Re: [CPEO-MEF] TCE standards

[Lenny Siegel <lsiegel@cpeo.org>]

I received a couple of comments pointing out that I (in my TCE posting)
did not fully, accurately describe the process for translating a health
risk assessment to a cleanup standard in the field. The following, from
a federal employee, appears to describe the process much better.

Lenny

***

"The science of TCE toxicity aside for the moment, the health risk
assessment is just the first step.  After the HRA is approved, IRIS
(EPA's data base of toxicity values) will have to be updated, after IRIS
is updated, a rule making will be needed to change the MCL [Maximum
Contaminant Level] from 5 ug/L [micrograms per liter] to 1 ug/L.  This
is not a done deal because there are several non-health (i.e., cost and
technical practicability) factors that can be considered in setting the
new MCL.  After the MCL is proposed and adopted, it would then be a
potential ARAR [Applicable and Relevant or Appropriate Requirement] at
CERCLA sites.  After that, it would be a site-by-site analysis to see if
the new MCL is an an ARAR before the new cleanup goal would be applied.

"I think that folks a jumping the gun on this one."


-- 


Lenny Siegel
Director, Center for Public Environmental Oversight
c/o PSC, 278-A Hope St., Mountain View, CA 94041
Voice: 650/961-8918 or 650/969-1545
Fax: 650/961-8918
<lsiegel@cpeo.org>
http://www.cpeo.org

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