Foresta Crane Creek Bridge Geotechnical Borings

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In order to determine the depth of bedrock in the location where proposed new bridge abutments would be constructed for a replacement bridge, two geotechnical borings will be required on either side of the existing Crane Creek Bridge in Foresta. Geotechnical work will be performed by Kleinfelder in late October/early November. Drilling equipment will only be operated between 8:00a.m. and 5:00p.m. for two non-weekend days, with scheduled disruptions during the day to allow for traffic. The replacement bridge's abutments will be located outside of the ordinary high-water mark and within the existing area of disturbed roadbed.

Borings will be 8 inches in diameter and 20 feet deep. Boring equipment will require water to be flushed into boring holes which will be drawn from Crane Creek, and returned to the creek with negligible amounts of turbidity. Water returned to the creek will gently flow through a vegetated area prior to entering the creek. It is estimated that between 50 to 100 gallons of water would be required for each boring, for a total of no more than 200 gallons of water to be used.

Cuttings (i.e., rock and soil) will be stockpiled in a contained location on site and will be removed upon completion of boring activity. Staging area for equipment storage for one night will likely be located at the Fire House (preferred, and upon approval) or in the parking area between the intersection of Old Coulterville Road and Foresta Road traffic delays are expected for up to two days during exploratory boring activities.

Because Foresta Road is one lane, and the drilling equipment must be placed in the location the borings are occurring, through traffic will not be permitted during boring activities - with the exception of emergency vehicles. However, through traffic will be permitted for scheduled periods of time each morning, afternoon, and evening - with closures during periods in between.

Equipment would be brought into the park from an out of park location. Equipment will be cleaned and inspected prior to entering the park to ensure no soil, seeds, or other organic materials having the potential to bring non-native species or noxious weeds into the park.