Crane Flat Campground Soil Investigation for Wastewater Facilities

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The Crane Flat Campground, constructed in 1963, consists of five loops (Loop 100, 200, 300, 400, and 500) and five restroom facilities. Each restroom facility is isolated from each other and has its own septic tank and leach field.

• Loop 100 serves 23 campsites (building 6039)
• Loop 200/300 serves 35 and 16 campsites respectively (building 6040)
• Loop 400 serves 45 campsites (buildings 6041 and 6042)
• Loop 500 serves 36 campsites (building 6043)
Between 2012 and 2013, effluent was observed to have surfaced at the leach fields associated with buildings 6039, 6040, and 6042. Leach field repairs implemented in association with buildings 6039 and 6040 resulted in the successful rehabilitation of those leach fields thus bringing those restrooms back into operational service. Leach field repairs on building 6042 were unsuccessful and that restroom has never been put back online; currently portable restrooms are transported in to service that area of the campground.
As of 2015, the five Crane Flat Campground wastewater systems are 52 years in age. The overall objective is to provide rehabilitation and replacement improvements to these systems. However, at this time, this project is only requesting approval to:

• Drill 14 percolation holes, 6 inches in diameter, 5 feet below grade
• Drill 14 piezometer holes, 6 inches in diameter, 12 feet below grade
Percolation holes will likely be performed by mechanical hand-operated tools. Piezometer holes will utilize either a drill rig or a backhoe with an auger attachment. The percolation holes will provide an indication of the rate of effluent absorption of the native soil. The piezometers will allow the park to monitor and to track groundwater levels. This data is a necessary precursor to preliminary design. Compliance for design alternatives will be submitted through a future and separate project package.