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Wright has consulted drilling contractors who have previously worked at the site. The subsurface area of investigation is known to have severe flowing conditions at depth. Flowing conditions create great difficulty when drilling with hollow stem augers. Severe flowing conditions cause sediment to effectively liquefy locally at the borehole and make monitoring well completion very difficult and affect overall construction and well performance. For these reasons, Wright proposes to use mud rotary drilling for all well installations to address this subsurface problem. Mud rotary drilling will stabilize the borehole walls sealing them to prevent both cross contamination and borehole wall collapse. These two-inch diameter wells placed to 60 feet will be drilled to their completion depth(estimated to be no deeper than 65 feet) and completed. The well installation to 114-119 feet will require placing a conductor casing to 65 feet to seal out the higher contaminant zones. The conductor will be drilled into place using mud rotary. Following bailing out the drilling muck and a seal leak check, the borehole will be advanced to the well completion depth (estimated to be about 115 feet) and the well constructed. Due to the depth of this well completion, Wright will install a four-inch diameter well casing. Field Methods -Exploratory Borings USA Clearance and Access Agreements or Encroachment Permit Access Wright will install these wells under approved well installation permits from PHS EHD. An underground service alert (USA) call will be made to clear underground utilities prior to drilling. Aerial utilities are present on either side of East Charter Way, so boreholes will have to be adjusted to accessible locations. At least two monitoring wells are to be placed off-site so access agreements or public encroachment permits will have to be secured prior to drilling those locations. Wright will contact the adjacent property owners to ascertain access requirements and will move to secure encroachment permits at the same time so some flexibility for drilling exists. However, the length of time to secure privately owned access is unknown at this time. Wright and PHS EHD will need to work together informing property owners of importance of allowing this work to proceed without unreasonable demands for access by off site property owners. Decontamination The drilling rig and rods, samplers and cables will be decontaminated prior to arriving at the site, between each borehole and prior to leaving the site. The equipment will be washed with pressure washers and soapy water and sampler gear will be hand washed in soapy water using a triphosphate soap. The decontamination water will be stored in closed top drums and temporarily stored on-site. Page 4 of 4