DEQ-CFW_00001342

Handout for Agenda Item # 2:
May 9, 2007 EMC Groundwater Committee Meeting
Section .0200 — Classifications and Groundwater Quality Standards
With the Appendix for the
Interim Maximum Allowable Concentrations
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SECTION .0200 - CLASSIFICATIONS AND GROUNDWATER QUALITY
STANDARDS
15A NCAC 02L .0201 GROUNDWATER CLASSIFICATIONS
The classifications which may be assigned to the groundwaters will be those specified in the
following series of classifications:
(1) Class GA groundwaters; usage and occurrence:
(a) Best Usage. Existing or potential source of drinking water supply for
humans.
(b) Conditions Related to Best Usage. This class is intended for those
groundwaters in which chloride concentrations are equal to or less than
250 mg/l, and which are considered suitable for drinking in their natural
state, but which may require treatment to improve quality related to
natural conditions.
(c) Occurrence. In the saturated zone.
(2) Class GSA groundwaters; usage and occurrence:
(a) Best Usage. Existing or potential source of water supply for potable
mineral water and conversion to fresh waters.
(b) Conditions Related to Best Usage. This class is intended for those
groundwaters in which the chloride concentrations due to natural
conditions is in excess of 250 mg/l, but which otherwise may be
considered suitable for use as potable water after treatment to reduce
concentrations of naturally occurring substances.
(c) Occurrence. In the saturated zone.
(3) Class GC groundwaters: usage and occurrence:
(a) Best Usage. The best usage of GC groundwaters is as a source of water
supply for purposes other than drinking, including other domestic uses by
humans.
(b) Conditions Related to Best Usage. This class includes those groundwaters
that do not meet the quality criteria for GA or GSA groundwaters and for
which efforts to improve groundwater quality would not be
technologically feasible, or not in the best interest of the public.
Continued consumption of waters of this class by humans could result in
adverse health affects.
(c) Occurrence. Groundwaters of this class may be defined by the
Commission pursuant to Section .0300 of this Subchapter on a case by
case basis.
History Note: Authority G.S. 143-214.1; 143B-282(2);
Eff. June 10, 1979;
Amended Eff. October 1, 1993; August 1, 1989; September 1., 1984; December
30, 1983.
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15A NCAC 02L .0202 GROUNDWATER QUALITY STANDARDS
(a) The groundwater quality standards for the protection of the groundwaters of the state are
those specified in this Rule. They are the maximum allowable concentrations resulting from any
discharge of contaminants to the land or waters of the state, which may be tolerated without
creating a threat to human health or which would otherwise render the groundwater unsuitable
for its intended best usage.
(b) The groundwater quality standards for contaminants specified in Paragraphs (g) and (h) of
this Rule shall be as listed, except that:
(1) Where the standard for a substance is less than the practical quantitation limit, the
detection of that substance at or above the practical quantitation limit shall
constitute a violation of the standard.
(2) Where two or more substances exist in combination, the Director shall consider
the effects of chemical interactions as determined by the Division of Public
Health and may establish maximum concentrations at values less than those
established in accordance with Paragraphs (c), (g), or (h) of this Rule. In the
absence of information to the contrary, in accordance with Paragraph (d) of this
Rule, the carcinogenic risks associated with carcinogens present shall be
considered additive and the toxic effects associated with non -carcinogens present
shall also be considered additive.
(3) Where naturally occurring substances exceed the established standard, the
standard shall be the naturally occurring concentration as determined by the
Director.
(c) Except for tracers used in concentrations which have been determined by the Division of
Public Health to be protective of human health, and the use of which has been permitted by the
Division, substances which are not naturally occurring and for which no standard is specified
shall not be permitted in detectable concentrations in Class GA or Class GSA groundwaters.
Any person may petition the Director to establish an interim maximum allowable concentration
for a substance for which a standard has not been established under this Rule. The petitioner
shall submit relevant toxicological and epidemiological data, study results, and calculations
necessary to establish a standard in accordance with Paragraph (d) of this Rule. Within three
months after the establishment of an interim maximum allowable concentration for a substance
by the Director, the Director shall initiate action to consider adoption of a standard for that
substance.
(d) Groundwater quality standards for substances in Class GA and Class GSA groundwaters are
established as the least of:
(1) Systemic threshold concentration calculated as follows: [Reference Dose
(mg/kg/day) x 70 kg (adult body weight) x Relative Source Contribution (.10 for
inorganics; .20 for organics)] / [2 liters/day (avg. water consumption)];
(2) Concentration which corresponds to an incremental lifetime cancer risk of 1x10"6;
(3) Taste threshold limit value;
(4) Odor threshold limit value;
(5) Maximum contaminant level; or
(6) National secondary drinking water standard.
(e) The following references, in order of preference, shall be used in establishing concentrations
of substances which correspond to levels described in Paragraph (d) of this Rule.
10)
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(1) Integrated Risk Information System (U.S. EPA).
(2) Health Advisories (U.S. EPA Office of Drinking Water).
(3) Other health risk assessment data published by U.S. EPA.
(4) Other appropriate, published health risk assessment data, and scientifically valid
peer -reviewed published toxicological data.
(f) Groundwater quality standards specified in Paragraphs (g) and (h) of this Rule and interim
maximum allowable concentrations established pursuant to Paragraph (c) of this Rule shall be
reviewed on a triennial basis. Appropriate modifications to established standards shall be made
in accordance with the procedure prescribed in Paragraph (d) of this Rule where modifications
are considered appropriate based on data published subsequent to the previous review.
(g) Class GA Standards. Where not otherwise indicated, the standard refers to the total
concentration in milligrams per liter of any constituent in a dissolved, colloidal or particulate
form which is mobile in groundwater. This does not apply to sediment or other particulate
matter which is preserved in a groundwater sample as a result of well construction or sampling
procedures.
(1)
acetone: 0.7
(2)
acenaphthene: 0.08
(3)
acenaphthylene: 0.21
(4)
acrylamide (propenamide): 0.000008
(5)
anthracene: 2.1
(6)
arsenic: 0.05
(7)
atrazine and chlorotriazine metabolites:
(8)
barium: 2.0
(9)
benzene: 0.001
(10)
benzo(a)anthracene (benz(a)anthracene):
(11)
benzo(b)fluoranthene: 4.79 x 10- 5
(12)
benzo(k)fluoranthene: 4.79 x 10-4
(13)
benzo(g,h,i,)perylene: 0.21
(14)
benzo(a)pyrene: 4.79 x 10"6
(15)
boron: 0.315
(16)
bromodichloromethane: 0.00056
(17)
bromoform (tribromomethane): 0.00443
(18)
n-butylbenzene: 0.07
(19)
sec-butylbenzene: 0.07
(20)
tert-butylbenzene: 0.07
(21)
butylbenzyl phthalate: 0.10
(22)
cadmium: 0.00175
(23)
caprolactam: 3.5
(24)
carbofuran:0.035
(25)
carbon disulfide: 0.7
(26)
carbon tetrachloride: 0.000269
(27)
chlordane: 1.0 x 10-4
(28)
chloride: 250.0
(29)
chlorobenzene: 0.05
(30)
chloroethane: 2.80
(31)
chloroform (trichloromethane): 0.07
0.0030
0.0000479
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(32)
(33)
(34)
(35)
(36)
(37)
(38)
(39)
(40)
(41)
(42)
(43)
(44)
(45)
(46)
(47)
(48)
(49)
(50)
(51)
(52)
(53)
(54)
(55)
(56)
(57)
(58)
(59)
(60)
(61)
(62)
(63)
(64)
(65)
(66)
(67)
(68)
(69)
(70)
(71)
(72)
(73)
(74)
(75)
chloromethane (methyl chloride): 2.6 x 10"3
2-chlorophenol: 0.00036
2-chlorotoluene: 0.14
chromium: 0.05
chrysene: 0.00479
cis-1,2-dichloroethene: 0.07
coliform organisms (total): 1 per 100 milliliters
color: 15 color units
copper: 1.0
cyanide (free cyanide): 0.07
2, 4-D (2,4-dichlorophenoxy acetic acid): 0.07
dibenz(a,h)anthracene: 4.7 x 10-6
1,2-dibromo-3-chloropropane: 2.5 x 10-5
dichlorodifluoromethane (Freon-12; Halon): 1.4
p,p'-dichlorodiphenyl dichloroethane (DDD): 1.4 x 104
p,p'-dichlorodiphenyltrichloroethane (DDT): 1.0 x 10�
1,1-dichloroethane: 0.07
1,2-dichloroethane (ethylene dichloride): 0.00038
1, 1 -dichloroethylene (vinylidene chloride): 0.007
1,2-dichloropropane: 0.00051
1,3-dichloropropene (cis and trans isomers): 0.00019
dieldrin: 2.2 x 10-6
di-n-butyl (or dibutyl) phthalate (DBP): 0.7
diethylphthalate (DEP): 5.0
di(2-ethylhexyl) phthalate (DEHP): 0.0025
2,4-dimethylphenol (m-xylenol): 0.14
di-n-octyl phthalate: 0.14
p-dioxane (1,4-diethylene dioxide): 0.007
dioxin: 2.2 x 10-10
diphenyl (1,1- diphenyl): 0.35
dissolved solids (total): 500
disulfoton: 2.8 x 10-4
diundecyl phthalate (Santicizer 711): 0.14
endosulfan II (beta-endosulfan): 0.0420
endrin: 0.002
endrin (total endrin: includes endrin, endrin aldehyde, and endrin ketone): 2.1 x
103
epichlorohydrin (1-chloro-2,3-epoxypropane):
ethylbenzene: 0.550
ethylene dibromide (EDB; 1,2-dibromoethane)
ethylene glycol: 14.0
fluoranthene: 0.28
fluorene: 0.28
fluoride: 2.0
foaming agents: 0.5
0.00354
4.0 x 10-7
0
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(76)
(77)
(78)
(79)
(80)
(81)
(82)
(83)
(84)
(85)
(86)
(87)
(88)
(89)
(90)
(91)
(92)
(93)
(94)
(95)
(96)
(97)
(98)
(99)
(100)
(101)
(102)
(103)
(104)
(105)
(106)
(107)
(108)
(109)
(110)
(111)
(112)
(113)
(114)
(115)
(116)
(117)
(118)
(119)
gross alpha (adjusted)particle activity (excluding radium-226 and uranium): 15
pCi/1
heptachlor: 7.8 x 10"6
heptachlor epoxide: 3.8 x 10"6
heptane: 0.42
hexachlorobenzene (perchlorobenzene): 0.00002
hexachlorocyclohexane isomers (total hexachlorocyclohexane:
alpha,beta,delta,gamma, and epsilon isomers): 1.9 x 10"5
n-hexane: 0.42
indeno(1,2,3-cd)pyrene: 4.79 x 10"5
iron: 0.3
isophorone: 0.0368
isopropylbenzene: 0.070
isopropyl ether (diisopropyl ether): 0.070
lead: 0.015
lindane: 2.0 x 10"4
manganese: 0.05
mercury: 0.00105
metadichlorobenzene (1,3-dichlorobenzene): 0.170
methanol: 3.5
methoxychlor: 0.035
methylene chloride (dichloromethane): 0.0046
methyl ethyl ketone (MEK; 2-butanone): 4.20
2-methylnaphthalene: 0.0140
3-methylphenol (m-cresol): 0.0350
4-methylphenol (p-cresol): 3.5 x 10"3
methyl tert-butyl ether (MTBE): 0.2
naphthalene: 0.021
nickel: 0.1
nitrate: (as N) 10.0
nitrite: (as N) 1.0
N-nitrosodimethylamine: 7.0 x 10"�
orthodichlorobenzene (1,2-dichlorobenzene): 0.024
oxamyl: 0.175
paradichlorobenzene (1,4-dichlorobenzene): 0.0014
pentachlorophenol: 0.00029
petroleum aliphatic carbon fraction class C5 - C8: 0.42
petroleum aliphatic carbon fraction class C9 - C 18: 4.20
petroleum aliphatic carbon fraction class C19 - C36: 42.0
petroleum aromatics carbon fraction class C9 - C22: 0.210
pH: 6.5 - 8.5
phenanthrene: 0.21
phenol: 0.30
phorate: 1.4 x 10"3
n-prop ylb enzene: 0.070
pyrene: 0.21
includes
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(120) selenium: 0.05
(121) silver: 0.0175
(122) ' simazine: 0.004
(123) styrene (ethenylbenzene): 0.1
(124) sulfate: 250.0
(125) tetrachloroethylene (perchloroethylene; PCE): 0.0007
(126) 2,3,4,6-tetrachlorophenol: 0.210
(127) toluene (methylbenzene): 1.0
(128) toxaphene: 3.1 x 10-5
(129) 2, 4, 5,-TP (Silvex): 0.05
(130) trans-1,2-dichloroethene: 0.10
(131) 1,1,1-trichloroethane (methyl chloroform): 0.2
(132) trichloroethylene (TCE): 0.0028
(133) trichlorofluoromethane: 2.1
(134) 1, 1,2-trichloro- 1,2,2-trifluoroethane (CFC-113): 210.0
(135) 1,2,3- trichloropropane: 5.0 x 10"6
(136) 1,2,4-trimethylbenzene: 0.350
(137) 1,3,5-trimethylbenzene:0.350
(138) vinyl chloride (chloroethylene): 1.5 x 10-5
(139) xylenes (o-, m-, and p-): 0.53
(140) zinc: 1.05
(h) Class GSA Standards. The standards for this class shall be the same as those for Class GA
except as follows:
(1) chloride: allowable increase not to exceed 100 percent of the natural quality
concentration.
(2) total dissolved solids: 1000 mg/l.
(i) Class GC Waters.
(1) The concentrations of substances which, at the time of classification exceed the
standards applicable to Class GA or GSA groundwaters shall not be caused to
increase, nor shall the concentrations of other substances be caused to exceed the
GA or GSA standards as a result of further disposal of contaminants to or beneath
the surface of the land within the boundary of the area classified GC.
(2) The concentrations of substances which, at the time of classification, exceed the
standards applicable to GA or GSA groundwaters shall not be caused to migrate
as a result of activities within the boundary of the GC classification, so as to
violate the groundwater or surface water quality standards in adjoining waters of a
different class.
(3) Concentrations of specific substances, which exceed the established standard at
the time of classification, shall be listed in Section .0300 of this Subchapter.
History Note: Authority G.S. 143-214.1; 143B-282(a)(2);
Eff. June 10, 1979;
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Amended Eff. November 1, 1994; October 1, 1993; September 1, 1992; August 1,
1989;
Temporary Amendment Eff. June 30, 2002;
Amended Eff. August 1, 2002;
Temporary Amendment Expired February 9, 2003;
Amended Eff. April], 2005.
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ENR - ENVIRONMENTAL MANAGEMENT 12107106
APPENDIX # 1
INTERIM MAXIMUM
ALLOWABLE
CONCENTRATIONS FOR NORTH
CAROLINA GROUNDWATERS
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ENR - ENVIRONMENTAL MANAGEMENT 12107106
APPENDIX # 1
Interim Maximum Allowable Concentrations shown in the table below are those
established under 15A NCAC 2L .0202. For more information, contact the Division of Water
Quality Planning Section at [phone] or the web site at:
htt-o://h2o.enr.state.ne.us/csu/index.htrnl.
Interim Concentrations
Substance Concentrations (mg/L) Effective Dates
Benzoic Acid
28.0
May
24,
1999
Bis(chloroethyl)ether (BCEE)
3.1 x
10-5
May
24,
1999
Dibenzofuran
0.028
May
24,
1999
Dibromochloromethane
4.1 x
10-4
May
24,
1999
Ethyl Acetate
2.60
May
24,
1999
Hexachlorobutadiene
4.4 x
10-4
May
24,
1999
2-Hexanone
0.28
May
24,
1999
1,1,2,2-Tetrachloroethane
1.7 x
10-4
May
24,
1999
1,2,4-Trichlorobenzene
0.07
May
24,
1999
Perfluorooctanoic Acid (PFOA or C8)
0.002
December
7, 2006
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