PL/SQL Script to Inactive and Delete Adhoc Roles

DECLARE
  lc_role_name apps.wf_roles.name%TYPE := 'XX_TEST_ROLE';
BEGIN
  wf_directory.setadhocroleexpiration(lc_role_name, sysdate -1 );
  COMMIT;
  wf_directory.setadhocrolestatus( lc_role_name, 'INACTIVE');
  COMMIT;
  wf_directory.deleterole(lc_role_name , 'WF_LOCAL_ROLES' , 0);
  COMMIT;
END;
/

PL/SQL Script to Create Adhoc Role
PL/SQL Script to Remove and Add Users to Adhoc Role

PL/SQL Script to Inactive and Delete Adhoc Role

For Further Reading