January 25, 2011

Sent via e-mail to: mccarthy.gina@epa.gov

Regina McCarthy

Assistant Administrator 

USEPA 

Washington DC

Re: American Petroleum Institute’s suggestions on Charge Questions to the Clean Air 

Scientific Advisory Committee Regarding Reconsideration of the March 2008 

Ozone National Ambient Air Quality Standard, Docket ID No. EPA–HQ–OAR–

2005–0172

Please find suggestions by the American Petroleum Institute (“API”) for the charge 

questions that EPA is now preparing for a review by Clean Air Scientific Advisory Committee 

(CASAC) on a teleconference on February 18, 2011 from 1:00 p.m. to 5:00 p.m. The API is the 

primary trade association of America‟s oil and natural gas industry, representing more than 450 

members involved in all aspects of the industry.

 

The API submitted comments on the U.S. Environmental Protection Agency‟s (“EPA‟s”) 

“Proposed Rule (Reconsideration) National Ambient Air Quality Standards for Ozone, Docket 

ID No. EPA–HQ–OAR–2005–0172, which was published on January 19, 2010 at 75 Fed. Reg. 

2,938 (the “Proposed Rule (Reconsideration”). API also presented comments at the public 

hearings on February 2, 2010 in Arlington, Virginia and Houston, Texas. 

On December 8, 2010 Assistant Administrator Regina McCarthy filed a declaration to the 

court (State of Mississippi, et al., v. U.S. Environmental Protection Agency, Case. No. 08-1200, 

Howard J. Feldman

Director

Regulatory and Scientific Affairs

1220 L Street, NW

Washington, DC 20005-4070

USA

Telephone 202-682-8340

Fax 202-682-8270

Email feldman@api.org

www.api.org
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D.C. Cir.) (Ozone NAAQS Litigation). In the declaration, EPA‟s plan to develop questions in 

December 2010 and January 2011 was addressed, along with the planned public meeting of 

CASAC in February 2011.

On January 26, 2011, EPA provided notice in the Federal Register of the CASAC public 

meeting, to be held as a teleconference on February 18, 2011 from 1 p.m. to 5 p.m. API has 

concerns that this consultation is being held in the format of a half-day teleconference instead of 

public meeting where the CASAC committee would have a better opportunity to benefit from 

public participation to assist in their deliberations. Further, the scope of the charge questions 

remains a mystery as we have not been able to learn from the Designated Federal Officer for 

CASAC, or OAQPS staff the likely date of release of the questions. In light of this circumstance

and to assist EPA, API prepared the following four questions that we suggest should be reviewed 

by CASAC as they consider the (old) record that you requested they review:

1. In its proposed reconsideration, EPA concluded that ambient levels of ozone cause 

cardiovascular mortality independent of other pollutants, although there is geographic 

heterogeneity in O3-associated mortality across the country. How does CASAC resolve this 

apparent lack of population dose/response?

2. EPA has relied on single pollutant epidemiological models in developing estimates 

of ozone associated risks, although there is evidence of confounding by other pollutants, such as 

PM. How does CASAC resolve this apparent multi-pollutant „double counting‟ in estimating 

ozone risks?

3. EPA has relied on a no-threshold assumption for mortality effects to estimate 

population risks and regulatory benefits far below the range of proposed ozone standards, all the 

way down to policy relevant background levels. How does CASAC resolve the predominance of 

estimated population risk at PRB levels with the relatively modest benefit of a further standard 

reduction to 60-70 ppb?
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4. EPA recomputed a statistical significance of selected 60 ppb O3 responses from the 

Adams 2006 study of 6.6 hour chamber exposures under quasi-continuous exercise. This

conflicted with the conclusions and conventional statistical approaches of the author and other 

researchers. How does CASAC resolve this departure from the accepted practice of assessing all 

of the available data?

API hopes that you will include these questions as you finalize the charge that EPA will 

submit to CASAC. Please contact me at (202) 682-8340 or feldman@api.org with any 

questions.

Sincerely,

 

/s/

Howard J. Feldman

Cc:

Steve Page (page.steve@epa.gov)

Lydia Wegman (wegman.lydia@epa.gov)