That light you see isn’t at the end of the tunnel. It’s at the far side of the Peace Bridge as trucks bound for the United States line up to be inspected by U.S. customs officers in Fort Erie, Ont. The deal, to hear Sen. Charles E. Schumer tell it, is all but done and it will have tremendous ramifications for Buffalo and the region.

The plan, which still requires formal approval, would move truck inspections to Fort Erie as part of an 18-month experiment that will also be conducted at another crossing, likely in Washington State. The goal is to expedite traffic, trade and tourism between the United States and Canada, with no adverse impact on security. If the experiment succeeds, it will become permanent.

But the program, if successful, will do more than improve trade and tourism. It will have a significant positive effect on Buffalo and, in particular, the West Side neighborhood near the Peace Bridge plaza.

Much of the controversy surrounding plans to expand the customs plaza centers on the health risks posed by truck exhaust. Almost exclusively, the problem is with idling trucks that are frequently backed up across the bridge awaiting inspection. Health problems, including high incidences of asthma, have been reported in the area.

The state Department of Environmental Conservation has launched a program to monitor air quality around the plaza, which was a good first step in determining the scope of the problem, but wasn’t, on its own, a solution. Moving truck inspections to Fort Erie, where there is more room and the population is smaller, is a solution.

Eliminating the trucks lined up at Buffalo inspection booths would also allow more design options for the customs plaza, which is due to be expanded.

If the experiment gets the go-ahead, some work can begin on the plaza, said Ron Rienas, general manager of the Bridge Authority. Construction of a secondary inspection plaza for commercial traffic could begin, as could widening of the bridge approach and issues relating to traffic leaving the plaza. Design and construction of inspection booths themselves would await the conclusion of the 18-month pilot program.

The idea of inspecting U.S.-bound traffic in Ontario has been proposed for years but always hung up on the issue of whether U.S. customs and border agents could carry guns while performing their duties in Canada. Indeed, U.S. Homeland Security Secretary Janet Napolitano previously pronounced the idea dead. “It cannot be done,” she said.

But with the diligence of leaders, including Schumer, Rep. Brian Higgins and Gov. Andrew M. Cuomo, a way was found to make it work, although details have yet to be worked out. One option is to allow U.S. law enforcement officers to carry guns on Canadian soil but be subject to stringent Canadian laws and regulations. That prospect could run into turbulence with the officers’ union.

Another would allow armed Canadian law enforcement personnel to accompany U.S. officers during inspections in Fort Erie, much the same as they already do at major Canadian airports where travelers are pre-cleared before arrival in this country.

In addition to settling the weapons issue – which Napolitano now believes will be resolved – the deal is contingent upon the United States and Canada hammering out a bilateral memorandum of understanding that includes issues beyond the pilot program. That agreement is expected to be concluded soon, said Homeland Security spokesman Peter Boogaard.

This is a hopeful moment for those who want to see a new plaza and Peace Bridge constructed here and for those whose health is assaulted by fumes from scores of idling trucks. It looks like a win for all concerned.

Here’s hoping nobody messes it up.