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SCOPE OF WORK TASK ONE: MONITORING WELL INSTALLATION Task 1:1- Soil Borings One boring will be drilled and will be converted to a groundwater monitoring well at the locations shown on Figure 1. Drilling and well installation permits will be secured from the PHS-EHD. Wright will prepare a site specific health and safety plan, notify Underground Service Alert, and preform utility location prior to the start of field work. Boring for the monitoring well will be installed by the use of a truck- mounted ruckmounted hollow stem auger. The sampler will be advanced to the desired sampling. depth interval, and a soil sample core collected. The boreholes will be logged using the United soils Classification System under the supervision of a registered geologist using the Wright Sampling Geoscience Protocols. (see Attachment B). The samples will be collected at a minimum of five foot intervals, at intervals of obvious contamination and at stratigraphic features of interest. Additional lithologic information will be collected to describe the subsurface geology at the discretion of the supervising geologist. Selected samples may be field tested using the Hanby TM Field Colorimetric Test, a semiquantitative field laboratory test for presence of hydrocarbons. These tests provide rapid reconnaissance data on estimated hydrocarbon concentrations presenting soil and groundwater. The ultimate well depths are estimated to be 15 to 25 feet. When soil samples are retained for laboratory chemical analysis the sampler will be equipped with clean stainless-steel or. brass liner will be sealed with TeflonTm paper, and plastic endcaps. All samples will be-immediately labeled, logged onto chain-of- custody forms and placed in a chilled ice chest for delivery to a state-certified laboratory for analysis. Task 1.2 - Monitoring Well Construction: One monitoring well will be constructed using precleaned, threaded 2-inch diameter schedule 40 PVC well casing, screening the entire thickness of the aquifer, and a portion above the capillary fringe to allow observation for possible floating product. Final well design and placement will depend upon subsurface conditions encountered. The annulus between the casing and the borehole will be backfilled with 2/12 sand to about two feet above the screens. A bentonite clay spacer about two feet thick will beP laced above the sand pack, and cement grout will be pumped from above the bentonite to the surface using the tremie pipe. The traffic rated access vault box with locking device will cap the well. 'The new well will be developed to remove the drilling muck, grade the sand pack and provide a more complete hydraulic connection to the aquifer. The well volume will be calculated and a: number of those volumes will be removed until the water becomes clear and the amount of sand pumped is minimal. The well will be allowed to recover prior to sampling. A log of the development will kept for the well. The newly constructed well will be surveyed to known reference. e Svc; jcr.�w..�