ARCHIVED REPORTS XR0000988 - Laserfiche WebLink

Home Browse Search

Vallev Water Treatment Page 3 Groundwater Monitoring Well Construction ' Project No. 480.2 Mardi 14, 2006 ' 2.0 FIELD INVESTIGATION The following sub-sections describe the work completed on and near the subject ' site. 2.1 Soil Borings & Monitoring Well Construction ' Four groundwater monitoring wells (designated as MW-1 through MW-4) were drilled and constructed. ' 2.1.1 Soil Boring Drilling On December 1, 2005 a BK-81 hollow stem auger drilling rig, owned and operated by V&W Drilling Inc. (C-57 #720904), was used to drill four soil borings (designated as MW-1, MW-2, MW-3 and MW-4). The borings were advanced to a total depth pf 20 feet. While drilling, all soil cuttings were placed ' in steel drums, pending profiling and proper disposal. The borings were drilled using 8-inch diameter hollow stem auger tools. Soil 1 samples were collected during the drilling process to assist in logging the borings, and for possible laboratory analysis. ' . 2.1.2 Soil Sample Collection Procedures During the drilling process, soil samples were collected for geological and ' analytical evaluation at five-foot intervals using a 2.0-inch diameter (i.d.) California split spoon sampler with the samples contained in 2 by 6-inch stainless steel liners. The sampler was driven up to 18 inches into the native soil using the 140-pound slide hammer mounted on the drill rig. The blow count was recorded for each sample collected. All soil samples were sealed with aluminum foil, capped, labeled and placed in a cooler at 4° Celsius for transport ' to the laboratory following Chain of Custody protocol. Boring logs of soils encountered in each boring were kept by a professional geologist working under the supervision of a California Professional Geologist (Appendix B). Recorded in these logs were notes on sampling intervals, boring locations and sediments intersected by the boring. Not all soil samples collected ' were submitted for laboratory analysis. Accordingly, a field screening procedure was used to select those samples that were to be tested. Special attention was paid to sediment type, color, grain size, sorting, and odor. 2.1.3 Monitoring Well Construction After drilling, the borings were converted to monitoring wells. They were constructed as originally proposed in the Work Plan. The wells were cased with 2.0-inch diameter, schedule 40 PVC casing with flush threaded joints. The N2937 Veneman Ave.,#B240 Geo-Phase Environmental Inc. Phone (209) 569-0293 Modesto, CA 95356 Fax (209) 569-0293