Puerto Rico's power authority is reportedly carrying out mismanagements, with consumers receiving the worst blow.

During Abraham Ortiz's time as a lab director at the island's power authority PREPA, he found that officials in the purchasing department controlled contracts to buy oil worth billions of dollars, according to the New York Times.

Ortiz told his superiors that for years, the authority bought cheap and residual oil that failed to pass federal clean-air standards, and falsified documents to make it appear that the oil was high-grade, the news outlet wrote. In the 1990s, the Environmental Protection Agency discovered that the oil being burned by the authority contained intolerable levels of sulfur, which was toxic to the neighborhoods near the power plants.

Ortiz added that ledgers were also faked by the authority, the New York Times added. With this, the power utility made it appear that they purchased higher-quality oil, which was more money. The higher cost was then shouldered by consumers.

After he discovered the authority's mismanagements 25 years ago, Ortiz was transferred to another department -- one where he would not handle oil testing, the New York Times noted. Now, however, a committee of the Puerto Rico Senate is investigating the utility's purchasing department, the Fuel Procurement Office. Ortiz, who is now retired, is a star witness.

Eduardo Bhatia, the Senate president overseeing the hearings, said that the issue is "a criminal matter," the news outlet further reported. He said that the utility's long-standing duty is to provide development and affluence on Puerto Rico, but instead, it has failed the island.

According to Bhatia, the government began suspecting PREPA of mishandling finances when it had borrowed millions of dollars for construction projects, which weren't built at all, the New York Times noted.

On Monday, Puerto Rico's House of Representatives approved a bill to overhaul PREPA, Reuters reported. Resolving the power utility's debt is one of the steps required to fix the island's overall $70 million debt.

The Senate will determine how the power utility became swamped with more than $8 billion in debt that it is unable to pay, the New York Times wrote. The legislature has a key deadline scheduled on Tuesday about how the authority plans to renegotiate the debt.

The authority promised -- and failed -- to "use money from the bonds it sold to upgrade its plants and phase out oil as its fuel for generating electricity -- something most power utilities in the United States did years ago," the news outlet noted. Puerto Rico still doesn't see that change.

The utility's financial woes are complex and multilayered. However, the biggest issue is the allegation that it purchased unclean oil while billing consumers for clean oil, the New York Times reported.