Clarifier Soil Sampling Work Plan - Phase 2

Transcription

1 Clarifier Soil Sampling Work lan - hase 2 GM GS Bedford Facility 105 GM Drive Bedford, Indiana E ID# IND OC Docket No. RCR GHD 6400 Shafer Court Suite 400 Rosemont Illinois US Report No 413 July

2 Table of Contents 1. Introduction Scope of Work Schedule Reporting... 2 Figure Index Figure 1 Soil Boring Locations GHD Clarifier Soil Sampling Work lan - hase (413) age i

3 1. Introduction This report presents work plan for the scope of work for the second phase of the Clarifier Soil Sample program at the General Motors Global ropulsion Systems Bedford Facility (GM) in Bedford, Indiana. The work plan presents additional sol borings to be advanced near Former South Lagoons #1, 2, and 3. The purpose of the additional sampling program will be to Determine the CB concentrations of subsurface soils in the area of the former lagoons to ensure the planned surface restoration is suitable to prevent direct contact to the underlying material and provide long term protection against erosion and related transport of contaminants. Evaluate the potential for NL in the soil above the bedrock Collect waste characterization samples The location of the initial borings, along with the preliminary CB results are shown on Figure 1 (including samples collected by facility personnel). Figure 1 shows eight additional borings that will be advanced to a total depth of 6 feet below ground surface (bgs) (blue circles). Two borings within each of the former lagoons (a total of six deep borings) will be advanced to top of bedrock or probe refusal, estimated to be 20 feet bgs (pink circles). Three of these six deep borings will be a continuation of a shallow boring advanced during the first phase of the investigation (borings -11, -2 and 4). sixth deep boring will be advanced south of the existing Filter Building. Soil samples will be collected at 2 foot intervals up to 8 feet bgs in the deep borings in the three new deep borings and intervals starting after the sample depths collected in the adjacent hole in the hase 1 sampling (up to 8 feet bgs) of the remaining deep borings. dditional samples will be collected in intervals of heavy staining below that depth and analyzed for total CBs. composite sample from the upper 6 feet of the shallow borings will be collected for waste characterization. If NL or water is encountered, collection of a sample of the NL or water will be attempted at the interface. 2. Scope of Work The required tasks are as follows: Work will be completed under the site Health and Safety lan. re-task plans will be reviewed by project personnel, including GM, prior to initiating the work. Ground enetrating Radar Systems (GRS) of Indianapolis, Indiana will perform the utility locates for the proposed boring locations. GHD will also request a GM representative familiar with the work area to review the proposed boring locations. GHD will retain the services of a qualified drilling firm to perform the drilling services. GHD geologist will oversee soil boring advancement activities. The drilling subcontractor will use air knife vacuum excavation technology to advance borings on the west side of GM Drive. Locations will be cleared to a total depth of 6 feet bgs. GHD will GHD Clarifier Soil Sampling Work lan - hase (413) age 1

4 continuously log locations to the total proposed depth. hotoionization Detector (ID) will be used to screen the soil in 1-foot intervals. Soil samples will be collected in 2 foot intervals from surface to the end of the boring. Soil samples will be collected using a hand auger. The hand auger will be decontaminated between each sample location. The drilling subcontractor will use a Hollow Stem uger drill rig to advance the soil borings to top of bedrock at the deep boring locations. The air knife will be used to clear the top 6-feet to insure no underlying utilities. Blow counts will be collected during soil boring advancement for geotechnical purposes. GHD will continuously log the location until top of bedrock is encountered. hotoionization Detector (ID) will be used to screen the soil in 1-foot intervals. Soil samples will be collected in 2 foot intervals from surface to the end of the boring. Samples will be placed in a pre-cleaned lab-supplied container. Sample containers will be labeled indicating the unique sample ID, sample date, sampler name, and parameters being analyzed. The samples will be shipped in a cooler packed with ice, under chain of custody protocols to Test merica Laboratories Inc. (Test merica) in North Canton, Ohio. Soil samples will be analyzed for total CBs. Temporary wells (1-inch VC pipe with a slotted well screen) will be placed in the deep borings. The wells will set overnight. Fluid levels will be recorded using an oil/water interface probe. Water and/or NL sample collection will be attempted if present in sufficient quantities. Once measurements and observations are recorded, the temporary well will be removed. Bledsoe Riggert Cooper James (BRJC) of Bedford, Indiana will mark the proposed sample locations. Sample locations may be adjusted based on the results of the utility locate. BRJC will survey the final soil boring locations. Results will be used to evaluate the area to be capped, potential worker exposure during decommissioning activities, assess the potential for NL presence and to characterize the soils which will remain in place after decommissioning is complete. 3. Schedule The sampling activities included in this Work lan are anticipated to be completed during the third quarter of Reporting The updated status of the sampling activities will be included in the currently on-going quarterly progress reports. Soil Sampling report, which will include the results from the first and second phases of the investigation, will be prepared following completion of the sampling activities, and receipt and compilation of the data from the laboratory. GHD Clarifier Soil Sampling Work lan - hase (413) age 2

5 roposed boring, M.H. 0-6 feet ppm ppm -8 K8 C.B ppm ppm roposed boring, to refusal/bedrock Existing boring to additional depth, to refusal/bedrock -12 K K ppm 2-4 (gravel) -11 Stone Finish: nis is 12" compacted act ct d clay cte cla ay 60-mil LLDE E E Liner Lin iner er Drainage nage Geonet Geon onet n 12" common fill 6" crushed stone -3 K ppm ppm Chemical Building Boring locations and depths are subject to 200 modification based on actual conditions -10 K ipes to remain in service -1 K1 2-2 New pipe to be installed " G.. M.H. G ppm ppm Existing Concrete e Su Surface Sur B ppm ROIMTE GM ROERTY BOUNDRY ppm ppm B ppm m Filter Building 48" ppm ppm B ppm C.B. 36" B ppm New EQ New EQ tank ta nkk pad pad pa ppm ppm B rop ropo roposed r C.B. Truck ru u k Rated Concrete n nc aving a a ing GT-1ace Surface e Ra Raw aw ww Wa Waste ste e Building Bu ild din ng g ppm ppm 24" ppm ppm ft ppm ppm ' boring, data >50 ppm ppm ppm 0 0-4' boring, data <50 ppm ppm ppm LEGEND EISTING GROUND SURFCE ELEVTION CONTOURS (feet MSL) FENCE LINE SOIL BORING LOCTION ND IDENTIFIER (RES012)GN-CO002 JUL 12, ONDS figure 1 SOIL BORING LOCTIONS GM CET BEDFORD FCILITY

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