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Sr?p-r 21 —98 05 : 14P CytoCulture Report on Batch Inoculation and Gallery installation 2 LAGCO Site, Mountain View, CA for Norcal Waste Systems, Inc. December 19, 1995 the clay layer Specific geology and stratigraphy characteristics will become more evident during the ongoing over-excavation work, but it would appear that the contaminated groundwater should be fairly accessible by intercepting trenches penetrating down into the saturated sand layer below 10 ft bgs Following the short term bioremediation feasibility study, Emcon reported diminished levels of nutrients and oxygen, and a relatively low background population of hydrocarbon- degrading bacteria by their assay (details not specified) of approximately 4,700 colony forming units per milliliter (cfu/ml) Although these data are encouraging for the potential stimulation of the in situ bioremediation activity by enhancing the nutrient and oxygen levels of the subsurface environment, Emcon's own data suggested little change in the popu cation of the indigenous strains of hydrocarbon degrading bacteria after their one week trial On the other hand, there was a credible decrease in the dissolved phase gasoline hydrocarbons over a period of over 3 weeks in the vicinity of the test well, MW-6 On Monday, December 8, 1995, CytoCulture mobilized a 2,000 gallon batch culture reactor at the Los Altos Garbage Company (LAGCO) site in Mountain View The equipment was • stored in the south east corner of the yard until the start-up of the batch culture for the inoculation of the excavation Tuesday December 12, 1995 was the start up date for the batch culture Utilizing mo submersible sump pumps and 1 5" fire hose, 2,000 gallons of groundwater and rain run-off water was pumped into the 2,000 gallon bioreactor Additions of ammonia and phosphate macronutnents, pH buffers and a vegetable oil based carbon source were made to the: reactor prior to seeding the culture with selected strains of hydrocarbon-degrading bacteria A 150 cfm regenerative blower was used to aerate and suspend the growing bacterial cultures The batch reactor was allowed to operate and culture bacteria for approximately 50 hour: prior to spraying the inoculum into the excavation as described in the Work Plan of Decembar l I Installation of Extraction and Infiltration Galleries Peter Hudson of Fugro West, Brent from Ramcon and John O'Bannon from CytoCulture mobilized on site Thursday, December 14, 1995 Due to the significant amount of rainfall the Bay Area experienced from Sunday through Wednesday, the excavation contained approximately 3 feet of rain runoff water Knowing that the excavation was collecting a large amount of runoff, CytoCulture secured permission from the Mountain View Environmental Safety Division, to dewater the excavation of accumulated groundwater Under supervision from Fugro West, a 3" centrifugal pump was set up and the excess rain water was rt-moved from the excavation to the sanitary sewer During the dewatering operation, Ramcoii's operator mobilised a back hoe for the construction of the galleries CytoCulture constructed the horizontal piping and vertical risers for the infiltration and extraction galleries