BAKER BOlTS LL.P 

January 10,2011 

BY FED EX 

Robert J. Wayland, Ph.D. 

U.S. Environmental Protection Agency 

Office of Air Quality Planning & Standards 

MD C439-01 

Research Triangle, Park, NC 27711 

THE WARNER ABU DHABI 

1299 PENNSYLVANIA AVE .. NW AUSTIN 

WASHINGTON, D.C. BEUING 

20004-2400 DALLAS 

TEL + 1 202.639.7700 

FAX + 1 202.639.7890 

www.bakerbo~s.com 

Debra J. Jezouit 

TEL + 1 202-639-7728 

FAX + 1 202-585-1032 

debra.jezouit@bakerbotts.com 

DUBAI 

HONG KONG 

HOUSTON 

LONDON 

MOSCOW 

NEW YORK 

PALO ALTO 

RIYADH 

WASHINGTON 

Re: Nickel Speciation Testing Conducted at Oil-Fired Electric Utility Steam 

Generating Units 

Dear Bob: 

Enclosed for your review and consideration are three recent studies conducted for 

members of the Class of '85 Regulatory Response Group regarding nickel emissions from oilfired electric utility steam generating units (EUSGUs). These three studies demonstrate that 

there is effectively no sulfidic nickel being emitted by the oil-fired EUSGUs that were tested. 

The results of these studies are consistent with the results in the previous report we provided to 

you that was prepared by the Energy and Environmental Research Center at the University of 

North Dakota entitled "Nickel Species Emissions Inventory for Oil-Fired Boilers" and the paper 

published in 2004 by Christopher M. Teaf, Bruce J. Tuovila, Edward J. Zillioux, Annette Shipp, 

Greg Lawrence and Cynthia Van Landingham in the Journal of Human and Ecological Risk 

Assessment entitled "Nickel Carcinogenicity in Relation to the Health Risks from Residual Oil 

Fly Ash." Both of these documents were included in the docket for EPA's 2004 proposed 

national emissions standards for hazardous air pollutants for electric utility steam generating 

units (Document Nos. OAR-2002-0056-0018 and OAR-2002-0056-5284). 

In EPA's February 1998 Study of Hazardous Air Pollutant Emissions from 

Electric Utility Steam Generating Units - Final Report to Congress (Utility RTC), EPA 

estimated that 11 out of 137 oil-fired EUSGUs would pose inhalation cancer risks greater than 

one in one million based on their emissions of nickel compounds. At the time of the Utility 

RTC, EPA had limited information on the nickel species emitted from oil-fired EUSGUs. Based 

on an indirect speciation method known as "sequential nickel extraction," which has since been 

invalidated, EPA projected that up to 26 percent of the nickel emitted from oil-fired EUSGUs 

was nickel subsulfide, the most carcinogenic nickel species. On the basis of those data, in 

determining the risk posed by oil-fired EUSGUs, EPA conservatively assumed in the Utility 

RTC that the nickel emissions from oil-fired EUSGUs were 50 percent as carcinogenic as nickel 

subsulfide. 

Based on these assumptions and the invalidated nickel speciation tests, EPA 

determined that it was appropriate and necessary pursuant to Section 112(n)(I)(A) of the Clean 

Air Act (CAA) to regulate nickel emissions from oil-fired EUSGUs and to list oil-fired EUSGUs 

DC01 :566681.2 
BAKER BOlTS LLP 

Mr. Robert Wayland - 2 - January 10,2011 

as a source category under Section 1I2( c) of the CAA. The results of the three enclosed studies, 

as well as the prior information that we provided to you, clearly demonstrate that the risks to 

human health predicted by the Utility RTC were greatly overstated. The forms of nickel emitted 

by the oil-fired EUSGUs that were tested either are not shown to be carcinogenic or are not 

likely to be bioavailable. See Nickel Carcinogenicity in Relation to the Health Risks from 

Residual Oil Fly Ash. This calls into question the determination that EPA made pursuant to 

Section 112(n)(1)(A) of the CAA that it was appropriate and necessary to regulate oil-fired 

EUSGUs under Section 112 and we request that EPA re-evaluate and revise its appropriate and 

necessary determination in light of this additional information. 

We appreciate your consideration of the information provided in this letter and the 

enclosed studies. If you have any questions about the enclosed studies, please do not hesitate to 

contact me at 202-639-7728 or Bill Bumpers at 202-639-7718. 

Enclosures 

cc: Bill Maxwell, U.S. EPA 

Paul Lynch, National Grid 

Cathy Waxman, National Grid 

Sincerely, 

Debra 

~ J. Jezouit 

Stephen Ward, Hawaiian Electric Company 

John Hampp, Florida Power & Light Company 

Mary Archer, Florida Power & Light Company 

DCO) :566681.2