TALLULAH — As LeTourneau Technologies in Warren County said a low-key goodbye to jobs Monday, a new company in Madison Parish — just across the river — celebrated its arrival and promised hundreds of jobs and millions of dollars in spending.

St. John Enterprises Inc. of Garyville, La., plans a $32 million upgrade to cranes, machinery and infrastructure at the 100,000-square-foot, 56-acre site where Northrop Grumman operated for 12 years before the shipbuilder moved operations to Pascagoula last fall. About 50 jobs will remain in Garyville in the cleaning, fleeting and repair divisions.

The official St. John announcement came Monday from CEO Ron Lewis and Louisiana Gov. Bobby Jindal, who met with media and parish and state officials, as well as representatives of auxiliary businesses that are expected to feel the impact of the new industry in the area.

“I asked them to find me 100 and they’ve found me 169 resumes from Louisiana residents,” Lewis said, adding the site’s size and access to the Mississippi River clinched the move over places in Alabama, Tennessee, Mississippi and other places in Louisiana. “We’ll also put a rail spur in the facility.”

Across the river, at LeTourneau in south Warren County, little fanfare was afforded the departure of the $150 million Joe Douglas 240-C class shallow-water rig, now on its way to Sabine Pass, Texas, where more support legs will be added. Its first assignment is in the Gulf of Mexico, according to former parent company Rowan Companies.

LeTourneau Technologies was purchased for $1.1 billion by Joy Global of Milwaukee.

Joy has said 250 people are employed at the plant and the same number is expected to continue. The company previously employed up to 600 jobs as big rig after big rig was manufactured and floated downriver for eventual oil and gas exploration in the world’s waters.

Some of the previous LeTourneau-Rowan workers, particularly those of welders, potentially could find work at St. John, where river-going barges will be built.

Whether more full-scale rigs will be made at LeTourneau is uncertain. Component packages, or “rig kits,” consisting of leg assembly pieces and other parts, are in the offing, including kits and licenses for two mobile jackups to be built by a Chinese shipbuilder by 2014.

“We got a couple of kits we’ll do, but that’s really all I can say right now,” said plant manager Bo-D Massey.

St. John said Monday it wants to hire 104 people within a year, then expand to 454 by 2016. Part of a tax incentive package involves the company’s paying more than $40,000 in average annual pay and benefits. If the company meets payroll and employment goals, the firm receives a $1.4 million performance-based grant to be paid back over 10 years — part of the targeted-recruitment component of Louisiana FastStart, the Louisiana Economic Development department’s work force development program.

Lewis said many of the initial jobs are aimed at local former employees of the Northrop Grumman parts-making plant.

“It’s about bringing jobs back to this country as well,” Jindal said. “It’s particularly important because of the loss of Northrop Grumman. This will more than replace those jobs because they will hire former Northrop Grumman workers. Many would have to leave.”

Unemployment rates in July were 12 percent in Madison and 11.7 percent in Warren County.

Marty Collins, business manager for Rebel Welding and Industrial Supply’s Vicksburg office on U.S. 80, was one of about 75 people inside the Tallulah-Madison Community Center for St. John’s announcement.

“Ultimately, I think it’ll impact Warren County and the region,” he said. “It’s been a long dry spell with these kinds of jobs around here. They come in and ask where somebody’s hiring.”

State Rep. Charles “Bubba” Chaney, R-Rayville, expressed hope laborers will “go back and forth” between LeTourneau and St. John to stay employed.

Terry Hodges, branch manager of the Vicksburg WIN Job Center on Monroe Street, said demand for welders is projected to grow 9 percent in the local area through 2018, citing federal labor statistics.

“Hiring experienced welders continues to be a challenge due to the demand of this occupation,” Hodges said. “Working with local training providers will help in this effort.”

Madison Parish Port Director Clyde Thompson said the immediate jobs are most important.

“When they put 100 jobs out there, with the money, that’s the deal,” he said. “I have a lot of good expectations.”

St. John was founded in 1976 by the late Charles Metcalf and remains owned and operated by the Metcalf and Gaudet families. It expects to build six barges by year’s end, with the renovation to the Tallulah facility expected to start by mid-September.

LeTourneau Technologies began in Vicksburg as a munitions plant in 1944 and began building jackup rigs after World War II. Rowan had owned LeTourneau since 1994.