This document presents data and issues related to the effects on underground injection from the Land Disposal Restrictions (LDR) - Phase IV; Treatment Standards for Newly Identified Mineral Wastes and Toxicity Characteristics Metal Wastes. In this rule. EPA is promulgating LDRs for the newly identified mineral processing wastes are toxicity characteristic metal wastes that have not been covered in previous LDR rulemakings. In addition, this rule makes changes to the Universal Treatment Standards (UTS) for non-wastewaters for selected matals requiring certain wastes covered in previous LDR rulemakings to meet more stringent treatment requirements for some metal underlying hazardous constituents (UHCs). This document provides estimates of the quantities of wastes that will require alternative commerical treatment prior to land disposal as a result of the LDRs and estimates of alternative commercial treatment capacity available to manage wastes restricted from land disposal.