20150904AVU to Staff 137.doc

AVISTA CORPORATION
RESPONSE TO REQUEST FOR INFORMATION

JURISDICTION: IDAHO DATE PREPARED: 09/01/2015
CASE NO.: AVU-E-15-05/AVU-G-15-01 WITNESS: Don Kopczynski
REQUESTER: IPUC RESPONDER: Heidi Evans
TYPE: Production Request DEPARTMENT: Environmental Affairs
REQUEST NO.: Staff - 137 TELEPHONE: [phone]

REQUEST:

For each of the three environmental cleanup projects listed below (see Company response to Staff Production Request No. 10), please provide a brief explanation of the event, the process for the environmental cleanup, the accounting treatment of costs associated with the cleanup, and the allocation between jurisdictions.
Kettle Fall Fuel Spill
NE Oil Tank Spill Cleanup
KFGS Diesel Fuel Spill

RESPONSE:

a. & c. Kettle Falls Generation Station - Diesel Spill Investigation and Remediation (these are the same spill)

In December 2013, the Company's operations staff at the Kettle Falls Generation Station discovered that approximately 10,000 gallons of diesel fuel had leaked underground from the piping system used to fuel heavy equipment. Avista Corp. made all proper agency notifications and worked closely with Ecology during the spill response and investigation phase. The Company installed ground water monitoring wells and there is no indication that ground or surface water is threatened by the spill.
Ecology did not initiate an enforcement action; however the Company initiated a voluntary cleanup action with the installation of a recovery system.
As of December 31, 2014, the Company has recorded an estimated remediation liability and the Company will continue to monitor the remediation activities and adjust any estimated remediation liability if necessary as new information is obtained.

b. Northeast Combustion Turbine Site

In August 2005, a diesel fuel spill occurred at the Company’s Northeast Combustion Turbine generating facility (Northeast CT) located in Spokane, Washington. The Northeast CT site had fuel storage facilities that were leased to Co-op Supply, Inc., an affiliate of Cenex Cooperative (Co-op). The fuel spill occurred when Co-op made a delivery of diesel to a tank that was already nearly full and the extra fuel overflowed into a containment area. It is estimated that approximately 26,000 gallons of fuel escaped the containment area and leaked into the soil below it. An investigation, supervised by the DOE, determined the fuel was, for the most part, uniformly present in the soil to a depth of 30-35 feet. Groundwater below the site is at a depth of 170 feet. Remediation efforts included the removal of contaminated soil and the related fuel storage facilities.

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