STGE - GTT Retaining Wall Rehab

The National Park Service Midwest Region seeks quotations for rehabilitation of a historic limestone retaining wall at Sainte Genevieve National Historical Park in Missouri, with quotes due July 20 at 9:00 AM Central Time. This is a total small business set-aside, NAICS code 238190, with an estimated project magnitude between $100,000 and $250,000 on a firm fixed-price basis.

Place of performance is 99 S Main St, Ste. Genevieve, Missouri 63670. The scope involves hand deconstruction, labeling, cleaning, and reconstruction of approximately 90 linear feet of historic mortared limestone retaining wall, 4 feet high and 1.5 feet thick, built in 1803. Work must use NHL 3.5 lime mortar (1-part lime to 2.5-part sand per ASTM C270 Type N), hand tools only (no mechanical excavation), and achieve completion within 180 calendar days from Notice to Proceed (performance period August 15, 2026 to February 11, 2027). Recent Amendment 0002 (July 8) permits replacement of up to 15 percent of stones if existing stones are unusable, subject to Contracting Officer approval, and requires over-excavation of 6 to 8 inches with non-woven geotextile fabric and 6-inch minimum limestone bearing layer. Work is restricted to 8 a.m. to 4 p.m. Monday through Friday, with a 70 dB(A) noise limit and comprehensive photo documentation required. An archaeologist from the Midwest Archeological Center will monitor ground disturbance. Quotations must be submitted via email as a single PDF not exceeding 25 MB. Bonding varies: quotes below $150,000 require Payment Bond or Irrevocable Letter of Credit (100% of contract value) within 10 days of award; quotes $150,000 or above require Performance and Payment Bonds (100% of contract value) plus Bid Bond (20%, not to exceed $3 million) at quote submission. Prevailing wage determination MO20260001 applies. Award will be made to the offeror providing best value considering price, technical capability, and prior experience. Contact: Bridget Parizek, bridget_parizek@ios.doi.gov. Offerors must acknowledge receipt of Amendment 0002 by the July 20 deadline.