The tool that you are looking for is called the CleanWipe tool. You will need to contact support and open a case to get this tool. Make sure to put in the case abstract "requesting CleanWipe tool".
Online -http://www.symantec.com/connect/security/forums/endpoint-protection-antivirus
Phone - http://www.symantec.com/business/support/contact_techsupp_static.jsp