Large and illicit heaps of discarded tires are reappearing around New Jersey, a state auditor's study has found, and the report is urging a renewed effort to "monitor, identify, and remediate" them.

"Scrap tires are not only an eyesore, but also present an environmental and public-health threat," State Auditor Stephen Eells wrote in an Aug. 22 memo to Gov. Christie and legislative leaders.

Eells' office found that the colossal mountains of abandoned tires that once dotted the landscape were now gone, with "the vast majority" of used tires ultimately recycled.

But, he noted, a Department of Environmental Protection survey this year found that 18 of 26 major scrap-tire-pile sites "did not comply with state regulations" and needed remediation.

Eells' report also posed the question of whether the executive branch should restore to the Department of Environmental Protection some of the millions of dollars the state collects annually from a new-tire fee once earmarked for improved tire disposal.

"I'm not saying DEP is doing anything wrong," Eells said last week in an interview. "What I'm telling the Legislature is that I'm not comfortable with something I've observed."

Twelve years ago, the state was home to an estimated 3.2 million discarded tires, according to DEP data, with some of those in dumps containing hundreds of thousands of tires and one with nearly a million.

Whether the estimated 560,000 tires now in dumps and recycling centers - some of them exposed - pose a major hazard or a minor nuisance is a matter of debate.

"Once ignited, scrap tires are notoriously difficult to extinguish," Eells said in his report, and they can produce "dense, noxious smoke" and an oily residue that contaminates groundwater.

Exposed tires also capture rainwater, Eells said, which can become a breeding habitat for mosquitoes carrying encephalitis and possibly Zika virus.

But Ray Bukowski, assistant DEP commissioner and head of its Bureau of Solid Waste Compliance and Enforcement, said last week that discarded tires, while "always on our radar" were "no more important than the other recycled or waste sectors we monitor."

"Most of the actors [site operators] nowadays are appropriate," Bukowski said, and the state had "made significant progress from the old days of tire mountains."

In a response to the auditor's report, DEP Commissioner Bob Martin wrote that he agreed that the department should "develop a process to periodically identify illegal scrap piles" in the state and that it had appointed a "case manager/inspector" to review their status.

Martin said the department was also considering whether to require storm-water permits for facilities that store large amounts of tires and whether to provide grants to counties to monitor tire dumps and recycling facilities. It is also planning flights over the state this fall to find unknown and illegal dumps.

Eells last week described Martin's letter as a "positive response. We're pretty happy with it."

The state Auditor's Office monitors the work of the executive branch on behalf of the Legislature, to which it reports. The auditor is appointed to a five-year term within the nonpartisan Office of Legislative Services. Eells is in his sixth year.

The tire audit began, he said, when one of his inspectors recently bought new tires and saw that the purchase included a $1.50 state fee for the disposal of old tires.

"He got to wondering how that was working," Eells said, and suggested a study.

The report noted that the Legislature had enacted the tire fee in 2004 as part of a comprehensive effort to drastically reduce the dumped-tire problem.

With revenue from the fee projected at $12.4 million, $2.3 million was earmarked for the DEP for that purpose, with the rest going to the Department of Transportation for snow removal.

After the first year, however, all of the tire-fee revenue has gone to snow removal.

Bukowski said his bureau had become so accustomed to not receiving funds from the new tire fee that he did not foresee petitioning the executive branch to restore it.

"We could always use more funds and more people," he said, but with just 38 tire dumps around the state, the staff inspecting recycling services is sufficient.

"We've lived without it for a long time," he said of the tire-fee revenue. "And snow removal is a pretty important safety issue."