# BAKER BOlTS LL

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January 10,2011 BYFEDEX Robert J. Wayland, Ph.D. U.S. Environmental ProtectionAgency Office ofAir 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 +1202.639.7700 FAX +1202

.639.7890**www.bakerbo~s.com**

DebraJ. Jezouit TEL +1202-639-7728 FAX +1202-585-1032 debra.jezouit@bakerbotts.com DUBAI HONG KONG HOUSTON LONDON MOSCOW NEW YORK PALO ALTO RIYADH WASHINGTON

Re: Nickel SpeciationTesting Conducted at Oil-Fired Electric Utility Steam Generating Units DearBob: Enclosed for your review and consideration are three recent studies conducted for members ofthe 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 ofthese 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 ofHuman 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 (DocumentNos. 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 ofnickel compounds. At the time ofthe Utility RTC, EPA had limited information onthe 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 ofthe 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) ofthe Clean AirAct (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 categoryunder Section 1I2(c) ofthe CAA. The results ofthe three enclosed studies, as well as the prior information that we provided to you, clearly demonstrate that the risks to human healthpredicted by the Utility RTC were greatly overstated. The forms ofnickel 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 determinationinlight ofthis additional information. We appreciate your consideration ofthe informationprovided in this letter and the enclosed studies

. Ifyou have any questions aboutthe enclosed studies, please do not hesitate to contactme at 202-639-7728 orBill Bumpers at202-639-7718.

Enclosures
cc: BillMaxwell, U.S. EPA Paul Lynch, National Grid Cathy Waxman, National Grid Sincerely,

# ~ DebraJ. Jezouit

StephenWard, HawaiianElectric Company John Hampp, FloridaPower & LightCompany MaryArcher, FloridaPower & Light Company

DCO) :566681.2