After launching SafeTrack, the yearlong maintenance plan designed to ameliorate D.C.’s subway system, Metro General Manager Paul Wiedefeld is turning his sights elsewhere, with staffing cuts hoped to reduce the agency’s costs.

Wiedefeld on Monday sent a memo notifying Metro employees of “the elimination of a total 500 positions over the next several months,” the Washington Post reports. Though the specific positions were not detailed, the general manager said “redundant and other positions not deemed essential to Metro’s core business” would be targeted. The move follows the firing of 20 at-will managers in May—part of a larger organizational “restructuring” as ridership and revenue from it drops.

A Metro spokesperson has not returned City Desk’s request for comment. In the memo obtained by the Post, Wiedefeld writes that the agency is reviewing its policies for staffing cuts, which will trigger at the end of the process. He adds that some of the roles to be eliminated are held by at-will employees while others are held by union members. The latter will receive “proper notifications…in accordance with collective-bargaining agreements,” Wiedefeld goes on to point out.

City Desk has also reached out to Jackie Jeter, the president of the local union that represents the majority of Metro’s approximately 13,000 employees, and will update this post if we hear back. A four-year contract is set to expire June 30.

Wiedefeld joined the transit agency in November. Metro has a $3 billion budget for the next fiscal year.

Update, 3:50 p.m.: In a statement, ATU Local 689 said it understands both the “necessity” of its members’ work and “the financial challenges” Metro faces currently without a source of dedicated funding. “Our union shares General Manager Paul Wiedefeld’s priorities of safety, reliability, and financial responsibility,” it said. “We also believe that financial responsibility can be achieved without excessive harm to Metro’s workforce and the millions of riders we transport annually. Local 689 stands prepared to work with Metro to achieve financial responsibility and accountability, and we look forward to working with [Metro] leadership to meet that end with respect to the necessity of the work our members perform.”