Property owners, local governments, and public interest groups will be able to call witnesses and provide testimony in a case that will determine whether the Maryland Piedmont Reliability Project, a proposed 70-mile power line through Baltimore, Carroll and Frederick counties, will be allowed to begin construction.

The proposed project must receive a Certificate of Public Convenience and Necessity from the Maryland Public Service Commission before construction can begin. The commission announced Friday that 127 entities who filed petitions to intervene will be able to provide evidence in that process. The entities include 116 landowners with property on the project path, six public interest groups, Baltimore County, Carroll County, Frederick County, Del. Nino Mangione of Baltimore County, and the Potomac Edison Company.

“We are pleased that the Public Service Commission agreed with our position that only the county can adequately represent its particular interest in this matter,” Carroll County Commissioner President Ken Kiler said in a statement, “and that intervention by the county was warranted.”

The Public Service Enterprise Group was contracted by PJM, the organization responsible for operating and planning Maryland’s electric grid, to build the $424 million project. PSEG spokesperson William Smith declined to comment on the commission granting intervener status.

Intervener status was granted to the public interest groups STOP MPRP, the Land Preservation Trust, the Maryland Farm Bureau, the Sierra Club, the Gunpowder Riverkeeper and the Potomac Riverkeeper Network. Joanne Frederick of STOP MPRP, Inc., said she is happy that the organization was named an intervener.

“It’s a great decision,” Frederick said. “It allows the organization to represent all of our members, and particularly those members who did not file their own petition to intervene.”

Stop MPRP does not yet have a specific plan for coordinated witnesses and testimony, but Frederick said collaboration among interveners is possible. The organization will do everything in its power to highlight how the project will be bad for Marylanders, she added.

“This project, the MPRP, is really catastrophic on very many levels,” Frederick said, “including environmental, including property values, including farming, including conserved and preserved land. We intend to ensure that each of those, and all topics about the impact of this project, are fully heard by the Public Service Commission.”

Del. Nino Mangione, who represents Baltimore County and has publicly opposed the power line project, said he filed a petition to intervene to represent the interests of his constituents.

“Every elected official should do everything they can to stop this MPRP project,” Mangione said, “and if intervention is a potential tool, I support that. If there are other personal ways or collective ways they can help support our efforts to stop this, I support that. I availed myself of this process because I thought that I have standing here, to really take the opportunity, and, after what I’ve learned, to put it in as evidence, and to represent the people that are in my district, and to try to help in this fight against this power company.”

Mangione said he plans to do everything in his power to oppose the project.

Frederick said the high number of granted petitions indicates how far-reaching the project’s impacts would be.

“The extraordinary number of intervenors really points back to the extraordinary and far-reaching destructive impact this project would have should it get approved,” Frederick said. “There are hundreds of people across the three counties, and hundreds of pieces of property across the three counties, that will be negatively impacted should this line get approved, and the number of interveners is directly related to the extensive negative impact.”

A conference to determine the timetable for the proceeding has yet to be scheduled, Frederick said.The commission reviewed 176 petitions to intervene and granted interested person status to an additional 48 landowners, which allows them to express concerns without requiring formal testimony.

PSEG filed for a Certificate of Public Convenience and Necessity for the power line project with the Maryland Public Service Commission in December. The commission will typically render a decision in nine months to a year, though it could take longer for complex cases, according to Tori Leonard, a spokesperson for the commission.

Contact Thomas Goodwin Smith at thsmith@baltsun.com.