Laserfiche WebLink
DER <br /> Bright Bright People.Right Solutions. <br /> 1 PROJECT BACKGROUND <br /> Foothill Sanitary Landfill is owned and operated by San Joaquin County, Department of <br /> Public Works, Solid Waste Division. The Test Pad was constructed on Module I during <br /> summer 2006, and monitoring began in mid-November of that year (Plate 2 and 3). The <br /> Test Pad was constructed with a 30 mil PVC liner, geotextile, geonet, bio-barrier, and <br /> approximately 4'/2 feet of soil cover (Plates 4, 5, and 6). During spring and summer <br /> 2007, the native plant seeding (completed in fall 2006) was found to be inadequate <br /> (failed). The growth was spotty, showing weak or no growth over a significant portion of <br /> the evapotranspiration final cover (ET Final Cover) within which the Test Pad is located. <br /> It was believed that a misapplication of a seed mix additive (mycorhizal fungal product) <br /> was the cause for the poor growth, coupled with a dry rainfall year. The surface of the <br /> ET Final Cover was reseeded in fall 2007 using the same mixture as used in 2006, but <br /> this time with correct application of the mycorhizal fungal additive. <br /> The reseeding in 2007 did not appear to resolve the situation, and during 2008, the <br /> same spotty growth patterns were observed. In fall 2008, the surface of the ET Final <br /> Cover was again reseeded but supplemented with an organic soil amendment and <br /> fertilizer. The soil amendment and fertilizer were tilled into the surface soil, and the area <br /> was then reseeded. The approach used in this last reseeding was successful. Growth <br /> of native plants on the surface of the ET Final Cover is more dense and uniform. There <br /> are a few small areas of limited growth where it appears that the seed drill (device used <br /> for the seeding and reseeding efforts) malfunctioned and did not place seed. These <br /> small areas were hydroseeded in early spring 2009, resulting in new growth. <br /> This growth remained strong through 2009 and into the 2010 rainy season. 2010 saw <br /> much more rain than previous years, resulting in overgrowth of California Brome. Sheep <br /> were brought onsite during late spring 2010 to control this overgrowth and allow the <br /> purple needle grass to thrive. <br /> The ET Final cover is monitored with a weather station (west station), soil moisture <br /> probes, seepage collection (pan lysimeter), and surface water run-off collection system <br /> (Plate 7). Run-off is collected in a sedimentation tank equipped with a dosing siphon <br /> 47717.11/STO1 OR310 Page 1 of 8 August 31, 2010 <br /> Copyright 2009 Kleinfelder <br />