The Federal Communications Commission’s (FCC) Wireless Telecommunications Bureau seeks comment from freight and passenger railroads, as well as other interested parties, on radio spectrum issues relating to the implementation of positive train control (PTC) systems as mandated by the Rail Safety Improvement Act of 2008. In response to concerns raised by various railroads in their initial PTC implementation plans, and an assessment of risks to the successful development and implementation of PTC enumerated in a report by the GAO in December, 2010, the FCC is soliciting comments from industry participants to determine “what future proceedings or actions, if any, might facilitate an effective, efficient and timely process for railroads to acquire spectrum” for PTC.  FCC notes specific concerns about limitations on the availability of spectrum in the 220 MHz frequency range, particularly in densely developed metropolitan areas, and seeks comment from industry participants on issues pertinent to radio spectrum needs for the successful deployment of PTC technology.  Comments are due no later than June 20, 2011, and must reference WT Docket No. 11-79.  Comments may be filed electronically through the FCC’s web portal at http://www.fcc.gov/cgb/ecfs/ or through the federal government’s eRulemaking portal at http://www.regulations.gov.  Instructions for filing paper hardcopies are included in the Public Notice.  Reply comments are due no later than July 11, 2011.