An Interior Department whistleblower can return to work, with a retroactive promotion, five years after the department fired him in retaliation for reporting insufficient environmental studies of Alaskan drilling sites, the Office of Special Counsel announced Tuesday.

In 2014, the unnamed Interior Department employee told his supervisors multiple times that the department was issuing drilling permits in Alaska without conducting all of the required legal environmental analysis, but those concerns “failed to gain traction,” according to an OSC report on the matter. In October 2014, he submitted a formal complaint to the Interior Department’s Office of the Inspector General, alleging that the department violated environmental laws regarding a lease sale, and that managers were rushing the environmental review process and changing analyses to “support a predetermined outcome.”

During the subsequent investigation, the inspector general’s office interviewed the whistleblower and a number of his colleagues. According to OSC, within hours of learning of the investigation, officials began to investigate the whistleblower based on a time when the whistleblower called a colleague from his home telephone. Eventually, department officials accused him of running a private business while engaging in telework, among other things, and removed him from his position on Jan. 14, 2016.

OSC concluded that the whistleblower was investigated precisely because he had filed a complaint with the inspector general’s office.

“[The] immediate referral of [the whistleblower] for internal investigation for unspecified ‘misconduct’ within hours of hearing about the OIG’s inquiry is sufficient evidence, standing alone, to infer a causal connection between [his] disclosures and the investigation,” OSC wrote. “Five months had passed since [the whistleblower] called [a colleague] from his home telephone, but [the colleague] only reported it the very same day he learned about the OIG’s review.”

Additionally, OSC found that the evidence supporting the removal of the whistleblower was “weak,” noting that testimony against the whistleblower was “not on its face plausible” and “in crucial respects inconsistent with the evidence.”

OSC issued its investigative report in October 2017, and it has been before the Merit Systems Protection Board since then. This week, a hearing judge approved the settlement agreement between the Interior Department and the whistleblower.

As part of the deal, the whistleblower will be reinstated to his job as an environmental protection specialist at the department. The department will provide him with a retroactive promotion and place him in a “modified chain of command,” as well as restore his annual and sick leave. The whistleblower will also get a time off award, improvements to past performance ratings, priority consideration for any job vacancy for which he is qualified for the next two years, as well as $180,000 in damages and attorney’s fees.

“I am very pleased that OSC was able to negotiate a favorable settlement to return this employee to his previous position,” said Special Counsel Henry Kerner in a statement. “Retaliation can take many forms and is rarely straightforward. After closely reviewing the facts in this case, it became clear that the investigation was launched in retaliation for the employee’s prior whistleblowing activities. I also acknowledge the department’s willingness to settle this case before the hearing, a result that conserves valuable taxpayer resources to reach a mutually agreeable outcome.”