A Comparison of Horizontal Hydraulic Conductivity Values Derived from Aquifer Test and Well Specific-Capacity Data for the Sequim-Dungeness Area

Transmissivity results from eight aquifer tests were used to derive horizontal hydraulic conductivity values for hydrogeologic units underlying the Sequim-Dungeness Peninsula in Clallam County. Specific-capacity information for the tested production wells also was analyzed to obtain a second hydraulic conductivity value for comparison against the "aquifer test" results. These paired estimates differed by less than a factor of 2, which is comparable to the "internal" variability in hydraulic conductivity noted for the individual aquifer tests. This evaluation suggests that, for the Sequim-Dungeness area, well specific-capacity data provide comparable hydraulic conductivity values to those values estimated through more intensive aquifer testing methods. A D e p a r t m e n t o f E c o l o g y R e p o r t