CHARLESTON, W.Va. -- Sentencing of an Upper Big Branch Mine superintendent will be delayed for two months while prosecutors use information he provided to pursue other potential targets in their ongoing criminal investigation of the April 2010 mine disaster.Gary May had been scheduled to be sentenced in August after pleading guilty in a deal with U.S. Attorney Booth Goodwin.Assistant U.S. Attorney Steve Ruby asked for a delay of at least 60 days, and U.S. District Judge Irene Berger rescheduled the sentencing for 1:30 p.m. on Oct. 4 in federal court in Beckley."Defendant is cooperating in an ongoing investigation and the parties need additional time to fully develop the extent of his cooperation before sentencing and the preparation of pre-sentencing materials," Ruby wrote in a court filing on Friday.May has already testified once for federal prosecutors, appearing at the sentencing hearing of a former Massey security chief convicted of lying to investigators and trying to destroy evidence in the mine disaster probe.Depending on how helpful prosecutors view May's cooperation in their pursuit of other Massey officials, government lawyers could ask Berger to reduce his ultimate sentence. May faces up to five years in prison for one felony charge.In March, May admitted to conspiracy to violate mine safety standards and cover up the resulting hazards prior to the April 5, 2010, explosion that killed 29 miners at the Massey Energy operation in Raleigh County.May admitted that he plotted "with others known and unknown" to put coal production ahead of worker safety and to conceal the resulting hazards on numerous occasions at Upper Big Branch.May, 43, of Bloomingrose, admitted that he took part in a scheme to provide advance warning of government inspections and then hide or correct violations before federal agents could make it into working sections of the sprawling mine.For example, May, after learning that federal Mine Safety and Health Administration inspectors were about to sample the level of coal dust in the mine, "surreptitiously redirected" additional fresh air to the area to conceal actual working conditions in the mine.May also "caused and ordered" the disabling of a methane monitor on a continuous mining machine at Upper Big Branch less than two months before the deadly blast.May also ordered an unnamed person to falsify mine examination records by omitting a hazardous condition -- high water that could endanger workers and interfere with the flow of fresh air through underground tunnels. This is required to be reported and then fixed.So far, May is the third person to be charged in the sprawling federal criminal investigation at Upper Big Branch.Thomas Harrah, a former miner at the site, was sentenced to 10 months in jail after he admitted to faking a foreman's license when he performed key mine safety examinations at the mine between January 2008 and August 2009 and to then lying to investigators about his actions.Former Massey Energy security director Hughie Elbert Stover is appealing a three-year jail sentence he received after being convicted of lying to investigators and trying to destroy evidence about Massey's practice of warning underground workers of impending government inspections.In December, Goodwin and his team secured a $209.5 million settlement with Alpha Natural Resources, which acquired the Upper Big Branch Mine when it bought Massey Energy.Goodwin agreed not to prosecute the company for any Upper Big Branch criminal liabilities, but required Alpha to spend $80 million over the next two years on mine safety improvements and create a $48 million mine safety research trust fund. Alpha also agreed to pay $46.5 million in restitution to families of the disaster victims and $35 million to resolve pending Massey safety fines, including $10.8 million levied for violations related to the Upper Big Branch explosion.The settlement with Alpha, however, did not prohibit prosecutors from pursuing charges against any individuals -- including Massey officers, employees or agents -- who played a role in the mine disaster.Last week, Alpha filed with Goodwin a required six-month report on its progress in meeting the terms of the settlement. Goodwin has so far refused to comment on it or indicate if he would publicly release Alpha's report.Reach Ken Ward Jr. at email@example.com or 304-348-1702.