For CDs/DVDs with small scratches the library has a machine that will buff discs and repair scratches. Deep scratches and cracked discs cannot be repaired.
The Disc Repair Waiver form states:
I understand the repair of my CD/DVDs may not be possible. I agree to be responsible for the fee of $2.00 per disc ($4.00 for double-sided). All fees must be paid in advance. The Library is NOT responsible for damages that may occur during the repair process. ID is required upon pick up. I understand that upon completion of repairs, I have 30 days to pick up my disc(s) after which the disc(s) become the property of the Library to dispose of at its discretion.