Hazardous Waste Management System; Tentative Denial of Petition To Revise the RCRA Corrosivity Hazardous Characteristic

The Environmental Protection Agency (EPA or the Agency) is responding to a rulemaking petition (``the petition'') requesting revision of the Resource Conservation and Recovery Act (RCRA) corrosivity hazardous waste characteristic regulation. The petition requests that the Agency make two changes to the current corrosivity characteristic regulation: revise the regulatory value for defining waste as corrosive from the current value of pH 12.5, to pH 11.5; and expand the scope of the RCRA corrosivity definition to include nonaqueous wastes in addition to the aqueous wastes currently regulated. After careful consideration, the Agency is tentatively denying the petition, since the materials submitted in support of the petition fail to demonstrate that the requested regulatory revisions are warranted, as further explained in this document. The Agency's review of additional materials it identified as relevant to the petition similarly did not demonstrate that any change to the corrosivity characteristic regulation is warranted at this time. The Agency is also soliciting public comment on this tentative denial and the questions raised in this action.