Those who would be out of work included more than 1,100 union members employed by refinery contractors, according to the study.
The closings would also mean job losses at local restaurants and bars, and in other service industries. "All the other business are utterly dependent on the disposable income that's not going to be available," Carey said.
As of Jan. 31, ConocoPhillips had laid off 413 employees at its idled Trainer plant, with severance packages ranging from one to 60 weeks, the county said.
Sunoco has notified the state it planned to lay off 420 workers, probably by the end of the month. Negotiations on severance packages were continuing.
The county said it was trying to find work for the displaced refinery employees, adding that it had joined the state in applying for a $5 million federal grant to aid the workers.
The oil companies say they are getting out of the refinery business because it is unprofitable.
In addition to employees, the refiners' decisions could have a significant impact on local governments and schools.
The refineries pay about $3.8 million annually in property taxes to the Chichester School District. Counting local wage levies, the refineries account for as much as half of the towns' tax revenue.
But it will be some time before the full economic effects are measured.
Said Carey: "We aren't going to know how bad the storm is for six months."
Contact staff writer Anthony R. Wood at 610-761-8423 or twood@phillynews.com.