Test Method 1311: Toxicity Characteristic Leaching Procedure (TCLP) in “Test Methods for Evaluating Solid Waste, Physical/Chemical Methods,” EPA Publication SW–846 and EPA, 40 CFR, Part 261 is widely used, not only in the US.
The associated parameter list is the so-called D-list aka D-codes which includes 43 single parameters but next to many others, what you commonly can re-calculate from the US Drinking Water Ordinance "CYANIDES" are missing.
Any idea, why such a vital parameter was not listed?
Thank you and Glück Auf!
Dr. Rüdiger B. Richter
Weak acid dissociable cyanide criteria limits are available in some regulations and standards as available in the Guidance Document, Department of Environment Pollution Prevention Division, Guidance Document, GOVERNMENT OF NEWFOUNDLAND AND LABRADOR.
But for total cyanide, may be criteria limits are not readily available. Additional research may be required.
Dear Dr. Rama,
thank you for your answer. - I was thinking, that thousands of US Americans on this platform are keen to explain the rest of the world their cryptic guide lines.
I like your answer.
Regards
Cyanide was listed initially under chapter 7 "Reactive Cyanides Released From Wastes" however the USEPA rescinded the method in 1998- here is the language (see attachment for full text).
"After this careful consideration, it is our conclusion that there were critical errors made in developing the guidance, that your concerns regarding the reliability of the guidance are well founded, and that the guidance should be withdrawn."
Until revised guidance is developed, we reiterate the RCRA regulatory language.That is, 40 CFR 261.23(a)(5) specifies that human health and the environment must not be endangered by evolved toxic gases when these wastes are exposed to pH conditions between 2 and 12.5. Any waste causing a hazard, when in the pH range of 2-12.5, would certainly be considered a characteristic hazardous waste. We understand that withdrawal of the guidance today means that waste generators who have relied on this guidance in the past will, in the near term, have somewhat greater uncertainty about determining the regulatory status of their cyanide- and sulfide-bearing wastes. However, the Agency believes that generators of sulfide- and cyanide-bearing wastes can recognize the acute toxicity of sulfides and cyanides without relying on the test in the guidance. Where wastes with high concentrations of soluble sulfides and cyanides are being managed, generators have relied on their knowledge of the waste to classify them as D003. The Agency expects that generators should continue to classify their high concentration sulfide- and cyanide-bearing wastes as hazardous based on the narrative standard.
Hope this helps you understand why it was rescinded - The language is still there for regulatory purposes.
Dear Peter,
Sorry English is not my mother tongue. - I have understood that the Cyanide and Sulfide Reactivity Guidance had been withdrawn already in 1998!? - Memo attached.
Do you refer to this withdrawn guideline?
Kind regards
Rüdiger
Yes, it was EPA National Enforcement Investigations Center (NEIC) that raised concern over the analytical method for cyanide reactivity. I had attached the guidance, however it was not posted in my response by RG.
Remember that TCLP is leaching characteristic, and is a parameter used (mostly) by landfill operators to determine whether wastes can be safely disposed of in their landfills. This was developed due to many former dumps (landfills) ending up being highly toxic due to hazardous waste disposal prior to regulations. Most landfills in USA used prior to 1970 have ended up as superfund sites.
More info in the link below:
http://www.epa.gov/wastes/hazard/tsd/ldr/ldr-sum.pdf
Dear Peter,
Thank you for your afford and your kind explanation.
Kind regards
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