Steve Norton, of Boston, paid pounds 10 for the obsolete machine dumped by the department at a recycling depot at Spalding.
The computer repairman was shocked to find the details of how youngsters were abused and their names and addresses.
"The worst thing is it would have taken under a minute to wipe these records clean," he said. ""This information could have fallen into unscrupulous hands - and it doesn't bear thinking about what could have happened then."
Speaking today social services manager Mike Boddy said: "I am obviously very disturbed to hear that confidential social services files have been disposed of in this fashion. A full investigation is under way to ascertain how this situation arose."Reuse content