The Obrist Landfill accepted construction and demolition debris until the late-1980's. After filling was completed, a soil cap was placed over the 16-acre disposal area and Sunrise Park was developed by the City of Troutdale. GFA prepared the closure/post-closure plan for the landfill and assisted in the design and construction of park facilities.

The primary feature of the park is a geosynthetically-lined pond which provides detention for surface water run-off and a wildlife habitat for migratory birds. The pond which is located over 80-feet of refuse includes a secondary containment system for leak detection. Ditches and the landfill's final grades were upgraded to meet DEQ requirements. Over 2500-feet of pedestrian walkways were paved with recycled asphalt.

Development of single-family residences around the landfill has encroached to within 30-feet. A system for monitoring landfill gas migration was established and includes 21 landfill gas probes located around the landfill's perimeter. In order to conserve City funds, GFA developed an environmental monitoring plan that can be implemented by City personnel and trained City staff in its performance.