SPECIAL METALS EXTRACTIONS
TTLCTTLC stands for "Total Threshold Limit Concentration." This is how metals results are normally expressed for solid samples. If you do not specify a special extraction procedure on your chain of custody your metals will be reported as TTLC values.
CAM / STLCSTLC stand for "Soluble Threshold Limit Concentration." This extraction is used to determine whether certain leachable compounds are present in large enough amounts in a given material that the material need to be dealt with as hazardous waste. The extraction procedure mimics what will happen to a given material as it is exposed to normal climatic conditions in a landfill over time. When this extraction is used solid matrices will be reported in liquid units.
TCLPTCLP stands for "Toxicity Characteristic Leaching Procedure." This extraction is one of four characteristics used to identify hazardous waste; the other three are Ignitabilty, Corrosivity and Reactivity. The TCLP extraction is designed to simulate the climatic leaching action expected to occur in landfills. It identifies and quantifies 8 metals and 25 organic compounds (pesticides, herbicides, etc.) with the potential to leach into ground water. When this extraction is used solid matrices will be reported in liquid units.
When to do a STLC extraction.The limits for STLC and TTLC metals are listed below along with the range of TTLC concentrations for which a STLC extraction must be done.
| SUBSTANCE | STLC (mg/L) | RANGE OF TTLC VALUES FOR WHICH AN STLC MUST BE DONE | TTLC (mg/kg) | | Antimony | 15 | 150 mg/kg or greater | 500 | | Arsenic | 5.0 | 50 mg/kg or greater | 500 | | Barium | 100 | 1000 mg/kg or greater | 10,000 | | Beryllium | 0.75 | 7.5 mg/kg or greater | 75 | | Cadmium | 1.0 | 10 mg/kg or greater | 100 |
Chromium 6 | 5.0 | 50 mg/kg or greater | 500 | | Chromium | 5.0 | 50 mg/kg or greater | 2,500 |
Cobalt | 80 | 800 mg/kg or greater | 8,000 | | Copper | 25 | 250 mg/kg or greater | 2,500 | | Lead | 5.0 | 50 mg/kg or greater | 1,000 | | Mercury | 0.2 | 2 mg/kg or greater | 20 | | Molybdenum | 350 | 3,500 mg/kg or greater | 3,500 | | Nickel | 20 | 200 mg/kg or greater | 2,000 | | Selenium | 1.0 | 10 mg/kg or greater | 100 | | Silver | 5.0 | 50 mg/kg orgreater | 500 | | Thallium | 7.0 | 70 mg/kg or greater | 700 | | Vanadium | 24 | 240 mg/kg or greater | 2,400 | | Zinc | 250 | 2,500 mg/kg or greater | 5,000 |
If you have a solid sample analyzed for metals (TTLC) you must do an STLC for those metals that are 10 times or greater than the STLC limit. For example – The TTLC limit for antimony is 500 mg/kg and the STLC limit is 15 mg/L. If your TTLC result is 150 mg/kg or higher they you must do an STLC for antimony.
|
Top of Page