The second and final phase of the Prince George's County Detention Center has moved a step closer to fruition with the awarding of a contract for the design of the $8.5-million project in Upper Marlboro.

The $288,211 contract, which the county awarded last week to Greenhorne & O'Mara/JBC&W Joint Venture, calls for designing a 108-bed Community Adult Rehabilitation Center, expected to cost $3.8 million to build, and a 300-bed addition to the present detention center, with construction costs estimated at $4.7 million. The additions, to be funded with state and county monies, will complete the detention complex that will eventually house 568 pre-trial detainees, county-sentenced prisoners and some state prisoners.

The first wing, which cost $3.2 million, opened in December 1976 as a replacement for the 49-year-old jail and was filled almost immediately with twice the number of persons it was designed for, according to then-jail director, Sheriff Don E. Ansell. Plans to demolish the old county jail, which is adjacent to the detention center, were delayed, however, when overcrowded conditions in state penitentiaries forced the state to lease the old jail for more than 190 state prisoners now there.

The new addition is expected to solve the overcrowding problem in the county detention center and will be used for state prisoners after the old jail is demolished, according to the county Director of Corrections Weldon McPhail. "When our Phase Two is completed, this place will be comparable to any facility in the country," McPhail said in an interview last week.

McPhail's vision for the Prince George's County Corrections system is a far different one from the county jail history. During the late 1960s and early 1970s, complaints about overcrowded and decaying conditions in th jail led to several prison riots and to criticisms such as those Sheriff Ansell made in 1972 that the jail "was about as inhumane as any tupe of jail can be."

More recently, state prisoners filed a lawsuit last year, charging that inmates in the jail slept on mattresses on the floor in crowded quarters, that their mail was tampered with and that conditions "were so vile as to defy true comprehension by anyone not actually residing within the confines of the Prince George's County Detention Center."

The suit, which was filed against the state in March 1977, was dismissed this June by U.S. District Court Judge Joseph H. Young "for want of prosecution." According to Young's law clerk, Charles Kolb, and court-appointed attorney, Robert D. Clark, the plaintiffs could not be reached by then to file new action in the case. Under Maryland law, Kolb said, any suit pending for more than 12 months with no action by either party can be dismissed on the grounds that nothing had happened to advance the case.

Kolb said that "because all the plaintiffs had been transferred from the detention center," the issues were then "moot." Kolb added, however, that Judge Young visited the detention center in October 1977 and that "most of the inadequancies were remedied."

Clark said he also had visited the detention center and found "improvement. There were some mattresses on the floor in the holding areas and I did see some cells that were overcrowded and bunk beds without sheets and pillows, but constitutional problems did not smack you in the face."

Clark, who is a member of the Maryland State Bar Association Committee on Correctional Reform, said he had "seen worse in Baltimore City where conditions are horrible." Clark said he did not tour the old jail, the source of the complaints in the state prisoners' suit.

McPhail, who became the corrections chief in January in an attempt by County Executive Winfield M. Kelly to "professionalize the correction systems in the county," said that while the detention center is crowded, it is not a "mass of humanity." McPhail said no one is sleeping on the floor but prisoners are sleeping in bunks, "dormitory style," in the center area of cellblocks.

McPhail said the department has hired a recreation specialist to organize daily exercise in the new gymnasium, and the library is "accessible to anyone who desires it." Both areas were cited in th inmates' 1977 lawsuit.

McPhail said the county attempts to provide "a comfortable living arrangement" and he said he meets "regularly with the inmate population to ferret out complaints. We must have one of the few jails (in the country) where people don't complain about food."

McPhail said he has not heard of any lawsuits or formal complaints about the detention centr since he has been with the county. "If we or any institution is not doing what it should, we'll hear about it. You'll get litigation filed against you."

McPhail said he expects to break ground on the new addition and on the Community Adult Rehabilition Center within the next 18 months.

"This is not a perfect society," McPhail said, "but we do know it will get better."