There is no definition of a corrosive solid in the RCRA hazardous waste regulations.
However, the following guidance documents provide additional guidance on corrosive solids:
Memo, Hansen to Licht; March 9, 1992 (RCRA Online #13533)
Memo, Straus to Rookstool; August 18, 1987 (RCRA Online #11278)
In addition, it is important to note that this guidance represents clarification of the Federal regulations. Most states are authorized to implement the Federal regulations. We recommend that you also contact your state's implementing agency to acquire additional information on the characteristic of corrosivity. The Office of Resource Conservation and Recovery (ORCR) has compiled a complete list of phone numbers and waste program Web sites maintained by EPA Regional offices and state environmental agencies to help users locate the appropriate agency within their states.
This compilation is found at the following URL: http://www.epa.gov/epawaste/comments.htm