A $48-million contract awarded March 23 to AECOM to study impacts of widening 34 miles of the most rural southern part of the 117.2-mile New Jersey Turnpike has upset state environmental activists who say the project conflicts with the state's push to combat climate change; officials say construction remains at least five years off.

The contract is the latest step in the overall $1.1-billion turnpike expansion plan outlined last year that focuses on addin a third lane in each direction to the section stretch between exits 1 and  4 through Camden County. But it also renewed criticism from advocates who say the project will boost greenhouse-gas emissions at a time when the state is investing heavily in cleaner energy and other strategies to reduce them.

AECOM, which did not respond to a request for comment, was chosen to do preliminary work on the widening, among 14 projects under the $24-billion capital program..

Transportation officials say public hearings have yet to be scheduled. Tom Feeney, a spokesman for the NJ Turnpike Authority, says it’s too early to tell whether adding a new lane in each direction would increase emissions, with impacts needing to be studied.

Also on the drawing board is a plan to double lanes from two to four in both directions on a three-mile turnpike section crossing Newark Bay closer to New York City, which would involve replacement or widening of three bridges and construction of a fourth bridge, estimated to cost $3.3 billion.

The new turnpike project would follow a $2.3-billion expansion completed several years ago along the 35-mile interchange 6 to 9 corridor.

The authority also wants to add one lane in both directions to 27 miles of the Garden State Parkway between interchanges 98 and 125 at a cost of $1.35 billion. Another planned project would widen 12 parkway miles from interchanges 142 to 154 from four lanes to six in each direction, estimated at $2.5 billion.

While the plan claims to ease traffic congestion, environmentalists say it doesn’t mesh with Democratic Gov. Phil Murphy’s Energy Master Plan.

Jeff Tittel, director of the New Jersey Sierra Club, says the turnpike in south Jersey should not  be widened because it would increase traffic and create even more lengthy southbound backups leading to the Delaware Memorial Bridge in Salem County.

“Once you widen the highways, it’s a temporary fix until there’s more traffic. And there’s going to be more traffic," he said., noting the convergence of two other arteries feeding into the bridge crossing to Delaware.

Tittel said he favors more focus on light rail and electric buses. “At end of the day, they are just adding and widening, so the other concern is that we are going to accelerate farmlands to warehouses, create sprawl and add more trucks," he said.

Also, in Camden County, the New Jersey Dept. of Transportation began investigating the March 25 collapse of a newly built retaining wall on north-south I-295 that is part of the $900-million Direct Connection project to straighten out a convoluted interchange with east-west Route 42 and Interstate-76 between Philadelphia and Atlantic  City. The project is set for completion in 2027.

The collapse occurred on a stretch of I-295 still under construction, with one lane remaining closed, and the wall set for demolition. The cause still is unknown.