Iowa Administrative Code › Agency 567 - Environmental Protection Commission › Title II - Air Quality › Division B › Chapter 41 - Water Supplies › Rule 567-41.5 - Organic Chemicals

Current through Register Vol. 47, No. 3, July 24, 2024
(1)
MCLs and other requirements for organic chemicals.
Maximum
				  contaminant levels for two classes of organic chemical contaminants specified
				  in 41.5(1)
"b"
apply to community water systems and
				  nontransient noncommunity water systems as specified herein. The two referenced
				  organic chemical classes are volatile organic chemicals (VOCs) and synthetic
				  organic chemicals (SOCs).
The requirements also contain analytical method
					 requirements and monitoring requirements referenced in
					 41.5(1)
"b"
and
"c."
Best available technology
					 (BAT) for control of these organic contaminants is referenced in 567-paragraph
					 43.3(10)
"a. "
a.
Applicability.
The maximum contaminant levels for volatile
				  and synthetic organic contaminants apply to community and nontransient
				  noncommunity water systems. Compliance with the volatile and synthetic organic
				  contaminant maximum contaminant level is calculated pursuant to
				  41.5(1)
"b. "
b.
Maximum contaminant levels (MCLs) and analytical methodology for
				  organic compounds.
The maximum contaminant levels for organic
				  chemicals are listed in the table in subparagraph 41.5(1)
"b"
(1). Analyses for the contaminants in this subrule shall be conducted using the
				  following methods, or their equivalent as approved by EPA. For analysis of a
				  compliance sample, a certified laboratory must be able to achieve at least the
				  method detection limit for the specific contaminant as listed in the following
				  table.
(1) Table:
ORGANIC CHEMICAL CONTAMINANTS, CODES, MCLS, ANALYTICAL
					 METHODS, AND DETECTION LIMITS
Contaminant
EPA
Contaminant
Code
MCL (mg/L)
Methodology1
Detection Limit
(mg/L)
Volatile Organic Chemicals (VOCs):
Benzene
2990
0.005
502.2, 524.2, 524.3,
								  524.47
0.0005
Carbon tetrachloride
2982
0.005
502.2, 524.2, 524.3,
								  524.47, 551.1
0.0005
Chlorobenzene (mono)
2989
0.1
502.2, 524.2, 524.3,
								  524.47
0.0005
1,2-Dichlorobenzene (ortho)
2968
0.6
502.2, 524.2, 524.3,
								  524.47
0.0005
1,4-Dichlorobenzene (para)
2969
0.075
502.2, 524.2, 524.3,
								  524.47
0.0005
1,2-Dichloroethane
2980
0.005
502.2, 524.2, 524.3,
								  524.47
0.0005
1,1-Dichloroethylene
2977
0.007
502.2, 524.2, 524.3,
								  524.47
0.0005
cis- 1,2-Dichloroethylene
2380
0.07
502.2, 524.2,524.3,
								  524.47
0.0005
trans-1,2-Dichloroethylene
2979
0.1
502.2, 524.2,524.3,
								  524.47
0.0005
Dichloromethane
2964
0.005
502.2, 524.2, 524.3,
								  524.47
0.0005
1,2-Dichloropropane
2983*
0.005
502.2, 524.2,524.3,
								  524.47
0.0005
Ethylbenzene
2992
0.7
502.2, 524.2,524.3,
								  524.47
0.0005
Styrene
2996
0.1
502.2, 524.2, 524.3,
								  524.47
0.0005
Tetrachloroethylene
2987
0.005
502.2, 524.2,
								  524.3,524.47, 551.1
0.0005
Toluene
2991
1
502.2, 524.2,524.3,
								  524.47
0.0005
1,1,1-Trichloroethane
2981
0.2
502.2, 524.2, 524.3,
								  524.47, 551.1
0.0005
Trichloroethylene
2984
0.005
502.2, 524.2, 524.3,
								  524.47, 551.1
0.0005
1,2,4-Trichlorobenzene
2378
0.07
502.2, 524.2, 524.3,
								  524.47
0.0005
1,1,2-Trichloroethane
2985
0.005
502.2, 524.2, 524.3,
								  524.47, 551.1
0.0005
Vinyl chloride
2976
0.002
502.2, 524.2, 524.3,
								  524.47
0.0005
Xylenes (total)
2955*
10
502.2, 524.2, 524.3,
								  524.47
0.0005
Synthetic Organic Chemicals (SOCs):
Alachlor3
2051
0.002
505, 507, 508.1, 525.2, 525.3,551.1
0.0002
Aldicarb
2047
0.003
531.1,6610
0.0005
Aldicarb sulfone
2044
0.002
531.1,6610
0.0008
Aldicarb sulfoxide
2043
0.004
531.1,6610
0.0005
Atrazine3
2050
0.003
505, 507, 508.1, 523, 525.2,525.3,536,551.1,
								  Syngenta AG-6255
0.0001
Benzo(a)pyrene
2306
0.0002
525.2,525.3,550,550.1
0.00002
Carbofuran
2046
0.04
531.1, 531.2, 6610, 6610B, 6610
								  B-042
0.0009
Chlordane3
2959
0.002
505, 508, 508.1, 525.2, 525.3
0.0002
2,4-D6(as acids,
								  salts, and esters)
2105
0.07
515.1, 515.2, 515.3, 515.4, 555, D5317-93, 98
								  (Reapproved 2003), 6610B, 6640-B, 6640 B-01, 6640 B-06
0.0001
Dalapon
2031
0.2
515.1, 515.3, 515.4, 552.1,552.2,552.3,557, 6640,
								  6610B, 6640-B, 6640 B-01, 6640 B-06
0.001
1,2-Dibromo-3-chloropropane (DBCP)
2931
0.0002
504.1,524.3, 551.1
0.00002
Di(2-ethylhexyl)adipate
2035
0.4
506, 525.2, 525.3
0.0006
Di(2-ethylhexyl)phthalate
2039
0.006
506, 525.2, 525.3
0.0006
Dinoseb6
2041
0.007
515.1, 515.2, 515.3, 515.4, 555, 6610B, 6640-B,
								  6640 B-01, 6640 B-06
0.0002
Diquat
2032
0.02
549.2
0.0004
Endothall
2033
0.1
548.1
0.009
Endrin3
2005
0.002
505, 508, 508.1, 525.2, 525.3,551.1
0.00001
Ethylene dibromide (EDB)
2946
0.00005
504.1,524.3, 551.1
0.00001
Glyphosate
2034
0.7
547, 6651, 6651B, 6651 B-00, 6640 B-05
0.006
Heptachlor3
2065
0.0004
505, 508, 508.1, 525.2, 525.3,551.1
0.00004
Heptachlor
								  epoxide3
2067
0.0002
505, 508, 508.1, 525.2, 525.3,551.1
0.00002
Hexachlorobenzene3
2274
0.001
505, 508, 508.1, 525.2, 525.3,551.1
0.0001
Hexachlorocyclopentadiene3
2042
0.05
505, 508, 508.1, 525.2, 525.3,551.1
0.0001
Lindane (gamma
								  BHC)3
2010
0.0002
505, 508, 508.1, 525.2, 525.3,551.1
0.00002
Methoxychlor3
2015
0.04
505, 508, 508.1, 525.2, 525.3,551.1
0.0001
Oxamyl
2036
0.2
531.1, 531.2, 6610, 6610B, 6610
								  B-042
0.002
Pentachlorophenol
2326
0.001
515.1, 515.2, 515.3, 515.4, 525.2, 525.3, 555,
								  D5317-93, 98 (Reapproved 2003), 6610B, 6640-B, 6640 B-01, 6640 B-06
0.00004
Picloram3. 
								  6
2040
0.5
515.1, 515.2, 515.3, 515.4, 555, D5317-93, 98
								  (Reapproved 2003), 6610B, 6640-B, 6640 B-01, 6640 B-06
0.0001
Polychlorinated biphenyls4
									 (as decachlorobiphenyl) (as
								  Arochlors)3
2383
0.0005
508A
505, 508, 508.1, 525.2, 525.3
0.0001
Simazine3
2037
0.004
505, 507, 508.1, 523,
								  525.2,525.3,536,551.1
0.00007
2,3,7,8-TCDD (dioxin)
2063
3xl0-8
1613
5xl0"9
2,4,5-TP6(Silvex)
2110
0.05
515.1, 515.2, 515.3, 515.4, 555, D5317-93, 98
								  (Reapproved 2003), 6610B, 6640-B, 6640 B-01, 6640 B-06
0.0002
Toxaphene3
2020
0.003
505, 508, 508.1, 525.2, 525.3
0.001
*As of January 1, 1999, the contaminant codes for the
					 following compounds were changed from the Iowa Contaminant Code to the EPA
					 Contaminant Code:
Contaminant
Iowa Contaminant Code (Old)
EPA Contaminant Code (New)
1,2 Dichloropropane
2325
2983
Xylenes (total)
2974
2955
1Analyses for the contaminants
					 in this section shall be conducted using the following EPA methods or their
					 equivalent as approved by EPA. This incorporation by reference was approved by
					 the Director of the Federal Register in accordance with
					 5
					 U.S.C. 552(a) and
					 1 CFR Part 51. Copies
					 may be inspected at EPAs Drinking Water Docket, EPA West, 1301 Constitution
					 Avenue, NW, Room 3334, Washington, DC 20460 (telephone: (202)566-2426); or at
					 the National Archives and Records Administration (NARA). For information on the
					 availability of this material at NARA, call (202)741-6030, or via Internet at
					 www.archives.gov/federalregister/code_of
					 federal_regulations/ibr_locations.html.
The following methods are available from the National
					 Technical Information Service, U.S. Department of Commerce, 5285 Port Royal
					 Road, Springfield, VA 22161 (telephone: (800)553-6847).
Methods for the Determination of Organic Compounds in
					 Drinking Water, EPA-600/4-88-039, December 1988, Revised July 1991 (NTIS
					 PB91-231480): Methods 508A and 515.1.
Methods for the Determination of Organic Compounds in
					 Drinking Water-Supplement I, EPA-600/4-90-020, July 1990 (NTIS PB91-146027):
					 Methods 547, 550, 550.1.
Methods for the Determination of Organic Compounds in
					 Drinking Water-Supplement II, EPA-600/R-92-129, August 1992 (NTIS PB92-207703):
					 Methods 548.1, 552.1, 555.
Methods for the Determination of Organic Compounds in
					 Drinking Water-Supplement III, EPA-600/R-95-131, August 1995 (NTIS
					 PB95-261616): Methods 502.2, 504.1, 505, 506, 507, 508, 508.1, 515.2, 524.2,
					 525.2, 531.1, 551.1, 552.2.
EPA Method 523, "Determination of Triazine Pesticides and
					 Their Degradates in Drinking Water by Gas Chromatography/Mass Spectrometry
					 (GC/MS)," 2011. EPA-815-R-11-002. Available at www.nepis.epa.gov .
EPA Method 524.3, Version 1.0. "Measurement of Purgeable
					 Organic Compounds in Water by Capillary Column Gas Chromatography/Mass
					 Spectrometry," June 2009. EPA 815-B-09-009. Available at www.nemi.gov .
EPA Method 525.3, "Determination of Semivolatile Organic
					 Chemicals in Drinking Water by Solid Phase Extraction and Capillary Column Gas
					 Chromatograph/Mass Spectrometry (GC/MS)," 2012. EPA/600/R-12-010. Available at
					 www.nepis.epa.gov .
EPA Method 536, "Determination of Triazine Pesticides and
					 Their Degradates in Drinking Water by Liquid Chromatography Electrospray
					 Ionization Tandem Mass Spectrometry (LC/ESI-MS/MS)," 2007. EPA/815-B-07-002.
					 Available at www.nepis.epa.gov .
EPA Method 557, "Determination of Haloacetic Acids,
					 Bromate, and Dalapon in Drinking Water by Ion Chromatography Electrospray
					 Ionization Tandem Mass Spectrometry (IC-ESI-MS/MS)," September 2009. EPA
					 815-B-09-012. Available at www.nemi.gov .
Method 1613 "Tetra-through Octa-Chlorinated Dioxins and
					 Furans by Isotope-Dilution HRGC/HRMS," EPA-821-B-94-005, October 1994 (NTIS
					 PB95-104774).
The following American Public Health Association (APHA)
					 documents are available from APHA, 800 I Street, NW, Washington, DC
					 20001-3710.
Supplement to the 18th Edition of Standard Methods for the
					 Examination of Water and Wastewater, 1994, Standard Methods for the Examination
					 of Water and Wastewater, 19th edition, 1995, 20th edition, 1998, 21st edition,
					 2005, or 22nd edition, 2012 (any of these editions may be used), APHA: Method
					 6610 and (carbofuran and oxamyl only) 6610B and 6610 B-04; Method 6640B (21st
					 and 22nd editions only) and SM online 6640 B-01 for 2,4-D, 2,4,5-TP Silvex,
					 dalapon, dinoseb, pentachlorophenol, and picloram; Method 6651B (21st and 22nd
					 editions only) and SM online 6670-B-00 for glyphosate.
Standard Methods for the Examination of Water and
					 Wastewater, 18th edition, 1992, 19th edition, 1995, or 20th edition, 1998, (any
					 of these editions may be used), APHA: Method 6651.
The following American Society for Testing and Materials
					 (ASTM) method is available from ASTM International, 100 Barr Harbor Drive, West
					 Conshohocken, PA 19428.
Annual book of ASTM Standards, 1999, Vol. 11.02 (or any
					 edition published after 1993), ASTM: D5317-93, 98 (Reapproved 2003).
Methods 515.3 and 549.2 are available from U.S. EPA NERL,
					 26 W. Martin Luther King Drive, Cincinnati, OH 45268.
Method 515.4, "Determination of Chlorinated Acids in
					 Drinking Water by Liquid-Liquid Microextraction, Derivatization and Fast Gas
					 Chromatography with Electron Capture Detection," Revision 1.0, April 2000, EPA
					 815/B-00/001 and EPA Method 552.3, "Determination of Haloacetic Acids and
					 Dalapon in Drinking Water by Liquid-liquid Microextraction, Derivatization, and
					 Gas Chromatography with Electron Capture Detection," Revision 1.0, July 2003,
					 EPA 815-B-03-002, available at www.epa.gov/safewater/methods/sourcalt.html
					 .
Method 531.2, "Measurement of n-Methylcarbamoyloximes and
					 n-Methylcarbamates in Water by Direct Aqueous Injection HPLC with Postcolumn
					 Derivatization," Revision 1.0, September 2001, EPA 815/B-01/002, available at
					 www.epa.gov/safewater/methods/sourcalt.html .
Syngenta AG-625 Method, "Atrazine in Drinking Water by
					 Immunoassay," February 2001, is available from Syngenta Crop Protection, Inc.,
					 410 Swing Road, P.O. Box 18300, Greensboro, NC 27419, telephone
					 (336)632-6000.
Other required analytical test procedures germane to the
					 conduct of these analyses are contained in Technical Notes on Drinking Water
					 Methods, EPA-600/R-94-173, October 1994 (NTIS PB95-104766).
2Standard Methods Online is
					 available at www.standardmethods.org. The year in which each method was
					 approved by the Standard Methods Committee is designated by the last two digits
					 in the method number. The methods listed are the only online versions that may
					 be used.
3Substitution of the detector
					 specified in Method 505, 507, 508, or 508.1 for the purpose of achieving lower
					 detection limits is allowed as follows. Either an electron capture or
					 nitrogen-phosphorus detector may be used provided all regulatory requirements
					 and quality control criteria are met.
4PCBs are qualitatively
					 identified as Aroclors and measured for compliance purposes as
					 decachlorobiphenyl. Users of Method 505 may have more difficulty in achieving
					 the required detection limits than users of Method 508. 508.1, or 525.2.
5This method may not be used for
					 the analysis of atrazine in any system where chlorine dioxide is used in the
					 drinking water treatment. In samples from all other systems, any result for
					 atrazine generated by Method AG-625 that is greater than one-half the MCL
					 (i.e., greater than 0.0015 mg/L) must be confirmed using another approved
					 method for this contaminant and should use additional volume of the original
					 sample collected for compliance monitoring. In instances where a result from
					 Method AG-625 triggers such confirmatory testing, the confirmatory result is to
					 be used to determine compliance.
6Accurate determination of the
					 chlorinated esters requires hydrolysis of the sample as described in EPA
					 Methods 515.1, 515.2, 515.3, 515.4, and 555, and ASTM Method D5317-93, 98
					 (Reapproved 2003).
7EPA Method 524.4, Version 1.0.
					 "Measurement of Purgeable Organic Compounds in Water by Gas Chromatography/Mass
					 Spectrometry Using Nitrogen Purge Gas," May 2013, EPA
					 815-R-13-002.
(2) Organic
				  chemical compliance calculations. Compliance with 41.5(1)
"b"
"(1)"shall be determined based on the analytical results obtained at each
				  sampling point. If one sampling point is in violation of an MCL listed in
				  41.5(1)
"b"
(1), the system is in violation of the MCL. If a
				  system fails to collect the required number of samples, compliance will be
				  based on the total number of samples collected. If a sample result is less than
				  the detection limit, zero will be used when calculating the running annual
				  average. If the system is in violation of an MCL, the water supplier is
				  required to give notice to the department in accordance with 567-subrule
				  42.4(1) and to notify the public as required by
				  567-421. (455B).
1. Systems monitoring more than once per year
				  for VOC or SOC contaminants. For systems which monitor more than once per year,
				  compliance with the MCL is determined by a running annual average of all
				  samples collected at each sampling point.
2. Systems monitoring annually or less
				  frequently for VOC contaminants. Systems which monitor annually or less
				  frequently and whose VOC 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. However, if any sample result
				  will cause the running annual average to exceed the MCL at any sampling point,
				  the system is immediately out of compliance with the MCL.
3. Systems monitoring annually or less
				  frequently for SOC contaminants. Systems which monitor annually or less
				  frequently and whose SOC sample result exceeds the regulatory detection limit
				  specified in subparagraph 41.5(1)
"b"
(1) must begin quarterly
				  sampling. The system will not be considered in violation of the MCL until it
				  has completed one year of quarterly sampling. However, if any sample result
				  will cause the running annual average to exceed the MCL at any sampling point,
				  the system is immediately out of compliance with the MCL.
(3) Treatment techniques for acrylamide and
				  epichlorohydrin. Each public water supply system must certify annually in
				  writing to the department (using third-party or manufacturer's certification)
				  that when acrylamide and epichlorohydrin are used in drinking water systems,
				  the combination (or product) of dose and monomer level does not exceed the
				  levels specified as follows:
Acrylamide = 0.05% dosed at 1 ppm (or equivalent)
Epichlorohydrin = 0.01% dosed at 20 ppm (or equivalent)
					 Certifications can rely on information provided by manufacturers or third
					 parties, as approved by the department.
c.
Organic chemical monitoring
				  requirements.
Each public water system shall monitor at the time
				  designated within each compliance period. All new systems or systems that use a
				  new source of water must demonstrate compliance with the MCLs within the time
				  period specified by the department. The system must also comply with the
				  initial sampling frequencies specified by the department to ensure the system
				  can demonstrate compliance with the MCLs. A source of water that is determined
				  by the department to be a new source/entry point is considered to be a new
				  source for the purposes of paragraph 41.5(1)
"c. "
Routine and
				  increased monitoring frequencies shall be conducted in accordance with the
				  requirements in this paragraph.
(1) Routine
				  volatile organic chemical (VOC) monitoring requirements. Beginning on January
				  1, 1993, community water supplies and NTNC water supplies shall conduct
				  monitoring of the contaminants listed in 41.5(1)
"b "
(1) for
				  the purpose of determining compliance with the maximum contaminant
				  level.
(2) VOC monitoring protocol.
1. VOC groundwater monitoring protocol.
				  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 source/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.
2. VOC surface water
				  monitoring protocol. Surface water systems (and combined surface/groundwater
				  systems) shall take a minimum of one sample at each entry point to the
				  distribution system after treatment (hereafter called a source/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.
				  Multiple sources. If the system draws water from more than one 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
				  (i.e., when water representative of all sources is being used). If a
				  representative sample of all water sources cannot be obtained, as determined by
				  the department, separate source/entry points with the appropriate monitoring
				  requirements will be assigned by the department.
4. Initial VOCs monitoring frequency. Each
				  community and nontransient noncommunity water system shall take four
				  consecutive quarterly samples for each contaminant listed in
				  41.5(1)
"b"
(1) during each compliance period, beginning in the
				  initial compliance period. If the initial monitoring for contaminants listed in
				  41.5(1)
"b"
(1) has been completed by December 31, 1992, and
				  the system did not detect any contaminant listed in
				  41.5(1)
"b",
(1) then each groundwater and surface water system
				  shall take one sample annually beginning with the initial compliance
				  period.
5. Reduced VOC monitoring
				  for groundwater systems. After a minimum of three years of annual sampling, the
				  department may allow groundwater systems with no previous detection of any
				  contaminant listed in 41.5(1)
"b"
(1) to take one sample during
				  each compliance period.
6. VOC
				  monitoring waivers. Each community and nontransient noncommunity groundwater
				  system which does not detect a contaminant listed in 41.5(1)
"b
"(1) may apply to the department for a waiver from the requirements of 41.5(1)
"c "
(2)"4" and "5" after completing the initial monitoring. A
				  waiver shall be effective for no more than six years (two compliance periods).
				  The department may also issue waivers to small systems for the initial round of
				  monitoring for 1,2,4-trichlorobenzene. Detection is defined as greater than or
				  equal to 0.0005 mg/L.
7. Bases of a
				  VOC monitoring waiver. The department may grant a waiver if the department
				  finds that there has not been any knowledge of previous use (including
				  transport, storage, or disposal) of the contaminant within the watershed or
				  zone of influence of the system. If previous use of the contaminant is unknown
				  or it has been used previously, then the following factors shall be used to
				  determine whether a waiver is granted.
* Previous analytical results.
* The proximity of the 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.
* The environmental persistence and transport of the
					 contaminants.
* The number of persons served by the public water system
					 and the proximity of a smaller system to a larger system, and
* How well the water source is protected against
					 contamination, such as whether it is a surface or groundwater system.
					 Groundwater systems must consider factors such as depth of the well, the type
					 of soil, and wellhead protection. Surface water systems must consider watershed
					 protection.
8. VOC
				  monitoring waiver requirements for groundwater systems. As a condition of the
				  waiver, a groundwater system must take one sample at each sampling point 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 41.5(1)
"c "
(2)"7." Based on this
				  vulnerability assessment the department must reconfirm that the system is
				  nonvulnerable. If the department does not reconfirm within three years of the
				  initial vulnerability determination, then the waiver is invalidated and the
				  system is required to sample annually as specified in 41.5(1)
"c
				  "
(2)"4."
9. VOC
				  monitoring waiver requirements for surface water systems. Each community and
				  nontransient noncommunity surface water system which does not detect a
				  contaminant listed in 41.5(1)
"b"
(1) may apply to the
				  department for a waiver from the requirements of 41.5(1)
"c
				  "
(2)"4" after completing the initial monitoring. Systems meeting this
				  criterion must be determined by the department to be nonvulnerable based on a
				  vulnerability assessment during each compliance period. Each system receiving a
				  waiver shall sample at the frequency specified by the department (if
				  any).
10. Increased VOC monitoring.
				  If a contaminant listed in 41.5(1)
"b"
(1) is detected at a
				  level exceeding 0.0005 mg/L in any sample, then:
The system must monitor quarterly at each sampling point
					 which resulted in a detection.
The department may decrease the quarterly monitoring
					 requirement specified in 41.5(1)
"c "
(2)"4" provided it has
					 determined that the system is reliably and consistently below the maximum
					 contaminant level. In no case shall the department 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.
If the department determines that the system is reliably
					 and consistently below the MCL, the department may allow the system to monitor
					 annually. Systems which monitor annually must monitor during the quarter(s)
					 which previously yielded the highest analytical result.
Systems which have three consecutive annual samples with no
					 detection of a contaminant may apply to the department for a waiver as
					 specified in 41.5(1)
"c "
(2)"6."
Groundwater systems which have detected one or more of the
					 following two-carbon organic compounds: trichloroethylene, tetrachloroethylene,
					 1,2-dichloroethane, 1,1,1-trichloroethane, cis-l,2-dichloroethylene,
					 trans-1,2-dichloroethylene, or 1,1-dichloroethylene shall monitor quarterly for
					 vinyl chloride. A vinyl chloride sample shall be taken at each sampling point
					 at which one or more of the two-carbon organic compounds was detected. If the
					 results of the first analysis do not detect vinyl chloride, the department may
					 reduce the quarterly monitoring frequency of vinyl chloride monitoring to one
					 sample during each compliance period. Surface water systems are required to
					 monitor for vinyl chloride as specified by the department.
11. VOCs reliably and consistently below the
				  MCL. Systems which violate the MCL requirements of 41.5(1)
"b"
(1) must monitor quarterly. After a minimum of four consecutive quarterly
				  samples which show the system is in compliance and the department determines
				  that the system is reliably and consistently below the maximum contaminant
				  level, the system may monitor at the frequency and times specified in 41.5(1)
"c "
(2)"10," third unnumbered paragraph (following approval by
				  the department).
(3)
				  Routine and repeat synthetic organic chemical (SOC) monitoring requirements.
				  Analysis of the synthetic organic contaminants listed in
				  41.5(1)
"b"
(1) for the purposes of determining compliance with
				  the maximum contaminant level shall be conducted as follows:
1. SOC groundwater monitoring protocols.
				  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 source/entry point). Each sample must be taken at the same
				  sampling point unless conditions make another sampling point more
				  representative of each source or treatment plant.
2. SOC surface water monitoring protocols.
				  Surface water systems shall take a minimum of one sample at each entry point to
				  the distribution system after treatment (hereafter called a source/entry
				  point). Each sample must be taken at the same sampling point unless conditions
				  make another sampling point more representative of each source or treatment
				  plant. For purposes of this paragraph, surface water systems include systems
				  with a combination of surface and ground sources.
3. Multiple sources. If the system draws
				  water from more than one 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 (i.e., when water
				  representative of all sources is being used). If a representative sample of all
				  water sources cannot be obtained, as determined by the department, separate
				  source/entry points with the appropriate monitoring requirements will be
				  assigned by the department.
4. SOC
				  monitoring frequency. Community and nontransient noncommunity water systems
				  shall take four consecutive quarterly samples for each contaminant listed in
				  41.5(1)
"b"
(1) during each compliance period beginning with
				  the compliance period starting January 1, 1993. Systems serving more than 3,300
				  persons which do not detect a contaminant in the initial compliance period may
				  reduce the sampling frequency to a minimum of two quarterly samples in one year
				  during each repeat compliance period. Systems serving less than or equal to
				  3,300 persons which do not detect a contaminant in the initial compliance
				  period may reduce the sampling frequency to a minimum of one sample during each
				  repeat compliance period.
5. SOC
				  monitoring waivers. Each community and nontransient water system may apply to
				  the department for a waiver from the requirements of 41.5(1)
"c
"(3)"4." A system must reapply for a waiver for each compliance
				  period.
6. Bases of an SOC
				  monitoring waiver. The department may grant a waiver if the department finds
				  that there has been no knowledge of previous use (including transport, storage,
				  or disposal) of the contaminant within the watershed or zone of influence of
				  the system. If previous use of the contaminant is unknown or it has been used
				  previously, then the department shall determine whether a waiver may be granted
				  by considering:
* Previous analytical results.
* The proximity of the 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, home and gardens, and other land application uses.
* The environmental persistence and transport of the
					 pesticide or PCBs.
* How well the water source is protected against
					 contamination due to such factors as depth of the well and the type of soil and
					 the integrity of the well casing.
* Elevated nitrate levels at the water supply source,
					 and
* Use of PCBs in equipment used in the production, storage,
					 or distribution of water (i.e., PCBs used in pumps and transformers).
7. Increased SOC monitoring. If a
				  synthetic organic contaminant listed in 41.5(1)
"b"
(1) is
				  detected in any sample, then:
* Each system must monitor quarterly at each sampling point
					 which resulted in a detection.
* The department may decrease the quarterly SOC monitoring
					 requirement if the system is reliably and consistently below the maximum
					 contaminant level. In no case shall the department 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.
* After the department determines the system is reliably
					 and consistently below the maximum contaminant level, the system may monitor
					 annually. Systems which monitor annually must monitor during the quarter that
					 previously yielded the highest analytical result.
* Systems which have three consecutive annual samples with
					 no detection of a contaminant may apply to the department for a waiver as
					 specified in 41.5(1)
"c "
(3)"6."
* If monitoring results in detection of one or more of
					 certain related contaminants (aldicarb, aldicarb sulfone, aldicarb sulfoxide,
					 heptachlor, and heptachlor epoxide), then subsequent monitoring shall analyze
					 for all related contaminants.
8. MCL violation and reliably/consistently
				  below the MCL. Systems which violate the requirements of 41.5(1)
"c"
must monitor quarterly. After a minimum of four quarterly samples
				  show the system is in compliance and the department determines the system is
				  reliably and consistently below the MCL, the system shall monitor at the
				  frequency specified in 41.5(1)
"c "
(3)"7."
(4) Organic chemical (SOC and VOC)
				  confirmation samples. The department may require a confirmation sample for
				  positive or negative results. If a confirmation sample is required by the
				  department, the result must be averaged with the first sampling result and the
				  average is used for the compliance determination as specified by
				  41.5(1)
"b "
(2). The department has discretion to disregard
				  results of obvious sampling errors from this calculation.
(5) Grandfathered organic chemical (SOC and
				  VOC) data. The department may allow the use of monitoring data collected after
				  January 1,1988, for VOCs and January 1,1990, for SOCs required under Section
				  1445 of the Safe Drinking Water Act for purposes of initial monitoring
				  compliance. If the data are generally consistent with the other requirements in
				  this subparagraph, the department may use such data (i.e., a single sample
				  rather than four quarterly samples) to satisfy the initial monitoring
				  requirement for the initial compliance period beginning January 1, 1993.
				  Systems which use grandfathered samples for VOCs and did not detect any
				  contaminants listed in 41.5(1)
"b"
(1) shall begin monitoring
				  annually in accordance with 41.5(1) "c "(2) beginning January 1,
				  1993.
(6) Increased organic
				  chemical (SOC and VOC) monitoring. The department may increase the required
				  monitoring frequency, where necessary, to detect variations within the system
				  (e.g., fluctuations in concentration due to seasonal use, changes in water
				  source, changes to treatment facilities or normal operation thereof).
(7) Organic chemical (SOC and VOC)
				  vulnerability assessment criteria. Vulnerability of each public water system
				  shall be determined by the department based upon an assessment of the following
				  factors.
1. VOC vulnerability assessment
				  criteria-previous monitoring results. A system will be classified vulnerable if
				  any sample was analyzed to contain one or more contaminants listed in
				  41.5(1)
"b"
(1)-(VOCs) or 41.5(1)
"b"
(3)
				  except for trihalomethanes or other demonstrated disinfection
				  by-products.
2. SOC vulnerability
				  assessment criteria-previous monitoring results. A system will be classified
				  vulnerable if any sample was analyzed to contain one or more contaminants
				  listed in 41.5(1)
"b"
(2)-(SOCs) or 41.5(1)
"b
"(3) except for trihalomethanes or other demonstrated disinfection
				  by-products.
3. Proximity of
				  surface water supplies to commercial or industrial use, disposal or storage of
				  volatile synthetic organic chemicals. Surface waters which withdraw water
				  directly from reservoirs are considered vulnerable if the drainage basin
				  upgradient and within two miles of the shoreline at the maximum water level
				  contains major transportation facilities such as primary highways or railroads
				  or any of the contaminant sources listed in this subparagraph. Surface water
				  supplies which withdraw water directly from flowing water courses are
				  considered vulnerable if the drainage basin upgradient and within two miles of
				  the water intake structure contains major transportation facilities such as
				  primary highways or railroads or any of the contaminant sources listed in this
				  subparagraph.
4. Proximity of
				  supplies to commercial or industrial use, disposal or storage of volatile
				  synthetic organic chemicals. Wells that are not separated from sources of
				  contamination by at least the following distances will be considered
				  vulnerable.
Sources of Contamination
Shallow Wells as defined in
								  567-402. (455B)
Deep Wells as defined in
								  567-402. (455B)
Sanitary and industrial point discharges
400 ft
400 ft
Mechanical waste treatment plants
400 ft
200 ft
Lagoons
1,000 ft
400 ft
Chemical and mineral storage (aboveground)
200 ft
100 ft
Chemical and mineral storage including
								  underground storage tanks on or below ground
400 ft
200 ft
Solid waste disposal site
1,000 ft
1,000 ft
5.
				  A system is deemed to be vulnerable for a period of three years after any
				  positive measurement of one or more contaminants listed in
				  41.5(1)
"b"
(1) except for trihalomethanes or other
				  demonstrated disinfection by-products.
(8) PCB analytical methodology. Analysis for
				  PCBs shall be conducted using the methods in 41.5
"b"
(1) and
				  as follows:
1. Each system which monitors for
				  PCBs shall analyze each sample using Method 505,508,508.1, or 525.2. Users of
				  Method 505 may have more difficulty in achieving the required Aroclor detection
				  limits than users of Method 508, 508.1, or 525.2.
2. If PCBs (as one of seven Aroclors) are
				  detected in any sample analyzed using Method 505 or 508, the system shall
				  reanalyze the sample using Method 508A to quantitate PCBs as decachlorobipheny.
PCB AROCLOR DETECTION
					 LIMITS
Aroclor
Detection Limit (mg/L)
1016
0.00008
1221
0.02
1232
0.0005
1242
0.0003
1248
0.0001
1254
0.0001
1260
0.0002
3.
				  Compliance with the PCB MCL shall be determined based upon the quantitative
				  results of analyses using Method 508A.
d.
Best available technology(ies)
				  (BATs).
Rescinded IAB 8/11/99, effective 9/15/99.
e.
Total trihalomeihanes sampling,
				  analytical and other requirements.
Rescinded IAB 1/7/04, effective
				  2/11/04.
f.
Analytical
				  procedures
-
organics.
Rescinded IAB 1/7/04, effective
				  2/11/04.