WORK PLANS - Laserfiche WebLink

Home Browse Search

3.2 3.3 2. The samples will be retained in the sample liners with the ends covered with aluminum foil or Teflon® sheets and plastics end caps. If a split spoon sampler is used, clean brass liners will be inserted into the sampler prior to lowering the sampler to the bottom of the borehole. The sampler will be driven into the undisturbed soil ahead of the lead auger by repeatedly dropping a 140 -Ib hammer with a 30 -inch drop on the drill rods connected to the split spoon sampler. The sampler with its sample will be retrieved once the sampler is driven 18 -inches into the undisturbed soil or refusal is encountered (i.e., the sampler advances less than 6 inches over 50 drops of the hammer). If a 5-11 core barrel is used, a subsample will be collected from the core by pushing or driving a 2 -inch diameter brass liner into the core until both ends of the liner are filled with sample. Soil Boring and Soil Sampling Using a Geoprobe, Stratoprobe or Equivalent Hydraulic -Push and Vibratory Rig Shallow soil borings (i.e., generally less than 30 ft) may be advanced and sampled using a truck -mounted Geoprobe or Stratoprobe rig which uses hydraulic pressure and sometimes vibratory energy to advance and sample subsurface soils. Samples of the subsurface soils will be continuously cored using a 2 -inch O.D., 4 -ft long, tubular steel sampler. Soil samples will be retained in the sampler in 1.75 -inch diameter, 46 -inch long, transparent acetate liners. Each sample drive is about 4 ft in length, and sampling is performed in consecutive, 4 -ft intervals. The following procedures will be used for collecting soil samples using a Geoprobe (or similar) rig: 1. Prior to sampling, the Geoprobe soil sampler will be steam cleaned or thoroughly washed with a solution of Alconox or non -phosphate TSP and double rinsed with potable water. The sample liners will be new from the factory in their original shipping carton, and will not require washing. Selected soil samples collected at various depths will be retained in the sample liners (the sample liner containing the desired sample will be cut into a 12 -inch or shorter length with a clean knife blade or clean hacksaw blade), and the ends covered with Teflong sheets and plastic end caps. Borehole Abandonment Procedures After the soil samples have been collected from each soil boring, the boreholes not used for well construction will be pressure grouted to the surface using Regenesis® ORC cement. The cement will be pumped into the borehole using a high pressure, horizontal injector tool. 402 331-98 63 A-2