"Further, the information uncovered by PSI's inquiry and at the April 26th hearing suggests that Balfour has continued to mistreat military families and to record inaccurate and incomplete work order data in its internal Yardi system at non-Army installations," added Ossoff and Johnson, the chairman and ranking member of the subcommittee, respectively.

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The Pentagon declined to comment on the letter to Military.com beyond saying the department is aware of it and will respond to the senators' offices.

Asked for comment on the letter, a spokesperson for Balfour Beatty maintained the company’s “top priority is to support the safety, health and wellbeing of our residents, and we always take their concerns seriously.”

“We reconfirmed this to Senator Ossoff when we submitted a formal rebuttal to the Permanent Subcommittee on Investigations indicating that we disagreed with a significant number of the findings in its Staff Report because they were either inaccurate or mischaracterized events,” the spokesperson added. “We have also shared the rebuttal document with the Office of the Secretary of Defense, the Army, the Air Force, and the Navy.”

In December, Balfour Beatty pleaded guilty to defrauding the Army, Air Force and Navy after having been found to have manipulated maintenance records from 2013 to 2019 to obtain performance bonuses as a housing management contractor. As part of the plea, the company agreed to pay $65 million in fines and restitution.

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Last month, Ossoff and Johnson released a report that found issues persisted after 2019 that "bear striking similarities to the types of conduct which Balfour admitted to in its December 2021 guilty plea."

The report focused largely on Fort Gordon in Ossoff's home state of Georgia and detailed residents' struggles to get Balfour Beatty to fix mold, asbestos, roof leaks and other dangerous and unhealthy living conditions.

Balfour Beatty provides housing for 150,000 military residents in 26 states, including more than 15,500 Air Force homes, more than 18,900 Army homes and more than 8,600 Navy homes.

Earlier this month in response to the Senate investigation, the Army announced the commanding general of Army Materiel Command is overseeing a new review of Balfour Beatty housing at Fort Gordon.

The Army is also auditing Balfour Beatty's property management records at Fort Gordon, suspending any requests for performance bonuses in the interim. And the Army's top lawyer is reviewing possible enforcement options, including whether the service can amend contracts with privatized housing operators.

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But in their letter to Austin, Ossoff and Johnson said they are concerned the Army's actions "are not sufficient," while asking for reviews to be expanded to cover the Air Force and Navy.

The pair also asked whether the Defense Department has access to all original maintenance requests submitted by service members and families rather than just the housing companies' internal databases, as well as whether Austin thinks the Pentagon and military services need any additional legal authority to improve oversight of private housing companies.

The senators wrote they are seeking answers to "ensure the welfare of our military service members and their families, and to protect the taxpayers from potential fraud."