Mayor Rahm Emanuel’s administration has allowed a private city recycling hauler to divert tons of plastics and paper from residences to landfills the company owns, costing taxpayers twice and adding to Chicago’s worst-in-the-nation recycling rate.

As a result, residents of the Northwest Side and Far South Side — areas where Texas-based Waste Management holds city recycling contracts — are far more likely to have the plastic, glass and metals they put out to be recycled instead end up in a garbage dump than other Chicagoans.

Under city rules, one plastic bag or food item improperly placed in a recycling bin could mean the whole bin is labeled “grossly contaminated” with improper items and its contents taken to a landfill.

Waste Management is the only city of Chicago recycling hauler that also operates a for-profit landfill — where roughly 15 percent of the city’s garbage is dumped.

That means the company — which gets recycling fees from City Hall whether its crews pick up a bin or tag it as contaminated — is again paid when the tagged bins are taken by city trash crews to its landfill, an investigation by the Better Government Association found.

Since 2014, private and city waste-hauling crews have labeled at least 577,886 recycling bins as “grossly contaminated,” records show. Of those, 514,239 — nearly 90 percent — were tagged by Waste Management, whose green trucks cover only half of the city.

That would be enough blue bins to fill Wrigley Field from the playing surface to beyond the top of its iconic scoreboard.

Waste Management officials declined to be interviewed. In emailed responses to questions, the company denied any financial motive behind the numbers.

“The overall premise of your story that we are purposely trying to divert materials to landfills is not true,” company spokeswoman Lisa Disbrow said. “Recycling contamination is an undeniable trend across the country. It is no different here in Chicago.”

The company also said the city — not Waste Management — decides where to dump contaminated bins.

“What’s the point in recycling if they’re not even going to pick it up?” said Peter Bencak, 67, a Wicker Park resident whose blue bins have been tagged as contaminated seven times since late 2015. “My cans are never contaminated.”

Bencak said he’s diligent about cleaning and sorting his recycling and called to complain to Waste Management. “I said, ‘Listen, you’re calling me a liar, and I’m telling you I’m not contaminated, and I’ve never been contaminated. So if you’re telling me I am, then your man is lying to you.’ ”

Linda McKillop, 71, whose Portage Park recycling bin was tagged once in 2016, said she called the city to explain how carefully she sorts her recycling. “I was so aggravated, and I could not get over it. I really think the city of Chicago is being ripped off with how they’re handling recycling.”

With fanfare, Emanuel in 2011 announced a competition to pick the best recycling contractor and finally expand recycling to every home.

But the city’s residential recycling rate has declined since 2013 and now is just 9 percent — by far the lowest of any major city. Houston is second lowest at 17 percent.

“It’s probably one of the most poorly run programs in the city,” said Ald. Scott Waguespack (32nd), an Emanuel critic. “No one has seen anything out of this managed competition on a year-to-year basis to see if they’re in compliance, if we are getting the lowest cost for our services or getting the actual recycling done.”

Emanuel aides defend his Blue Cart initiative, saying managed competition has saved taxpayers $10 million a year and that the Department of Streets and Sanitation continues to “closely monitor” the program.

City officials say the amount of contaminated recycling from bins pales compared to the more than half-million tons of recyclable waste diverted from landfills since 2011. They also say the city recently renewed efforts to improve contamination labels and educate people on what to recycle.

Under the program, the city carved out six zones for recycling pickups, with three going to Waste Management and another to SIMS Metal Management, which subcontracts collection work to Lakeshore Recycling Systems. City sanitation crews cover the other two zones.

MORE FROM THE WATCHDOGS

Emanuel promised to evaluate the competition within six months. That still hasn’t happened after six years. Records show the program has run largely on autopilot, with no declared winner of the “managed competition” and no comprehensive assessment. Still, both private haulers got a one-year contract extension from City Hall this year.

The Emanuel administration hasn’t collected data it would need to determine which hauler did the job best and cheapest.

By contract, the private haulers are required to file monthly reports with the city detailing where recycling is taken, how much contaminated material in Blue Cart bins must be sorted out at recycling centers and how much taxpayer money is going to subcontractors.

Streets and Sanitation officials acknowledge that the department hasn’t gotten most of the mandatory reports.

The city doesn’t track the landfill destination of contaminated recycling bins. So it’s impossible to determine how much went to Waste Management’s dump. City officials acknowledge the company’s landfill gets some of the material.

If the contents of contaminated bins are going to Waste Management’s landfill at the same rate as city garbage, that would mean about 5,000 tons of recyclables have been diverted to the company’s dump.

City officials said they don’t know why Waste Management tags so many more bins as contaminated. They said it might be because the company has a more aggressive education campaign — an assertion its competitor Lakeshore disputes.

In the residential program, the haulers have discretion to decide when recycling bins are contaminated. Those bins are tagged and left for city crews to take to garbage dumps.

Chicago is the only major city that gives private haulers sole discretion to decide which recycling gets diverted to landfills. Many other cities use only municipal collection crews.

Chris Sauve, the top Streets and Sanitation department official in charge of the recycling program, said his office has never looked into why Waste Management accounts for the vast bulk of contaminated bins even though it is assigned to pick up only half the city’s blue bins.

“Should measures be put in place to double-check to make sure that the tags put out by the Waste Management crew are accurate? Yes,” said Sauve, a deputy commissioner.

In addition to being paid under city contract to pick up each recycling bin, the private recycling haulers can sell recycled material on the open market, which has faced plummeting prices in the past couple of years, according to Waste Management officials. That dip in prices has coincided with a surge in contamination tags the company’s haulers have issued.“There’s a financial incentive for them to say, ‘You know what? Let’s not pick this stuff up,’ ” Ald. John Arena (45th), complained at a City Council budget hearing last year.

Madison Hopkins reports for the Better Government Association.