Jan. 14, 2026
VIROQUA, Wis. — The Viroqua Common Council and the Viroqua Public Works Committee met on Jan. 13 to address critical environmental concerns at the city’s closed municipal landfill. The site was originally a town dump that lacked modern liners and was closed in the early 1990s as state regulations became more stringent. High levels of methane gas were detected in March 2025 during utility work near Sands Road, leading to a notice of non compliance from the Wisconsin Department of Natural Resources. Recent data indicates that the original passive vents are non-functional, allowing gas to travel through porous sand layers toward adjacent properties. In other words the site was venting out, instead of up. That is what triggered the DNR to require actions to remediate the issue.
The site is located in the northwest part of the city. The site was originally all one area but has since been bisected when Chicago Avenue was extended as a bypass for the Main Street construction in the late 1990s. The end result was one section is located at end of Sands Road and the other section of west of that area on the other side of Chicago Avenue.
Summary of mitigation steps taken to date
Remediation efforts began shortly after the detection of gas in March 2025 with the city hiring Mike Amstad with TRC as consultants. In early meetings Amstad said he would need more investigation and would start with the least expensive “passive” approaches. Amstad said if those efforts proved ineffective an active blower system might be required. That city appears to be at that point now.
Initial steps included drilling seven gas probes to monitor migration and digging an L shaped trench on the east side to intercept gas moving toward a nearby church. During this excavation, contractors discovered waste materials outside the originally mapped landfill boundaries, indicating the problem was more extensive than previously recorded. A temporary blower system was installed near the church to pull a vacuum and keep gas levels below the explosive limit of 5%. Throughout the fall and early winter, crews worked in freezing conditions to install an additional 15 gas probes to achieve full monitoring coverage around both the east and west sections of the site.
You can read our previous stories about those efforts here.
Migration data and technical updates
At the meetings of Jan. 13, Amstad gave the city an update in the current status of their effort and recommendations on paths forward to mitigate the issue. He explained the situation to the Public Works Committee and later to the full City Council.
Amstadt explained that gas levels around the east section have remained high despite initial remediation efforts. Crews have been installing more monitors around all sides of both sections of the site.
“Based on the readings, you can see we have basically all the way around the East landfill,” said Amstadt. “It is not consistently greater than 20% but it is persistent.”
Amstadt noted that while a temporary blower system currently protects a nearby church, the gas has no other choice but to follow the path of least resistance through the soil.
“The sand underneath the landfill and the surrounding area is a very, very clean fine sand,” said Amstadt. “We have basically gas built up in the two landfills to the point that it is migrating.”
City Engineer Sarah Grainger emphasized that the DNR is demanding a complete understanding of how far the gas has traveled beyond the property lines.
“Most recently, they said the code requires that we know the full extent of the situation and migration of the gas,” said Grainger. “They made it very clear that we also need to be looking at the west side.”
Active system and future strategy
Amstadt recommended that the city transition from passive venting to an active system that uses mechanical blowers to create negative pressure within the waste mass.
“The active system is basically either purchasing one blower to put a vacuum on both landfills or two smaller blowers,” said Amstadt. “We’ll draw a vacuum create a negative pressure on the landfill that’ll pull the gas towards the vertical wells and keep it from migrating off site.”.
He explained that the current system is insufficient because there are too many gaps in the current infrastructure to prevent gas from leaving the city property.
“I think there are too many holes and there is still the possibility that you will get migration,” said Amstadt. “We may need to go to an active system where we are actually pulling a very strong vacuum on the landfill.”
Amstad said he will put together numbers on the cost of various options for an active mitigation system and brings those back to the city for consideration. Those systems could include one large blower for both areas or two separate smaller blowers. And an option for another passive approach that would involve drilling numerous holes to encourage venting on both areas.
Consideration of waste removal
The committee discussed the possibility of excavating the entire site to remove the waste, but Amstadt warned that this would likely create more problems than it would solve.
“Problem is the problem does not go away,” said Amstadt. “The DNR will have you test the bottom of the soil to confirm that you have excavated all the way down to clean soil.”.
He pointed out that digging into the site could expose the city to long term liabilities regarding groundwater contamination that are currently dormant.
“You start going down a really bad rabbit hole dealing with groundwater impacts,” said Amstadt. “The other problem to that is just the sheer volume of waste and at a disposal cost of $60 a ton you are talking millions of dollars to remove that waste.”.
Council feedback and cost projections
Alderperson Steve Willis questioned if the current proposal was too limited in scope because it primarily focused on one side of the landfill.
“It sounds like this would remediate the east side but the west side does not have any remediation in this proposal,” said Willis.
Amstadt clarified that the current step acts as a barrier for the nearby housing development while the city designs the broader active system.
Alderperson Todd Spaeth inquired about the long term operational requirements and whether an active system could eventually be turned off.
“Methane just decreases as time goes on,” said Spaeth. “Is it possible in the future to eliminate the active system and go back to a venting system?”
Amstadt responded that the system would likely need to run for many years before the biological activity in the waste mass slowed down enough to stop mechanical vacuuming.
Alderperson Cyndy Hubbard asked about the environmental impact of flaring the gas and if there were ways to reclaim energy from the methane.
“Aren’t there cities that use those flares to produce electricity somehow?” asked Hubbard..
Amstadt explained that energy reclamation typically requires a much higher volume and quality of gas than what is being generated at the old city dump.
Approved actions and financials
One of the immediate concerns was the protection of the area just to the north of the east section of the site. Construction of the infrastructure (streets, storm water pond and utilities) is currently underway on the 23 acre site just north of the east section of the old dump site. Amstad and Grainger recommended the installation of clay “cut off” trench at part of that construction that would prevent methane infiltration to the area even if an active blower type system would fail.
As part of this years budget the city borrowed $750,000 to address the methane issue and with the $160,00 willhave committed about $561,000.
City Administrator Nate Torres detailed the financial strategy for the project which uses a change order to the existing construction contract to install a specialized clay and gravel barrier. He explained that while the broader development is funded through a state trust fund loan the specific cost for this trench will be covered by funds borrowed in 2025 for landfill remediation.
“The property on the Hanson farm will end up being improved two ways,” said Torres. “Mostly through the state trust fund loan but a portion of which is from the landfill remediation loan we got last year.”
Torres emphasized that the city must take these precautions because the planned residential area is located north of the landfill where methane could otherwise pose a risk to future tenants. He noted that the new clay wall barrier will cut into the sand layer to impede gas movement and protect the residents of the coming development.
“Redundancies are part of what we are trying to accomplish here,” said Torres. “We are looking at significant density to the north and trying to make additional improvements with this landfill.”
The council approved the motion to hire Badger Environmental to construct the passive system for a total cost of up to 160,000 dollars. Torres concluded that these steps ensure the city satisfies its obligations to the Department of Natural Resources while allowing the housing project to move forward with confidence.
Additionally, the city approved $15,725 to purchase its own gas monitoring meter to eliminate high monthly rental fees. Administrator Nate Torres clarified that the city would continue to look for grant funding to offset the high costs of the future active system.
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