Geomembrane Gas Mitigation Wall Design

I need a complete engineering package for a subsurface vertical barrier wall that will stop lateral migration of landfill gas beneath a site underlain by uncontrolled fill. The design must rely on a continuous geomembrane sheet system rather than concrete or steel, and every calculation, drawing, and specification has to focus on gas mitigation performance. Scope of work • Develop wall alignment, depth, and tie-in details based on the uncontrolled fill profile and anticipated gas flow paths. • Produce design calculations demonstrating impermeability, interface friction, long-term durability, and global stability. • Prepare construction drawings (DWG and PDF) including trench geometry, panel overlaps, anchor trench, venting points, and connection to existing structures. • Write a Construction Quality Assurance Plan (CQAP) that spells out material testing, panel integrity checks, seam air-pressure testing, frequency of inspections, and acceptance criteria for both installation crew and third-party inspectors. • Summarize maintenance and monitoring recommendations once the wall is in service. Acceptance criteria 1. Gas transmissivity across the wall ≤ 1 × 10⁻⁸ m²/s as proven in design calc sheet. 2. CQAP aligns with ASTM D6707, D5887, and EPA Subtitle D guidance. 3. All drawings are provided in both CAD (AutoCAD 2020 or later) and printable PDF formats. 4. Final report, drawings, and CQAP are internally cross-referenced and ready for regulatory submission. If you have direct experience designing geomembrane cutoff walls for gas mitigation and can deliver the full package on schedule, I’m ready to move forward quickly.

Project ID: 40227419