By adding concrete liners and a foot-deep cap of compost, Napa’s city recycling center can become a better neighbor – and stay in line with tightening state environmental laws.
That is the goal of a major upgrade, approved Tuesday by the City Council, aimed at boosting Napa’s ability to keep more organic wastes out of landfills. The $10.4 million project will replace the open-air composting that has taken place since the 1990s at the Levitin Way center with concrete slabs and a top layer of mature compost, a combination meant to filter out odors and reduce stormwater runoff.
Air blowers and monitoring equipment would be added to manage the breakdown of organic materials, which usually takes about 45 days. The upgrade also will feature a redesigned drainpipe system directing stormwater into a single collection pond, where 1,000 gallons of runoff can be treated per minute, officials said.
Also helping to curb stormwater pollution will be a protective canopy over the composting area, which the city is building at a cost of $2.1 million.
Kevin Miller, Napa’s recycling manager, estimated the improvements will raise the plant’s composting capacity under its existing state permit from 40,000 to 66,640 tons per year. A fresh environmental study after work is completed may allow the city to process even more organic waste, as much as 105,000 tons annually, he told the council.
Richmond-based C. Overaa & Co. submitted the winning bid among three candidates, and is scheduled to complete the work around February 2019, Miller announced.
The composting overhaul is being approved amid Napa’s effort to step up the diversion of organic wastes, including food scraps and by-products, as a way to raise the diversion rate away from landfills from 65 to 75 percent by 2020.
Napa Recycling and Waste Services began a kitchen composting program in 2013 and expanded it to all customers two years later, allowing residents to mingle food wastes and biodegradable packaging with brown-bin materials such as yard waste and grass trimmings.