HILLSBOROUGH — Jonathan Plymale's mother hung her head, crying, as a judge announced her son would be going to prison, rather than serving probation as his lawyer had requested.

Plymale pleaded guilty Tuesday to two counts of cocaine trafficking and other drug-dealing charges. He will spend 20 months in prison and will be on probation for five years after that. He faces more than six years in prison if he violates the terms of his probation.

Plymale was running a coke business out of his girlfriend's apartment in downtown Chapel Hill. A 2009 UNC-Chapel Hill graduate, he was living in a rented room in the former Pi Lambda Phi fraternity house in Fraternity Court and supplying cocaine to fraternities and sororities.

His girlfriend, Eliza Vaughan, also pleaded guilty to cocaine trafficking and is serving three years' probation.

Plymale said his own addiction got out of control and led him into dealing, and he wants to repay family, friends and the UNC community, which have supported him.

"It's been a dark place for me this last year," he said. "I can't really begin to describe how ashamed and remorseful I am."

In September 2009, Chapel Hill police raided Vaughan's apartment and found eight individuals, some of them using cocaine. Plymale had come back from Burlington with $4,000 worth of bulk cocaine, and some in the group had been dividing it into 1-gram packets for individual sales. Most were just buyers and charged with possession.

"If the officers had arrived a little earlier, they would have actually found them in the act of cutting it up," said District Attorney Jim Woodall.

Officers seized nearly 200 grams of powder cocaine worth thousands of dollars. As Plymale told them they would, they also found an additional 120 grams in small baggies plus $2,000 cash in his room in the frat house.

Plymale's attorney Wayne Harrison implored the judge to consider his client's quick confession and cooperation with police. Superior Court Judge Jim Hardin cut back from Woodall's proposed three-year prison sentence because of Plymale's efforts.

"He did the wrong thing," Harrison said. "But from the instant of his apprehension, he began to try to do the right thing."

jesse.deconto@newsobserver.com or 919-932-8760