Maca-replace and expand sand cave trail

The National Park Service Southeast Region seeks sealed bids to replace and expand the Sand Cave Trail at Mammoth Cave National Park in Kentucky, with proposals due August 18, 2026 at 3:00 PM CST. The procurement is a total small business set-aside and is firm-fixed-price with award on a lowest-price-technically-acceptable basis.

Place of performance is the Sand Cave Trail head at Mammoth Cave National Park on Old Mammoth Cave Road. The project includes three line items: mobilization and demobilization (CLIN 00010), reconstruction of the Sand Cave Boardwalk with demolition and installation of concrete trails, boardwalks, composite decking, and overlooks (CLIN 00020), and an option item for a secondary Sand Cave Trail with timber steps, aggregate trail, metal stairs, and viewing deck (CLIN 00030), with an anticipated option exercise date of 60 days. The contractor must commence work within 10 calendar days of receiving notice to proceed and complete all work within 180 calendar days. Period of performance is August 31, 2026 through March 1, 2027.

The contractor must comply with prevailing wage rates per Wage Rate Determination KY20260040, provide performance and payment bonds within 15 calendar days of award, and maintain liability insurance with minimum coverage of $1,000,000 per person and $2,000,000 per occurrence for bodily injury, plus $2,000,000 property damage. Work must be performed during 8:00 AM to 5:00 PM, Monday through Friday, unless approved otherwise. The contractor is responsible for all permits, including KPDES permits, and must source non-potable construction water from outside the park boundary. Archaeological protection requires air-filled tires on all off-road equipment; tracked equipment requires pre-approval. Landscape restoration includes seeding, topsoil, and soil amendments based on soil testing. Technical acceptability requires two completed projects within the last five years involving boardwalk, trail, or exterior site construction with demolition and new accessible walkways in park or public-use settings adjacent to sensitive natural or cultural resources. Electronic invoicing through the Invoice Processing Platform is mandatory. Amendment 0002, posted August 11, extended the proposal due date to August 18 and incorporated government responses to contractor questions and a site-visit sign-in sheet as required attachments.