The new General Motors appears to be thriving.

Having emerged from bankruptcy, the revitalized company has recently reported $1.3 billion in quarterly earnings, paraded out a new chief executive and filed an initial public offering that seeks to pay back a portion of its approximately $60 billion in government loans.

But the old G.M. — a grim collection of shuttered auto plants, vacant office space and toxic industrial sites — is one step closer to extinction.

The fate that awaits the old G.M., officially the Motors Liquidation Company, the entity that houses the unwanted assets that were cleaved off in General Motors’ bankruptcy, was spelled out in its reorganization plan filed late Tuesday in federal bankruptcy court in Manhattan.

The complex plan splits the old G.M. into four trusts, including one financed by $536 million in existing loans from the federal government that will go toward cleaning up auto plants and other properties still owned by Motors Liquidation. The trust will work with 14 states and the Environmental Protection Agency to provide cleanup money to these sites. Another $300 million is earmarked for property taxes, plant security and other expenses.

“A significant number of the properties owned by Motors Liquidation Company are old industrial sites,” said Ted Stenger, an executive at Motors Liquidation and managing director at AlixPartners, the turnaround and consulting firm. “It is nearly impossible to redevelop such properties for productive, job-creating purposes unless environmental remediation is addressed.”

Another trust will handle the claims of the owners of G.M.’s old bonds, which are expected to get 10 percent of the equity in the new G.M. when it goes public later this year, plus warrants to buy additional shares. A recent report by the fixed-income research firm Gimme Credit estimates that bondholders will most likely end up with about 20 percent of the new G.M.

Two other trusts will handle litigation related to the old G.M., including asbestos-related claims. After the plan is approved — the court is expected to sign off on it early next year — the old G.M. will disappear.

“While ‘new G.M.’ is, rightfully, getting a lot of positive attention these days, what’s been accomplished here at so-called ‘old G.M.’ — including work done well before the bankruptcy — is historic in its own right,” said Al Koch, Motors Liquidation’s chief executive and a managing director at AlixPartners.

Mr. Koch said that he expected most of the old G.M. assets would be sold or transferred within four years, while most of the environmental cleanup at the sites — some of which are contaminated with chemicals called PCBs and other toxins — would be completed within a decade.

The process of selling the old G.M. plants and other properties — 50 million square feet of industrial manufacturing space at 127 locations across 14 states — has been slow going.

So far, Motors Liquidation has raised $125 million through asset sales. It has offloaded three former factories: a Wilmington, Del., assembly plant to Fisker Automotive, the startup hybrid car maker; a Pontiac, Mich., factory to Raleigh Studios, an independent film company that is making the space into a movie studio; and a Strasbourg, France, transmission plant, sold back to the new G.M. for one euro.

Another 17 sites are in discussions to be sold, Mr. Koch said. Other properties have received inquiries from all types of buyers. For instance, an investor group has expressed interest in repurposing the historic Buick City auto manufacturing complex near Flint, Mich., into a shipping hub for soybeans.

There have been recent setbacks. J. D. Norman Industries, a metal components manufacturer in Addison, Ill., is near a deal to acquire a former G.M. stamping plant in Indianapolis, but the local union there last week refused to vote on a new contract that would reduce employees’ wages.

Other abandoned plants are being preyed upon by thieves. The police in Flint, Mich., are investigating the theft of copper, said to be worth more than $1 million, from a vacant factory there. Last month, burglars fired shots at the police while making their getaway from the Powertrain Flint North plant.

“This is a major-league problem,” said Robert J. Pickell, the sheriff of Genesee County, Mich., in an interview. “These people are robbing G.M. blind.”

Seven months after laid off Freightliner workers won back pay and benefits in arbitration, none of them have received a dime.

On Tuesday, four laid off Freightliner workers filed a class action lawsuit in federal court to enforce the arbitration award.

Back in January, arbitrator Robert B. Moberly, a labor law expert and professor at the University of Arkansas School of Law, found Daimler Trucks North America in violation of its 2006 labor agreement, which required the company to make 70 percent of the M-2 business class truck at its Mount Holly plant through April 2, 2010.

Moberly ordered DTNA to compensate roughly 900 employees laid off from the Mount Holly plant in October 2008 and March 2009, during which time the company was outsourcing M-2 production to its plant in Santiago, Mexico.

DTNA and the United Auto Workers were charged with settling on the amount owed to workers. Union officials say they are still working diligently to come to terms with DTNA.

But that effort has not been speedy enough for Charles R. Hall Jr., John O’Neill Jr., Timothy L. Phillips and Charlie R. Wooten, who sued both DTNA and the UAW.

“[B]y the time the Arbitration Award was determined, many of said individuals and their families were financially ruined and could ill afford yet further and additional delay in the enforcement of the Arbitration Award by Defendant UAW or the continued failure of Defendant Daimler Trucks to make them whole…,” plaintiff’s attorney Chet Rabon stated in the complaint.

DTNA spokeswoman Maria McCullough said Tuesday that the company “has not been served with a complaint and we are unable to comment at this time.”

On the UAW website, Local 5285 president Ricky McDowell said the UAW Heavy Truck Department is “working hard to resolve this settlement. The issue of total manpower hours per truck is still in dispute.”

According to the complaint, affected union workers don’t know when the arbitration award will be paid and they don’t know the amount to be paid. However, plaintiffs say McDowell told them in April the amount was about “$34 million and growing.”

Hall, O’Neill, Phillips and Wooten were all laid off in October 2008 after working at the Mount Holly truck manufacturing plant for more than 20 years.

Union officials have announced the recall of as many as 273 workers to the Mount Holly plant as production increased following ratification of a new three-year agreement April 17. The plaintiffs have not been recalled, according to the lawsuit.

Plaintiffs say DTNA also failed to comply with the arbitrator’s order to increase production in Mount Holly to 70 percent of all M-2 trucks sold in North America as required by the 2006 collective bargaining agreement, which expired in April.

Had production increased prior to April, any recalled workers would have been entitled to at least six months of company-paid health insurance, according to the complaint.

The new labor contract does not include the 70 percent requirement, but does guarantee baseline production of at least 24 trucks per day in Mount Holly before any M-2 trucks are produced elsewhere.

According to the complaint, UAW breached its duty of fair representation by failing to expeditiously enforce the arbitration award.

“These workers who were laid off from Freightliner … have faced some really severe hardships. And in many instances, those have been financially crippling hardships, including foreclosures of their homes, loss of cars, other assets, things like that,” Rabon said Wednesday.

“It’s our goal through this lawsuit to do everything we can to recover for these workers all that they are entitled to …,” Rabon said.

In his ruling, Moberly retained jurisdiction over the settlement should the UAW and DTNA fail to come to terms on the arbitration award.

But the lawsuit asks the court to take jurisdiction, to appoint a “Special Master” to determine damages owed to plaintiffs of the class action and to enter a judgment against DTNA and UAW for payment of those damages with interest.

Gary Casteel, director of UAW Region 8, said Tuesday the union is still negotiating with DTNA on the correct amount of the settlement.

“We’ve not referred it back to the arbitrator,” he said.