Multiple rounds of negotiation apparently followed. JBS said it had trained employees “to look for and to determine signs of distress” and had committed to performing a “daily animal welfare audit.” After months of negotiation, FSIS finally noted in the October 19 letter that it was satisfied with improvements and would rescind the notice. But the letter ended with words of admonishment that, considering the recent recall, would prove to be prophetic.

“You are reminded that as an operator of a federally inspected facility, you are expected to comply with the Federal Meat Inspection Act (FMIA) and the regulations promulgated thereunder to ensure that livestock at your establishment are handled and slaughtered humanely,” Yudhbir Sharma, the director of FSIS’s Alameda, California office noted.

He went on: “It is also important for you to understand that FSIS has the responsibility to initiate actions if your establishment fails to operate in accordance with FSIS regulations, or conditions occur that may render products unwholesome or adulterated.”

Now, less than a year later, we know that conditions did occur at Tolleson to “render products unwholesome or adulterated.” Almost 7 million pounds of ground beef suspected to be tainted with Salmonella Newport were recalled, meaning that the meat of nearly 13,000 cattle will ultimately end up in landfill. FSIS has not been willing to provide additional details on what led to the outbreak, and JBS has not responded to repeated requests for comment. But the scenario I laid out earlier this week starts to look even more likely.

I’ve already made my speculative case that dairy cows are to blame for JBS’s latest recall, the largest recall of ground beef for Salmonella ever. As I reported previously, we already know that dairy cows, which provide about 20 percent of the nation’s ground beef supply, are the likeliest reservoir of Salmonella Newport. We know that dairy cows usually don’t enter the food supply until they get old, weak, or sick. We know that, in processing plants, dairy cow meat is used as filler in ground beef—a practice that exponentially increases its already significant public health risks, and has the potential to contaminate huge volumes of product.

The revelation of the FSIS letters makes an emerging picture even clearer. We now know that sick dairy cattle, so ill they could barely stand, were present at Tolleson just one year before the recall started. We know, too, that FSIS felt JBS employees were unable to identify excessively suffering animals and disarm problems as they happened.

Now, two other questions remain. When will FSIS provide the public with a full account of what happened at Tolleson? And if dairy cows prove to be the culprit, can we have a conversation about how to treat these animals—often sickened or weakened by the demands of high-volume milk production—as we rethink the role they play in feeding us?