It’s hard to argue against clean air.

There was a time when the L.A. urban area had little of it, and it was only through the efforts of public officials using strict regulations and cleaner technologies that the smog was, in large part, lifted.

It also can be hard to balance economic development and environmental priorities when one of the area’s biggest polluters is one of its greatest economic engines. That’s the case with the ports of Long Beach and Los Angeles, although both deserve credit for drastically reducing their pollution levels over the past decade, particularly that of unhealthy diesel particulate matter, which has been cut by more than 80 percent.

Now port officials are ready to roll out an update to their Clean Air Action Plan (see page 1), with the ambitious goal of having nothing but zero-emission vehicles and cargo-handling equipment in use at the nation’s busiest port complex by 2035.

It’s an apt time for them to also update their understanding of the real-world business impacts of the plan.

Port officials have estimated the cost of implementation at up to $14 billion – a price tag to be paid by both public funding and private industry, though how exactly that will be divied up, what the funding sources will be and even what technology will be used remain unclear.

Such uncertainty understandably can make local trucking companies and the 12,000 tractor-trailer drivers who play an essential role in moving about $450 billion worth of cargo to and from the ports each year a bit nervous.

That’s not surprising given the truckers’ experience when the ports launched their

signature Clean Trucks Program in 2008.

That effort, though it paid off on air quality

in the long run, encountered some serious speed bumps, with trucking companies and drivers complaining that the new low-emission vehicles often spent more time in repair than at work.

On top of this is the workforce model used by most local trucking companies that categorizes drivers as independent contractors, not employees. A vocal group of drivers, backed by the Teamsters, have been fighting this, saying that for all intents and purposes, they are employees.

Whether that’s true – in many cases it has been, as far as the California Labor Commission is concerned – few dispute that much of the cost of operating and maintaining tractor-trailers has been passed on to these drivers. When new clean-air rules and equipment mandates roll out, that creates an added burden.