Nebraska Administrative Code › Topic - HEALTH AND HUMAN SERVICES SYSTEM › Title 179 - PUBLIC WATER SYSTEMS › Chapter 3 - MONITORING AND ANALYTICAL REQUIREMENTS › Section 179-3-007 - ORGANIC CHEMICALS OTHER THAN DISINFECTION BYPRODUCTS SAMPLING AND ANALYTICAL REQUIREMENTS

Current through June 17, 2024
007.01 Analyses for
				the contaminants in 179 NAC 3-007 must be conducted using the methods found in
				40 CFR
				141.24(e).
007.02 Monitoring Requirements
Monitoring for the contaminants listed in 179 NAC
				  2-002.04B1 (VOC)
				  for purposes of determining compliance with the maximum contaminant levels must
				  be conducted as follows.
3-007.02A
Ground Water Sources
: Ground water sources must be
				monitored at every entry point to the distribution system which is
				representative of each ground water source after treatment (hereafter called a
				sampling point or entry point). Each sample must be taken at the same sampling
				point unless conditions make another sampling point more representative of each
				source, treatment plant, or within the distribution system.
3-007.02B
Surface Water
				Sources
: Surface water sources (or combined surface/ground water
				sources) must take a minimum of one sample at points in the distribution system
				that are representative of each source or at each entry point to the
				distribution system after treatment (hereafter called a sampling point or entry
				point). Each sample must be taken at the same sampling point unless conditions
				make another sampling point more representative of each source, treatment
				plant, or within the distribution system.
3-007.02C
Multiple
				Sources
: If an entry point represents more than one source and the
				sources are combined before distribution, the system owner must sample at an
				entry point to the distribution system during periods of normal operating
				conditions (i.e., when water representative of all sources is being
				used).
3-007.02D
Monitoring Frequency
: Each community and non-transient,
				non-community water system must take four consecutive quarterly samples for
				each contaminant listed in 179 NAC
				2-002.04B during
				each compliance period, beginning in the initial compliance period.
3-007.02E
If No Contaminant Is
				Detected
: If the initial monitoring for contaminants listed in 179
				NAC
				2-002.04B1 (1) through
				(8) and the monitoring for the contaminants
				listed in 179 NAC
				2-002.04B1 (9) through
				(21) was completed by December 31, 1992, and
				the system did not detect any contaminant listed in 179 NAC
				2-002.04B1 (1) through
				(21), then each ground and surface water
				system must take one sample annually beginning with the initial compliance
				period.
3-007.02F
Reduced VOC Monitoring
: After a minimum of three years
				of annual sampling, the Director may allow ground water systems with no
				previous detection of any contaminant listed in 179 NAC
				2-002.04B1 to take
				one sample during each compliance period.
3-007.02G
Waiver
:
				The owner of each community and non-transient, non-community ground water entry
				point, at which no contaminant listed in 179 NAC
				2-002.04B1 is
				detected, may apply to the Director for a waiver from the requirements of 179
				NAC
				3-007.02E and
				3-007.02F after
				completing the initial monitoring. (For the purposes of 179 NAC
				3-007.02G,
				detection is defined as >= 0.0005 mg/L.) A waiver will be effective for no
				more than six years (two compliance periods). The Director may also issue
				waivers to small systems for the initial round of monitoring for
				1,2,4-trichlorobenzene.
3-007.02H
Bases of a Sampling Waiver
: The Director may grant a
				waiver after evaluating the following factor(s):
1. Knowledge of previous use (including
				transport, storage, or disposal) of the contaminant within the watershed or
				zone of influence of the 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.
2. If
				previous use of the contaminant is unknown or it has been used previously, then
				the following factors must be used to determine whether a waiver is granted:
a. Previous analytical results;
b. The proximity of the sources for the entry
				point to a potential point or non-point 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);
c. The environmental
				persistence and transport of the contaminants;
d. The number of individuals served by the
				public water system and the proximity of a small system to a larger
				system;
e. How well the water
				source is protected against contamination, such as whether it is a surface or
				ground water system. (For ground water sources, the Director will consider
				factors such as depth of the well, the type of soil, and wellhead protection.
				For surface water sources, the Director will consider watershed
				protection.)
3-007.02I As a condition of the waiver, the
				owner of a ground water system must take one sample at an entry point which
				received a waiver during the time the waiver is effective (i.e., one sample
				during two compliance periods or six years) and update its vulnerability
				assessment considering the factors listed in 179 NAC
				3-007.02H. Based
				on this vulnerability assessment, the Director will reconfirm that the entry
				point is non-vulnerable. If the Director does not make this reconfirmation
				within three years of the initial determination, then the waiver is
				invalidated.
3-007.02J The owner of
				each community and non-transient, non-community surface water entry point, at
				which no contaminant listed in 179 NAC
				2-002.04B1 is
				detected, may apply to the Director for a waiver from the requirements of 179
				NAC
				3-007.02E after
				monitoring at least one time. (For the purposes of this section, detection is
				defined as >= 0.0005 mg/L.) Composite samples from a maximum of five
				sampling points are allowed, provided that the detection limit of the method
				used for analysis is less than one-fifth of the MCL. Entry points meeting this
				criterion must be determined by the Director to be non-vulnerable based on a
				vulnerability assessment during each compliance period. Each system receiving a
				waiver must sample at the frequency specified by the Director (if
				any).
3-007.02K If a contaminant in
				179 NAC
				2-002.04B1 (1) through
				(21) is detected at a level exceeding 0.0005
				mg/L in any sample, for the first time, then:
1. The owner of the system must monitor
				quarterly at each sampling point which resulted in a detection.
2. The Director may decrease the quarterly
				monitoring requirement specified in 179 NAC
				3-007.02K item 1
				provided it has determined that the system is reliably and consistently below
				the maximum contaminant level. In no case will the Director make this
				determination unless a ground water system takes a minimum of two quarterly
				samples and a surface water system takes a minimum of four quarterly
				samples.
3. If the Director
				determines that the system is reliably and consistently below the MCL, the
				Director may allow the system to monitor annually. Systems that monitor
				annually must monitor during the quarter(s) that previously yielded the highest
				analytical result.
4. Systems that
				have three consecutive annual samples with no detection of a contaminant may
				apply to the Director for a waiver as specified in 179 NAC
				3-007.02G.
5.
Vinyl Chloride
				Monitoring
: Analysis for vinyl chloride is required only for
				ground water systems that have detected one or more of the following two-carbon
				organic compounds: Trichloroethylene, tetrachloroethylene, 1,2-dichloroethane,
				1,1,1-trichloroethane, cis-1,2-dichloroethylene, trans-1, dichloroethylene, or
				1,1-dichloroethylene. The analysis for vinyl chloride is required at each
				distribution or entry point at which one or more of the two-carbon organic
				compounds were found. If the first analysis does not detect vinyl chloride, the
				Director may reduce the frequency of vinyl chloride monitoring to one every
				three years for that sample location or other sample locations which are more
				representative of the same source. Surface water systems may be required to
				analyze for vinyl chloride at the discretion of the Director.
3-007.02L Entry points which
				violate the requirements of 179 NAC
				2-002.04B1, as
				determined by 179 NAC
				3-007.02O, must
				monitor quarterly. After a minimum of four consecutive quarterly samples which
				show the entry point is in compliance and the Director determines that the
				entry point is reliably and consistently below the maximum contaminant level,
				the owner of the entry point may monitor at the frequency and time specified in
				179 NAC
				3-007.02K item
				3.
3-007.02M The Director may
				require confirmation samples for positive or negative results. If a
				confirmation sample(s) is required by the Director, then the sample result(s)
				must be averaged with the first sampling result and the average used for
				compliance determination in accordance with 179 NAC
				3-007.02O. The
				Director has discretion to delete results of obvious sampling errors from this
				calculation.
3-007.02N
Composite Samples
: The Director may reduce the total
				number of samples a system must analyze by allowing the use of compositing.
				Composite samples from a maximum of five sampling points are allowed, provided
				that the detection limit of the method used for analysis is less than one-fifth
				of the MCL. Compositing of samples is to be done in the laboratory by the
				procedures listed below. Samples must be analyzed within 14 days of collection.
1. If the concentration in the composite
				sample is greater than or equal to 0.0005 mg/L for any contaminant listed in
				179 NAC
				2-002.04B1, then a
				follow-up sample must be taken and analyzed within 14 days from each sampling
				point included in the composite.
2.
				If duplicates of the original sample taken from each sampling point used in the
				composite are available, the system owner may use these duplicates instead of
				resampling. The duplicate must be analyzed within 14 days of
				collection.
3. If the population
				served by the system is greater than 3,300 individuals, then compositing may
				only be permitted at sampling points within a single system. In systems serving
				less than or equal to 3,300 individuals, compositing among different systems is
				allowed provided the 5-sample limit is maintained.
4.
Compositing Samples prior to
				GC Analysis
a. Add 5 ml or equal
				larger amounts of each sample (up to 5 samples are allowed) to a 25 ml glass
				syringe. Special precautions must be made to maintain zero headspace in the
				syringe.
b. The samples must be
				cooled at 4°C during this step to minimize volatilization losses.
c. Mix well and draw out a 5-ml aliquot for
				analysis.
d. Follow sample
				introduction, purging and desorption steps described in the method.
e. If less than five samples are used for
				compositing, a proportionately smaller syringe may be used.
5.
Compositing Samples
				Prior to GC/MS Analysis
a.
				Inject 5-ml or equal larger amounts of each aqueous sample (up to 5 samples are
				allowed) into a 25-ml purging device using the sample introduction technique
				described in the method.
b. The
				total volume of the sample in the purging device must be 25 ml.
c. Purge and desorb as described in the
				method.
3-007.02O
Compliance
				Calculations
: Compliance with the MCL in 179 NAC
				2-002.04B1 will be
				determined based on the analytical results obtained at each sampling point. If
				one sampling point is in violation of an MCL, the system is in violation of the
				MCL.
1. For systems monitoring more than once
				per year, compliance with the MCL is determined by a running annual average at
				each sampling point.
2. Systems
				monitoring annually or less frequently whose sample result exceeds the MCL must
				begin quarterly sampling. The system will not be considered in violation of the
				MCL until it has completed one year of quarterly sampling.
3. If any sample result will cause the
				running annual average to exceed the MCL at any sampling point, the system is
				out of compliance with the MCL 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 a sample result is
				less than the detection limit, zero will be used to calculate the annual
				average.
3-007.02P
Certified and Approved Laboratories
: Analysis under
				179 NAC 3-007 must only be conducted by the Department of Health and Human
				Services Public Health Environmental Laboratory or other laboratories that are
				certified by the Department or EPA according to the following conditions.
1. To receive certification to conduct
				analyses for the contaminants in 179 NAC
				2-002.04B1 (2) through
				(21), the laboratory must:
a. Analyze Performance Evaluation (PE)
				samples which include these substances provided by EPA Environmental Monitoring
				and Support Laboratory or equivalent samples provided by the Director at least
				once a year by each method for which the lab desires certification.
b. Achieve the following quantitative
				acceptance limits under 179 NAC
				3-007.02P items
				1.c. and 1.d. for at least 80% of the regulated organic chemicals included in
				the PE sample.
c. Achieve
				quantitative results on the analyses performed under 179 NAC
				3-007.02P item
				1.a. that are within ±20% of the actual amount of the substances in the
				Performance Evaluation sample when the actual amount is greater than or equal
				to 0.010 mg/L.
d. Achieve
				quantitative results on the analyses performed under 179 NAC
				3-007.02P item
				1.a. that are within ±40% of the actual amount of the substances in the
				Performance Evaluation sample when the actual amount is less than 0.010
				mg/L.
e. Achieve a method detection
				limit of 0.0005 mg/L, according to the procedures in Appendix B to Part 136 of
				the Code of Federal Regulations.
2. To receive certification to conduct
				analyses for vinyl chloride, the laboratory must:
a. Analyze Performance Evaluation (PE)
				samples provided by EPA Environmental Monitoring and Support Laboratory or
				equivalent samples provided by the Director at least once a year by each method
				for which the laboratory desires certification.
b. Achieve quantitative results on the
				analyses performed under 179 NAC
				3-007.02P item
				2.a. that are within ±40% of the actual amount of vinyl chloride in the
				Performance Evaluation sample.
c.
				Achieve a method detection limit of 0.0005 mg/L, according to the procedures in
				Appendix B to Part 136 of the Code of Federal Regulations.
d. Obtain certification for the contaminants
				listed in 179 NAC
				2-002.04B1 (2) through
				(21).
3-007.02Q The Director may increase required
				monitoring where necessary to detect variations within the system.
3-007.02R
Laboratory
				Certification
: Each approved laboratory must determine the method
				detection limit (MDL), (as defined in Appendix B to Part 136 of the Code of
				Federal Regulations. at which it is capable of detecting VOCs. The acceptable
				MDL is 0.0005 mg/L. This concentration is the detection concentration for
				purposes of 179 NAC 3-007.
3-007.02S
State Designated VOC
				Sampling Schedules
: Each public water system owner must monitor at
				the time designated by the Director within each compliance period.
3-007.02T
New Systems Or
				Sources
: All new systems or systems that use a new source of water
				that begin operation after January 22, 2004 must demonstrate compliance with
				the MCL within a period of time specified by the Director. The system must also
				comply with the initial sampling frequencies specified by the Director to
				ensure a system can demonstrate compliance with the MCL. Routine and increased
				monitoring frequencies must be conducted in accordance with the requirements in
				179 NAC 3-007.