SITE INFORMATION AND CORRESPONDENCE_CASE 2

Home Browse Search

Mr. Verma -3- 3 October 1994 contain the most contaminated soils from Schulte Road, and since you now seek an restricted-use designation, we must insist that the soils in these cells be shown to be inert. Please grid these cells individually, using the methods used in 1991, and sample each cell before stockpiling them together. The analyses must use methods that show no soluble components are present. Please conform, at minimum, to your consultants' original suggestion (23 August submittal) of seven samples total, which equals one sample per 500 y3 of soil -- still a very low figure. Stockpiling (compositing) the soils prior to sampling for BTXE is not acceptable; the WDRS and MRP specify grab samples. You may composite, within each cell, before sampling for TPH-d, TPH-g, TOG, and/or TRPH. Schulte Road Soils in other cells: We agree that the soils from Schulte Road that were placed in cells 2 through 6, 10 through 18, and cell 20 probably have undergone a reduction in hydrocarbon content via aeration since 1991, because they have been uncovered during most of that time. We agree that the original analyses showed low hydrocarbon content in these soils. We note, however, that the 1991 analyses did not samples soils from all of the cells listed above. To qualify for an inert classification, therefore, we require, at minimum, analyses of the cells from cells 14 and 20. You must show us that there are no remaining soluble components. The analyses must include FID. A minimum of one sample per cell, using the same grid method used in 1991, is needed. If you do not wish to do the above sampling and analysis, you may reuse the soils in cells 2 through 6, 10 through 18, and 20, without further analysis, in projects involving encapsulation and with prior approval from us. In this case, the soils will not be deemed suitable for inert classification. This statement is consistent with the conclusions of your consultant as stated in Figure 1 of their submittal dated 23 August 1994, and with the WDRs. 11th Street and Grant Line Road Soils: We understand that these soils were placed in cells 8 and 9. These soils contain gasoline and heavy hydrocarbons. There are approximately 800 y3 of these soils, according to your consultants' 23 August and 7 September submittals. (The 31 August submittal says 500 y3). We agrees that aeration has probably reduced the gasoline content, and we agree also with the proposal to test these soils for BTXE, TPH-g, and water leachable diesel. If the FID analysis shows that heavier fractions than diesel are present, we will require further evidence to show what these fractions are and whether they are leachable. The four locations for grab samples shown in Figure 1 of the 31 August submittal are acceptable. 3. Ouality Control/Ouality Assurance and Sampling Methods: The sampling proposals you have submitted do not specify whether the samples are to be "grab" or composited. The WDRS and MRP permit composited samples for TPH-d and TPH-g, and specify grab samples for BTXE. For TOG, the WDRs do not specify, and either grab or composited samples are acceptable. We require that the sampling plan specify field protocols for sampling, handling, and quality assurance-quality control. The laboratory performing the analyses must be California-certified for these procedures and must summarize its quality assurance-quality control test results with the analytical results. The