State transportation officials abruptly reversed themselves on Friday and reinstituted a ban on a controversial asphalt additive after initial tests on samples from newly paved roads showed the material falls apart long before it is supposed to, a flaw that could potentially cost taxpayers millions of dollars to redo streets and highways.

The announcement of the ban on the use of recycled engine oil as a binder in asphalt came Thursday afternoon at the end of a two-day conference of state transportation officials and industry representatives in Framingham. The conference included tense confrontations between state engineers from around the Northeast and asphalt makers over the use of the unproven product that manufacturers had been blending in for years without telling anyone.  

The decision also comes after CommonWealth reported in recent Fall issue that administrators at the Massachusetts Department of Transportation had overruled concerns by their own engineers, who had pushed for a ban until testing could be done. State Highway  Administrator Frank DePaola, who will become interim transportation secretary next month, had said he thought the move by his engineers was “arbitrary” and placed an undue burden on producers. 

State Highway Administrator Frank DePaola

But on Thursday, MassDOT officials reversed course and issued a full moratorium in a letter to industry officials after apparently being convinced by those same engineers, who showed results from samples they had taken off recently paved state projects lacked the adhesion of normal asphalt and was apparently leeching toxic oil into surrounding land and groundwater around the roads. Neither DePaola nor a spokeswoman returned several calls for comment. 

The samples were taken from an ongoing paving project along a stretch of I-93 in Wilimington and Woburn and brought to the state’s materials testing lab at the University of Massachusetts Dartmouth. It was subjected to what is known as the “hamburg wheel test,” where a device rolls over the sample some 20,000 times to determine its suitability for use over the long-term in the harsh New England climate. The testing was stopped a little more than halfway through because the samples were showing a dramatic failure, according to an email obtained by CommonWealth to construction industry officials. 

“The test is meant to measure the rutting and moisture susceptibility of an asphalt paving mixture by rolling a steel wheel across the surface while it is immersed in water,” Michael McGrath, deputy chief engineer for construction for MassDOT, wrote in the email accompanying the letter announcing the new moratorium. “The testing was stopped after 13,900 cycles due to the deformation of the sample. Based on these test results MassDOT has decided to move ahead with a moratorium on the use” of recycled engine oil in asphalt. 

The use of recycled engine oil bottoms, commonly called REOB, has been going on for decades as a way to reduce costs of asphalt, saving money for state and local highway departments while also increasing profits for asphalt producers by “cutting” expensive virgin asphalt. But until recently, the REOB-infused asphalt was used mainly in warmer climates and when it was introduced up here, asphalt suppliers did not reveal it to users. 

Several New England states as well as Canada began seeing cracks develop in newly paved roads after five to seven years when most paving is supposed to last as long as 20 years or more. It was only after testing in Canada found the recycled engine oil that asphalt makers admitted it was in the product but declined to stop using it, claiming it was safe and effective. 

But tests did not show those same results and this summer, after an emergency “asphalt summit” at UMass Dartmouth, transportation officials from four New England states banned the use of REOB despite pleas from the main producer, Montreal-based Bitumar, and representatives from Clean Harbors in Norwell, which owns Safety-Kleen in Texas, one of the first and largest producers of the recycled engine oil. After the bans were announced, Bitumar sued each state and sought an injunction.  

A Vermont court granted the injunction but judges in Maine and New Hampshire upheld the ban. In Massachusetts, on the eve of a hearing at the end of July, DePaola reversed the ban before it was to take effect, an action so abrupt not even the state lawyer defending MassDOT was aware it had occurred. 

The sudden change of direction once more caught many by surprise, causing a stir at the Northeast Asphalt User Producer Group conference that included representatives from 10 Northeast states’ departments of transportation as well as asphalt and construction officials. Many state engineers had tough questions and pointed remarks for industry officials both about their insistence the product was not the problem as well as the years they went without revealing the recycled engine oil was in the asphalt, delaying any chance to find and rectify the growing issue of failing roadways. 

“For the last seven years, we’ve been noticing a failure phenomenon in Vermont,” Bill Ahearn, an engineer with the DOT there, told a packed committee meeting focusing on the use of REOB as a binder. “We aren’t rowing all in the same direction but we are all in the same boat. I would far rather pay more for my liquid and have a project that lasted. Anybody who is trying to save me money, please don’t. Something has changed and now I have a performance issue.” 

Terry Arnold, senior research chemist with the Federal Highway Administration, told the conference that concerns over recycled engine oil as well as problems with not being made aware to its use are not restricted to the northeast and Canada. Arnold said over the last several years, his office has performed tests on more than 1,200 samples sent in from nearly every state. He said more than a third contained recycled engine oil, many from states that insisted it was not being used including some states such as New York where a ban is in place. “People these days have become a little more cavalier as to what they put in,” said Arnold. 

Several industry-backed analysts offered test results that they say shows recycled oil at low levels, generally less than 10 percent of the total volume of asphalt mix, did not produce the early failures that asphalt with higher concentrations had. But those results were challenged during the question and answer periods by engineers who were cynical about the testing. 

As the conference was breaking up, John Grieco, an engineer with MassDOT who had a number of critical questions and comments for the asphalt makers, announced that the state would ban the use of the product effective immediately. When a representative from one asphalt producer asked if there was any level acceptable for adding the recycled engine oil, Grieco said it was a “zero policy.” 

Immediately after that, an official from Rhode Island said that state would also issue a ban within the next several weeks. But those actions may be too late for a number of roads around Massachusetts where contractors have been putting down tens of thousands of tons of asphalt after the ban was rescinded in July.  

Not only were thousands of tons laid on state highways last year, before the presence of recycled engine oil was known, and in the last several months after MassDOT pulled the planned ban, cities and towns also have the potentially faulty asphalt on their roads. Local public works departments are required to use products that have been approved by the state so even if they had qualms about REOB-enriched asphalt, they had no choice but to use it. And now, if cracks begin to show, they’ll have little choice but to eat the costs for repaving. 

One Massachusetts engineer who did not want to be identified said no one knows how much asphalt with recycled engine oil was used around the state or even where it is. He said if asphalt producers can convince officials to allow them to use a small percentage of recycled engine oil, that could trigger even more problems. 

“We will be watching it,” said the engineer. “It’s unknown how much is down [on state roads]. But the cracking properties are noticeable. Even using a small amount, isn’t that kind of delaying the inevitable?”