Bobtail Wall Excavation

The City of Black Hawk, Colorado is requesting bids on the Bobtail Wall Excavation project along Gregory Street, with bids due October 6, 2026 at 3:00 p.m. The scope comprises approximately 4,000 cubic yards of unclassified excavation with rock scaling, including tree and vegetation removal, demolition of existing timber crib walls, exposure of competent bedrock at a 1:3 slope ratio using conventional equipment only, scaling of loose and weathered material from the rock face and a 20-foot buffer area above it, and preparation of a 4-foot-deep by 8-foot-wide excavation at the toe of the slope for future retaining wall footing.

The project is located on the south side of Gregory Street in Black Hawk, Gilpin County. Work must occur between 7:00 a.m. and 7:00 p.m. daily. The contractor must provide traffic management flagging on Gregory Street, on-site sanitation facilities, and coordinate construction water procurement from the City's truck fill station at no cost. Staging is limited to the jobsite above the existing Gregory Street retaining wall and east of the Bobtail Mine building at 390 Gregory Street. A zero-cost Temporary Use Permit from the City is required for temporary facilities. No stormwater management plan or building permit is required due to anticipated disturbance under one acre.

The City will award the contract to the lowest responsive and responsible bidder. Unclassified excavation and scaling are paid on a unit-price basis for actual volumes hauled off-site; other items are lump-sum. Payment and performance bonds are not required. Bid security is not required. Bids must remain firm for 30 days from opening. Questions are due September 28, 2026. No formal pre-bid conference will be held; prospective bidders may visit the jobsite at their discretion. A final addendum will be issued on or before October 1, 2026. City Council action is scheduled for October 14, 2026, with construction completion on December 11, 2026. Contact Matt Reed, Project Manager, at (303) 582-2288 or mreed@cityofblackhawk.org.