Site work for a bridge / tunnel in Maple Grove, Minnesota. Completed plans call for site work for a bridge / tunnel.

Site Address: 70th Place North, Vagabond Lane North, and 72nd Avenue North. The prequalification for tunneling will be used to create a list of prequalified contractors that will be allowed to perform the work of the tunneling portion of the Interceptor 900416 Replacement project. The project will include both tunneling and open trench installation and manhole installation for regional interceptor sewer. The project is located in Maple Grove, Minnesota, near 70th Place North, Vagabond Lane North, and 72nd Avenue North. The tunneling work includes installing approximately 2,100 lineal feet of 36-inch to 42-inch diameter steel pipe casing with individual tunnel run lengths ranging from 160 lineal feet to 390 lineal feet. Tunnel depths range from 25 feet to 45 lineal feet below the ground surface. The tunnels will be constructed under city streets, lawns, sidewalks, and trails. A 24-inch PVC carrier pipe will be installed inside the casings. The tunnel will be constructed in glacial till consisting of sandy lean clay, clayey sand, and lean clay and fill consisting of sandy lean clay and silty clayey sand. Blow counts ranging from 5 to 35 blows per foot. The groundwater level is expected to be below the casing invert. No cobbles and boulders were encountered in the soils, but they could be encountered in the tunnel. Tunneling method currently being considered, and for which qualifications are requested by this solicitation is pilot tube microtunneling with powered cutter head. To prequalify for this, the Contractor must submit 2 tunnel projects, using pilot tube microtunneling with powered cutter head or pilot tube guided auger boring or microtunneling. These terms are defined on the qualification form for each method. Respondents to this Invitation for Prequalification can submit PSDs for one, two, or all three tunneling methods. The tunneling portion of the Interceptor 900416 Replacement project will be completed by a contractor that is prequalified by the current process.