Penoyer_2004_FormerChevronShoreBasedFacility

Penoyer, Pete

Arlene Wimer recently sent me a copy of a letter (dated June 16. 2004) from ChevronTexaco to Superintendent Jock Whitworth of PAIS NS dealing with the abandoned (1985) Chevron Shore Base facility. ChevronTexaco had received a site closure release in 1986 but subsequently volunteered to do surface soil remediation to permit native vegetation to return to the site (located near the historic Line Camp). Recent soil sampling data suggest there has been a significant decline in TPH in the site soils due to remediation (largely impacted soil removal. backfill of an excavation with clean soil, and follow-on tillage of remaining impacted soils. ChevronTexaco has provided some documentation of the return of native grasses in pictures (Park staff may Wish to confirm this visually however). In the letter, ChevronTexaco reiterate that site closure was accepted on October 2. 1986 (pre-19H regulations) and that with the surface is largely restored vegetatively (70% was the agreed to goal) with final lab results of soil TPH provided in this correspondence (no lab specific treatment threshold for TPH was agreed to in this voluntary effort). Because of the long history of hydrocarbon gathering/processing at this site, there is the potential for remaining ground water contamination which Chevron (at the time) chose not to investigate before gaining a release. Gary and I have discussed the recent letter and are not aware of any mechanism to cause ChevronTexaco to conduct a ground water investigation at the site. Also, apparently there may have been some geophysical work done at the site by Park contacts at Oklahoma State University indicating a resistivity response suggesting free product may exist In the subsurface (correct me if I am wrong here Arlene). To confirm the presence or absence of remaining contamination in site ground water, direct push sampling or monitoring well installations may be required. Given the legal situation, it does not appear that this site is likely to have any further investigation to confirm ground water is not impacted unless NPS is prepared to pick up the cost. Since no groundwater discharges with impacts to ecological receptors are apparent over the last 18 years since site closure, further investigation may not be warranted, despite the potential for some free product remaining on the water table. Please advise. We would be happy to discuss this site and ChevronTexaco's opinion that the site is now "successfully restored" in conference call tomorrow afternoon (Thurs) or some later date at your convenience. Please email reply to all and I can set up a call-in # for those who wish to participate.