Project Overview
NTH was retained by a natural-gas utility client, Consumer’s Energy, to provide construction quality assurance (CQA) for the installation of secondary containment areas at processing facilities for storage fields located throughout Michigan. The containment areas included geosynthetics installation consisting of both single-layer and double-layer containment systems. NTH provided CQA services during the geosynthetics installation to observe conformance with project specifications and industry standards. NTH also provided certified weekly construction stormwater inspections in accordance with your SESC permit, and construction materials testing services.
Project Scope
Consumer’s storage field processing areas require the installation of secondary containment systems to meet environmental regulations. Design for secondary containment typically includes a single 60-mil HDPE textured geomembrane installed around a concrete tank pad and secured with an anchor trench around the outside perimeter of the containment berm or containment wall. NTH worked closely with Consumer’s Energy, geosynthetics installation contractors, and earthwork contractors to document the installation of the geosynthetic containment areas met the project specifications and industry standards.
Construction activities included installation of HDPE primary and secondary geomembrane liner systems and geonet leak detection/drainage systems for some components of the processing area. NTH was contracted to provide construction quality assurance which included assembling and auditing manufacturer’s submittals and verifying geosynthetic materials and quality control data.
Additionally, NTH observed the installation of secondary and primary geosynthetic membrane liners for compliance with project specifications. NTH observed seaming operations, destructive and nondestructive sampling and testing in addition to the installation of the geonet leak detection/ leak detection drainage system. Our historical involvement with similar projects and thorough client understanding, as well as understanding of regulatory requirements, helped us complete our tasks within deadlines and budget constraints, while maintaining high quality construction standards that Consumers Energy expects.
NTH has performed CQA services of secondary containment for various natural gas facilities. NTH also recently assisted in performing construction materials testing and certified SESC stormwater inspections at the OVS Salem Scrubber Brine Tank Replacement project.
Client Benefit
NTH worked closely with Consumers Energy and the geosynthetic installation contractor to review the technical specifications of the project. NTH presented the client with a solution to resolve the issue by installing an additional inspection well to be able to monitor liquids that may be collected in the area. NTH’s involvement in completing CQA services for the secondary containment installations provides Consumers Energy independent verification that the installation met regulatory and industry standards, avoiding compliance issues that may arise in the future with regards to the secondary containment installation.
