MITCHELL ENGINEERING provides emergency repair services to both Public Agencies and Private Owners faced with consequential damages or potentially damaging conditions that may cause immediate or near term danger to life, health, property, or the environment. The below sample Projects exemplify the capabilities of MITCHELL ENGINEERING.
Helms — Penstock Tunnel Plug and Shear Zone Rehabilitation
(near) Shaver Lake, California
Project consisted of critical repairs to rehabilitate the bypass tunnel’s concrete plug and mitigate the impact of leakage into the Helms Pumped Storage Powerhouse Complex. Scope of work included drilling 120 holes (totaling 3,980 lineal feet) and installing high pressure grout using the Grouting Intensity Number (GIN) method; sealing of weep holes and cracks in the Penstock Access Tunnel; drilling and re-grouting of existing grout holes in the concrete tunnel plug; drilling and installing new piezometers and horizontal drain holes; and the chemical grouting of weep holes in the main penstock tunnel. Owner: Pacific Gas & Electric (PG&E) Contract Amount: $4.5 million
El Dorado County, California
The work to be consists in general of cleaning away remaining slipout debris, installing a soldier pile tieback retaining wall, constructing an engineered fill above the soldier pile retaining wall, constructing a concrete retaining wall, installing metal beam guard rail, and performing drainage and roadway repair work. Owner: County of El Dorado, State of California Contract Amount: $2.2 million