Current through Register Vol. 39, No. 6, September 16, 2024
The following water quality standards shall apply to
surface waters within water supply watersheds classified as WS-II. Water
quality standards applicable to Class C waters as described in Rule .0211of
this Section shall also apply to Class WS-II waters.
(1) The best usage of waters classified as
WS-II shall be as a source of water supply for drinking, culinary, or
food-processing purposes for those users desiring maximum protection for their
water supplies where a WS-I classification is not feasible as determined by the
Commission in accordance with Rule .0212 of this Section and any best usage
specified for Class C waters.
(2)
The best usage of waters classified as WS-II shall be maintained as follows:
(a) Water quality standards in a WS-II
watershed shall meet the requirements as specified in Item (3) of this
Rule.
(b) Wastewater and stormwater
point source discharges in a WS-II watershed shall meet the requirements as
specified in Item (4) of this Rule.
(c) Nonpoint source pollution in a WS-II
watershed shall meet the requirements as specified in Item (5) of this
Rule.
(d) Following approved
treatment, as defined in Rule .0202 of this Section, the waters shall meet the
Maximum Contaminant Level concentrations considered safe for drinking,
culinary, and food-processing purposes that are specified in 40 CFR Part 141
National Primary Drinking Water Regulations and in the North Carolina Rules
Governing Public Water Supplies,
15A NCAC
18C .1500.
(e) Sources of water pollution that preclude
any of the best uses on either a short-term or long-term basis shall be deemed
to violate a water quality standard.
(f) The Class WS-II classification may be
used to protect portions of Class WS-III and WS-IV water supplies. For
reclassifications of these portions of Class WS-III and WS-IV water supplies
occurring after the July 1, 1992 statewide reclassification, a WS-II
classification that is requested by local governments shall be considered by
the Commission if all local governments having jurisdiction in the affected
areas have adopted a resolution and the appropriate ordinances as required by
G.S.
143-214.5(d) to protect the
watershed or if the Commission acts to protect a watershed when one or more
local governments has failed to adopt protective measures as required by this
Sub-Item.
(3) Water
quality standards applicable to Class WS-II Waters shall be as follows:
(a) MBAS (Methylene-Blue Active Substances):
not greater than 0.5 mg/l to protect the aesthetic qualities of water supplies
and to prevent foaming;
(b) Odor
producing substances contained in sewage or other wastes: only such amounts,
whether alone or in combination with other substances or wastes, as shall not
cause organoleptic effects in water supplies that cannot be corrected by
treatment, impair the palatability of fish, or have an adverse impact, as
defined in
15A NCAC
02H .1002, on any best usage established for
waters of this class;
(c)
Chlorinated phenolic compounds: not greater than 1.0 ug/l to protect water
supplies from taste and odor problems from chlorinated phenols;
(d) Total hardness: not greater than 100 mg/l
as calcium carbonate (CaCO3 or Ca + Mg);
(e) Solids, total dissolved: not greater than
500 mg/l;
(f) Toxic and other
deleterious substances that are non-carcinogens:
(i) Barium: 1.0 mg/l;
(ii) Chloride: 250 mg/l;
(iii) Nickel: 25 ug/l;
(iv) Nitrate nitrogen: 10.0 mg/l;
(v) 2,4-D: 70 ug/l;
(vi) 2,4,5-TP (Silvex): 10 ug/l;
and
(vii) Sulfates: 250
mg/l;
(g) Toxic and
other deleterious substances that are carcinogens:
(i) Aldrin: 0.05 ng/1;
(ii) Arsenic: 10 ug/l;
(iii) Benzene: 1.19 ug/1;
(iv) Carbon tetrachloride: 0.254
ug/l;
(v) Chlordane: 0.8
ng/1;
(vi) Chlorinated benzenes:
488 ug/l;
(vii) DDT: 0.2
ng/1;
(viii) Dieldrin: 0.05
ng/1;
(ix) Dioxin: 0.000005
ng/l;
(x) Heptachlor: 0.08
ng/1;
(xi) Hexachlorobutadiene:
0.44 ug/l;
(xii) Polynuclear
aromatic hydrocarbons (total of all PAHs): 2.8 ng/l;
(xiii) Tetrachloroethane (1,1,2,2): 0.17
ug/l;
(xiv) Tetrachloroethylene:
0.7 ug/l;
(xv) Trichloroethylene:
2.5 ug/l; and
(xvi) Vinyl Chloride:
0.025 ug/l.
(4) Wastewater and stormwater point source
discharges in a WS-II watershed shall meet the following requirements:
(a) Discharges that qualify for a General
NPDES Permit pursuant to
15A NCAC
02H .0127 shall be allowed in the entire
watershed.
(b) Discharges from
trout farms that are subject to Individual NPDES Permits shall be allowed in
the entire watershed.
(c)
Stormwater discharges that qualify for an Individual NPDES Permit pursuant to
15A NCAC
02H .0126 shall be allowed in the entire
watershed.
(d) No discharge of
sewage, industrial, or other wastes shall be allowed in the entire watershed
except for those allowed by Sub-Items (a) through (c) of this Item or Rule
.0104 of this Subchapter, and none shall be allowed that have an adverse effect
on human health or that are not treated in accordance with the permit or other
requirements established by the Division pursuant to
G.S.
143-215.1. Upon request by the Commission, a
discharger shall disclose all chemical constituents present or potentially
present in their wastes and chemicals that could be spilled or be present in
runoff from their facility that may have an adverse impact on downstream water
quality. These facilities may be required to have spill and treatment failure
control plans as well as perform special monitoring for toxic
substances.
(e) New domestic and
industrial discharges of treated wastewater that are subject to Individual
NPDES Permits shall not be allowed in the entire watershed.
(f) No new landfills shall be allowed in the
Critical Area, and no NPDES permits shall be issued for landfills that
discharge treated leachate in the remainder of the watershed.
(g) No new permitted sites for land
application of residuals or petroleum contaminated soils shall be allowed in
the Critical Area.
(5)
Nonpoint source pollution in a WS-II watershed shall meet the following
requirements:
(a) Nonpoint source pollution
shall not have an adverse impact on waters for use as a water supply or any
other designated use.
(b) Class
WS-II waters shall be protected as water supplies that are located in
watersheds that meet average watershed development density levels specified for
Class WS-II waters in Rule .0624 of this Subchapter.
Authority
G.S.
143-214.1;
143-215.3(a)(1);
Eff. May 10, 1979;
Amended Eff. January 1, 2015; May 1, 2007; April
1, 2003; January 1, 1996; October 1, 1995;
Readopted Eff. November
1, 2019.