The information likely had been on the site for years, Chief Operating Officer John Byrne said.
Fortunately, it wasn't easy to find, and there are no indications the snafu resulted in identity theft, Byrne said.
The sensitive information has been removed from public view, he said.
"Once I heard about it, it was gone within 10 minutes," commission Chairman Bruce Barclay said.
The glitch was noticed yesterday morning by an employee who was scanning the Web site, Byrne said.
He said the Social Security numbers were included in minutes from salary board meetings dating from 1999 and earlier.
Those minutes, posted on www.ccpa.net, included records listing Social Security numbers of workers who were hired or promoted or had their salaries changed by the board, he said.
At that time, Social Security numbers were used by the salary board for worker identification. Byrne said the county shifted to an identification system independent of Social Security numbers in 2000.
Employees will receive notices of the situation with their paychecks, he said.
All departments that scan in public documents for inclusion on the Web site are being reminded to be careful not to place sensitive personal information on public view, Byrne said.
The site will now allow access to county meeting minutes only for the last two years, he said.
Older minutes will be available for review at the courthouse.