Harmon Tunnel Highwall (Bluff) Scaling, Pammel State Park, Madison County

The Iowa Department of Natural Resources is requesting bids on rock scaling and debris removal at the Harmon Tunnel Highwall in Pammel State Park, Madison County, with bids due June 25, 2026 at 3:00 p.m. This is a qualification-gated procurement: all rock slope scaling foremen and personnel must have performed satisfactory work on three similar projects within the last five years and possess a minimum of two years of full-time experience in rock slope stabilization including rock scaling.

The scope is removal of loose, unstable, disjointed, spalled, and exfoliated bedrock fragments and talus from both northeast and southwest tunnel portal highwalls using manual, mechanical, or chemical non-explosive methods only—blasting is prohibited. Work includes disposal of all resulting spoil and loose material located between the zone of influence and tunnel pavement. Contractors must submit a detailed work plan at least ten working days prior to beginning operations. The tunnel will remain closed to traffic during construction. Contractors bear full responsibility for equipment, materials, labor, traffic control, personnel and public protection, damage prevention to historic tunnel elements including stacked stone retaining walls and tunnel arches, environmental protection, and emergency management.

Bids are structured as lump-sum pricing for three items: mobilization, scaling operations (defined as one qualified foreman and minimum two qualified scalers), and scaled material disposal. Contract completion is required by November 30, 2026, with liquidated damages of $1,000 per calendar day for work remaining incomplete. If the contract price equals or exceeds $25,000, a performance bond equal to one hundred percent of the contract price is required with a surety authorized to do business in Iowa. The contractor must obtain an NPDES Stormwater Discharge Permit (DNR's General Permit No. 2) prior to commencing work. Public liability and property damage insurance with minimum coverage of $250,000 per person and per occurrence and $500,000 aggregate is required. Bids must be submitted electronically to constructionbids@dnr.iowa.gov.