BOSTON >> An 80-year-old man who pleaded guilty to running a sprawling multi-state marijuana-dealing operation faces sentencing in federal court.

Marshall Dion faces up to seven years in prison under a plea agreement with prosecutors who say Dion has been selling marijuana for decades.

In 1985, Dion crashed a single-engine plane in Kenosha County, Wisconsin, and then crawled along a field with two broken ankles as cash floated in the air. He denied that the $112,000 recovered from the crash scene was his.

A stop for speeding in 2013 in Junction City, Kansas, led authorities to Massachusetts and Arizona, where they found about $15 million in cash, nearly 400 pounds of marijuana and ledgers detailing drug deals going back to 1992.

Sentencing is scheduled Thursday afternoon in U.S. District Court in Boston.