It's more a trickle than a flood so far, but the expected surge of sentence reductions for people convicted of crimes involving crack cocaine has begun.

New, retroactive sentencing guidelines approved in December by the U.S. Sentencing Commission took effect Monday.

Federal judges in the Western District of Virginia in the past week disposed of at least 13 of what are anticipated to be hundreds of requests for sentence changes, granting reductions to nine defendants and rejecting applications from four others.

No one has been set free -- yet. But research by the district's probation office indicates that more than 100 people convicted in the district likely qualify for reductions this year that will bring their sentences below the amount of time they've already served.

William "Buddy" Ross, chief probation officer for the Western District, said he'll have firmer numbers later this week, but about 566 people convicted in the district are eligible for reduced sentences under the new guidelines. Sixty-three are eligible for immediate release, and another 50 may qualify for release by the end of this year, he said.

Those numbers are somewhat higher than the sentencing commission's initial projections, which in a national ranking listed the Western District as having the fourth-most cases affected by the new guidelines.

The commission had predicted that the district with the most cases would be the Eastern District of Virginia. Observers said the high numbers probably reflected law enforcement authorities' willingness to seek the more severe penalties available in federal court.

The old federal guidelines were built around a much-criticized disparity that required someone to possess 100 grams of powder cocaine to trigger the same penalties as possessing 1 gram of crack.

Because crack is powder cocaine that has been processed for smoking rather than snorting, critics said the legal system punished methods of taking the drug -- which tended to differ along racial lines -- rather than the actual drug use itself. Of an estimated 19,500 people across the country who could have their sentences reduced, 16,700 are black, the sentencing commission reported last year.

Larry Shelton, who leads the Western District's public defender's office, called the new guidelines "a first step to equalize the discrepancy between powder and crack.

"The defense bar welcomes this across the nation," he added.

Left in place by the change is the federal system of mandatory minimum penalties, though some members of Congress have called for an equalizing of crack and powder cocaine there as well.

Phil Williams, the Western District's deputy chief probation officer, said the district's judges wanted to consider all eligible cases, not just those in which prisoners filed legal motions to have their sentences reviewed.

Williams spearheaded an effort to pull the files on every crack case in the district -- some 1,000 defendants, he said -- and see who met the requirements of the new guidelines. Defendants might not qualify for a variety of reasons, such as if their crime involved a gun.

That review was largely completed last month, mostly by probation officers putting in extra hours. The office's routine supervision duties were not affected, Williams emphasized.

Now, "the hard part's over," he said.

The U.S. Attorney's Office has objected to reductions in many of the cases prisoners have filed so far. U.S. Attorney John Brownlee declined to comment Monday on whether prosecutors will object to all reductions.

In orders issued in the past week, judges reduced sentences anywhere from five to 37 months. In many more cases, notices have been sent to the prisoner and prosecutor saying the judge intends to reduce the sentence later this month unless a compelling argument is made against it.

Roanoke lawyer Terry Grimes, who has defended people in federal cases tied to crack, said he'd heard judges express regret that the old guidelines required them to send someone to prison for so long.

Many people charged with possessing or selling crack are young, Grimes said. Sending them to prison for decades "really takes away a future and a hope for them."