Detroit has paid an average of $36,000 per site to remove and replace contaminated backfill dirt at more than 100 demolition sites across the city, stemming from the work of a contractor now under federal investigation.
Tim Palazzolo, head of the Detroit Demolition & Construction Department, provided the cost estimates, remediation updates and strengthened testing practices to cope with the so-called “dirty dirt” scandal during a Monday presentation to members of the City Council.
Palazzolo said just over 100 properties have been excavated so far over the eight-month process. Another 450-plus properties still need to be addressed after being identified as exceeding the state’s soil standards, he said.
“Today, our average fill removal and replacement costs per site is about $34,000,” Palazzolo told the Public Health and Safety Standing Committee. “Once the fill is excavated and hauled off to a landfill, another consultant is brought in to collect samples — which is an additional $2,300.”
That doesn’t account for the initial sampling and analysis of fill material at the sites, which, he said, amounts to another $5,000 to $6,000.
The City Council this spring approved a $3.5 million contract increase with The Mannik and Smith Group, environmental consultants conducting due diligence related to the dirt issues. Originally, a $1 million contract was approved with the consultants for general environmental consulting services. The $3.5 million amendment was to cover costs associated with backfill testing.
City officials have accused Detroit-based Gayanga Co. and its owner, Brian McKinney, of using contaminated dirt to backfill properties. The company and McKinney are the focus of a federal investigation. McKinney announced in May that Gayanga was shutting down and filing a defamation lawsuit against the city, noting the court action “arises from false and materially misleading public statements.”
Detroit’s Office of the Inspector General suspended Gayanga and McKinney last September from doing work in the city after investigators said they found the company was using contaminated dirt to backfill residential demolition sites. The OIG alleged that the company had sourced contaminated dirt from the redevelopment of the former Northland Mall site in Southfield. Gayanga had been awarded tens of millions in city demolition contracts since 2018.
Palazzolo discussed during a Monday presentation the work being done by Mannik and Smith to sample and analyze the backfill material and the demolition department’s process of bringing in contractors to dig up unapproved fill. Then, a third party is brought in to test the excavation to ensure the concerns are remediated before new fill is brought in to finish off the work.
“One of the questions I always get is what have we done to ensure that the unapproved fill sites do not happen,” he said. “We’ve taken some additional measures over the last several months to tighten up our process for approving fill material.”
Palazzolo said the department now sources its materials from just seven public pits with native gravel and soil from longstanding operations – down from 14 source sites previously. Two of the sites are located in Milford and the others are in Pinckney, Washington, Petersburg, Milan and Maybee. The sites are also inspected monthly by the demolition department’s staff and environmental consultants, he said. The demolition department is also sampling and analyzing soil before it leaves the source site.
The changes are all new this calendar year and should “significantly close gaps in the process,” Palazzolo said.
Later this year, the department will conduct random sampling of fill dirt after it leaves approved source locations and is deposited at demolition and fill removal replacement sites in Detroit.
Public Health and Safety Committee Chair Gabriela Santiago-Romero pressed Palazzolo for clarity on the remediation costs and how the work will be funded. Beyond the sites that have already been addressed, she said the remaining 400-plus would likely cost between $15 million and $20 million.
Palazzolo told Santiago-Romero that funding is set aside for the remediation work.
“Technically, at this point, we’re not pulling from any other cost centers,” but “obviously, we’ll cross that bridge when we come to it,” Palazzolo said.
Santiago-Romero responded: “I like to know what bridge is coming up.”
As of June 2026, the city has spent approximately $6.96 million on testing and remediation work associated with this effort. A dedicated cost center was established within the Construction & Demolition Department’s budget for this work using blight funding, Raquel Harrington, a spokesperson for the department, said in an email to BridgeDetroit.
The city’s Law Department has signaled that Detroit would pursue a cost recovery action against Gayanga for total damages.
Santiago-Romero said she was pleased to hear of the added measures in an attempt to avoid a repeat of the dirt issues.
“At this point, we will hope for the best, but we’re really grateful that we are addressing these issues,” she said. “We shouldn’t be risking people’s health with this kind of material around the city.”
Palazzolo noted a couple of property remediations have exceeded the average costs and have come before the City Council for approval. Those were $52,000 and $93,000, respectively.
City Council Member Denzel Anton McCampbell cited widespread concern from the community about potentially contaminated sites from past years outside the scope of the 600-plus identified for remediation.
“Do you have reassurance that folks aren’t dealing with contaminated and unapproved dirt there in those properties (not included in the current group being remediated)?” he said.
Palazzolo said he couldn’t immediately answer the question due to the active investigations.
Earlier in the meeting, Palazzolo said that although there have been materials that exceed the state’s generic residential cleanup criteria, most sites the city has identified “do not present an imminent risk for public health.”
Risks, he said, are “very low,” pointing to how the sites have a foot of fill material that “hasn’t been tampered with” and are also below a layer of vegetation.
“If there are sites that give us concern, we move forward with a rapid removal and replacement process to get those sites excavated and remediated,” he said.
He also noted a public-facing webpage on the testing, removal and replacement process and an FAQ. Questions can be directed to demo-info@detroitmi.gov or (313) 224-4737.
In addition, the department will conduct direct outreach to affected property owners throughout the testing and remediation process, Harrington said in an email.
“This includes mailed notifications, direct outreach to property owners ahead of testing, and informational materials that explain the process and provide points of contact for questions,” she said. “We also provide monthly updates through the City’s Department of Neighborhoods DONCast, where we share updated stats and answer residents’ questions about the unapproved fill remediation efforts.”
