SITE INFORMATION AND CORRESPONDENCE_FILE 1

Home Browse Search

�. 11 SIERRA STANDARD OPERATING PROCEDURE SOIL SAMPLING The following describes sampling procedures used by SES field personnel to collect, handle, and transport soil samples. Before samples are collected, careful consideration is given to the type of analysis to be performed so that precautions are taken to prevent loss of volatile components or contamination of the sample, and to preserve the sample for subsequent analysis. All drilling and sampling equipment is steam-cleaned between boreholes to prevent cross- contamination. The sampler is washed with an EPA approved detergent (such as liquinox or trisodium phosphate)between sample collection. Collection methods specific to soil sampling are presented below. Soil samples are collected at pre-specified depth intervals or at a sediment/lithologic change for hydrogeologic description and possible chemical analysis. Samples are collected using a modified California split-spoon sampler lined with 2- or 2.5-inch I.D.x 4- or 6-inch long steam- cleaned or new brass tubes. The sampler is lowered into the borehole and driven 18-inches, using a 140-pound hammer. The drilling contractor provides the SES field personnel with the number of blows required to drive the sampler for each 6-inches of penetration. The sampler is then extracted from the borehole and the middle or bottom brass tube is carefully removed for possible analysis. The soil material is immediately trimmed flush with the tube ends, and sealed with Teflon tape beneath pol}-ethvlene end caps. The caps are hermeticaily sealed to the brass tube with duct tape. The sample is then labeled to include the date, boring number, depth of sample, project number, SES, and the SES field personnel's initials. The samples are put into a plastic "zip-lock' type bag and placed into an ice chest maintained below 4'C with blue ice or dry ice, for transport under chain of custody to the laboratory. The chain-of- custody form includes the project number, analysis requested, sample ID, date analysis and the SES field personnel's name. The form is signed, dated and timed by each person who yields or receives the samples beginning with the field personnel and ending with the laboratory personnel.