CHICAGO (CBS) — A veteran mail carrier is fed up and speaking out – exposing the behind-the-scenes issues affecting mail delivery.

He shared his frustrations with CBS 2 Political Investigator Dana Kozlov, and hopes some of them will finally get fixed.

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Through fall, winter, spring, and now summer, mail delivery issues continue to plague the Chicago area.

“It’s ridiculous how they let this go on,” the postal worker said.

And, he said, it is for reasons most customers don’t even realize.

“Eighteen routes – five people come to work,” he said.

The carrier, who wants to remain anonymous, believes the severe USPS staffing shortage is partially due to the emergency federal employee leave enacted this year – which gives postal workers up to 600 hours of paid leave for COVID-related reasons. That’s right, 600 hours – roughly four months of paid time off if employees qualify.

“There’s rumors that people that’s using that COVID leave don’t need it,” the carrier said.

And that’s not all. The carrier said his supervisor told him package delivery is now a priority over first-class mail.

Kozlov: “That means mail, like the first-class mail, just sits there.”

Carrier: “Sits in the case. It could be a week, two weeks – or it could be on the floor waiting to be cased.”

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Kozlov: “Do you think that’s one reason some people aren’t getting their mail?”

Carrier: “I know that’s the reason.”

He himself is not getting all his mail either.

“We’ve seen little improvement,” said Ald. Matt O’Shea (19th).

O’Shea has been an outspoken critic of mail delivery issues in his ward. He goes out of his way to acknowledge the hardworking carriers.

But O’Shea also said he would not be surprised to learn the 600 hours of leave may be slowing delivery even more.

“For the United States Postal Service to say, ‘We’re going to give everybody 600 hours,’ and not expect that there’s going to be a problem; not expect we’re not going to be able to get the mail out?” O’Shea said. “Once again, and utter failure on their leadership. What was their plan? They had no plan.”

Just last week, Eddie Morgan replaced Wanda Prater as Chicago’s new postmaster. That move was made in part because of the ongoing problems.

O’Shea hopes to speak with Morgan soon, and the anonymous carrier has some questions for Morgan too.

“I hear he’s a no-type-of-nonsense of guy,” the carrier said. “But I would lie to ask him how he’d fix people not coming to work. That’s the number-one thing he needs to fix.”

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Kozlov reached out to the Postal Service to ask if it was investigating any abuse of that 600-hour leave and if they were prioritizing packages over letters. A spokesperson said they were compiling information and would respond later this week.