Pennsylvania finally closed the gates on the 89-year-old State Correctional Institution Graterford on Sunday, after the last bus drove out of the gray-walled complex and into the neighboring razor-fenced SCI Phoenix, which has replaced Graterford as the state's largest prison and where most Philadelphia-area convicts serve their sentences.

With beds for more than 3,800, plus 200 in a women's unit and 200 in a transitional unit outside the fence, Phoenix is also one of the largest prisons in the United States, where more modern prisons, including the state institution at Chester, typically house around 1,000.

But Phoenix isn't full. After the last bus emerged from the wall port at Graterford and bounced over the hill to Phoenix, the inmate population at the new prison stood at 2,633, leaving enough space to house a prison the size of the one in Chester.

Pennsylvania Department of Corrections

Indeed, the state had spent the previous few months moving hundreds of Graterford inmates to other prisons upstate, according to inmates and visitors. "Graterford was downsized ahead of the move for safety and security and ease of transition," confirmed state prison spokeswoman Amy Worden. "The population will be brought back up gradually. This was a massive logistical operation."

State Corrections Secretary John Wetzel expects most inmates will eventually be doubled in 9-by-12-foot cells in Phoenix's two-story housing units. But for now, the many long-serving Graterford inmates who had similar-size cells to themselves still have singles.

The longer the prison operates significantly below its capacity but with full staff and utilities — including air-conditioning, which Graterford partly lacked — the longer until Phoenix will likely be able to reduce costs below the $100 per inmate per day that most of Pennsylvania's prisons now spend.

Wetzel has said lower operating costs would justify the expense of the prison, the second-most-expensive building Pennsylvania has built, after the Convention Center. Wetzel said in 2016 the department hoped to cut costs by $30 a day, or around $44 million a year, when the prison is at capacity.

What else hasn’t been settled is the final cost of Phoenix, which opens more than 3½ years after its scheduled November 2014 completion date. The job, first bid in the 2000s by Gov. Ed Rendell under a union-management “project-labor agreement,” was rebid under Gov. Tom Corbett as a “design-build” arrangement under which Hill International Ltd. of Philadelphia was supposed to represent the state in ensuring the work got done on time.

The Department of General Services, which oversees state construction projects, paid Walsh Heery Joint Venture, a Pittsburgh-based conglomeration of two general contractors (from Atlanta and Chicago), a total of $352.4 million to build the prison, plus $44.9 million in design and other "soft costs."

But instead of delivering a finished prison on schedule in 2015, Hill and Walsh Heery squabbled for more than a year over whether Phoenix was ready for final inspection. The state has warned Walsh Heery it will enforce the construction contract and hold the company liable for liquidated damages at the rate of $35,000 a day since the 2014 completion date came and went. Walsh Heery representatives have contended the delays were Hill's fault and it shouldn't have to pay back taxpayers.

Last year, the state hired Urban Engineers of Philadelphia to make sure the contractors fixed insulation deficiencies and other belated items, and paid that firm $889,000 (part of the "soft costs"). The state also advanced $2 million extra to Walsh Heery to pay subcontractors to finish the job, even as Walsh Heery's late payment count mounted.

By now, the Department of General Services contends, Walsh Heery owes taxpayers $31.3 million in liquidated damages and a refund of the $2 million "good faith" advance from last year, plus possible additional payments, said DGS spokesman Troy Thompson.

The department is "proceeding with the processes and procedures outlined in our contract," including a Field Approval Meeting at which DGS and Walsh Heery will "present and discuss" any remaining claims, Thompson added.

That meeting has not been scheduled. There are still about a dozen final "punch list" items to be resolved, Thompson said: "a broken window, signage, a grease trap, a little erosion near the pond, berm lighting, and sound. Little fixes," on the scale of a $400 million project.

As a former prison, Graterford joins other empty, hulking, narrow-windowed complexes in the Philadelphia area that have so far resisted new and permanent uses, such as Eastern State Penitentiary in Philadelphia's Fairmount section, which Graterford replaced; the city's former Holmesburg Prison, whose stone walls and vacant guard towers loom above I-95 in Northeast Philadelphia; the castle-like former Airy Street Prison in central Norristown; and Broadmeadows, the former Delaware County lockup, next door to the current, privately run county prison north of Media.