A former Long Island Rail Road signalman was busted Thursday for allegedly lying about inspecting track and electrical connections at the site of a 2019 derailment that snarled Memorial Day weekend travel to the Hamptons, authorities announced.

Stuart Conklin, 63, of Ronkonkoma, claimed on federal forms to have walked the tracks and tested electrical connections before the two-train crash — but video evidence showed otherwise, as The Post reported in 2019.

“Following the derailment, LIRR employees undertook to re-inspect certain pieces of LIRR equipment that had previously been purportedly inspected by Stuart Conklin,” USDOT investigator Robert Stanek stated in the court filings.

“Those re-inspections identified other instances in which bonding wires were either broken or in poor condition — observations that were not included on the most recent inspection forms for the same bonds completed by Conklin.”

The 3 a.m. Saturday derailment in Speonk devastated Memorial Day weekend train service in Suffolk County. No one was injured, but the incident caused $813,000 in damages to the tracks.

Conklin, who made $153,769 in 2018, tendered his resignation six days later on May 31, 2019 — after being confronted with the allegations, along with evidence from a separate probe into his timesheets, prosecutors said.

His colleagues later confirmed to investigators that he had stopped work before getting to the location of the crash on April 26, 2019, despite claiming otherwise on inspection forms, court docs said.

Cellphone data, meanwhile, placed Conklin away from his designated work location “on multiple occasions” while he was collecting wages, Stanek attested in the court filings.

“It was an unconscionable betrayal to all New Yorkers for this signal inspector to allegedly claim a critical piece of Long Island Railroad infrastructure was safe when he didn’t even bother to look at it,” said MTA Inspector General Carolyn Pokorny in a release Thursday.

One railroad source told The Post Conklin’s approach to work was an open secret among his colleagues.

“He basically made his own hours,” the source alleged. 

Conklin appeared in Brooklyn federal court later Thursday, and was released on $25,000 bond under pretrial supervision. He faces up to two years behind bars if convicted.

Conklin’s attorney said prosecutors were overreacting to the charges.

“Stuart Conklin was a hard-working and loyal Long Island rail Road employee,” Atnhony La Pinto told The Post. “I am not convinced that Mr. Conklin‘s conduct rises to the level of criminality.”

LIRR President Phil Eng said in a statement: “The LIRR does not compromise on safety – period. This alleged conduct is a betrayal of the public’s trust and put our customers’ and employees’ lives at risk.”

“We intend to pursue all available civil remedies and we thank the Eastern District of New York, U.S. DOT and MTA Inspector General for their diligent work on this case,” Eng added.