June 16, 2015 

The Honorable Nita M. Lowey 

United States House of Representatives 

Washington, D.C. 20515 

Dear Congresswoman Lowey: 

 On behalf of the U.S. Nuclear Regulatory Commission (NRC), I am responding to your 

letter of May 13, 2015, concerning a transformer fire at the Indian Point Energy Center on 

May 9, 2015. Specifically, you asked for a thorough investigation of the cause of the fire and 

the safety risks it posed, an examination of the environmental health impacts, and a list and 

justification for all safety exemptions the NRC has granted at the Indian Point facility. 

 At 5:50 p.m. on May 9, 2015, with Unit 3 operating at 100 percent power, one of its two 

main transformers failed. The cause of the failure has not yet been identified. The failure 

resulted in an automatic shutdown of the reactor and an oil fire occurred in the vicinity of the 

main transformer. Plant operators declared an “Unusual Event”—the lowest of four levels of 

emergency classification for nuclear power plants used by the NRC—at 6:01 p.m. because of 

the explosion associated with the transformer failure. A fire suppression system for the 

transformer automatically doused the fire. In addition, the plant’s onsite fire brigade, with 

assistance from the Montrose and Verplank fire departments, sprayed water and foam onto the 

transformer to help put out the fire. NRC resident inspectors responded to the site, observed 

Entergy’s initial response to the fire event, and verified that the reactor was safely shutdown 

without complications. The Unusual Event was terminated at 9:03 p.m. after the fire was fully 

extinguished. 

 Main transformers are covered by the NRC’s fire protection requirements, which 

establish a “defense-in-depth” approach to prevent, detect, control, and extinguish fires. 

Specifically, fire protection systems must protect safe shutdown equipment from the impact of 

large transformer fires. Transformers typically are protected by automatic water spray systems, 

as is the case at Indian Point. 

 As part of its ongoing baseline inspection program, NRC Region I inspectors will review 

Entergy’s evaluation of the cause of the transformer failure and the plant’s response, including 

performance of the automatic shutdown systems, safety systems, and the activation of the fire 

brigade. Because there have been multiple transformer fires at Indian Point over the past 

several years, the inspectors also will evaluate possible common elements among these events, 

such as transformer monitoring and maintenance practices. These results will be published in 

future publicly available inspection reports. 

 Additionally, the NRC initiated a Special Inspection at Indian Point Unit 3 shortly after the 

transformer failure event to better understand the unexpected presence of water in an electrical 

equipment room during the event on May 9. This room contains electrical equipment that 

provides power to plant safety systems. Among other things, the NRC inspectors will be 
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reviewing whether the efforts to extinguish the transformer fire caused the accumulation of the 

water observed in the electrical equipment room. 

 With regard to environmental health impacts of the transformer fire, (i.e., the impacts of 

an oil and/or chemical release to the river), the New York State Department of Environmental 

Conservation is responsible for examining those impacts. 

 As requested, enclosed with this letter is a listing of all exemptions, including fire 

protection-related exemptions, granted by the NRC to Indian Point Units 2 and 3. The list is 

publicly available in the NRC’s Agencywide Documents Access and Management System at 

Accession No. ML12172A370. The list also is on the nrc.gov website, Indian Point page 

(http://www.nrc.gov/info-finder/reactor/ip2.html). While the list was compiled on June 20, 2012, 

it remains current as no exemptions have been granted since the list was created. The 

justification for each exemption is contained in the documents (letter or Grant of Exemption) 

referenced with each listed exemption. The NRC staff has reviewed the Indian Point 

exemptions listed in the enclosure and has determined that none of those exemptions played a 

role in the transformer failure of May 9. 

 I have directed the NRC’s Office of Congressional Affairs (OCA) to provide you with a 

copy of the referenced inspection reports when they become available. If you have any 

questions, please contact me or Eugene Dacus, Director of OCA, at (301) 415-1776. 

Sincerely, 

 /RA/ 

Stephen G. Burns 

Enclosure: 

As stated