As a Caltrans highway paving project progresses, temporary reflector markers are adhered to the newly laid asphalt to identify the lanes.

It is a common and accepted practice to use a black, tar-like adhesive substance to paste those reflectors onto the pavement.

But as at least a half-dozen Sonora-area drivers have attested to over the past two days, adhesive material wasn’t used this time. Inch-long metal tacks that attach the markers to the road were used instead and have punctured several tires.

In a prepared statement, Caltrans District 10 Public Information Officer Rick Estrada said, “Caltrans regrets to say that nails were being used to attach temporary reflectors to the highway on a paving project conducted on State Route 49 and State Route 108.”

The standard process on the plastic L-shaped pieces, he said, is to use only the adhesive backing so that drivers can pass safely through the delineated lanes when new paint markers have not yet been applied to the asphalt.

Barry Bishop, of Sonora, said he was exiting Highway 108 in the area of Campo Seco off of Lime Kiln Road, heading back home with his wife on Saturday night, when he heard an intermittent “flapping” coming from one of his front wheels.

“We pulled over after hearing the flap and saw the nail,” he said, adding that he decided to drive directly home because he was so close.

On Tuesday, Bishop had the tire patched at Wright’s Tire in Sonora, but it was the potential safety implications for other Sonora-area drivers that has kept him worried.

“The bad part about it was that it was a busy weekend, a three-day holiday,” he said. “Someone could have had a blowout and a wreck or gotten themselves killed.”

“It was really bad. I didn't think they should be using it,” he said. “I was hoping no one else got hurt and no one got hurt period. I do hope they got to the bottom of that and find out who did it.”

No additional paving will be done on the project until Sunday night, Estrada said. Only adhesive will be used going forward, he added.

Estrada said the approximately nine-mile paving project is being done along three different stretches of highway, from the Highway 49 junction with Chicken Ranch Road in Jamestown to the junction of highway 49 and 108 (3.7 miles); the Highway 108 junction to Peaceful Oak Road (4.4 miles); and just east of Mono Way to just east of Draper Mine Road on Highway 108 (less than one mile) and has been contracted out to Sacramento-based Teichert Construction for night work.

The paving project began in early August and was expected to wrap-up in the fall, Estrada said.

Teichert Construction spokesperson Clark Hulbert acknowledged the use of tacks on the plastic “floppies” on the paving, but noted that they were used on “roughly about half the project” in places where they could be secured to the “area’s ground surface.”

There are multiple Highway 108 overpass areas in the Sonora area that are a part of the paving project – Highway 108’s intersection with Highway 49, and the Highway 108 crossings of Mono Way, Hess Avenue and Peaceful Oak Road.

The tacks were used, Hulbert said, because of the unreliability of the temporary adhesive on a ground surface after conventional grinding equipment leaves dust, residue and gravel on the roadway.

“The adhesive might have a tendency to come up during traffic or conditions or lose the adhesiveness that you'd want,” he said.

As a part of Teichert’s contract with Caltrans, the company is required to grind off a portion of the existing asphalt prior to the future overlay. When the existing delineation is removed, he said, the company is required to replace the lines with a temporary solution: the “floppies,” secured by adhesive or tacks, or a painted line striping, which he said was “not as reflective” and did not provide “surface texture.”

“There's pros and cons to either application,” he said. “The danger is when you don't have centerline or edge-line delineation, that presents a whole other issue.”

Calling the use of the tacks “not uncommon,” Hulbert said that the decision would have been made by a project manager, delegating a “field decision based on the conditions of the road, the amount of traffic and the application. It's a series of circumstances.”

Hulbert said that the tacks and “floppies” will be removed beginning with the Monday night shift, and the delineations will be replaced with the temporary striping.

“The safety of the traveling public is a primary concern of ours,” he said. “We apologize for any inconvenience. It is certainly not our intention.”

Estrada said that motorists who believe their vehicles suffered damage as a result of the tacks can file a claim through the Caltrans damage claim page.

Hulbert confirmed that, according to their contract with Caltrans, they would be responsible for the damages.

“If we are responsible, we will take care of it,” he said.

Jon Wright of Wright’s Tire confirmed that he has patched at least five cars punctured by the nails and temporary markers since Tuesday, and has personally pulled a nail out out of one of the wheels. None of the tires he worked on, he said, required a complete replacement.

“When people drove over them they would bust loose, and when someone ran over it it would puncture the tire,” he said.

Most of his customers were not angry, he added, but said to him, “it doesn't make sense on the highway.”

The Sonora-area California Highway Patrol investigated a report made by a caller at 3:11 p.m. Tuesday about the highway hazards that were reportedly popping vehicle tires at the intersection of Highway 108 and Wigwam Road, CHP Public Information Officer Faustino Pulido said.

A responding unit drove the area but was not able to locate any nails sticking up through the asphalt, he said.

Pulido said Thursday morning that was the only report of the traffic hazards that the CHP has received since Tuesday.

Contact Giuseppe Ricapito at (209) 588-4526 or . Follow him on Twitter @gsepinsonora.