On May 11, 2012, the Bureau of Land Management (BLM) published in the Federal Register a proposed rule to regulate hydraulic fracturing on Federal and Indian land. Due to the complexity of the rule and the issues surrounding it, the BLM extended the comment period for 60 days beyond the end of the initial comment period. On May 24, 2013, the BLM published a supplemental notice of proposed rulemaking and request for comment. Key issues in the revised proposed rule include: the use of an expanded set of cement evaluation tools to help ensure that usable water zones have been isolated and protected from contamination and more detailed guidance on how trade secrets claims will be handled. The revised proposed rule would also provide opportunities for the BLM to coordinate standards and processes with individual States and tribes to reduce administrative costs and improve efficiency. This notice extends the public comment period on the revised proposed rule for 60 days beyond the initial comment period.