WASHINGTON — The Mine Safety and Health Administration needs to do a better job of implementing emergency response plans, including finding a wireless communications system Congress called for in a 2006 mining reform law, the Government Accountability Office said Tuesday.

The report comes just before the Senate will hear Thursday from MSHA head Richard Stickler and other witnesses about the latest efforts to improve mine safety.

Murray Energy chief Bob Murray was expected to testify about last year's accident at the Crandall Canyon Mine in Emery County before the same Senate Appropriations Subcommittee Thursday, but senators have told him he can wait until after MSHA completes its investigation into the accident.

Labor, Health and Human Services, and Education and Related Agencies Subcommittee Chairman Tom Harkin, D-Iowa, and top Republican Arlen Specter, R-Pa., sent a letter obtained by the Deseret Morning News to attorney Barry Levine, saying that they have postponed Murray's appearance, but a subpoena issued in November is still in effect until further notice.

The subcommittee still will hear from Elliot P. Lewis, assistant inspector general for audit in the Labor Department's Inspector General Office. Lewis signed the IG report issued last week that blamed MSHA for negligence leading up to the collapse.

MSHA did not fare well in Tuesday's GAO report either, with the year-long study finding that the agency has not fully implemented the Mine Improvement and New Emergency Response Act, known as the MINER Act, passed in 2006. In a 65-page report, GAO said MSHA needs to give the mines better guidance and oversight as to how to manage and implement emergency response plans called for under the MINER Act.

"It is uncertain whether all miners will be adequately protected in the event of an accident," according to the GAO report. "We found that some plans did not specify the protections to be provided, and the amount of information about these protections varied from plan to plan."

A backlog of permissible breathable air equipment under the MINER Act has forced most mines to wait for it, and MSHA has not determined what technology would be acceptable to use to meet the mid-2009 deadline for wireless communication to help talk to or locate trapped miners, GAO found.