Weston performed time sensitive construction of temporary access roads on the upstream and downstream embankment slopes at Hills Creek Dam, OR so that USACE could conduct geotechnical assessments to understand conditions within the dam embankment and foundation to evaluate risks and determine the degree of urgency for action if required.
Weston developed a Work Plan, Quality Control Plan, Benching Plan, and Safety Plan and mobilized personnel and equipment ahead of schedule within 2 weeks of contract award to meet the aggressive schedule for the USACE crew to drill deep soil borings. Weston self-performed construction of the upstream slope access road by carefully removing and repositioning riprap, performing rough grading and placing surfacing rock on the steep, 2:1 horizontal/vertical slope to build the 12.5 ft wide and 1,400 ft long access road. A similar access road was also constructed on the downstream face. Weston personnel also excavated test pits and an infiltration pit to facilitate the geotechnical investigations, and restored the site to pre-construction conditions after geotechnical studies were completed.
The access roads provided temporary but critical infrastructure to provide a stable work platform for the drill rig and support vehicles. Site access and staging was coordinated with Dam Operations personnel to avoid impacts to dam operations personnel during the work. The field work to provide the needed access was completed in less than 2 weeks by simultaneous construction of the upstream and downstream access roads, which was critical to maintain schedule for the geotechnical work performed by the USACE Savannah District.
