EVERETT — A war of words over how long to extend Snohomish County’s $20-million-per-year solid-waste contract has grown increasingly strident.

The County Council and County Executive Aaron Reardon have been at odds over whether to extend the contract by two or four years. That debate has raged on for months, as county leaders prepare to open the job to competing bids.

Reardon fired off a letter Friday accusing the County Council of creating delays that “have the appearance of protecting the profits of a county vendor over the financial burden placed on county residents.”

“The reasons given for these delays are as numerous as they are illegitimate — and give rise to serious concerns about the Council’s intent in this matter,” Reardon wrote.

The executive’s rhetorical escalation erupted two days after he escaped the threat of criminal charges hanging over him since last fall. Island County Prosecutor Greg Banks announced Wednesday that there was insufficient evidence to charge Reardon over allegations that the married county executive spent taxpayer money on an affair with a female county employee during out-of-state business trips.

The Reardon investigation created an ongoing distraction as county leaders attempted to solve important issues, such as a shortfall in next year’s budget and the solid-waste contract.

Figuring out how to dispose of 400,000 tons of garbage every year is one of the biggest duties of county government.

For more than 20 years, the county has contracted to send garbage by rail to an Eastern Washington landfill. That contract with Allied Waste Services is due to expire next May.

Reardon’s office and all five members of the County Council agree that the county should open up the contract to competing companies.

Allied’s chief competitor, Waste Management, has shown keen interest in the work.

Several council members said they have been forced to extend the waste contract because the executive’s office failed to do its job. Instead of starting to prepare years ago, council members have said, Reardon’s office attempted to rush things last year. Better to wait a few more years, their reasoning goes, than to hastily prepare a contract that could be worth almost a half billion dollars over two decades.

The county council earlier this month instructed Reardon’s office to work on a four-year extension of the Allied Waste Services contract, with an optional extra year. In return, the county expects to receive a 2.5 percent price cut in what it pays Allied per ton of garbage shipped.

County Council Chairman Brian Sullivan said he expected to schedule a council vote on the extension by the end of the month.

The executive’s office has urged an extension of no more than two years, citing the need to look to the marketplace for better, cheaper service.

With the longer contract, Allied Waste stands to gain $100 million in county business. Allied is part of Phoenix-based Republic Services.

A spokeswoman for Allied’s rival, Houston-based Waste Management, has said the extension of any more than two years gives its competitor an unfair advantage. That’s the same position Reardon is taking.

On Monday, Deputy Executive Gary Haakenson called the contract extension, “fiscally irresponsible and frankly, legally questionable.”

“At each step in our process, the Council has added further delays and seems to be intent on extending the contract for the current vendor,” Haakenson wrote in an email.

The letter Reardon sent Friday responded in part to a letter Sullivan sent him earlier that day.

Sullivan questioned Reardon’s assertion that the county could save at least $2 million per year by opening the long-haul contract sooner to competing bids.

“Given that the outcome of a competitive procurement process cannot be known until it has actually occurred, your claim is less a statement of fact than a hopeful supposition,” Sullivan’s letter says.

Reardon had cited examples of jurisdictions that pay less per ton to export waste, including Seattle, Kitsap County and Lewis County. Sullivan said those contracts are not exact comparisons and that there are other jurisdictions that pay more than Snohomish County’s rate of about $50 per ton.

The leaders also clashed over scheduling. Sullivan said Reardon’s timeline failed to account for holiday periods or time for the council to deliberate. Reardon said that critique “borders on the absurd.”

“The people of this County expect their leaders to look out for their interests — even if that means multi-tasking or rescheduling the occasional vacation,” Reardon wrote.

The Reardon investigation turned up evidence that the executive regularly spent time at work talking, sometimes for hours, with the woman who claimed they had an affair. She also told reporters about meeting with Reardon for sex during work hours.

Meanwhile, the state Public Disclosure Commission is investigating evidence that Reardon dialed for dollars and made hundreds of other campaign-related calls on his county-issued cellphone. That often happened when his schedule said he was in staff meetings.

Sullivan, on Monday, said the council’s intent isn’t to fight with Reardon, but to be methodical.

“Multi-tasking on such a big issue is probably not what we need to do,” he said.

The county’s garbage system sends trash by train to a landfill in Roosevelt, in Klickitat County. County workers compress trash into bales at the county’s transfer stations, then truck the material to a north Everett rail yard. There, Allied Waste employees load the material onto trains.

Noah Haglund: 425-339-3465, nhaglund@heraldnet.com.