An expert panel Monday urged Bristol, Virginia to “strongly consider” ceasing landfill operations as part of a detailed series of recommendations regarding its embattled landfill.
The 11-member panel was assembled last month to study issues with the city’s 137-acre quarry landfill and offer suggestions on how to remedy widespread odor and emission issues. A 40-page report was issued Monday outlining proposed steps.
The panel was assembled by Virginia Department of Environmental Quality Director Michael Rolband at the urging of state lawmakers and coordinated through the Virginia Tech School of Engineering.
The report includes 10 specific findings regarding the landfill’s current state and 10 proposed action steps to address odor mitigation. Finally, the panel considered scenarios for how the city could continue operating the landfill, or reasons to close it.
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No cost estimates were associated with any of the recommendations.
The report recommended engineered actions intended to “minimize the release of odors, reduce landfill temperatures, and manage problematic conditions beneath the landfill.” This strategy includes preventing infiltration of precipitation and control and management of stormwater inside the landfill.
In its conclusions, the report also delves into potentially closing the facility.
“The city should strongly consider a cessation of waste disposal operations at the landfill due to incompatibility of operations with the necessary odor mitigation and ETLF [elevated temperature landfill] remedial strategy,” according to the report.
City consultants had previously warned that trying to close the quarry landfill without building up the amount of waste included in its operating plan – more than another 20 years’ worth – wasn’t practical and could lead to additional problems.
“Consensus was that landfill odors are the result of a reaction taking place beneath the landfill surface within the buried waste. The chimneys along the landfill perimeter are likely the major avenue for release of these odors into the atmosphere,” according to the report. “The presence of the chimneys suggests that the subsurface sidewall liner system has failed locally and the resulting poor contact between the landfill liner and quarry sidewalls hinders containment of high-temperature landfill gases.”
The panel agreed engineered remedial action can significantly reduce the release of odors around the landfill perimeter, but regulatory approvals are needed to implement the proposed remedial approach involving any changes to the liner configuration.
The panel further concluded there is insufficient data to determine the degree to which odorous gas are seeping through the landfill interim cover material into the atmosphere.
The panel also concluded benzene, which is seeping into the landfill’s wastewater discharge, is “not believed to be derived from an external source of contamination based on currently available data. Benzene is likely being derived from the waste mass, but the mechanism of production or release is unknown due to insufficient data,” according to the report.
While the report does not classify the site as an “elevated temperature landfill,” the experts wrote that it does have similar traits.
“The panel consensus was the landfill is exhibiting early signs of an elevated temperature landfill (ETLF) which is linked to production and release of odors. ETLFs are primarily characterized by temperatures in excess of 55°C (131°F) over a broad area for a sustained period of time and an atypical accumulation of heat,” the report says.
“ETLFs are characterized by low methane content in the landfill gas, high leachate production rates, leachate with elevated concentrations of organic compounds, production of odoriferous gas, rapid settlement, and self-propagating reactions that generate heat. This condition has the potential to worsen unless prompt (immediate) action is taken.”
The panel recommends the following actions to address odor and emission issues:
» Test and construct a sidewall odor mitigation system around the landfill perimeter that will be designed and constructed to mitigate landfill gases emanating from the landfill/quarry sidewalls.
» Improve the performance of existing gas extraction wells, including minimizing air intrusion pathways through landfill cover. Additional gas extraction wells will be needed to reduce emissions and temperatures.
» Identify and eliminate to the extent practical any landfill gas fugitive emissions at the landfill surface. Weekly monitoring activities of gas emissions at the landfill surface will be required.
» Install settlement plates and conduct monthly surveys to document the locations and rates of settlement in the waste mass.
» Install and monitor a dedicated system of thermocouples in the waste mass to monitor landfill temperatures for greater spatial resolution (horizontal and vertical) and to provide data at a greater frequency.
» Install at least five deep dedicated monitoring wells to enable sampling and characterization of leachate and measurement of temperature profiles in the waste.
» Install and operate large-diameter dual-phase extraction wells for removal of gas and leachate. Treatment requirements for extracted leachate must be determined.
» Install a temporary geosynthetic cover over the entire landfill. This will require substantial grading of the existing landfill surface to direct runoff to the southeast corner of the landfill, where it is expected a stormwater management pond can be constructed to manage stormwater that is collected on top of the geomembrane cover.
» Develop and implement an effective and sustainable stormwater management plan and settlement management plan for the landfill.
» Create an active community outreach program to communicate strategies, provide status and progress reports and receive citizen feedback.
However, the panel also cited additional concerns.
“Continuing landfill operations while implementing the proposed remedial actions is problematic. Limiting operations to the northern end of the landfill while addressing the ETLF condition in the southern area of the landfill is not recommended,” according to the report.
Among its closure deliberations, the panel considered options for early closure including the “feasibility of (1) installation of a permanent landfill cap at the current waste level following mitigation of odors and reduction of landfill temperatures; and (2) rapid fill of waste to the quarry rim followed by installation of permanent landfill cap.
“Installing a permanent landfill cap designed to accommodate expected waste mass settlement without additional disposal of waste (other than shaping the landfill surface) once odors and landfill temperatures are adequately reduced is a feasible option,” according to the report. “Rapid fill of the remaining permitted air space in the landfill followed by a permanent landfill cap is not recommended given concerns for the ETLF considerations and cost considerations.
“Resuming operations at the landfill in the future may be technically feasible once the odors are controlled and ETLF conditions managed. However, there may be other technical, cost, and political considerations that would inform such a decision,” the report concludes.
Rolband, in a written statement, called the report “crucial.”
“We appreciate all the hard work and dedication of the panel members and the city to focus on these important issues and develop this detailed report of recommendations on time,” Rolband said in the statement. “The report, the result of the panel’s careful and thoughtful collaboration, will be crucial to helping the city of Bristol implement practical solutions for these issues going forward.”
City Manager Randy Eads said Monday he had just received a copy of the report.
“The city appreciates DEQ’s willingness to step in and provide a panel of experts to review our landfill and the odor situation. Obviously, the report has just been released, and I have not had an opportunity to review the report in depth. Over the next several days, I will review the report with the city’s consultants, council and DEQ and begin taking the appropriate steps to follow the recommendations of the experts,” Eads said.
State Sen. Todd Pillion, R-Abingdon, expressed his appreciation.
“Our priority has been and remains getting the best relief for the residents of Bristol in the best way possible. That means getting the best information from experts and regulators who understand the complexity of the situation with the Bristol landfill,” Pillion said. “I commend this expert panel for spending multiple days in Bristol visiting the landfill, smelling what Bristolians smell and working collectively to develop these findings and offer recommendations to the city of Bristol.”
Pillion said the report can be a guide and expects the state to assist with funding.
“During the 2022 General Assembly session, we introduced Senate and House budget amendments authorizing the Department of Environmental Quality to provide emergency technical assistance to the city of Bristol, Virginia in resolving ongoing issues with the city-owned landfill and to facilitate a long-term plan for the operational status of the landfill,” Pillion said. “The findings by this expert panel provide important guidance and direction for the city's consideration in determining how to proceed. We continue standing ready to facilitate state-level support for a solution to this matter.”
Del. Israel O'Quinn, R-Bristol, also praised the quick response by the expert panel.
“Senator Pillion and I began formalizing DEQ’s advisory role during the legislative session and this is an important step in that process. I am thankful for DEQ Director Rolband’s attentiveness and responsiveness to the issues at the city-owned landfill and the work done by the expert panel can have a positive impact for our community," O'Quinn said. "The panel’s report provides a solid framework going forward, and there are real fixes and measures to implement to help everyone in Bristol. Our legislative delegation stands ready to assist DEQ and the city however we can.”