any sampling point is greater than the MCL. If a confirmation sample is required by the commissioner, the determination of compliance will be based on the annual average of the initial MCL exceedance and any commissioner-required confirmation samples. If a system fails to collect the required number of samples, compliance (average concentration) will be based on the total number of samples collected.
(3) Compliance with the
MCLs for nitrate and nitrite is determined based on one (1) sample if the
levels of these contaminants are below the MCLs. If the levels of nitrate or
nitrite, or both, exceed the MCLs in the initial sample, a confirmation sample
is required in accordance with subsection (h)(2), and compliance shall be
determined based upon the average of the initial and confirmation
samples.
(4) If a public water
system has a distribution system separable from other parts of the distribution
system with no interconnections, the commissioner may allow the system to give
public notice to only the area served by that portion of the system that is out
of compliance.
(5) Beginning
January 1, 2006, arsenic sampling results will be reported to the nearest
one-thousandth (0.001) mg/l.
(l) Each public water system shall monitor at the time designated by the commissioner during each compliance period. (m) Sample collection for:
(1)
antimony;
(2) arsenic;
(3) asbestos;
(4) barium;
(5) beryllium;
(6) cadmium;
(7) chromium;
(8) cyanide;
(9) fluoride;
(10) mercury;
(11) nickel;
(12) nitrate;
(13) nitrite;
(14) selenium; and
(15) thallium;
under this section shall be conducted using the sample preservation, container, and maximum holding time procedures specified in the following table:
| Contaminant | Preservative3 | Container1 | Time2 |
| Antimony | HNO3 | P or G | 6 months |
| Arsenic | HNO3 | P or G | 6 months |
| Asbestos | 4°C | P or G | 48 hours4 |
| Barium | HNO3 | P or G | 6 months |
| Beryllium | HNO3 | P or G | 6 months |
| Cadmium | HNO3 | P or G | 6 months |
| Chromium | HNO3 | P or G | 6 months |
| Cyanide | 4°C, NaOH | P or G | 14 days |
| Fluoride | none | P or G | 1 month |
| Mercury | HNO3 | P or G | 28 days |
| Nickel | HNO3 | P or G | 6 months |
| Nitrate | 4°C | P or G | 48 hours5 |
| Nitrate-nitrite6 | H2SO4 | P or G | 28 days |
| Nitrite | 4°C | P or G | 48 hours |
| Selenium | HNO3 | P or G | 6 months |
| Thallium | HNO3 | P or G | 6 months |
1 P = Plastic,
hard or soft; G = glass.
2 In all
cases, samples should be analyzed as soon after collection as possible. Follow
additional (if any) information on preservation, containers, or holding times
that is specified in method.
3 When
indicated, samples must be acidified at the time of collection to pH < 2
with concentrated acid or adjusted with sodium hydroxide to pH > 12. When
chilling is indicated the sample must be shipped and stored at four (4) degrees
Celsius or less.
4 Instructions for
containers, preservation procedures, and holding times as specified in Method
100.2 must be adhered to for all compliance analyses including those conducted
with Method 100.1.
5 If the sample
is chlorinated, the holding time for an unacidified sample kept at four (4)
degrees Celsius is extended to fourteen (14)
days.
6
Nitrate-nitrite refers to a measurement of total nitrate.
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