Mad River Geotechnical Investigation Project Lake or Streambed Alteration Agreement No. EPIMS HUM-68121-R1.

The Mad River Geotechnical Investigation Project, under Lake or Streambed Alteration Agreement No. EPIMS-HUM-68121-R1, involves basic data collection and resource evaluation within the Mad River watershed near Arcata, Humboldt County, California. The scope of work is limited to a single encroachment consisting of two geotechnical borings within the river channel. Key activities include trimming and limbing riparian vegetation, traversing the channel with a self-propelled track-mounted drill rig, and utilizing augers and mud rotary drilling to create two boreholes up to 8 inches in diameter with depths ranging from 50 to 60 feet. Following the drilling process, the boreholes must be backfilled with native materials to the maximum extent feasible. The project is managed by the California Department of Fish and Wildlife and is designated as a Categorical Exemption under CEQA Class 6, as it is determined that the activities will not result in significant environmental impact. The specific site of performance is located near 5115 Boyd Road in Arcata, identified by Assessor Parcel Number 507-261-004 and coordinates 40.9119 N, 124.0713 W. Administrative oversight is provided by Michael van Hattem, Senior Environmental Scientist Supervisor, and Patrick Kaspari.