Laserfiche WebLink
The Morton Paint Company formerly owned Area III. Currently Snow Cleaners, <br /> Incorporated, owns Area III and operates a leather cleaning business on the property. <br /> The surface topography of the area is relatively flat with a gentle downward slope <br /> towards the west. The surface elevation of the Site is approximately 15 feet above <br /> mean sea level (Figure 1). The Mormon Slough is located west and south of the Site <br /> across from Hazelton Avenue. The Port of Stockton is located less than 1.5 miles west- <br /> northwest from the Site. <br /> 2.3 Geology and Hydrogeology <br /> Stockton lies within the Central Valley (a 400-mile long and 50-mile wide northwest <br /> trending structural trough) at the eastern margins of a deltaic fan region formed by the <br /> intersection of the Sacramento and San Joaquin Rivers with the San Francisco Bay. <br /> The Central Valley is bordered to the east by the Sierra Nevada and to the west by the <br /> Coast Ranges. The sediments deposited in the Central Valley from these two ranges <br /> include both marine and continental gravels, sands, silts and clays. <br /> Three hydrogeologic zones have been designated at the Site. Zone A, the upper 60 <br /> feet, consists of fill (mainly sandy clay in the upper 25 feet) underlain by clay and silt. <br /> Zone B, from 60 to 160 feet below ground surface (bgs), consists predominantly of <br /> alternating sand and low-permeability silt and clay units. Zone C, generally between 160 <br /> feet and 210 feet bgs, consists of clay underlain by a series of thick sand, sandy gravel, <br /> and gravelly sand units locally interbedded with silt and sand. Groundwater is <br /> encountered at the Site at a depth of approximately 25 feet bgs. <br /> Groundwater in Zone A is unconfined. Groundwater occurs under semi-confined <br /> conditions in Zones B and C. Horizontal groundwater flow directions are generally to the <br /> east in the three zones at very low hydraulic gradients. Water levels at the Site show <br /> small but consistent downward vertical gradients between the three zones. <br /> Groundwater levels since 1998 have been approximately 20 to 25 feet higher than the <br /> groundwater levels observed in 1992. Groundwater levels in the area also fluctuate <br /> seasonally. <br /> 4 ENV,^; <br /> A M E R I C A <br /> P:\PGSE\PGE-05-01 Stockton MW26R Investi9abo6MW26 Work Plan\PGE Stockton MW26R WP.doc <br />