A San Francisco Bay Area Rapid Transit (BART) janitor made $271,243 last year, quadruple of his base salary, based on $162,050 in overtime pay and other compensation, according to public pay data

Transparent California, which compiled compensation data for a number of public sector employees, released 2015 public compensation data Tuesday for over 100,000 special district workers statewide.

According to the report, Liang Zhao Zhang, who worked an average of 114 hours a week last year, received a combined compensation of $682,000 over the last three years.

His base salary is $57,945.

Zhang was the only service worker to make over $200,000 in 2014, the 2015 report shows four BART janitors, all of whom received overtime payouts in excess of their regular salaries.

Transparent California’s research director Robert Fellner said the high concentration of overtime among a select few BART employees appeared to violate the agency’s guidelines that overtime pay be “rotated equally.”

“It’d be great if all janitors were paid $200k, but I seriously doubt many of BART’s riders — who must pay for this excess — are ever afforded that opportunity,” Fellner said.

BART spokesperson Alicia Trost defended Zhang’s compensation.

“This employee signs up for every overtime slot that becomes available. He is likely working almost every day of the year cleaning our stations. He is signing up for time that is also available to others- if he doesn’t take them, someone else will,” Trost said.

Fellner said that even without benefits, the average BART service worker made $77,777 last year, triple of what janitors made in the rest of the country.

BART spent over $470 million on employee compensation last year, 10 percent more than 2014.

“Station cleanliness is a priority for us,” Trost said. “If we didn’t have system service workers working overtime, our stations would be more dirty and the overall BART experience would be impacted.”

Trost said overtime for BART service employees was available for a number of reasons: vacation and sick leave backfill, special events such as games, parades, or when stations have a tremendous need.

“We try to balance the right level of staffing and overtime. Hiring more employees would cost more than paying overtime,” Trost said.

Top Bay Area earners:

Washington Hospital Healthcare System CEO Nancy Farber was the highest paid special district worker in the Bay Area, with a $931,839 compensation package.

The three highest-compensated Bay Area special district workers, excluding hospitals or health care systems were:

1. San Ramon Valley fire chief Paige Meyer, with $510,671 in compensation

2. San Ramon Valley battalion chief Daniel McNamara, with $485,251.

3. East Bay Municipal Utility District GM Alexander Coate, with $478,077.

For more information on all state and local government pay visit TransparentCalifornia.