North Carolina Administrative Code › Title 15A - Environmental Quality › Chapter 02 - Environmental Management › Subchapter B - SURFACE WATER AND WETLAND STANDARDS › Section .0200 - CLASSIFICATIONS AND WATER QUALITY STANDARDS APPLICABLE TO SURFACE WATERS AND WETLANDS OF NORTH CAROLINA › Section 02B .0220 - TIDAL SALT WATER QUALITY STANDARDS FOR CLASS SC WATERS

Current through Register Vol. 39, No. 2, July 15, 2024
In addition to the standards set forth in Rule .0208 of
					 this Section, the following water quality standards shall apply to all Class SC
					 waters. Additional standards applicable to other tidal salt water
					 classifications are specified in Rules .0221 and .0222 of this Section.
(1) The best usage of waters classified as SC
				  shall be aquatic life propagation, survival, and maintenance of biological
				  integrity (including fishing, fish, and Primary Nursery Areas (PNAs));
				  wildlife; secondary contact recreation as defined in Rule .0202 in this
				  Section; and any usage except primary contact recreation or shellfishing for
				  market purposes. All saltwaters shall be classified to protect these uses at a
				  minimum.
(2) The best usage of
				  waters classified as SC shall be maintained as specified in this Rule. Any
				  source of water pollution that precludes any of these uses on either a
				  short-term or a long-term basis shall be deemed to violate a water quality
				  standard;
(3) Chlorophyll a
				  (corrected): not greater than 40 ug/l in sounds, estuaries, and other waters
				  subject to growths of macroscopic or microscopic vegetation. The Commission or
				  its designee may prohibit or limit any discharge of waste into surface waters
				  if the Director determines that the surface waters experience or the discharge
				  would result in growths of microscopic or macroscopic vegetation such that the
				  standards established pursuant to this Rule would be violated or the intended
				  best usage of the waters would be impaired;
(4) Cyanide: 1 ug/l;
(5) Dissolved oxygen: not less than 5.0 mg/l,
				  except that swamp waters, poorly flushed tidally influenced streams or
				  embayments, or estuarine bottom waters may have lower values if caused by
				  natural conditions;
(6)
				  Enterococcus, including Enterococcus faecalis, Enterococcus faecium,
				  Enterococcus avium and Enterococcus gallinarium: not exceed a geometric mean of
				  35 enterococci per 100 ml based upon a minimum of five samples taken over a
				  30-day period. For the purposes of beach monitoring and notification, "Coastal
				  Recreational Waters Monitoring, Evaluation and Notification" regulations
				  (15A
				  NCAC 18A .3400), available free of charge at:
http://www.ncoah.com/
, are
				  incorporated by reference including subsequent amendments and
				  editions;
(7) Floating solids,
				  settleable solids, or sludge deposits: only such amounts attributable to
				  sewage, industrial wastes, or other wastes as shall not make the waters unsafe
				  or unsuitable for aquatic life and wildlife, or impair the waters for any
				  designated uses;
(8) Gases, total
				  dissolved: not greater than 110 percent of saturation;
(9) Metals:
(a) With the exception of mercury and
				  selenium, acute and chronic tidal salt water quality standards for metals shall
				  be based upon measurement of the dissolved fraction of the metals. Mercury and
				  selenium shall be based upon measurement of the total recoverable
				  metal;
(b) With the exception of
				  mercury and selenium, acute and chronic tidal saltwater quality aquatic life
				  standards for metals listed in this Sub-Item shall apply as a function of the
				  pollutant's water effect ratio (WER). The WER shall be assigned a value equal
				  to one unless any person demonstrates to the Division in a permit proceeding
				  that another value is developed in accordance with the "Water Quality Standards
				  Handbook: Second Edition" published by the US Environmental Protection Agency
				  (EPA-823-B-12-002). Alternative site-specific standards may also be developed
				  when any person submits values that demonstrate to the Commission that they
				  were derived in accordance with the "Water Quality Standards Handbook: Second
				  Edition, Recalculation Procedure or the Resident Species Procedure."
(c) Acute and chronic tidal salt water
				  quality metals standards shall be as follows:
(i) Arsenic, acute: WER. 69 ug/l;
(ii) Arsenic, chronic: WER. 36
				  ug/l;
(iii) Cadmium, acute: WER. 33
				  ug/l;
(iv) Cadmium, chronic: WER.
				  7.9 ug/l;
(v) Chromium VI, acute:
				  WER. 1100 ug/l;
(vi) Chromium VI,
				  chronic: WER. 50 ug/l;
(vii)
				  Copper, acute: WER. 4.8 ug/l;
(viii) Copper, chronic: WER. 3.1
				  ug/l;
(ix) Lead, acute: WER. 210
				  ug/l;
(x) Lead, chronic: WER. 8.1
				  ug/l;
(xi) Mercury, total
				  recoverable, chronic: 0.025 ug/l;
(xii) Nickel, acute: WER. 74 ug/l;
(xiii) Nickel, chronic: WER. 8.2
				  ug/l;
(xiv) Selenium, total
				  recoverable, chronic: 71 ug/l;
(xv)
				  Silver, acute: WER. 1.9 ug/l;
(xvi)
				  Silver, chronic: WER. 0.1 ug/l;
(xvii) Zinc, acute: WER. 90 ug/l;
				  and
(xviii) Zinc, chronic: WER. 81
				  ug/l;
(d) Compliance
				  with acute instream metals standards shall only be evaluated using an average
				  of two or more samples collected within one hour. Compliance with chronic
				  instream metals standards shall only be evaluated using averages of a minimum
				  of four samples taken on consecutive days, or as a 96-hour average;