COMPLIANCE INFO - Laserfiche WebLink

Home Browse Search

Kennedy/Jenks Consultants Section 2: Site Background 2.1 2011 Locomotive Release and Soil Removal In October 2011, a locomotive experienced a release of approximately 1,400 gallons of diesel at the Site between the mechanical shop (to the north) and the BNSF property boundary (to the south). A BNSF contractor responded to the spill. The spill response involved stopping the leak, removing the impacted railroad track, excavating the impacted soil (80 cubic yards), taking confirmation samples, backfilling, and replacing the track to its prior condition. Confirmation samples indicated residual diesel remained in soil. The approximate extent of the 2011 excavation was 60 feet long, 15 feet wide, and three feet deep, and is shown on Figures 2 and 3. 2.2 2015 Subsurface Investigation Near 2011 Soil Removal In 2015 Kennedy/Jenks prepared and implemented the Soil Investigation Work Plan, BNSF Mormon Yard, Stockton, California, to test soil and water from two borings within the 2011 excavation area to assess whether diesel impacts remained in the subsurface related to the 2011 locomotive diesel release. The investigation results from the two borings were reported by Kennedy/Jenks in Soil Investigation Report, BNSF Mormon Yard, Stockton, California. Diesel was detected in groundwater samples collected from the two borings and appeared unrelated to the 2011 diesel release due to the vertical separation of unimpacted vadose zone soil between the impacted vadose zone soil and the groundwater table. 2.3 Geotracker, EDR, and File Review The State of California Geotracker website shows two active cleanup sites with groundwater contamination near the Site. The Diamond Foods, Inc. site (shown on Figures 2 and 3) is located east of the Site and is currently monitoring shallow groundwater due to chromium releases. Northwest of the Site by more than 1/4 mile' the San Joaquin County Public Works Department maintenance equipment yard is currently monitoring and remediating groundwater due to a gasoline release. Groundwater gradient direction at both sites is northeast. In January 2016, Kennedy/Jenks conducted a file review to evaluate potential onsite and offsite diesel sources. A Radius Summary Report and historical aerial photographs were ordered from EDR (EDR Report), and a Kennedy/Jenks staff member reviewed available BNSF files for the Site at BNSF's San Bernardino office. The Site file review yielded the following documents: 1) 1989 contractor tank removal documents and county documents; 2) 1991 tank closure report; 3) notes regarding tank construction and sizes for tanks removed in 1990; 4) list including Mormon Yard tanks; and 5) a 1996 county case closure summary report. 1 The location of the San Joaquin County Public Works Department maintenance equipment yard is beyond the Site extent provided in the enclosed Figures. High Resolution Site Characterization Work Plan, BNSF Mormon Yard, Stockton, California Page 2 g:\is-group\adminob\1 311365020.01_bnsf109-reportsthrsc-wkpin text.doc