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Ms.Ma*Lagorio • November 10,2000 Page 3 Classification System (USCS). Selected samples will be collected for.physical characteristics. The sampler will don new disposable nitrile gloves prior to handling each sample. Upon retrieval,the sample sleeve will be capped by Teflon sheets and plastic caps,labeled with the site name, sample identification, sample depth, date and time of sampling, and initials of the sampler. The sample will be placed in a sealable plastic bag and placed on ice in a cooler pending transportation to the laboratory. The sample information will also be logged on a chain of custody form along with the analyses to be run. The chain of custody will accompany the samples from the time of collection to delivery to the laboratory. Soil Sample Analysis Soil samples from the saturated zone will be processed and labeled as described above for analysis of physical parameters in the saturated zone from each distinctive soil type encountered beneath the water table (maximum of four samples). The soil samples will not be analyzed for chemical parameters other than total organic carbon. The physical parameter analyses shall consist of: • Particle Size Distribution: (1/4" to 0.4 micron range ASTM D422/4464) • Total Organic Carbon(Walkley-Black) • Capillary Pressure Package: Air/water; centrifugal method, includes: multi-point capillary pressure (characteristic) curve, porosity (effective), bulk/grain density, and permeability to air and water. Well Development Initial well development will be conducted immediately after placing the filter pack by surging to settle the filter pack prior to placing the bentonite transition seal. At least 24 hours after well installation, the well will be developed by surging and pumping or bailing until physical parameters such as pH,temperature, and conductivity stabilize and the water appears clear. If the subsurface soil is comprised primarily of fines,it may not be possible to achieve low levels of turbidity. Purge water will be stored in labeled drums pending characterization and appropriate disposal. Well Survey and Sampling The top of casing of each well will be surveyed for northings, castings, and elevation by a California licensed surveyor. The ground elevation will also be determined at each well. Groundwater levels will be measured with an electric water level meter prior to sampling. The probe will be decontaminated between groundwater monitoring wells. Measurements will be taken from the surveyed reference point marked on the top of the PVC risers. Water-level measurements will be taken within 0.01 foot and recorded in the field notebook or on field sampling sheets. Prior to sampling each groundwater monitoring well, the water level will be measured and the volume of water in the well casing will be calculated. A minimum of three well casing volumes will be purged using a bailer or submersible pump. During the purge cycle, field measurement of pH,specific conductance,temperature,and visual observations will be recorded to verify well stabilization. To collect a representative water sample, stabilization will be deemed complete P:\20000\20587\WKPINweHs 1.&c