Story highlights Former workers at a California slaughterhouse have been indicted

They are accused of distributing "adulterated, misbranded, and uninspected" meat

Prosecutors allege that the workers processed cows with signs of "cancer eye"

Authorities recalled nearly 9 million pounds of meat from the slaughterhouse in February

Former workers at a California slaughterhouse involved in one of the largest meat recalls in years have been charged with knowingly processing and distributing meat from cancerous cows, according to court documents released Monday.

Jesse J. Amaral Jr., also known as "Babe Amaral," was the former President and General Manager of the Rancho Feeding Corporation in Petaluma. He and his former employees, Felix Sandoval Cabrera and Eugene Corda, have all been charged with conspiring to sell and distribute "adulterated, misbranded, and uninspected" meat.

Prosecutors allege that Amaral directed Corda and Cabrera to circumvent inspection procedures for certain cows with signs of epithelioma of the eye, also known as "cancer eye."

This included directing employees to carve "USDA Condemned" stamps out of certain cow carcasses and to process them for sale and distribution, despite having been rejected by the U.S. Department of Agriculture veterinarian.

Corda and Cabrera are also alleged to have replaced the heads of sick cows with those of healthy ones, placing the healthy heads next to the bodies of cows whose eyes had signs of cancer. The switch occurred during the inspectors' lunch break, prosecutors said.

Massive recall

Between January 2013 and January 2014, Rancho processed and distributed meat from approximately 101 condemned cattle and approximately 79 cancer eye cows, according to court documents.

Nearly 9 million pounds of meat from the Rancho plant was recalled in February. The recalled beef may have reached 35 states and Guam , the Department of Agriculture said.

Nestle USA also issued a voluntary recall in February of some types of Hot Pockets, saying that it had determined that "a small quantity of meat from Rancho was used at Nestle's Chatsworth, California, production operation," which is devoted entirely to Hot Pockets sandwiches.

Maximum sentence of 20 years

Amaral is also charged with sending false invoices to farmers, telling them that their cattle had died or been condemned and charging them "handling fees" for disposal of the carcasses, instead of compensating them for the sale price, prosecutors said.

If convicted, Amaral, Cabrera, and Corda could face up to 20 years imprisonment and $250,000 in fines.

CNN's attempts to reach the former workers and an attorney representing them were unsuccessful.

An attorney for Amaral, Jeffrey Borstein, told CNN in May that his client didn't intend to hurt anyone.

"He takes responsibility for mistakes in judgment that were made. He made mistakes in judgment," Bornstein said. "He regrets not being better able to recognize, respond and stop some of these alleged bad practices earlier. He's extremely remorseful."

USDA investigation

Cabrera was a foreman responsible for Rancho's "kill floor," where cattle were slaughtered, and Corda worked to receive and transport cattle for inspection and slaughter.

The plant has since been sold.