WORTHINGTON, Pa. (AP) _ A mushroom farm manager trying to uncover a bathroom vandal is charged with illegally taping his employees' restroom conversations.

Edward Fosnaught, a group manager for Moonlight Mushroom, faces a preliminary hearing Nov. 21 on a charge of unlawful interception, disclosure or use of wire, electronic or oral communication.

He allegedly hid a sound-activated microcasette recorder in the ventilation duct of an employee restroom, state police said. The device was discovered Oct. 13.

''It was a total invasion of privacy,'' said David Bowser, a harvester at the underground mine.

''You can hear zippers going up and down on the tape ... you can hear everything. I heard my voice on that tape and I think of the four or five people on the tape, I was upset the most.''

Fosnaught declined to comment on the charge, a third-degree felony carrying a maximum prison sentence of seven years. The company also refused to comment.

Bowser said management has apologized to the mine's 1,100 employees, who were told the company was trying to determine who was vandalizing the bathroom.