Laserfiche WebLink
October 2000 -29- 003-2191 <br />3.2.2 (B) Depth to and Thickness of Perched Zones and Uppermost Aquifer <br />The first occurrence of groundwater near the site vicinity is in the shallow Dawson <br />azkose bedrock. In general, the units of the Dawson azkose thought to be most capable <br />of transmitting groundwater aze the sandstones because they aze expected to have higher <br />petmeabilities than surrounding bedrock materials (i.e., claystones). The sandstone <br />units within 260 feet of the surface in the Dawson are of transitional composition due to <br />the depositional envirotunent. The strata ware mainly deposited from wind and water <br />erosion as the Rocky Mountains were uplifted. Consequently, the sandstone sequences <br />are not extensively defined over a large area. <br />Specific to the site, a dominant sandstone was identified by the site drilling program <br />which was observed in all of the monitoring well borings. For purposes of this <br />discussion, the sandstone is referred to as the A Sand and does not appeaz to be water <br />bearing. An attempt was made to correlate the A Sand across the property as shown in <br />the generalized cross sections of Figure 4. The A Sand may not be connected between <br />wells M-5 and M-6. Immediately underlying the A Sand is a series of claystones, <br />lenticulaz sandstones, and other transitional strata which aze relatively impermeable or <br />contain little or no water. <br />The uppermost saturated zone (or zones) has been identified and established at the site <br />in a sandstone member beneath the A Sand and transitional strata. This sandstone, <br />referred to as the B Sand, was observed in each of the monitoring wells except M-2. M- <br />2 was not drilled deep enough to intercept the B Sand. The upper surface of the B Sand <br />dips from east to west. B Sand elevations across the property range from about 5800 <br />feet (east boundary) to approximately 5760 feet (west boundary). Observed water <br />levels in the site wells aze above the top of the B Sand indicating that water is under <br />slightly confined conditions. This is most evident in M-6 neaz the southeast comer of <br />the site. A summary of the observed water levels in each of the wells is as follows. <br /> <br />WM1191R19~SaEJiWami~1000 doc Sedalia Recycling Center and Depository <br />