Matt Jones, a founding partner of Struct/Restruct, looks out from the base of a bur oak tree near the eastern edge of a plot of land in East Lawrence at 12th Street and Haskell Avenue. Struct/Restruct, which owns the land, planned to sell the lot that contains the tree to the city of Lawrence for 8,000. The tree is believed to be one of the largest in the state.

The possibility of contamination could put a halt to the city’s efforts to preserve a large bur oak tree bordering Brook Creek Park.

Lawrence is considering spending $58,000 to save the more than 100-year-old tree, but not before the city can guarantee it’s not liable for future environmental issues on the site. Commissioner Lisa Larsen, an environmental geologist, said such a safeguard is not out of the ordinary given the history of the area.

“I do think, all in all, it’s the best use for the property to have the city make it into a park and save that tree, but we still need to have that protection from any potential future liability,” Larsen said.

The lot containing the tree is nearby a former salvage yard at 12th Street and Haskell Avenue. Larsen formerly owned the environmental consulting firm that assessed the site. Earlier this month, the purchase of the lot was on the City Commission’s consent agenda, but was removed and deferred after Larsen suggested adding the indemnification language.

Larsen said the previously completed environmental assessment indicated that there was a recognized environmental condition because of the salvage yard. She said an indemnification is pretty common language to have in a contract for a property where there’s been activity considered potentially environmentally hazardous, and that the commission should make sure the city is protected.

“Whether or not there has been contamination detected, there is a recognized environmental condition and that is what I think is important to understand,” Larsen said.

Struct/Restruct, a Lawrence-based design and construction firm, owns the lot and adjoining property and has plans to build eight houses on the site. As part of the sale of the lot containing the tree to the city, Struct/Restruct would donate an additional 2.3 acres of open space that is just north of the housing development.

The appraisal of the lots states it is “subject to the extraordinary assumption that no environmental contamination exists.” It states that if any contamination is found, the value of the appraisal would be affected. The indemnification language would protect the city if environmental contamination requiring remediation is discovered on the properties in the future.

According to a city staff memo to the commission, the owners of Struct/Restruct told city staff they do not want to add indemnification language to the purchase and donation agreements for the lots. Instead, they are asking the commission to consider the agreements as originally proposed.

Absent indemnification language in the contract, city staff is recommending the commission approve the agreement only if an environmental assessment is completed for the two lots. The commission could also vote to deny the agreements or approve them as-is.

On Monday, the city didn’t have a projected cost for the environmental assessment, but Mark Hecker, assistant director of parks recreation, said he hoped to have some estimates for Tuesday’s meeting.

The City Commission will convene at 5:45 p.m. Tuesday at City Hall, 6 E. Sixth St.