Water Quality Problem: Metals

The states of Alaska, California, New Jersey, and Washington, and Puerto Rico, are subject to the revised metals criteria below.
Designated Use Metal Limit (ug/l)
Estuarine/
     Coastal
     Aquatic Life		    
  As 50.0#
  Ag 0.10 #
  Be 117 ng/l #
  Cd 5.00 #
    8.00 *
  Cr 20.0 #
  Cu 2.90
  Hg 0.025 *
  Ni 7.10 +
  Pb 5.80 *
  Se 71.0 #
  Zn 76.6 * 
               
One-hour average concentration

       * Four-day average concentration

       + Twenty-four hour average concentration

       (Adapted from EPA, 1986; Georgia Code, 1993; Florida Code, 1993;
      Washington Code, 1992; Texas Code, 1991; North Carolina,
      1991).

       # From North Carolina Code, 1994; note Beryllium limit is for
      human health
Saltwater Dissolved Metals Criteria
 
Metal Total Recoverable Metals Critera Dissolved Metals Criteria
in ug/l CMC CCC CMC CCC
Arsenic 68.55 36.05 69 36
Cadmium 42.54 9.345 42 9.3
Chromium (VI) 1079 49.86 1100 50
Copper 2.916 2.916 2.4 2.4
Lead 217.16 8.468 210 8.1
Mercury 2.062 .0250 1.8 N/A
Nickel 74.6 8.293 74 8.2
Selenium 293.8 70.69 290 71
Silver 2.3 N/A 1.9 N/A
Zinc 95.1 86.14 90 81

- Total recoverable metals criteria is from EPA National Ambient Water Quality Criteria Documents.
- Criteria Maximum Concentration (CMC) is the highest concentration of a pollutant to which aquatic life can be exposed for a short period of time (1 hour average) (acute);
- Criteria Continuous Concentration (CCC) is the highest concentration of a pollutant to which aquatic life can be exposed for an extended period of time (4 days) without deleterious effects (chronic).
- A more conservative approach to aquatic life protection may be preferred; in such cases the total recoverable metals criteria may be used.

If your concentrations are larger than these, there is a water quality problem;
Click here to go to the problem page.



? Information on metals.