Description
The State of North Dakota’s Public Service Commission Abandoned Mine Lands Division seeks a qualified contractor to permanently close an abandoned underground coal‑mine portal near Cartwright, ND. The award will cover site investigation, engineering design, permitting support, construction of a permanent closure (including excavation, back‑filling, grout injection, grading, erosion control, and reclamation), and a two‑year warranty/maintenance period. The contractor must provide a detailed schedule, coordinate with State staff, submit monthly progress reports, and optionally offer mine‑void detection services.
• Perform geotechnical and hydrologic investigations, then develop full engineering design documents for a permanent closure solution.
• Execute construction activities – excavation, back‑filling, sealing with 3‑in. PVC pipe grout injection, grading, erosion control, topsoil replacement, seeding, mulching, and revegetation.
• Provide post‑construction documentation, as‑built drawings, final report, and a two‑year warranty to correct any settlement or structural deficiencies at no extra cost.