Final closure of Cummings Road Landfill slated for this summer
6/7/15
The Humboldt Waste Management Authority is putting a lid on the Cummings Road Landfill.
Some 15 years after taking over ownership of the property northeast of Eureka, HWMA’s contractor will begin work on Phase II to cap the landfill that once accepted solid waste from throughout the county. HWMA is a joint powers authority comprising the county of Humboldt and the cities of Arcata, Eureka, Ferndale, Blue Lake and Rio Dell.
Phase I of the landfill closure plan was completed late in the summer of 2012 at a cost of $4.4 million. Phase II, estimated to cost $2.28 million, begins in about a week with all work expected to be complete by Sept. 30. Both came with the North Coast Regional Water Quality Control Board’s approval of a Joint Technical Document for Closure, a document approved after years of information sharing and back-and-forth negotiation.
HWMA Executive Director Jill Duffy said the Phase II contractor, Meyers Earthwork of the Redding area, will have equipment on site by June 15. Their task is to install what Duffy described as “a burrito wrap,” an impermeable liner that will be attached to the site’s existing liner. The contractor also will create a haul road to transfer clean fill dirt, re-contour the land slightly, and cover the project area with 18 inches of clean fill dirt, Duffy said.
Getting to this point, Duffy said, was not exactly easy.
The Cummings Road Landfill opened in the early 1930s and was, for many years, a burn-and-shove operation. Garbage collected in and around the city of Eureka was transported to the site, burned and the remaining material pushed into surrounding ravines — a practice that continued until 1969, at which time the site became a cut-and-cover unlined facility. City Garbage took over management in 1974 and began accepting waste from throughout the North Coast. The facility stopped accepting solid waste in 1998.
Humboldt Waste Management Authority purchased the property in 2000, a move that came with the responsibility of permanently closing the landfill and an $8 million trust fund to accomplish that objective. City Garbage, which had since changed its name to NorCal Waste Inc, retained ownership of property surrounding the authority’s 33-acre landfill site. HWMA owns a total of 107 acres, including 1.23 acres of the burn dump area — where for decades what remained after the open-burning process was deposited.
Heavy storms in the winter of 2005-06 brought the residue of the burned refuse to the surface on property adjacent to the permitted landfill. In April 2013, the North Coast Regional Water Quality Control Board issued a Clean Up and Abatement order to HWMA and Recology-Humboldt to clean up the site in 18 months.
Previously, the Humboldt County Local Enforcement Agency determined in October 1999 that the site posed “no regulatory concern,” and no follow-up was required.
With the winter 2005-06 storms, the North Coast Regional Water Quality Control Board took a second look at the burn ash site. The burn ash covered 6.2 acres, and stretched across property owned by Recology Humboldt (formerly NorCal Waste, Inc) and Humboldt Waste Management Authority. What was originally thought to be some 58,000 cubic yards of burn ash, ended up to be 91,600 cubic yards.
“It was all pulled out and trucked to Phase II at the top of the landfill,” Duffy said. The ash was then covered with 6 inches of clean fill dirt with straw added for erosion control. The total project cost was about $3.5 million, but it could have been much higher. The ability to transfer the burn ash to the section of the landfill not yet capped, allowed HWMA and Recology to avoid some $12 million estimated to haul and dispose of the material elsewhere, Duffy said.
In some areas, she said, the burn ash was 20 feet deep.
“Much of the burn ash site was covered with dense (in some places impenetrable) brush and small trees with no drivable access,” according to a booklet Duffy put together to explain the process.
“This was a huge project,” she said.
By October 2014, the work was complete. As there was considerable land disturbance, Duffy said, HWMA will monitor vegetation and mitigate for erosion for a period of five years.
Humboldt Waste Management Authority then returned its focus to completing Phase II of the Cummings Roads Landfill closure. During the process, Geo-Logic Associates of Nevada City will provide Construction Quality Assurance Services, which includes a daily report to the North Coast Regional Water Quality Control Board. Once the existing liner and the new liner are attached, and the fill dirt covers the site, HWMA is still responsible for monitoring the site for 30 years following the closure with expected costs of $400,000 per year. Part of that expense comes in the operation of extraction wells that pump water out of the site into a storage tank. The contents will be transported to the city of Eureka’s wastewater treatment plant on a daily basis. The cost to haul and dispose of the leachate is $120,000 per year, Duffy said. Other expenses include monitoring, testing, and staff time to accomplish those tasks.
“The authority has been working for the last 16 years to close the landfill,” Duffy said. “There have been some pretty significant geologic and legacy sites challenges. We are really excited to be closing the landfill and moving into monitoring action. It reduces our liability pretty significantly.”
Duffy said she did not anticipate adverse impacts to Cummings Road neighbors. A water truck will be used to reduce dust, workers will be advised to drive carefully, and the equipment noise shouldn’t be disruptive, she said.
