Sheriff Rob Coon did not immediately return phone calls Tuesday, but in the past, he has expressed concern about potential trouble at the Roswell plant.
Attempts by companies like Valley Meat Co. to resume domestic horse slaughter have ignited an emotional national debate that has resulted in a string of threats against De Los Santos, his family and his business.
"We have had some say, 'I hope your building burns down,'" De Los Santos said. "That's not good at all. What are they going to do next? Take a pot shot at us when we are walking in?"
On Saturday, De Los Santos said someone apparently jumped the fence, then poured accelerant over the compressors to his refrigeration unit. A passer-by alerted authorities.
"The fire inspector was out there," De Los Santos said. "He took samples of the dirt and stuff just to make sure. But he said this was something that was not done by electricity or lightning. He said something was poured on it to light it."
De Los Santos says the company will be unable to open as planned Monday without a working refrigeration unit.
The company also goes to federal court Friday to fight attempts by The Humane Society of the United States and other groups to block the opening of Valley Meat and another recently approved horse slaughterhouse in Iowa.
The groups contend that the Department of Agriculture failed to conduct the proper environmental reviews before issuing the companies permits to slaughter horses.
The USDA also opposes horse slaughter. But after being sued by Valley Meat Co. for failing to act on its application, the agency said it was obligated to issue the permits since Congress lifted a ban on domestic horse slaughter in 2011.
Meat from the slaughterhouses would be shipped to some countries for human consumption and for use as zoo and other animal food.