Metals_Standards_Table_02092015_final_1

Disclaimer: This table is intended to provide summary information only. It does not substitute for any written regulation, nor is it a regulation itself.
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North Carolina Surface Water Pollutant Standards
for Metals
Effective 01/01/2015
Pollutant
Freshwater Aquatic Life Saltwater Aquatic Life Water Supply1
(µg/L)
Human
Health2
(µg/L)
Carcinogen3 Acute
(µg/L)
Chronic
(µg/L)
Trout Waters
(µg/L)
Acute
(µg/L) Chronic
(µg/L)
Arsenic
(CAS # 7440-38-2) 340 (d) 150 (d) - 69 (d) 36 (d) 10 (t) 10 (t) Yes
Barium
(CAS # 44-39-3) - - - - - 1000 (t) - No
Beryllium
(CAS # 7440-41-7) 65 (d) 6.5 (d) - - - - - No
Cadmium
(CAS # 7440-43-9) 0.82 (d)(h) 0.15 (d)(h) 0.51 (d)(h) 40 (d) 8.8 (d) - - No
Chromium III 180 (d)(h) 24 (d)(h) - - - - - No
Chromium VI 16 (d) 11 (d) - 1100 (d) 50 (d) - - No
Copper
(CAS # 7440-50-8)
3.6 (d)(h) or
Copper 2007 Revision
(EPA-822-R-07-001)
2.7 (d)(h) or
Copper 2007 Revision
(EPA-822-R-07-001)
- 4.8 (d) 3.1 (d) - - No
Lead
(CAS # 7439-92-1) 14 (d)(h) 0.54 (d)(h) - 210 (d) 8.1 (d) - - No
Mercury
(CAS # 7439-97-6) - 0.012 (t) - - 0.025 (t) - - No
Nickel
(CAS # 7440-02-0) 140 (d)(h) 16 (d)(h) - 74 (d) 8.2 (d) 25 (t) - No
Selenium
(CAS # 7782-49-2) - 5 (t) - - 71 (t) - - No
Silver
(CAS # 7440-22-4) 0.30 (d)(h) 0.06 (d) - 1.9 (d) 0.1 (d) - - No
Zinc
(CAS # 7440-66-6) 36 (d)(h) 36 (d)(h) - 90 (d) 81 (d) - - No
Footnotes, Codes and Additional Information with Reference to Classifications & Standards
(d) = dissolved metal standard. See 15A NCAC 02B .0211 for more information.
(h) = hardness-dependent dissolved metal standard. All hardness-dependent dissolved metal standards in this table assume ≤ 25 mg/L in-stream hardness. See below for
hardness-dependent dissolved metal guidelines and equations. See 15A NCAC 02B .0211 for more information.
(t) = based upon measurement of total recoverable metal. See 15A NCAC 02B .0211 for more information. **Continued on next page**

Disclaimer: This table is intended to provide summary information only. It does not substitute for any written regulation, nor is it a regulation itself.
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Footnotes, Codes and Additional Information with Reference to Classifications & Standards
The standards in this table are adopted per section 15A NCAC 02B of the North Carolina Administrative Code.
To determine the appropriate standard, use the most stringent of all applicable columns as described below.
• For Class C waters, use the most stringent of Freshwater and Human Health.
• For Class SC waters, use the most stringent of Saltwater and Human Health.
• For Water Supply waters, use the most stringent of Freshwater, Water Supply, and Human Health.
• For Trout Waters, use the most stringent of Freshwater, Human Health, and Trout. If Trout Waters are located within a Water Supply, use the most stringent of
Freshwater, Human Health, Water Supply, and Trout.
1. Water Supply standards are applicable to all Water Supply
Classifications and are based on consumption of fish and
water. See 15A NCAC 02B .0208 for equation.
2. Human Health standards are based on the consumption of
fish only unless dermal contact studies are available. See 15A
NCAC 02B .0208 for equations.
3. Carcinogens are listed in 15A NCAC 02B .0208.
Hardness-Dependent Dissolved Metal Standard Guidelines and Equations

Use the guidelines and equations below for determining hardness-dependent dissolved metal standards:

If in-stream hardness ≤25 mg/L, calculate at 25 mg/L hardness
If in-stream hardness >25, but <400 mg/L, calculate at actual stream hardness
If in-stream hardness >400, calculate at 400 mg/L hardness
Metal Equations for Hardness-Dependent Metals (ug/L)
(The Water Effects Ratio (WER) in the equations below = 1)
Standard @ 25 mg/L in-
stream hardness (ug/L)
Cadmium, acute WER*[{1.136672-[ln hardness](0.041838)}*e^{0.9151[ln hardness]-3.1485}] 0.82
Cadmium, chronic WER*[{1.101672-[ln hardness](0.041838)}*e^{0.7998[ln hardness]-4.4451}] 0.15
Cadmium, acute, trout waters WER*[{1.136672-[ln hardness](0.041838)}*e^{0.9151[ln hardness]- 3.6236}] 0.51
Chromium III, acute WER*[0.316*e^{0.8190[ln hardness]+3.7256}] 180
Chromium III, chronic WER*[0.860*e^{0.8190[ln hardness]+0.6848}] 24
Copper, acute WER*[0.960*e^{0.9422[ln hardness]-1.700}] 3.6
Copper, chronic WER*[0.960*e^{0.8545[ln hardness]-1.702}] 2.7
Lead, acute WER*[{1.46203-[ln hardness](0.145712)}*e^{1.273[ln hardness]-1.460}] 14
Lead, chronic WER*[{1.46203-[ln hardness](0.145712)}*e^{1.273[ln hardness]-4.705}] 0.54
Nickel, acute WER*[0.998*e^{0.8460[ln hardness]+2.255}] 140
Nickel, chronic WER*[0.997*e^{0.8460[ln hardness]+0.0584}] 16
Silver, acute WER*[0.85*e^{1.72[ln hardness]-6.59}] 0.30
Zinc, acute WER*[0.978*e^{0.8473[ln hardness]+0.884}] 36
Zinc, chronic WER*[0.986*e^{0.8473[ln hardness]+0.884}] 36