Description
The National Park Service is seeking a contractor to repair a short, erosion‑affected segment of Conzelman Road within the Golden Gate National Recreation Area. The work includes drilling six 30‑in. cast‑in‑place piles, constructing a 51‑ft reinforced retaining wall, installing a California ST‑75 bridge rail, rebuilding the pavement with a 13‑in. aggregate base and HMA Type A, and providing full road closure and detour signage for up to 180 days. The contract is set‑aside for HUBZone small businesses and will be awarded on a lump‑sum basis.
• Drilled cast‑in‑place piles (30 in. diameter, ≥ 28 ft total length) into hard sandstone/shale/chert.
• Construction of a reinforced retaining wall with epoxy‑coated reinforcement and waterproofing/drainage system.
• Installation of California ST‑75 bridge rail, guard‑rail replacement, and full pavement reconstruction to match existing conditions.
• Full road closure for up to 180 days, with required detour signage and compliance with seasonal vegetation and nesting‑season restrictions.