BECKLEY, W.Va. -- A former Massey Energy executive who is cooperating with the criminal investigation into the Upper Big Branch mine disaster is asking a judge for leniency when she sentences him Aug. 1.David Hughart's life has been ruined by the "terrible negativity" and publicity surrounding his case, which his defense attorney says has unfairly linked him to the April 2010 explosion that killed 29 men.Hughart worked for a different Massey subsidiary, left the company long before the blast and "never worked a day at UBB," attorney Michael Whitt said in a sentencing memorandum for U.S. District Judge Irene Berger. Yet, "he has gone from affluent to totally destitute as a result of his crime."Hughart pleaded guilty to two federal charges of conspiracy in February, admitting he worked with others to give miners at another Massey subsidiary, White Buck Coal Co., illegal warning about surprise federal inspections. At his plea hearing, Hughart implicated former chief executive Don Blankenship in the scheme.Massey is now owned by Virginia-based Alpha Natural Resources, and Blankenship has long since retired.Hughart faces up to six years in prison and a fine of up to $350,000 when he is sentenced. He doesn't contest his crimes but contends none of his actions "can be linked to any actual mining injury."Assistant U.S. Attorney Steve Ruby, however, urges the court to consider a stiffer sentence because the conspiracy endangered miners' lives."Common sense dictates that when a defendant risks other people's lives and health, that fact must be accounted for in fashioning his sentence," Ruby wrote. Treating this conspiracy like one that created only financial harm "would understate the seriousness of this offense."Hughart's cooperation has been valuable, Ruby said, and it's possible it will eventually warrant a request for leniency. But he said it's too soon to determine that now.Hughart was president of "an important Massey subsidiary." Ruby said. "He enjoyed vast discretion over the mines and facilities that were under his direction, and he used it to flout the law on miners' health and safety."Whitt says his client now sees the error of his ways and understands that he was wrongly informed that the company had the legal right to warn workers when inspections were imminent."David has come to know that mine safety laws are not suggestions," Whitt wrote. "... Prison can do nothing to reinforce this fact."Hughart, he said, "deeply regrets his criminal conduct and that such conduct was part of 'business as usual' under former Massey management."A former Upper Big Branch superintendent and security chief are already behind bars for similar actions at that mine.