Nebraska Administrative Code › Topic - HEALTH AND HUMAN SERVICES SYSTEM › Title 179 - PUBLIC WATER SYSTEMS › Chapter 23 - INITIAL DISTRIBUTION SYSTEM EVALUATION (IDSE) › Section 179-23-008 - 179 NAC 24 COMPLIANCE MONITORING LOCATION RECOMMENDATIONS

Current through June 17, 2024
008.01 A system's
				IDSE report must include its recommendations and justification for where and
				during what month(s) TTHM and HAA5 monitoring for 179 NAC 24 should be
				conducted. A system must base its recommendations on the criteria in 179 NAC
				23-008.02 through 23-008.05.
008.02
				A system must select the number of monitoring locations specified in the
				following table. A system must use these recommended locations and/or the sites
				listed in 179 NAC
				24-004 as 179 NAC 24 routine
				compliance monitoring locations, unless the Department requires different or
				additional locations. A system should distribute locations throughout the
				distribution system to the extent possible.
Source water type
Population size category
Monitoring
							 frequency1
Distribution system monitoring
							 location
Total per monitoring
period2
Highest
TTHM
locations
Highest
HAA5
locations
Existing 179 NAC 16 compliance
							 locations
Surface water and GWUDI
<500
per year
2 (1 TTHM,
1
1
--
500-3,300
per quarter
1 HAA5)
1
1
3, 301-9,999
per quarter
2 (1 TTHM,
1
1
--
10, 000-49,999
per quarter
1 HAA5)
2
1
1
50, 000-249,999
per quarter
2 Dual
3
3
2
250, 000-999,999
per quarter
4 Dual
5
4
3
1,000, 000-4,999,999
per quarter
8 Dual 12
6
6
4
>=5,000,000
per quarter
16 Dual 20 Dual
8
7
5
Ground water
<500
per year
2 (1 TTHM,
1
1
--
500-9,999
per year
1 HAA5)
1
1
--
10, 000-99,999
per quarter
2 Dual
2
1
1
100, 000-499,999
per quarter
4 Dual 6 Dual
3
2
1
>=500,000
per quarter
8 Dual
3
3
2
1 All systems must monitor during
				  month of highest DBP concentrations
2 Systems on quarterly monitoring
				  must take dual sample sets every 90 days at each monitoring location, except
				  for surface water and GWUDI systems serving 500-3,300. Ground water systems
				  serving 500-9,999 on annual monitoring must take dual sample sets at each
				  monitoring location. All other systems on annual monitoring and surface water
				  and GWUDI 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 highest TTHM and HAA5 concentrations occur at the same location, and
				  month.
008.03 Systems must
				recommend 179 NAC 24 compliance monitoring locations based on standard
				monitoring results, system specific study results, and 179 NAC 16 or 24
				compliance monitoring results. Systems must follow the protocol in 179 NAC
				23-008.03A through
				23-008.03H. If
				required to monitor at more than eight locations, a system must repeat the
				protocol as necessary. If the system does not have existing 179 NAC 16 or 24
				compliance monitoring results or if it does not have enough existing 179 NAC 16
				or 24 compliance monitoring results, it must repeat the protocol, skipping the
				provisions of 179 NAC
				23-008.03C and
				23-008.03G as
				necessary, until it has identified the required total number of monitoring
				locations.
23-008.03A Location with the
				highest TTHM LRAA not previously selected as a 179 NAC 24 monitoring
				location.
23-008.03B Location with
				the highest HAA5 LRAA not previously selected as a 179 NAC 24 monitoring
				location.
23-008.03C Existing 179
				NAC 16 average residence time compliance monitoring location (maximum residence
				time compliance monitoring location for ground water systems) with the highest
				HAA5 LRAA not previously selected as a 179 NAC 24 monitoring
				location.
23-008.03D Location with
				the highest TTHM LRAA not previously selected as a 179 NAC 24 monitoring
				location.
23-008.03E Location with
				the highest TTHM LRAA not previously selected as a 179 NAC 24 monitoring
				location.
23-008.03F Location with
				the highest HAA5 LRAA not previously selected as a 179 NAC 24 monitoring
				location.
23-008.03G Existing 179
				NAC 16 average residence time compliance monitoring location (maximum residence
				time compliance monitoring location for ground water systems) with the highest
				TTHM LRAA not previously selected as a 179 NAC 24 monitoring
				location.
23-008.03H Location with
				the highest HAA5 LRAA not previously selected as a 179 NAC 24 monitoring
				location.