Responsible Parties' view of TCE standard

[Lenny Siegel <lsiegel@cpeo.org>]

[I've recently sent out a couple of items that I've written calling for U.S.
EPA to continue using its stringent provisional TCE screening levels.
>From the public record of comments on the Five-Year Review of Mountain
View's "MEW Study Area" Superfund Remedy, I am including below an alternate
view, that of two of the largest responsible parties at that site. I have only
included that portion of their comments relevant to the TCE standard.  Anyone
who wants the entire, formatted comments, complete with a technical "Analysis
of Carcinogenicity Data" can request the PDF file from me. - Lenny]

Locus Technologies
299 Fairchild Drive
Mountain View, California 94043
http://www.locustec.com

14 July 2004

Ms. Alana Lee
Project Manager
SFD-7-3
EPA Region IX
75 Hawthorne Street
San Francisco, CA 94102
RE: Comments on EPA's draft First Five-Year Review Report for
Middlefield-Ellis-Whisman (MEW) Superfund Study Area, Mountain View, CA
Locus Project No. 23007-04-2500

Dear Ms. Lee:

This letter provides comments on the EPA's draft First Five-Year Review
Report for Middlefield- Ellis-Whisman (MEW) Superfund Study Area in
Mountain View, California (Report). Locus Technologies submits these
comments on behalf of Fairchild Semiconductor Corporation and Raytheon
Company (collectively, the Companies).
General Comments:

1. The Companies' single most significant concern with EPA's draft Report is
its continued reference to the 2001 Draft TCE Health Risk Assessment
[Trichloroethylene Health Risk Assessment: Synthesis and Characterization,
August 2001, U.S. EPA Office of Research and Development.] ("Draft TCE Risk
Assessment") as a basis for assessing TCE toxicity. As the MEW Companies have
commented previously, use of the Draft TCE Risk Assessment is scientifically
inappropriate and contrary to EPA policy and law.

Beginning with the notice that announced the availability of the Draft TCE
Health Risk Assessment in 2001, the document's conclusions were clearly
identified as preliminary and not to be used to establish policy or as the
basis of Agency decision- making. That notice states specifically: "This report
is a draft for review purposes only and does not constitute Agency policy." 66
Fed. Reg. at 48257, September 19, 2001. The cover of the Draft TCE Health Risk
Assessment report itself, which is labeled "external review draft," prominently
displays the following notice:

"THIS DOCUMENT IS A PRELIMINARY DRAFT. It has not been formally released by
the U.S. Environmental Protection Agency and should not at this stage be
construed to represent Agency policy. It is being circulated for comment on
its technical merit and policy implications."

The same inscription appears on the title page, and every page of the document
bears the prohibition: "DRAFT - DO NOT CITE OR QUOTE." The opening paragraph of
the document's introduction states again: "This document is a draft for review
purposes only and does not constitute Agency policy."

Following its release for public comment, the Draft TCE Risk Assessment was the
subject of voluminous substantive comments. As a result, EPA sought peer review
through its own Science Advisory Board ("SAB"). The SAB's review of the
document in 2002 identified a number of significant deficiencies, noting that
"the new areas explored involve considerable uncertainty" and expressing the
"need to strengthen the rigor of the discussions in the revised assessment so
that the basis for all derived values is transparent and clearly supported by
the available data. The Board notes that public comments have raised valid
concerns that the Agency should carefully address." [Review of Draft
Trichloroethylene Health Risk Assessment: Synthesis and Characterization: An
EPA Science Advisory Board Report, p.1, December 2, 2002.] Given the
uncertainties, EPA has now requested a further peer review of TCE's toxicity by
the National Academy of Sciences. That review is expected to begin shortly and
to take 18 months to 2 years to complete.

Despite the deficiencies identified in the Draft TCE Risk Assessment, EPA
Region 9 used it to calculate new Preliminary Remediation Goal screening levels
and has disseminated those PRGs publicly as valid evaluation criteria. The most
recent dissemination is contained in Section 6.2.2 of the Report.

This is contrary not only to the expressions of EPA policy against the use of
draft reports noted above, but also is contrary to the most recent applicable
formal EPA policy on the topic expressed in OSWER Directive 9285.7-53. That
Directive states: "In general, draft toxicity assessments are not appropriate
for use until they have been through peer review, the peer review comments have
been addressed in a revised draft, and the revised draft is publicly
available." OSWER Directive 9285.7-53, p.3, December 5, 2003. EPA Region 9's
continuing premature use of the Draft TCE Risk Assessment violates this policy.
It is also contrary to the Administrative Procedure Act, the Data Quality Act,
and Executive Order 12866.

The rationale for not using draft toxicity assessments applies here - the
review process may result in adoption of different values. Premature adoption
of overly conservative draft values may create unwarranted environmental fear;
premature adoption of insufficiently conservative draft values may engender
inappropriate risk.

In addition, since the Draft TCE Risk Assessment was released in 2001,
significant new information about TCE toxicity has become available. As noted
in the attached technical memorandum prepared by Exponent, TCE toxicity was the
subject of a new science symposium sponsored by EPA in Washington, D. C. in
February 2004. Studies of TCE toxicity conducted since 2001 that were reported
at that symposium continue to indicate deficiencies in the Draft TCE Risk
Assessment warranting substantial revisions in its conclusions. As the attached
technical memorandum discusses more fully, the current state of the science on
TCE toxicity does not support continued use of the Draft TCE Risk Assessment to
assess inhalation-based risks at the MEW site or elsewhere.

Should you have questions, please call.

Sincerely,

Elie Haddad, P.E.
Vice President

--

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