H U Construction

Client:

U.S. Army Corps of Engineers

Scope Of Work

Wenck has been providing environmental support services directly to the U.S. Army since 2005, and indirectly through various Twin Cities Army Ammunition Plant (TCAAP) Operating Contractors or the U.S. Army Corps of Engineers since our inception in 1985. TCAAP was constructed in 1941, originally occupying four square miles and containing 323 buildings, and was used for the manufacture of small caliber ammunition from World War II through the Vietnam War. Contamination was discovered in 1981, with 18 soil sites and six groundwater plumes. The main groundwater plume extends nearly two miles, and affected the municipal water supply of two Minneapolis suburbs. TCAAP was designated as Minnesota’s #1 superfund site (the New Brighton/Arden Hills Superfund Site).

Wenck and Carl Bolander & Sons, an earthwork and demolition contractor, were retained as the team selected to perform a guaranteed price demolition and cleanup contract, involving the demolition of old manufacturing buildings from the 427-acre “plant” parcel, abatement of asbestos and other hazardous materials, underground steam lines (also asbestos-containing), sewer, water, natural gas lines, 300 overhead power poles, and six miles of railroad track. Under the contract with Ramsey County, who negotiated the purchase from the General Services Administration, remediation of soil must meet agency unrestricted land use screening criteria.

Wenck developed a Quality Assurance Project Plan (QAPP) employing Incremental Sampling Methodology (ISM), a technique developed by the Interstate Technology Regulatory Council (ITRC) in 2012. The ISM approach allows characterization of “decision units” using sampling techniques more representative of a typical risk exposure scenario, and gives a high degree in data results while simultaneously controlling laboratory costs. For a project site as large as the TCAAP facility, this approach has been extremely useful for both the regulators as well as the contractors working on the project. The $22.6M project spanned over 30 months.

By the year 2020, the site aims to be transformed into the Rice Creek Commons development – consisting of 159-acres of various commercial use, including office space and retail, a residential area including three new neighborhoods, as well as interwoven green space for recreation, stormwater management, and habitat restoration. “With 427 acres cleaned, revitalized, and brought back to the tax rolls, Rice Creek Commons will create significant economic and social opportunity for Ramsey County, Arden Hills, and the entire Twin Cities,” according to their website.