NEW CASTLE — A long-awaited merger between Jameson Health System and UPMC has received the green light to proceed after a final legal document was filed Monday in Pittsburgh.

Jameson spokesman Lisa Lombardo said the merger should be completed by May 1.

The final order, which was filed with U.S. District Court, requires that the new entity — referred to as UPMC Jameson — maintain all contracts Jameson has with health plans through their expiration dates. The order also requires UPMC to contract with all health plans that want an agreement with Jameson for 10 years.

If a health plan and UPMC cannot agree on terms, the final order provides for “last best offer” arbitration to set those terms. It also limits UPMC’s ability to create health plan contracts that keep providers from contracting with non-UPMC health care providers.

Also under the terms of the consent decree, UPMC Jameson must remain an acute care hospital at Jameson Memorial Hospital’s current north campus for at least 10 years following the closing of UPMC’s acquisition of the health system.

During that time, the facility must maintain an “appropriate” level of inpatient and outpatient services as well as specific services, including emergency care, general surgery, prenatal and postnatal obstetrical care, orthopedic surgery, neurology, urology and other services.

The hospital’s north campus is a 254-bed facility with more than 220 physicians and houses the majority of the health system’s 1,330 employees, according to Jameson’s website.

The consent decree also requires UPMC to appoint and pay an ombudsman to assist the attorney general’s office in responding to and resolving any complaints for 10 years.

In a press release Tuesday announcing the final agreement, which comes in the form of a consent degree allowing UPMC to acquire Jameson, the Pennsylvania attorney general called the deal “a step toward ... ensur(ING) that people have access to affordable health care,” in Lawrence County and the surrounding area.

Regulators working out of the attorney general’s office had opposed a UPMC-Jameson merger since spring of 2015 amid antitrust concerns, saying the resulting health system had the potential to control too large a share of the health care market.

Late last year the attorney general asked Jameson to search for other partners to merge with. Jameson agreed, but ultimately said a months-long process had failed to produce qualifying bids from potential partners.

State officials disagreed, and the two parties ultimately went before a retired federal district judge to decide the matter. Judge Donald Ziegler ruled in January that the new bids failed to meet Jameson’s qualifications, and the binding ruling resulted in state officials working with UPMC to create the final order filed Monday.

There was no immediate information Tuesday on how long it might take the two health systems to begin or close merger proceedings. The Jameson-UPMC deal has been valued at $80 million.

“We continue to believe this merger is the strongest solution for a healthy future for Lawrence County, its residents, and surrounding communities,” Lombardo said.