It all began shortly after 4 a.m. Oct. 23, when a tractor-trailer driver with a cargo of more than 1,500 gallon containers of antifreeze pulled over to the shoulder of Interstate 78, at the Summit Lawn exit, atop South Mountain, to try and put out a small brake system fire.

With only small hand fire extinguishers, that firefighting effort didn’t turn out well and the trailer was quickly enveloped in flames.

The Lehigh County 911 Center dispatched Eastern and Western Salisbury fire departments 4:40 a.m. Tuesday morning. Western Salisbury Fire Chief Joshua Wells was first on the scene and reported the rear of the trailer was “fully involved” in flames.

Tankers from Eastern Salisbury Fire Department and Upper Saucon and Woodlawn fire departments were dispatched to supplement Eastern and Western Salisbury’s fire engine water supply.

Engines from Eastern and Western arrived almost simultaneously, and firefighters from both companies attacked and quickly knocked down the flames. After extinguishing flames in debris and foliage along the sound barrier abutting the shoulder of the interstate, firefighters noticed fluid leaking from the rear of the trailer.

The trailer had become unbalanced when the driver pulled the tractor away from the flames, and the rear portion was tilted to the ground. Antifreeze was leaking from the trailer and headed for a nearby stormwater drain that emptied into a creek along Lanze Lane, which runs paralleled to the interstate, on the western side of the concrete sound barrier.

Salisbury firefighters deployed absorbent booms in an attempt to staunch the flow.

By mid-morning, residents along the Lanze Lane neighborhood were calling the county communications center reporting a tributary creek leading to the Little Lehigh was flowing green, After Wells went to investigate and confirm the spill into the creek, he immediately contacted the 911 center to request a full hazmat response from the Lehigh County Special Operations Team. That team is the initial responder for all Lehigh County hazmat incidents.

By noon, Salisbury Township police, township road crews, Allentown hazmat teams, Lehigh County, Pennsylvania Department of Environmental Protection and fishery department crews were involved, and a daylong hazardous material incident response was underway.

Rapid Response, an environmental cleanup contractor from Northampton, was called in to unload the remaining trailer cargo for disposal and to set up a mitigation crew at the base of South Mountain, to intercept the downhill flow.

The creek was dammed behind the Camelot House facility along Emaus Avenue, near the interstate road, Tuesday afternoon, and two mobile 21,000-gallon tanks were brought in to vacuum contaminated water from the creek in an overnight operation.

Eastern Salisbury Fire Department’s tanker truck, at dusk Tuesday, flowed 3,000 gallons of water into the Lanze Lane creek as a water marker to let Emaus Avenue crews know when the creek was flushed. The small tributary eventually empties into the Little Lehigh, so the pumping station was the incident’s last stand.

By Wednesday morning the creek was flowing clean and the operation was terminated – except for the inevitable paperwork that always follows.