15A NCAC 02B .0220. TIDAL SALT WATER QUALITY STANDARDS FOR CLASS SC WATERS

General.  The water quality standards for all tidal salt waters are the basic standards applicable to Class SC waters.  Additional and more stringent standards applicable to other specific tidal salt water classifications are specified in Rules .0221 and .0222 of this Section.

(1)           Best Usage of Waters:  any usage except primary recreation or shellfishing for market purposes; usages include aquatic life propagation and maintenance of biological integrity (including fishing, fish and functioning PNAs), wildlife, and secondary recreation;

(2)           Conditions Related to Best Usage:  the waters shall be suitable for aquatic life propagation and maintenance of biological integrity, wildlife, and secondary recreation.   Any source of water pollution which precludes any of these uses, including their functioning as PNAs, on either a short‑term or a long‑term basis shall be considered to be violating a water quality standard;

(3)           Quality standards applicable to all tidal salt waters:

(a)           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, in the opinion of the Director, 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;

(b)           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;

(c)           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;

(d)           Gases, total dissolved:  not greater than 110 percent of saturation;

(e)           Enterococcus, including Enterococcus faecalis, Enterococcus faecium, Enterococcus avium and Enterococcus gallinarium: not to exceed a geometric mean of 35 enterococci per 100 ml based upon a minimum of five samples within any consecutive 30 days.  In accordance with 33 U.S.C. 1313 (Federal Water Pollution Control Act) for purposes of beach monitoring and notification, "Coastal Recreational Waters Monitoring, Evaluation and Notification" regulations (15A NCAC 18A .3400) are hereby incorporated by reference including any subsequent amendments;

(f)            Oils, deleterious substances, colored or other wastes:  only such amounts as shall not render the waters injurious to public health, secondary recreation or  aquatic life and wildlife or adversely affect the palatability of fish, aesthetic quality or impair the waters for any designated uses.  For the purpose of implementing this Rule, oils, deleterious substances, colored or other wastes shall include but not be limited to substances that cause a film or sheen upon or discoloration of the surface of the water or adjoining shorelines pursuant to 40 CFR 110.3;

(g)           pH:  shall be normal for the waters in the area, which generally shall range between 6.8 and 8.5 except that swamp waters may have a pH as low as 4.3 if it is the result of natural conditions;

(h)           Phenolic compounds:  only such levels as shall not result in fish‑flesh tainting or impairment of other best usage;

(i)            Radioactive substances:

(i)            Combined radium‑226 and radium‑228:  The maximum average annual activity level (based on at least four samples, collected quarterly) for combined radium‑226, and radium‑228 shall not exceed five picoCuries per liter;

(ii)           Alpha Emitters.  The average annual gross alpha particle activity (including radium‑226, but excluding radon and uranium) shall not exceed 15 picoCuries per liter;

(iii)          Beta Emitters.  The maximum average annual activity level (based on at least four samples, collected quarterly) for strontium‑90 shall not exceed eight picoCuries per liter; nor shall the average annual gross beta particle activity (excluding potassium‑40 and other naturally occurring radio‑nuclides) exceed 50 picoCuries per liter; nor shall the maximum average annual activity level for tritium exceed 20,000 picoCuries per liter;

(j)            Salinity:  changes in salinity due to hydrological modifications shall not result in removal of the functions of a PNA.  Projects that are determined by the Director to result in modifications of salinity such that functions of a PNA are impaired will be required to employ water management practices to mitigate salinity impacts;

(k)           Temperature:  shall not be increased above the natural water temperature by more than 0.8 degrees C (1.44 degrees F) during the months of June, July, and August nor more than 2.2 degrees C (3.96 degrees F) during other months and in no cases to exceed 32 degrees C (89.6 degrees F) due to the discharge of heated liquids;

(l)            Turbidity:  the turbidity in the receiving water shall not exceed 25 NTU; if turbidity exceeds this level due to natural background conditions, the existing turbidity level shall not be increased.  Compliance with this turbidity standard can be met when land management activities employ Best Management Practices (BMPs) [as defined by Rule .0202 of this Section] recommended by the Designated Nonpoint Source Agency (as defined by Rule .0202 of this Section).  BMPs must be in full compliance with all specifications governing the proper design, installation, operation and maintenance of such BMPs;

(m)          Toxic substances:  numerical water quality standards (maximum permissible levels) to protect aquatic life applicable to all tidal saltwaters:

(i)            Arsenic, total recoverable:  50 ug/l;

(ii)           Cadmium:  5.0 ug/l; attainment of these water quality standards in surface waters shall be based on measurement of total recoverable metals concentrations unless appropriate studies have been conducted to translate total recoverable metals to a toxic form.  Studies used to determine the toxic form or translators must be designed according to the "Water Quality Standards Handbook Second Edition" published by the Environmental Protection Agency (EPA 823-B-94-005a) or "The Metals Translator: Guidance For Calculating a Total Recoverable Permit Limit From a Dissolved Criterion" published by the Environmental Protection Agency (EPA 823-B-96-007) which are hereby incorporated by reference including any subsequent amendments.  The Director shall consider conformance to EPA guidance as well as the presence of environmental conditions that limit the applicability of translators in approving the use of metal translators;

(iii)          Chromium, total:  20 ug/l;

(iv)          Cyanide:  1.0 ug/l;

(v)           Mercury:  0.025 ug/l;

(vi)          Lead, total recoverable:  25 ug/l; collection of data on sources, transport and fate of lead shall be required as part of the toxicity reduction evaluation for dischargers that are out of compliance with whole effluent toxicity testing requirements and the concentration of lead in the effluent is concomitantly determined to exceed an instream level of 3.1 ug/l from the discharge;

(vii)         Nickel:  8.3 ug/l; attainment of these water quality standards in surface waters shall be based on measurement of total recoverable metals concentrations unless appropriate studies have been conducted to translate total recoverable metals to a toxic form.  Studies used to determine the toxic form or translators must be designed according to the "Water Quality Standards Handbook Second Edition" published by the Environmental Protection Agency (EPA 823-B-94-005a) or "The Metals Translator: Guidance For Calculating a Total Recoverable Permit Limit From a Dissolved Criterion" published by the Environmental Protection Agency (EPA 823-B-96-007) which are hereby incorporated by reference including any subsequent amendments.  The Director shall consider conformance to EPA guidance as well as the presence of environmental conditions that limit the applicability of translators in approving the use of metal translators;

(viii)        Pesticides:

(A)          Aldrin:  0.003 ug/l;

(B)          Chlordane:  0.004 ug/l;

(C)          DDT:  0.001 ug/l;

(D)          Demeton:  0.1 ug/l;

(E)           Dieldrin:  0.002 ug/l;

(F)           Endosulfan:  0.009 ug/l;

(G)          Endrin:  0.002 ug/l;

(H)          Guthion:  0.01 ug/l;

(I)            Heptachlor:  0.004 ug/l;

(J)            Lindane:  0.004 ug/l;

(K)          Methoxychlor:  0.03 ug/l;

(L)           Mirex:  0.001 ug/l;

(M)         Parathion:  0.178 ug/l;

(N)          Toxaphene:  0.0002 ug/l;

(ix)          Polychlorinated biphenyls:  (total of all PCBs and congeners identified)  0.001 ug/l;

(x)           Selenium:  71 ug/l;

(xi)          Trialkyltin compounds:  0.007 ug/l expressed as tributyltin.

(4)           Action Levels for Toxic Substances:

(a)           Copper:  3 ug/l;

(b)           Silver:  0.1 ug/l;

(c)           Zinc:  86 ug/l;

If the Action Levels for any of the substances listed in this Subparagraph (which are generally not bioaccumulative and have variable toxicity to aquatic life because of chemical form, solubility, stream characteristics or associated waste characteristics) are determined by the waste load allocation to be exceeded in a receiving water by a discharge under the specified low flow criterion for toxic substances (Rule .0206 in this Section), the discharger shall be required to monitor the chemical or biological effects of the discharge; efforts shall be made by all dischargers to reduce or eliminate these substances from their effluents.  Those substances for which Action Levels are listed in this Subparagraph may be limited as appropriate in the NPDES permit if sufficient information (to be determined for metals by measurements of that portion of the dissolved instream concentration of the Action Level parameter attributable to a specific NPDES permitted discharge) exists to indicate that any of those substances may be a causative factor resulting in toxicity of the effluent.  NPDES permit limits may be based on translation of the toxic form to total recoverable metals.  Studies used to determine the toxic form or translators must be designed according to: "Water Quality Standards Handbook Second Edition" published by the Environmental Protection Agency (EPA 823-B-94-005a) or "The Metals Translator: Guidance For Calculating a Total Recoverable Permit Limit From a Dissolved Criterion" published by the Environmental Protection Agency (EPA 823-B-96-007) which are hereby incorporated by reference including any subsequent amendments.  The Director shall consider conformance to EPA guidance as well as the presence of environmental conditions that limit the applicability of translators in approving the use of metal translators.

 

History Note:        Authority G.S. 143‑214.1; 143‑215.3(a)(1);

Eff. October 1, 1995;

Amended Eff. May 1, 2007; August 1, 2000.