COMPLIANCE INFO - Laserfiche WebLink

Home Browse Search

L_�NCalifornia Ronal Water Quality *ntrol Board :, Central Valley Region QW; Steven T.Butler,Acting Chair Winston H.Hickox Gray Davis Secretaryfor Sacramento Main Office Governor Environmental Internet Address: http://www.swrcb.ca.gov/—rwgcb5 Protection 3443 Routier Road,Suite A,Sacramento,California 95827-3003 Phone(916)255-3000•FAX(916)255-3015 10 March, 1999 Mr. Brad Beeman ' Naval Computer and Telecommunications Station 305 Fyffe Ave., AC-43 Stockton, CA 95203 SUMP AND OIL WATER SEPARATOR AT BUILDING 617, NAVAL COMPUTER AND TELECOMMUNICATION STATION SAN DIEGO DETACHMENT, STOCKTON The Navy's letter of 16 February 1999, titled Response to Comments Regarding Sump and Oil Water Separator at Building 617, Naval Computer and Telecommunications Station San Diego Detachment, Stockton, CA proposes the Board find that no further action (NFA) is necessary for this site. This proposal is based on data from confirmation sampling of soil excavated from the former oil water separator(OWS) and associated sump located at Building 617. Based on our review of the data presented in previous documents related to Building 617, we do not agree with the Navy's NFA proposal and find investigations for groundwater contamination are necessary. Previous documents show that groundwater has been contaminated from past disposal activities related to the OWS and associated sump at Building 617. The Pre-Final UST Investigation and Corrective Measures Study, Vol. 1 & 2,for Former Underground Storage Tank Sites, dated January 1997, in part, recommends ". . . monitoring wells be installed and sampled to monitor migration and natural attenuation" of contaminants found in groundwater from HydropunchTM samples. Further, the Navy's letter of 15 September 1997, responded to the Board's "... concurrence to establish the lateral and vertical extent of groundwater contamination via GeoprobeTM or HydropunchT111 prior to installing monitoring wells." The Navy also stated that, ". . . funding is available to perform the activities proposed in the subject report." We find that these additional investigations are necessary to evaluate the existing and potential future impacts to groundwater quality at this site. The Navy's letter of 16 February 1999 included Representative Sampling Documents (page 39-40), prepared by Environmental Chemical Corporation, which described sampling and analysis of soil. Concentrations of oil and grease were detected at 150 ppm and 220 ppm, lead at 9 ppm (below background), and diesel at 11 ppm from composited samples. Grab samples were taken from sidewalls and bottom locations of the excavations and then were composited for laboratory analysis. Because the grab samples were composited prior to analysis, the data does not represent levels of contaminants which remain in place in these specific locations at this site. Mixing the soil may have masked areas of high level contaminants which could represent a significant threat to groundwater quality. However, based on the low concentrations reported and the relatively low solubility of these contaminants, we do not propose further soil sampling at this time. Additional soil investigations and/or soil removal may be necessary in the future depending upon results of groundwater monitoring. We request the Navy submit a work plan to investigate the groundwater contamination found at Building 617's OWS and sump. The work plan should include, at a minimum, a sampling and analysis California Environmental Protection Agency 0 Recycled Paper