FIELD DOCUMENTS - Laserfiche WebLink

Home Browse Search

i 30 July 2008 AGE-NC Project No . 99-0682 Page 6 of 13 quarter 2008 groundwater monitoring event at the site; laboratory reports are presented in the AGE- prepared report entitled Quarterly Report - First Quarter 2008, 2.2 . 5 . Well Head Survey On 02 April 2008, a California state-licensed surveying engineer from Morrow Surveying surveyed the location and elevation of all monitoring wells; the global positioning system (GPS) location was surveyed to the nearest 0. 1 -foot relative to coordinate datum NAD 83 (1986), and the elevation at the notch in the top of the well casing was surveyed to the nearest 0 .01 -foot relative to NAVD 88 from GPS observations. The surveying report is presented in Appendix E. Confirmation numbers for GeoTracker GEO_XY and GEO_Z submittals are 3633198618 and 7127681910, respectively. 3.0. FINDINGS The stratigraphy and ground water hydrogeology underlying the site were characterized from field descriptions and the integration of the computer generated CPT lithologic logs with previous subsurface soil descriptions. This data was also used to update, expand or generate cross-sections A-A', B-B ' , and C-C ' (Figures 3 through 8). Hydrocarbon impact to ground water and soil was quantified by laboratory analysis of the ground water and soil samples. 3 . 1 . STRATIGRAPHY Based on the findings from this investigation and existing monitoring well and soil borings, cross sections A-A ' , B-B ' and C-C ' were updated or generated to depict general lithology beneath the site (Figures 3 through 8). CPT and monitoring well boring logs are provided in Appendices B and C, respectively. In CPT-6, clayey silt, silt, silty clay, and clay were inferred from 5 to 30 feet bsg, 32 to 48 feet bsg, 62 to 70 feet bsg, 74 to 81 feet bsg, 104 to 119 feet bsg, 120 to 125 feet bsg, 131 to 135 feet bsg, and 137 to 140 feet bsg. Sandy silt and clayey silt were inferred from 48 to 59 feet bsg, 81 to 104 feet bsg, and 125 to 128 feet bsg. Silty sand and sandy silt were inferred from 30 to 32 feet bsg, 59 to 62 feet bsg, 119 to 120 feet bsg, and 130 to 131 feet bsg. Sand was inferred from 72 to 74 feet bsg, 128 to 130 feet bsg, and 135 to 137 feet bsg. In CPT-7, clayey silt, silt, silty clay, and clay were inferred from 5 to 29 feet bsg, 30 to 50 feet bsg, Advanced GeoEnvironmental, Inc.