Underground Storage Tank Replacement at the Center Street Bus Maintenance Facility

American Recovery and Reinvestment Act (ARRA) funding allowed TriMet to replace aging underground storage tanks at the Center Street bus maintenance facility. Six single-walled storage tanks were replaced with four double-walled tanks with improved leak detection safeguards.

The new underground storage tanks each hold 2500 gallons of fluid—one replacement tank dispenses fluids and the remaining three collect and store used oil and other fluids for off-site recycling. The space between the two walls of each tank is filled with brine. Sensors monitor the level of the liquid between the two walls and activate a warning if the brine level changes, indicating that the tank may have a leak.

The Center Street bus maintenance facility supports the highest number of buses in the region, with approximately 280 buses serviced at this location every day. 300-350 gallons of used fluid are gathered daily from TriMet vehicles at this facility.

Additionally, four new 20,000 gallon diesel tanks are being installed at the Merlo Garage as part of the ARRA-funded Merlo Fuel/Wash and LIFT Building project. Over the past several years, TriMet has also replaced diesel and critical fluids tanks at the Powell and Center garages, upgrading them from single-walled to double-walled tanks.

Job retention

The contractor for the Center Street tank installation was Anderson Environmental Consulting. Subcontractors included Boyles Electric, NW Pump, Hines Trucking and Sawcutters/Saw Cutters NW. Hines Trucking and Sawcutters/Saw Cutters NW are both part of TriMet’s Disadvantaged Business Enterprise program.

$435,000 in ARRA funds supported 10 jobs and retained three others among the contractors working on this project.