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Asphalt Paving Co. <br />April 1, 2015 <br />Page 2of2 <br />Localized ponding and springtime snowmelt accumulating on the upper benches is the likely <br />cause of the flowing conditions observed in boring BA -3 and monitoring well BA -4. <br />Boring BA -5 was dry when measured; the measurement depth limited to 100 ft due to length of <br />water level reader. The dry conditions observed in boring BA -5 are likely the result of borings <br />proximity to an adjacent lower lying pond and draining through the near - surface fractures in the <br />basalt. <br />Conclusion <br />No in -situ groundwater was observed by Brierley at the Ralston Quarry during drilling. Brierley <br />field staff did monitor the levels of drilling fluids and boreholes flushed with fresh water after <br />drilling; the small degree of fluctuation (in conjunction with the packer test results) demonstrates <br />that the rock formations within the quarry have low permeability. Additionally, the flowrates of <br />water observed seeping out at the ground surface at two boreholes increased during rain and <br />snowmelt indicating the source of this phenomenon was driven by accumulation of precipitation <br />on the flat benches at higher elevations nearby those two borings. <br />We appreciate the opportunity to work with you on this project. If we can be of further <br />assistance, or if you have any questions, please contact our office. <br />Sincerely, <br />BRIERLEY ASSOCIATES <br />y <br />A cca <br />Associat( <br />Attachments: Figure 1 — Boring Location Map <br />Steve Kuehr, P <br />Principal <br />BRIERLEY <br />ASSOCIATES <br />Creating Space Underground <br />