After months of discussion and one 30-day extension of Loudoun County’s deadline to opt in to Phase 2 development of Metro’s Silver Line, three Loudoun County supervisors are pushing for another deadline extension, to Dec. 1.

Just hours before a work session Monday night to review financing options for the extension of Metrorail into Loudoun, Supervisors Kenneth D. Reid (R-Leesburg), Geary Higgins (R-Catoctin) and board Vice Chairman Janet Clarke (R-Blue Ridge) released a list of 21 items that they said should be addressed before Loudoun commits to the second phase of construction.

The list included the request to extend Loudoun’s deadline. Loudoun faces a July 4 deadline to decide whether to continue to stay involved in the project.

The supervisors’ list of “additional agreement terms for consideration” included several requests of the Metropolitan Washington Airports Authority and the Washington Metropolitan Area Transit Authority — including that MWAA establish a permanent inspector general’s position to oversee all of its operations, and that WMATA and MWAA agree to have the unanimous approval of all jurisdictions in the compact, not just among their own boards, before committing to any capital expenditures.

The list also calls for additional state funding to offset tolls on the Dulles Toll Road and aims to guarantee that cost overruns will not be Loudoun’s financial responsibility.

The request to delay Loudoun’s deadline decision was among the list’s most significant items. The five-month extension, the memorandum said, would allow the county more time to identify a specific funding strategy for the project and to receive public input on the plan.

Over the past several weeks, supervisors have considered several potential funding sources for the project, including establishing special tax districts, instituting a commercial and industrial tax, and a combination of the two.

On Monday night, the supervisors continued a passionate discussion over which funding options to pursue or abandon. Several supervisors, including Reid and Clarke, have said that a countywide commercial and industrial tax is a “non-starter,” while others have voiced strong opposition to using any money from the county’s general fund to bridge a funding gap.

In a straw vote, the supervisors were split when faced with removing a commercial and industrial tax as an option for funding. Supervisors Eugene A. Delgaudio (R-Sterling), Higgins, Clarke and Reid voted to have it taken off the table; Supervisors Suzanne Volpe (R-Algonkian), Buona, Letourneau and Williams voted to keep it.

Board Chairman Scott K. York (R-At Large), who has also expressed support for Loudoun’s commitment to the project, was absent from the meeting because of a personal matter.

In another straw vote, the majority of the board supported removing the county’s general fund from consideration as a possible funding source. Only Williams and Letourneau said they would like to keep that option open.

In the late hours of Monday’s meeting, supervisors who have voiced support for the rail project — including Ralph Buona (R-Ashburn), Matt Letourneau (R-Dulles) and Shawn Williams (R-Broad Run) — said they were dismayed that the list of additional agreement terms from Higgins, Clarke and Reid had been added to the work session agenda.

Buona said he was “stunned” when he read the memo shortly before the meeting, noting that many of the requested items were well beyond the authority of the Board of Supervisors.

A visibly frustrated Letourneau agreed. Letourneau also released a statement last week to enumerate his position but “didn’t ask the board to take it up as an agenda item at a work session,” he said. “I just don’t know what we’re supposed to do with this, other than have a very divisive debate, which is precisely what we’re doing right now.”

In the memo, Higgins, Reid and Clarke stated that additional time was necessary to resolve the issues identified on the list of considerations.

“We believe that if MWAA, Fairfax County and WMATA truly want to partner with Loudoun County on this project, they will take the time to work through the construction and funding details on this project,” the memo said. “This is not much to ask for in return for a lifetime of commitment from our citizens.”

The Board of Supervisors decided Monday to hold an additional work session to address financing options for the project before the July 4 deadline. As of Tuesday, the meeting had not been scheduled.