CASTLE ROCK TRAVEL CENTER SITE, CASTLE ROCK, WA

A Level Two Hydrogeologic Assessment was conducted of a property on Old Pacific Highway, Castle Rock, WA. The assessment was to meet a Cowlitz County Ordinance for Critical Aquifer Recharge Areas to determine impact to the underlying aquifer for development of the property. The property is located adjacent to the North Fork Toutle River, in an area affected by mudflows that emanated from the eruption of Mt St Helens in 1980, and is underlain by alluvium and the Cowlitz Formation. The area of the property has historic coal mining activity and Mine Hazard was included in the assessment of area geologic, soil, and groundwater conditions. A final Level Two report for the property included a Proposed Groundwater Monitoring Plan prepared by Plateau, and an updated Spill Prevention, Control and Countermeasures Plan.