By Christina Hager

BOSTON (CBS) – Torre Mastroianni can’t forget that chilly morning weeks ago, when a service technician opened the cap on the tank for his home heating oil. “I looked inside, and that’s when I noticed this really thick, what looked like bacon grease,” said Mastroianni. The boiler had seized up, making the house go cold. “Basically what’s happening is, it’s having a hard time pulling the oil in because it’s so thick,” said Mastroianni.

Peterson Oil, a Worcester based company, had just filled the tank. It’s a company the WBZ-TV I-Team has followed for years. When dozens of customers came forward with similar complaints in 2019, the I-Team took fuel samples to a lab. A former Peterson employee had collected them from broken down systems. Tests turned up more than 80 percent biofuel. Industry experts recommend no more than 20 percent in blends, since too much can cause problems like Mastroianni had. “Especially during a pandemic, people have a lot of stuff going on and it’s just unbelievable,” he said.

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“The law was really clear about, you know, you can’t lie about the level of biodiesel in the fuel you’re selling, and this company did,” said Massachusetts Attorney General Maura Healey. She recently won a $450,000 settlement with Peterson for filling tanks with bad blends at the office buildings of 14 different state and town agencies, including MassDOT and State Police. “It’s just a message to companies out there: make sure you’re good to your word,” said Healey.

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After the I-Team’s first report on Peterson, state regulators ordered the company to be up-front about biofuel. Mastroianni’s receipt said 45-85%, but it was fine print he never even knew about or thought to look for. “I wanted to do this, so that other people will be made aware. Make sure you’re checking your bills. Make sure you know what type of oil that they’re delivering to you,” he said.

We asked owner Howard Peterson for a response to these latest complaints. Despite having talked in the past, this time, he had no response.

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Since the I-Team’s 2019 report, the State Attorney General’s office has received nine more complaints from homeowners about Peterson. A spokesperson says the office has helped many get refunds and repairs. The Better Business Bureau has dropped its accreditation of Peterson, while it’s under review.

Christina Hager