[CPEO-MEF] GAO issues perchlorate overview

[Lenny Siegel <lsiegel@cpeo.org>]

The Government Accountability Office (GAO) has just released an overview 
of the national perchlorate contamination problem. I have pasted the 
official "Highlights" below. Please note that Appendix II catalogs 
perchlorate finds at nearly 400 sites in the U.S., as of January, 2005.


PERCHLORATE: A System to Track Sampling and Cleanup Results Is Needed
May 20, 2005
GAO-05-462

To download the full report, click on
http://www.gao.gov/cgi-bin/getrpt?GAO-05-462

*********

Perchlorate contamination has been found in water and soil at almost 400 
sites in the United States where concentration levels ranged from a 
minimum reporting level of 4 parts per billion to millions of parts per 
billion. More than one-half of all sites were in California and Texas, 
and sites in Arkansas, California, Texas, Nevada, and Utah had some of 
the highest concentration levels. Yet, most sites had lower levels of 
contamination; roughly two-thirds of sites had concentration levels at 
or below the Environmental Protection Agency's (EPA) provisional cleanup 
standard of 18 parts per billion. Federal and state agencies are not 
required to routinely report perchlorate findings to EPA, and EPA does 
not centrally track or monitor perchlorate detections or the status of 
cleanup. As a result, a greater number of contaminated sites than we 
reported may already exist.

Although there is no specific federal requirement to clean up 
perchlorate, EPA and state agencies have used broad authorities under 
various environmental laws and regulations, as well as state laws and 
action levels, to sample and clean up and/or require the sampling and 
cleanup of perchlorate by responsible parties. Further, under certain 
federal and state environmental laws, private industry may be required 
to sample for contaminants, such as perchlorate. According to EPA and 
state officials, private industry and public water suppliers have 
generally complied with regulations requiring sampling and agency 
requests to sample. The Department of Defense (DOD) has sampled and 
cleaned up perchlorate in some locations when required by laws and 
regulations, but the department has been reluctant to sample on or near 
active installations under other circumstances. Except where there is a 
specific legal requirement, DOD's perchlorate sampling policy requires 
the services to sample only under certain conditions. Cleanup is planned 
or under way at 51 of the almost 400 perchlorate-contaminated sites 
identified to date.

Since 1998, EPA and DOD have sponsored a number of perchlorate health 
risk studies using varying study methodologies. We reviewed 90 of these 
studies that generally examined whether and how perchlorate affected the 
thyroid. About one-quarter concluded that perchlorate had an adverse 
effect. In January 2005, NAS reported on the potential health effects of 
perchlorate and concluded that a total exposure level from all sources, 
higher than that initially recommended by EPA (a dose equivalent to 1 
part per billion in drinking water, assuming that all exposure came from 
drinking water) may not adversely affect a healthy adult. On the basis 
of NAS' report, EPA revised its reference dose to a level that is 
equivalent to 24.5 parts per billion in drinking water (if it is assumed 
that all exposure comes only from drinking water). The reference dose is 
not a drinking water standard; it is a scientific estimate of the total 
daily exposure level from all sources that is not expected to cause 
adverse effects in humans, including the most sensitive populations.


--
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
http://www.cpeo.org


_______________________________________________
Military mailing list
Military@list.cpeo.org
http://www.cpeo.org/mailman/listinfo/military