SOUTH PORTLAND — NGL Supply Terminal Co. has submitted a revised proposal for a liquefied petroleum gas depot at Rigby Yard that reduces its potential fuel capacity by nearly half.

The city’s code enforcement director recently rejected NGL’s previous proposal, saying it didn’t comply with existing zoning ordinances that limit new fuel storage facilities to 10,000 cubic feet or 74,805 gallons of liquid propane. It’s the third version of a proposal that has generated community dissent since NGL first submitted plans one year ago.

The revised proposal calls for two queuing tracks for rail tank cars instead of four, and would accommodate a total of eight tank cars instead of 16 full and eight empty tank cars. It also calls for removing tank cars from the 10-acre depot to the larger rail yard beyond within 24 hours to avoid violating city ordinances related to fuel storage.

With the changes, the depot’s capacity drops from 504,000 gallons to 264,000 gallons, including a 24,000 gallon fixed storage tank where delivery trucks would load propane. The revised proposal also addresses a variety of questions and concerns from the city’s planning staff and residents about the project’s drainage, stormwater management and fire suppression systems, among other things.

“The proposed facility will incorporate the most advanced operational and firefighting technology available, making it safer than our existing depot in Portland, which has operated for over five decades without any calls, complaints or incidents,” Kevin Fitzgerald, NGL’s regional operations manager, said Thursday in a prepared statement.

The $3 million project is tentatively scheduled to go before the Planning Board for site plan review on Feb. 23.

NGL is a subsidiary of NGL Energy Partners of Tulsa, Oklahoma, which includes Brunswick-based Downeast Energy. The company wants to build a depot at Rigby Yard because it must leave its leased site on Commercial Street in Portland by this spring to make way for the planned expansion of the International Marine Terminal.

Opponents of NGL’s proposal say it poses a public safety threat to commercial and residential properties near the 245-acre rail yard off Route 1, between the Thornton Heights and Cash Corner neighborhoods. Local fire officials have vouched for the safety of the project, noting that as many as 100 rail cars loaded with propane pass through Rigby Yard daily with little local security or oversight.

City Councilor Brad Fox, who has led a group of residents who oppose the proposal, wasn’t impressed by the revised version.

“NGL’s latest plan is just another attempt to circumvent our city ordinances,” Fox said in a prepared statement. “I have no doubt that our city staff will reject it as such because they want to protect our residents’ health and safety from this latest … scheme.”

Municipal staff members didn’t respond to a request for comment Thursday.

On Monday, the City Council is expected to consider a fire code amendment, drafted by residents and proposed by Fox, that could block future construction of a propane depot at Rigby Yard. City staffers were directed to review and polish the amendment before the council voted on it.

The citizen-drafted version called for propane storage and distribution facilities to be developed at least 1,257 feet from anything considered “critical infrastructure,” including schools, hospitals, medical clinics, public utilities, telecommunications and government buildings such as the Cash Corner Fire Station near Rigby Yard.