Wednesday, December 31, 2008

Ash Hills and Arsenic

http://www.washingtonpost.com/wp-dyn/content/article/2008/12/29/AR2008122902511.html?sub=AR
High Arsenic Levels Found in Water Near Tenn. Ash Spill


By Kristin M. Hall Associated Press Tuesday, December 30, 2008; Page A03

KINGSTON, Tenn., Dec. 29 -- Some water samples near a massive spill of coal ash in eastern Tennessee are showing high levels of arsenic, and state and federal officials Monday cautioned residents who use private wells or springs to stop drinking the water...

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BrooklynDodger(s) comment: Maybe you don't think about coal ash much, the Dodger(s) certainly didn't. What is "clean coal" anyway? The starting point of musing was that whatever stuff is in the coal that doesn't form gaseous combustion products is left behind as ash. And the coal contains whatever was in the trilobites and trees of way back when. Since living creatures contain metals, burned creatures leave behind metal oxides, which yield a high pH. Remember saponification of fats to soaps by soda ash?

But a longer-than-intended wander through google yielded some background information. The Dodger(s) invite corrections and additions to this information.

Most of us know that arsenic is known to be a human carcinogen by inhalation and by ingestion in drinking water. IARC opines "There is sufficient evidence in humans that arsenic in drinking-water causes cancers of the urinary bladder, lung and skin." The full text of this monograph can be found at http://monographs.iarc.fr/ENG/Monographs/vol84/index.php In press accounts, this classification is characterized as "has been linked to cancer" which reads much weaker than an alternative which might be "arsenic in actual drinking water people drink has caused bladder, lung and skin cancer."

The EPA MCL limit for arsenic in drinking water is 10 ppb (10 ug/L) with a goal of zero. There appear to be no EPA limits for arsenic in soil; cleanup levels are triggered by site specific considerations. Most coal ash is fly ash, there is considerable effort to finding what to do with it, although it is not deemed hazardous waste. There's even a "flyashinfo" web site. Which contains some technical papers. http://www.flyash.info/2007/105wang.pdf

According to the site, most fly ash is <>

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