20160906AVU to Staff 138.doc

AVISTA CORPORATION
RESPONSE TO REQUEST FOR INFORMATION

JURISDICTION: IDAHO DATE PREPARED: 09/01/2016
CASE NO.: AVU-E-16-03 WITNESS: Liz Andrews
REQUESTER: IPUC RESPONDER: Ryan Finesilver/Heide Evans
TYPE: Production Request DEPARTMENT: State & Federal Regulation
REQUEST NO.: Staff - 138 TELEPHONE: [phone]

REQUEST:

For each of the environmental cleanup costs listed on the Company’s response to Staff Production Request No. 9, please provide a brief explanation of the event and how those costs were allocated to Avista’s jurisdictions.

RESPONSE:

Please see Staff_PR_138 Attachment A for the jurisdictional allocations.

Hamilton Street – Coal tar contamination from Spokane Natural Gas Company’s previous operations

When the Hamilton Street bridge was constructed by the Washington Department of Transportation in the 1980s over the parcel, contaminated soil was discovered. The investigation led to Avista, BNSF and Spokane River Properties (Brown) being named as Potentially Liable Parties by the Washington Department of Ecology (Ecology). Ultimately, Avista and BNSF entered into a Consent Decree with Ecology to implement a Cleanup Action Plan, including long-term institutional controls and site monitoring. Avista implemented its remedial action responsibilities under the Consent Decree, and continues to comply with the Consent Decree via ongoing monitoring and reporting, subject to Ecology’s ongoing oversight.

Kettle Falls Generation Station - Diesel Spill Investigation and Remediation

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 appropriate 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, which has been in operation and is successfully remediating the site.  Between December 2013 and December 2014, the Company recorded and expensed a remediation liability. The Company has continued to monitor the remediation expense activities and adjust any estimated remediation liability if necessary as new information is obtained. No additional remediation expense was recorded during 2015 related to this project and therefore no additional expense in 2015 was included in the Company’s filing.

Northeast Combustion Turbine Site

In August 2005, a diesel fuel release 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 release occurred when Co-op made a delivery of diesel to a tank that was already nearly full and the extra fuel overflowed into the surrounding containment area.

An investigation, supervised by the Washington Department of Ecology (Ecology), 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 present at a depth of about 170 feet. Ground water monitoring wells were developed and subsequently monitored for contamination. Results of the monitoring showed that groundwater was not impacted. Remedial efforts included the removal of contaminated soil from the impacted area and the permanent removal of related fuel storage facilities.

A soil vapor extraction/biovent (SVE) system was installed and was operational from July 2006 through January 2008. In 2014, a limited site assessment was completed to determine if residual contamination remained at concentrations exceeding applicable cleanup standards.

In general, the results of the assessment showed that contamination was not observed or did not exceed applicable cleanup criteria. Avista entered into a Voluntary Cleanup Program agreement with Ecology and a No Further Action opinion was provided by Ecology for the site in 2015.  Site grading and offsite removal of soil in the controlled bioremediation area that had previously been removed from the impacted area remain and are scheduled for October 2016. No remediation expense was recorded during 2015 related to this project and no expense was included in the Company’s filing.

Wa Distr Environmental Maint / Id Distr Envronmental Maint / Electric Environmental Expense

Costs included in this project include miscellaneous environmental events such as small spills or events that result in the need for mediation including acts of god, auto/vandal, equipment failure, etc.

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