The Board of Estimates is expected to approve tomorrow additional cost overruns at one of the biggest infrastructure projects underway in the Baltimore region – an Enhanced Nutrient Removal facility at the Back River Wastewater Treatment Plant.
The new pumping station, designed to reduce the amount of nitrogen and phosphorus dumped into the Chesapeake Bay, was originally bid at $265 million by Archer Western Contractors two years ago.
The latest overruns of $10.4 million – combined with $5 million in earlier overruns – will add 6% to the cost of the project.
The work is now two-thirds complete and is expected to be finished in November 2016, Jeffrey Raymond, chief spokesman for the Department of Public Works, said today.
The project is part of the state’s Chesapeake Bay Restoration Program that aims to reduce the nitrogen in sewage flushed by regional households that contribute to algae blooms in the Bay that lower the oxygen content in the water and cause fish kills.
Under the improvements, nitrogen levels are expected to be cut by 90% in the wastewater released into Back River and the Bay. Chemical treatment at the plant already has reduced a large portion of phosphorus, which will be further cut by the new facility.
The cost overruns will pay for twice moving contaminated soils excavated at the site.
Originally, the soils were to be placed in an unnamed “residential landfill,” but the Maryland Department of the Environment (MDE) ruled that the soils’ chromium levels were too high for safe dumping.
“To prevent delays to the project’s schedule,” the contaminated soils were hauled to temporary stockpiles at the sewer plant, then deposited at the Norris Farms Landfill, a former Browning-Ferris hazardous waste site off North Point Boulevard near Dundalk.
DPW’s design consultant, Whitman, Requardt & Associates, did not detect the high levels of chromium in the soils, according to a board summary of the cost overruns.
Even so, the consultant was tasked by DPW to review the price proposed by the contractor to dispose of the soils at Norris Farms.
After the price “was found to be acceptable” by Whitman Requardt, an “EWO” (extra work order) was prepared by DPW and forwarded to the spending board.
The project is chiefly underwritten by the State of Maryland. The state will reimburse Baltimore about 94% of the cost of the latest EWO, Raymond said.