DeKalb CEO Michael Thurmond says he wants to put new safeguards in place to tighten the county’s purchasing system and prevent contractors from billing the county for work they weren’t authorized to do.

These changes come at the same time that Channel 2 Action News has questioned changes to DeKalb’s agreement with Tetra Tech, a company hired to manage the expansion of the Snapfinger wastewater treatment plant.

Tetra Tech was hired in 2013 to oversee the Snapfinger project, but the company has faced scrutiny recently because it was named in a federal subpoena that DeKalb received in February. The subpoena asked for all documents during the 2014 calendar year related to Tetra Tech.

It’s Snapfinger contract was worth roughly $10 million when the company was hired, but commissioners agreed in late 2016 to add another $7.2 million.

Now there is a second change order in the works that would allow Tetra Tech to earn another $5.9 million.

Related | Feds subpoena more records linked to ex-DeKalb commissioner

The company billed the county for work in 2016 that was beyond the duties outlined in its contract. That out-of-scope work amounted to $2.2 million in the first change order approved by commissioners before Thurmond took office in January 2017, Channel 2 reported.

At the time, the county's Department of Watershed Management director Scott Towler said that Tetra Tech, at the county's request, had started working at Snapfinger before the construction project officially got underway. He encouraged commissioners to authorize the additional payment.

Thurmond took office shortly after and while the agreement was still waiting to be finalized. He signed the document in September after months of negotiations.

Thurmond now says he won’t ask commissioners to approve the new change order until there are additional reviews by staff to ensure it adheres to county policies and clearly defines what new work Tetra Tech will do to justify paying more.

The commission’s Public Works and Infrastructure Committee was scheduled to discuss the second change order on Tuesday, but Thurmond’s staff pulled it from the agenda as Channel 2 was preparing its story.

The February subpoena named two other companies that have also worked on lucrative DeKalb water and sewer projects: Environmental Consortium and Metals and Materials Engineers.

In its 2013 proposal for Snapfinger, Tetra Tech said that it planned to bring the PRAD Group and Environmental Consortium on as subcontractors.

Lohrasb “Jeff” Jafari, PRAD’s former executive vice president, was indicted earlier this year as part of the Atlanta City Hall federal probe. The March indictment outlines 51 charges against Jafari, including an allegation that he bribed an unnamed DeKalb official in 2014.