Ohio Administrative Code
Title 3745 - Ohio Environmental Protection Agency
Chapter 3745-81 - Primary Drinking Water Rules
Section 3745-81-24 - Organic chemical monitoring requirements
Universal Citation: OH Admin Code 3745-81-24
Current through all regulations passed and filed through March 18, 2024
Monitoring requirements for organic chemical contaminants of drinking water are stated in this rule. Analytical procedures which are acceptable for monitoring for organic contaminants in drinking water are listed in rule 3745-81-27 of the Administrative Code. Analyses under this rule shall only be conducted by laboratories that are certified for these analyses under Chapter 3745-89 of the Administrative Code. Community public water systems and nontransient noncommunity public water systems shall monitor for organic chemicals according to a schedule provided by the director.
(A) Monitoring for volatile organic chemicals with maximum contaminant levels (MCLs) listed in paragraph (C) of rule 3745-81-12 of the Administrative Code shall be conducted by community public water systems and nontransient noncommunity public water systems as follows:
(1) Groundwater systems shall monitor with a
minimum of one sample at each respective sampling point during each compliance
period. Surface water systems shall monitor with a minimum of one sample
annually at each sampling point. After the first set of samples, each repeat
sample shall be taken at the same sampling point as used before unless
conditions make another sampling point more representative of a source,
treatment plant, or part of the distribution system.
(2) If a public water system draws water from
more than one source and the sources are combined before distribution, the
public water system shall monitor at each sampling point during periods of
normal operating conditions and shall keep a record of and report the sources
providing water for each sample. When a sample does not contain water from all
the sources which serve the sampling point, the public water system shall
prepare and follow a schedule such that the next monitoring sample at this
sampling point for the same volatile organic chemicals will include water from
sources not included in the previous sample or samples. Thus, successive
samples from the same sampling point for the same volatile organic chemicals
shall sample water supplied from different sources until all the sources
supplying that sampling point have been monitored.
(3) Each
new community and new nontransient noncommunity public water system and public
water systems that use a new source of water shall monitor initially with four
consecutive quarterly samples for each contaminant listed in paragraph
(C) of
rule
3745-81-12
of the Administrative Code beginning in the first quarter of the next calendar
year after operation of the new source of system begins. New public water
systems shall sample at each sampling point; systems with a new source of water
shall sample at the sampling point related to the new source.
(4) If the initial monitoring for the
contaminants listed in paragraph (C) of rule
3745-81-12
of the Administrative Code has been completed and the public water system did
not detect any contaminant listed in paragraph (C) of rule
3745-81-12
of the Administrative Code, then the public water system shall monitor with one
sample annually. For any contaminant detected during the initial monitoring,
the public water system shall continue quarterly monitoring until eligible for
a reduction under paragraph (A)(6)(b) of this rule.
(5) The director may, after a minimum of
three years of annual monitoring with no detection of any contaminant listed in
paragraph (C) of rule
3745-81-12
of the Administrative Code, reduce monitoring by a groundwater system to one
sample during each compliance period.
(6) If a contaminant listed in paragraph
(C) of
rule
3745-81-12
of the Administrative Code is detected at a level exceeding 0.0005 milligram
per liter in any sample, then:
(a) The public
water system shall monitor quarterly at each sampling point which resulted in a
detection. If a public water system is monitoring annually or less frequently
for a previously detected contaminant, then the public water system does not
have to return to quarterly monitoring for that contaminant unless the sample
result exceeds eighty per cent of the MCL.
(b) The director may decrease the quarterly
monitoring requirement specified in paragraph (A)(6)(a) of this rule to annual
monitoring provided the director has determined that the public water system
does not exceed eighty per cent of the MCL for that contaminant. In no case
shall the director make this determination unless a groundwater system has
monitored with a minimum of two consecutive quarterly samples and a surface
water system has monitored with a minimum of four consecutive quarterly
samples.
(c) Public water systems
which monitor annually for a previously detected contaminant shall monitor
during the quarters which previously yielded the highest
analytical result.
(7)
The director may require a confirmation sample for positive or negative
results. If a confirmation sample is required by the director, the result shall
be averaged with the first sampling result and the average used for the
compliance determination as specified by paragraph (A)(8) of this
rule.
(8) Compliance with paragraph
(C) of
rule
3745-81-12
of the Administrative Code shall be determined based on the analytical results
obtained at each sampling point.
(a) For
public water systems which are conducting monitoring at a frequency greater
than annually, compliance is determined by a running annual average of all
samples taken at each sampling point. If the running annual average of any
sampling point is greater than the MCL, then the public water system is out of
compliance. The system will not be considered in violation of the MCL until it
has completed one year of quarterly sampling. If, however, the initial sample
or a subsequent sample would cause the running annual average to exceed the
MCL, then the public water system is out of compliance immediately. Any samples
below the detection limit shall be counted as zero for purposes of determining
the running annual average.
(b) For
public water systems monitoring annually or less frequently, when the average
of a result and a required confirmation sample exceeds eighty per cent of the
MCL, the public water system shall begin quarterly monitoring at that sample
point. If a confirmation sample was not collected, the public water system
shall begin quarterly monitoring if the level of the initial sample exceeds
eighty per cent of the MCL. Compliance with a MCL will be determined by a
running annual average as stated in paragraph (A)(8)(a) of this rule. If one
sampling point is in violation of the MCL, the system is in violation of the
MCL.
(c) If a public water system
fails to collect the required number of samples, compliance will be based on
the total number of samples collected.
(9) Analysis for the contaminants listed in
paragraph (C) of rule
3745-81-12
of the Administrative Code shall be conducted using the methods in rule
3745-81-27
of the Administrative Code.
(10) Analysis under this rule shall only be
conducted by laboratories that are approved under Chapter 3745-89 of the
Administrative Code.
(11) The
director has discretion to delete results of obvious sampling or analytical
errors.
(12) The director may
increase required monitoring where necessary to detect variations within the
public water system.
(13) Each
approved laboratory shall determine the method detection limit (MDL), as
defined in the appendix to rule
3745-89-03
of the Administrative Code, at which it is capable of detecting volatile
organic chemicals. The acceptable MDL is 0.0005 milligram per liter. This
concentration is the detection concentration for purposes of this
rule.
(B) Monitoring of the organic chemical contaminants with maximum contaminant levels listed in paragraph (D) of rule 3745-81-12 of the Administrative Code shall be conducted by community public water systems and nontransient noncommunity public water systems as follows:
(1)
Groundwater systems and surface water systems shall monitor with a minimum of
one sample at each sampling point each time monitoring is required in paragraph
(B) of this rule. After the initial set of samples, each sample shall be taken
at the same sampling point as used before unless conditions make another
sampling point more representative of a source or treatment plant.
(2) If the public water system draws water
from more than one source and the sources are combined before distribution, the
public water system shall monitor at each sampling point during periods of
normal operating conditions and shall keep a record of and report the sources
providing water for each sample. When a sample does not contain water from all
the sources which serve the sampling point, a schedule prepared by the public
water system shall be followed so that the next monitoring sample at this
sampling point for the same organic chemicals
will include water from sources not included in the previous sample or samples.
Thus, successive samples from the same sampling point for the same organic
chemicals shall sample water supplied from different
sources until all the sources supplying that sampling point have been
monitored.
(3) Monitoring
frequency:
(a) Each community public water
system and nontransient noncommunity public water system shall monitor with
four consecutive quarterly samples at each sampling point for each organic
chemical contaminant listed in paragraph (D) of rule
3745-81-12
of the Administrative Code during each compliance period.
(b) Public water systems serving more than
three thousand three hundred persons which do not detect a contaminant listed
in paragraph (D)
of rule
3745-81-12
of the Administrative Code in their first compliance period may reduce the
sampling frequency to a minimum of two quarterly samples in one year during
each following compliance period.
(c) Public water systems serving fewer than
three thousand three hundred one persons which do not detect a contaminant
listed in paragraph (D) of rule
3745-81-12
of the Administrative Code in their first compliance period may reduce the
sampling frequency to a minimum of one sample during each following compliance
period.
(d) Public water systems
that use a new source of water and new public water systems shall begin initial
quarterly monitoring for each contaminant listed in paragraph
(D) of
rule
3745-81-12
of the Administrative Code in a quarter designated by the director during the
next calendar year after operation of the new source or system begins. New
public water systems shall sample at each sampling point. Public water systems
with a new source of water shall sample at the sampling point related to the
new source.
(4) The
director may grant a waiver from one or more requirements of paragraphs
(B)(3)(a) to (B)(3)(c) of this rule. Each waiver is valid for only one
compliance period.
(5) The director
may grant a waiver after evaluating the previous use (including transport,
storage, or disposal) of a contaminant listed in paragraph
(D) of
rule
3745-81-12
of the Administrative Code within the watershed or zone of influence of the
public water system. If a determination by the director reveals no previous use
of the contaminant within the watershed or zone of influence, a waiver may be
granted. If the contaminant has been used previously or if
the
previous use is unknown, then the following factors shall be used to
determine whether a waiver is granted:
(a) Previous
analytical results.
(b) The
proximity of the public water system to a potential point or nonpoint source of
contamination. Point sources include spills and leaks of chemicals at or near a
water treatment facility or at manufacturing, distribution, or storage
facilities or from hazardous and municipal waste landfills and other waste
handling or treatment facilities. Nonpoint sources include the use of
pesticides to control insect and weed pests on agricultural areas, forest
lands, homes and gardens, and other land application uses.
(c) The environmental persistence and
transport of the organic chemicals listed in paragraph
(D) of
rule
3745-81-12
of the Administrative Code.
(d) How
completely the water source is protected against contamination due to such
factors as the depth of the well, the type of soil, and the integrity of the
well casing.
(e) Elevated nitrate
levels at the public water system source.
(f) Use of polychlorinated biphenyls in
equipment used in the production, storage, or distribution of water (e.g.,
polychlorinated biphenyls used in pumps, transformers, etc.).
(6) If an organic chemical
contaminant listed in paragraph (D) of rule
3745-81-12
of the Administrative Code is detected (as defined by paragraph (B)(14) of this
rule) in any sample, then:
(a) Each public
water system shall monitor quarterly at each sampling point which resulted in a
detection. If a public water system is monitoring annually or less frequently
for a previously detected contaminant, then the public water system does not
have to return to quarterly monitoring unless the sample result exceeds eighty
per cent of the MCL.
(b) The
director may decrease the quarterly monitoring requirement specified in
paragraph (B)(6)(a) of this rule to annual monitoring provided the director has
determined that the public water system does not exceed eighty per cent of the
MCL. In no case shall 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.
(c) Public water systems which monitor
annually shall monitor during the quarter that previously yielded the highest
analytical result.
(d) For public
water systems which have three consecutive annual samples with no detection of
a contaminant listed in paragraph (D) of rule
3745-81-12
of the Administrative Code, the director may grant a waiver as specified in
paragraph (B)(4) of this rule.
(e)
If monitoring results in detection of one or more of certain related
contaminants (heptachlor, heptachlor epoxide), then subsequent monitoring shall
analyze for all related contaminants.
(7) The director may require a confirmation
sample for positive or negative results. If a confirmation sample is required
by the director, the result shall be averaged with the first monitoring result
and the average used for the compliance determination as specified by paragraph
(B)(8) of this rule.
(8) Compliance
with paragraph (D) of rule
3745-81-12
of the Administrative Code shall be determined based on the analytical results
obtained at each sampling point, as follows:
(a)
For public water systems which are conducting monitoring at a frequency greater
than annual, compliance is determined by a running annual average of all
samples taken at each sampling point. The system will not be considered in
violation of the MCL until it has completed one year of quarterly monitoring.
If, however, the initial result or a subsequent result would cause the running
annual average to exceed the MCL, then the public water system is out of
compliance immediately. If a system fails to collect the required number of
samples, compliance will be based on the total number of samples collected. If
one sampling point is in violation of the MCL, the system is in violation of
the MCL. Any results below the detection limit shall be calculated as zero for
purposes of determining the running annual average.
(b) For public water systems monitoring
annually or less frequently, when the average of a result and a confirmation
sample exceeds eighty per cent of the MCL the public water system shall begin
quarterly monitoring at that sample point. If a confirmation sample was not
collected, the public water system shall begin quarterly monitoring if the
level of the initial sample exceeds eighty percent of the MCL. Compliance with
the MCL will then be determined by a running annual average as stated in
paragraph (B)(8) (a) of this rule.
(9) Analysis for the organic chemical
contaminants listed in paragraph (D) of rule
3745-81-12
of the Administrative Code shall be conducted by using methods set forth in
rule
3745-81-27
of the Administrative Code.
(10)
Analysis for polychlorinated biphenyls shall be conducted as follows:
(a) Each public water system which monitors
for polychlorinated biphenyls shall analyze or have analyzed each sample using
a technique set forth in rule
3745-81-27
of the Administrative Code.
(b) If
polychlorinated biphenyls (as one of seven aroclors) are detected (as
designated in this paragraph) in any sample analyzed using a technique set
forth in rule
3745-81-27
of the Administrative Code, the sample shall be reanalyzed using a technique
set forth in rule
3745-81-27
of the Administrative Code to quantitate polychlorinated biphenyls (as
decachlorobiphenyl).
(c) Compliance
with the MCL for polychlorinated biphenyls shall be determined based upon the
quantitative results of analyses using a technique set forth in rule
3745-81-27
of the Administrative Code.
|
Aroclor |
Detection limit (Milligrams per liter) |
|
1016 |
0.00008 |
|
1221 |
0.02 |
|
1232 |
0.0005 |
|
1242 |
0.0003 |
|
1248 |
0.0001 |
|
1254 |
0.0001 |
|
1260 |
0.0002 |
(11) The director has discretion to delete
results of obvious sampling or analytical errors.
(12) The director may increase the required
monitoring frequency, where necessary, to detect variations within the public
water system (e.g., fluctuations in concentration due to seasonal use, changes
in water source).
(13) Each public
water system shall monitor at the time designated by the director within each
compliance period.
(14) Detection
as used in this rule shall be defined as greater than or equal to the following
concentration for each contaminant.
|
Contaminant |
Detection limit (Milligrams per liter) |
|
Alachlor |
0.0002 |
|
Atrazine |
0.0001 |
|
Benzo(A)pyrene |
0.00002 |
|
Carbofuran |
0.0009 |
|
Chlordane |
0.0002 |
|
Dalapon |
0.001 |
|
1,2-Dibromo-3-chloropropane (DBCP) |
0.00002 |
|
Di(2-ethylhexyl) adipate |
0.0006 |
|
Di(2-ethylhexyl) phthalate |
0.0006 |
|
Dinoseb |
0.0002 |
|
Diquat |
0.0004 |
|
2,4-d |
0.0001 |
|
Endothall |
0.009 |
|
Endrin |
0.00001 |
|
Ethylene dibromide (EDB) |
0.00001 |
|
Glyphosate |
0.006 |
|
Heptachlor |
0.00004 |
|
Heptachlor epoxide |
0.00002 |
|
Hexachlorobenzene |
0.0001 |
|
Hexachlorocyclopentadiene |
0.0001 |
|
Lindane |
0.00002 |
|
Methoxychlor |
0.0001 |
|
Oxamyl |
0.002 |
|
Pentachlorophenol |
0.00004 |
|
Picloram |
0.0001 |
|
Pentachlorophenol |
0.00004 |
|
Polychlorinated biphenyls (PCBs) (As decachlorobiphenyl) |
0.0001 |
|
Simazine |
0.00007 |
|
Toxaphene |
0.001 |
|
2,3,7,8-TCDD (dioxin) |
0.000000005 |
|
2,4,5-TP (silvex) |
0.0002 |
(C) Monitoring for total trihalomethanes (TTHM) and haloacetic acids five (HAA5).
(1)
Community public water systems and nontransient noncommunity public water
systems that treat their water with any combination of primary or residual
disinfectant, other than ultraviolet light, or delivers water that has been
treated with any combination of primary or residual disinfectant, other than
ultraviolet light, shall monitor for TTHM and HAA5 according to paragraph (C)
of this rule. The director will determine compliance with MCLs for TTHMs and
HAA5.
(2) For public water systems
required to conduct quarterly monitoring, compliance with MCLs for TTHMs and
HAA5 shall be based on a locational running annual arithmetic average at each
monitoring location, calculated quarterly, at the end of the fourth calendar
quarter following the compliance date and at the end of each subsequent quarter
(or earlier if the LRAA calculated based on fewer than four quarters of data
would cause the MCL to be exceeded regardless of the monitoring results of
subsequent quarters). For public water systems monitoring quarterly, if the
system fails to complete four consecutive quarters of monitoring, compliance
with the MCL for the last four quarter compliance period
shall be
based on the average of the available data from the most recent four
quarters.
(3) If the public water
system is required to conduct monitoring at a frequency that is less than
quarterly, compliance with MCLs shall be based on the LRAA calculations
beginning with the first compliance sample taken after the compliance date. If
any sample result exceeds the MCL, the public water system
shall
comply with the requirements of paragraphs (C)(18) to (C)(20) of this rule. If
no sample exceeds the MCL, the sample result for each monitoring location is
considered the LRAA for that monitoring location.
(4) If a public water system takes more than
one sample per quarter at a monitoring location, the average of all samples
taken in the quarter at that location shall be used to
determine a quarterly average to be used in the LRAA calculation.
(5) If the public water system fails to
monitor according to the sample monitoring plan, the system will be in
violation for the entire period covered by the locational running annual
average. Public water systems shall take all samples during normal operating
conditions.
(6) Routine monitoring
for TTHMs and HAA5: Public water systems are required to begin monitoring at
the locations and the time period identified in the sample monitoring plan
developed under paragraph (C)(9) of this rule. Public water systems specified
in paragraph (C)(1) of this rule shall monitor at the frequency indicated and
at no fewer than the number of locations identified in the following table:
|
Source water type |
Population size category |
Monitoring frequency1 |
Sample Type2 |
Distribution system monitoring location total per monitoring period2 |
|
Surface water |
<500 |
Per year |
Individual samples |
2 |
|
500-3,300 |
Every 90 days |
Individual samples |
2 |
|
|
Surface water |
3,301-9,999 |
Every 90 days |
Dual sample set |
2 |
|
10,000-49,999 |
Every 90 days |
Dual sample set |
4 |
|
|
Surface water |
50,000- 249,999 |
Every 90 days |
Dual sample set |
8 |
|
250,000-999,999 |
Every 90 days |
Dual sample set |
12 |
|
|
Surface water |
1,000,000-4,999,999 |
Every 90 days |
Dual sample set |
16 |
|
> or = 5,000,000 |
Every 90 days |
Dual sample set |
20 |
|
|
Ground water |
<500 |
Per year |
Individual samples |
2 |
|
500-9,999 |
Per year |
Dual sample set |
2 |
|
|
Ground water |
10,000-99,999 |
Every 90 days |
Dual sample set |
4 |
|
100,000-499,999 |
Every 90 days |
Dual sample set |
6 |
|
|
Ground water |
> or = 5,000,000 |
Every 90 days |
Dual sample set |
8 |
|
1 All systems shall monitor during month of highest DBP concentrations. |
||||
|
2 Systems on quarterly monitoring shall take dual sample sets every 90 days at each monitoring location except for surface water systems serving 500-3,300. Ground water systems serving 500-9,999 on annual monitoring shall take dual sample sets at each monitoring location. All other systems on annual monitoring and surface water systems serving 500-3,300 are required to take individual TTHM and HAA5 samples (instead of a dual sample set) at the locations with the highest TTHM and HAA5 concentrations, respectively. For systems serving fewer than 500 people, only one location with a dual sample set per monitoring period is needed if the highest TTHM and HAA5 concentrations occur at the same location and month. |
||||
(7)
Systems on quarterly monitoring are required to monitor every ninety days. The
ninety day monitoring frequency may be extended or reduced by five days to
allow for unplanned circumstances that prevent monitoring precisely ninety days
apart, as long as the samples are collected during each calendar
quarter.
(8) If a system that does
not disinfect begins using a disinfectant other than UV light, the system
shall
consult with the director to identify compliance monitoring locations and
develop a monitoring plan under paragraph (C)(9) of this rule that includes
those monitoring locations.
(9)
Each public water system required to monitor for TTHM and HAA5 shall develop
and implement a sample monitoring plan. The public water system shall maintain
the plan and make it available for inspection by the director and the general
public. The monitoring plan shall contain the following elements: monitoring
locations (including both a location address and sample monitoring point code);
monitoring dates; and alternate monitoring locations (in the event access to a
primary location is not available). The director will determine compliance with
MCLs for TTHMs and HAA5.
(10)
Monitoring locations shall be chosen by alternating selection of locations
representing high TTHM levels and high HAA5 levels until the required number of
compliance monitoring locations have been identified. Public water systems
shall
also provide the rationale for identifying the locations as having high levels
of TTHM or HAA5. If a public water system has more monitoring locations than
required for compliance monitoring according to paragraph (C) of this rule,
systems shall identify which locations will be used for
compliance monitoring by alternating selection of locations representing high
TTHM levels and high HAA5 levels until the required number of compliance
monitoring locations have been identified.
(11) All surface water systems
shall
submit a copy of the monitoring plan to the director. The director may require
new community and non-transient noncommunity water systems that treat their
water with any combination of primary or residual disinfectant, other than
ultraviolet light, or deliver water that has been treated with any combination
of primary or residual disinfectant, other than ultraviolet light to develop
and submit a sample monitoring plan within twelve months of becoming
active.
(12) A public water system
may revise the monitoring plan to reflect changes in treatment, distribution
system operations and layout (including new service areas), or other factors
that may affect TTHM or HAA5 formation, or for director approved reasons, after
consultation with the director regarding the need for changes and the
appropriateness of changes. If a system changes monitoring locations, the
locations shall replace existing compliance monitoring locations
with the lowest LRAA with new locations that reflect the current distribution
system locations with expected high TTHM or HAA5 levels. The director may also
require modifications in the monitoring plan. Surface water systems
shall
submit a copy of the modified monitoring plan to the director prior to the date
required to comply with the revised monitoring plan.
(13) Reduced monitoring for TTHMs and HAA5:
Public water systems may reduce monitoring to the level specified in the
following table any time the LRAA is less than or equal to 0.040 mg/L for TTHM
and less than or equal to 0.030 mg/ L for HAA5 at all monitoring locations.
Systems may only use data collected under the provisions of paragraph (C) of
this rule to qualify for reduced monitoring. In addition, the source water
annual average TOC level, before any treatment, shall be less
than or equal to 4.0 mg/L at each treatment plant treating surface water, based
on monitoring conducted under rule
3745-81-77
of the Administrative Code.
|
Source water type |
Population size category |
Monitoring frequency1 |
Distribution system monitoring location total per monitoring period |
|
Surface Water: |
<500 |
NA |
Monitoring may not be reduced |
|
500-3,300 |
Per year |
1 TTHM and 1 HAA5 sample: one at the location and during the quarter with the highest TTHM single measurement, one at the location and during the quarter with the highest HAA5 single measurement; 1 dual sample set per year if the highest TTHM and HAA5 measurements occurred at the same location and quarter. |
|
|
Surface Water: |
3,301-9,999 |
Per year |
2 dual sample sets: one at the location and during the quarter with the highest TTHM single measurement, one at the location and during the quarter with the highest HAA5 single measurement. |
|
10,000-49,999 |
Every 90 days |
2 dual sample sets at the locations with the highest TTHM and highest HAA5 LRAAs. |
|
|
Surface Water: |
50,000-249,999 |
Every 90 days |
4 dual sample sets-at the locations with the two highest TTHM and two highest HAA5 LRAAs. |
|
250,000-999,999 |
Every 90 days |
6 dual sample sets-at the locations with the three highest TTHM and three highest HAA5 LRAAs. |
|
|
Surface Water: |
1,000,000-4,999,999 |
Every 90 days |
8 dual sample sets-at the locations with the four highest TTHM and four highest HAA5 LRAAs. |
|
> or = 5,000,000 |
Every 90 days |
10 dual sample sets-at the locations with the five highest TTHM and five highest HAA5 LRAAs. |
|
|
Ground Water |
<500 |
Every third year |
1 TTHM and 1 HAA5 sample: one at the location and during the quarter with the highest TTHM single measurement, one at the location and during the quarter with the highest HAA5 single measurement; 1 dual sample set per year if the highest TTHM and HAA5 measurements occurred at the same location and quarter. |
|
500-9,999 |
Per year |
1 TTHM and 1 HAA5 sample: one at the location and during the quarter with the highest TTHM single measurement, one at the location and during the quarter with the highest HAA5 single measurement; 1 dual sample set per year if the highest TTHM and HAA5 measurements occurred at the same location and quarter. |
|
|
Ground Water |
10,000-99,999 |
Per year |
2 dual sample sets: one at the location and during the quarter with the highest TTHM single measurement, one at the location and during the quarter with the highest HAA5 single measurement. |
|
100,000-499,999 |
Every 90 days |
2 dual sample sets; at the locations with the highest TTHM and highest HAA5 LRAAs. |
|
|
Ground Water |
> or = 5,000,000 |
Every 90 days |
4 dual sample sets at the locations with the two highest TTHM and two highest HAA5 LRAAs. |
|
1 Systems on quarterly monitoring shall take dual sample sets every 90 days. |
|||
(14)
Public water systems may remain on reduced monitoring as long as the TTHM LRAA
is less than or equal to 0.040 mg/L and the HAA5 LRAA is less than or equal to
0.030 mg/L at each monitoring location (for systems with quarterly reduced
monitoring) or each TTHM sample is less than or equal to 0.060 mg/L and each
HAA5 sample is less than or equal to 0.045 mg/L (for systems with annual or
less frequent monitoring). In addition, the source water annual average TOC
level, before any treatment, shall be less than or equal to 4.0 mg/L at each
treatment plant treating surface water, based on monitoring conducted under
rule
3745-81-77
of the Administrative Code.
(15) If
the LRAA based on quarterly monitoring at any monitoring location exceeds
either 0.040 mg/L for TTHM or 0.030 mg/L for HAA5 or if the annual (or less
frequent) sample at any location exceeds either 0.060 mg/L for TTHM or 0.045
mg/L for HAA5, or if the source water annual average TOC level, before any
treatment, greater than 4.0 mg/L at any treatment plant treating surface water,
the system shall resume routine monitoring under paragraph (C)(6)
of this rule or begin increased monitoring if paragraph (C)(18) of this rule
applies.
(16) The director may
return a public water system to routine monitoring at the director's
discretion, for reasons including but not limited to: treatment change,
significant distribution changes, or disinfectant changes.
(17) Consecutive systems that do not add a
disinfectant but deliver water that has been treated with a primary or residual
disinfectant other than ultraviolet light, shall comply with
analytical, monitoring, and compliance requirements for chlorine and
chloramines in rules
3745-81-27
and
3745-81-70
of the Administrative Code and report monitoring results under paragraph (G)(4)
of rule
3745-81-75
of the Administrative Code.
(18) If
a public water system is required to monitor at a particular location annually
or less frequently than annually under paragraph (C)(6) or (C)(13) of this
rule, the system shall increase monitoring to dual sample sets once per
quarter (taken every ninety days) at all locations if a TTHM sample is greater
than 0.080 mg/L or a HAA5 sample is greater than 0.060 mg/L at any
location.
(19) A public water
system is in violation of the MCL when the LRAA exceeds the MCLs in rule
3745-81-12
of the Administrative Code, calculated based on four consecutive quarters of
monitoring (or the LRAA calculated based on fewer than four quarters of data if
the system fails to complete four consecutive quarters of monitoring, or if the
MCL would be exceeded regardless of the monitoring results of subsequent
quarters). The system is in violation of the monitoring requirements for each
quarter that a monitoring result would be used in calculating an LRAA if the
system fails to monitor.
(20)
Public water systems may return to routine monitoring once increased monitoring
has been conducted for at least four consecutive quarters and the LRAA for
every monitoring location is less than or equal to 0.060 mg/L for TTHM and less
than or equal to 0.045 mg/L for HAA5.
(21) Operational evaluation levels: A public
water system has exceeded the operational evaluation level at any monitoring
location where the sum of the two previous quarters' TTHM results plus twice
the current quarter's TTHM result, divided by four to determine an average,
exceeds 0.080 mg/L, or where the sum of the two previous quarters' HAA5 results
plus twice the current quarter's HAA5 result, divided by four to determine an
average, exceeds 0.060 mg/L.
(a) If a public
water system exceeds the operational evaluation level, the system
shall
conduct an operational evaluation and submit a written report of the evaluation
to the director no later than ninety days after being notified by the director
of the analytical result that causes the system to exceed the operational
evaluation level. The written report shall be made
available to the public upon request.
(b) The public water
system's operational evaluation
shall
include an examination of system treatment and distribution operational
practices, including storage tank operations, excess storage capacity,
distribution system flushing, changes in sources or source water quality, and
treatment changes or problems that may contribute to TTHM and HAA5 formation
and what actions the PWS will take and when these actions will be
implemented to minimize future exceedances. If
the system exceeding the OEL is a consecutive water system, a master meter
monitoring location shall be submitted to the director for approval at each
master meter, or as close as possible, supplying water to each monitoring
location that exceeds the OEL.
(c) A public water system may request and the
director may allow the system to limit the scope of the evaluation if the
system is able to identify the cause of the operational evaluation level
exceedance.
(d) A request from the
system to limit the scope of the evaluation does not extend the schedule in
paragraph (C)(21)(a) of this rule for submitting the written report. The
director shall approve this limited scope of evaluation in
writing and the system shall keep that
approval with the completed report.
(22)
If a consecutive
water system exceeds the operational evaluation level or the TTHM LRAA or HAA5
LRAA is in exceedance of the MCL for two quarters within a twelve month period
and the current individual compliance monitoring period's results are greater
than the TTHM or HAA5 MCL, the following apply:
(a)
Beginning the
quarter following the second OEL or MCL exceedance, the consecutive water
system shall monitor quarterly for disinfection byproducts at the mater meter
monitoring locations acceptable to the director. The master meter monitoring
shall be conducted with routine TTHM and HAA5 compliance monitoring. The mater
meter monitoring shall be conducted for a miniumum of four consecutive quaters
unless otherwise specified by the director.
(b)
If any master
meter monitoring results collected by the consecutive water system pursuant to
paragraph (C)(22)(a) of this rule are greater than the TTHM or HAA5 MCL,
beginning the next calendar quarter the wholesale system delivering water to
the consecutive water system shall begin quarterly monitoring at or near the
respective master meter monitoring locations for a minimum of four consecutive
quarters unless otherwise specified by the director. The wholesaler's master
meter monitoring locations shall be submitted to the director for approval. The
wholesaler shall conduct monitoring at the master meter monitoring locations
concurrently with the consecutive water system in accordance with a schedule
determined by the director. If a master meter location is the same location for
both the consecutive and wholesale system, and the wholesale system and
consecutive system agree to sample from this master meter location to comply
with this rule, both systems may jointly request that the Director approve the
agreed upon master meter location.
(c)
If the
consecutive waster system or wholesale system has a sample result at any master
meter monitoring location greater than the TTHM or HAA5 MCL, after the first
quarter of wholesaler monitoring, an OEL resport shall be completed by the
consecutive water system and the wholesale system.The OEL reports shall be
completed and submitted to the director in accordance with paragraph (C)(21) of
this rule on a form accpetable to the director. An OEL report shall be
completed and submitted for each quarter when the individual quarterly sample
result at the master meter monitoring locations is greater than the TTHM or
HAA5 MCL.
(d)
Master meter monitoring locations determined to have an
LRAA that exceeds either the TTHM or HAA5 MCL shall become additional
compliance monitoing locations for the wholesale system and be subject to
paragraph (C) of this rule unless otherwise specified by the director.Upon
directors approval,the wholesale system may replace a current monitoring
location with a master meter location if the current monitoring location has
not exceeded the OEL or had an LRAA exceed an MCL for a time period determined
by the director as appropriate.
(e)
Public water
systems required to monitor at master meter locations under this rule may
reduce or stop monitoring upon directors approval at these locations if the
issue causing the elevated concentrations of DBPs has been resolved and
monitoring results at these locations are consistently below the
MCL.
(f)
The director may require additional public water
systems involved with the conveyance of water to a consecutive public water
system to comply with the requirements of this rule.
Disclaimer: These regulations may not be the most recent version. Ohio may have more current or accurate information. We make no warranties or guarantees about the accuracy, completeness, or adequacy of the information contained on this site or the information linked to on the state site. Please check official sources.
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