The leafy green growing season around Yuma, AZ is about to get underway and there will be one difference from last year. This year, the buffer zone between concentrated animal feeding operations, known as CAFOs, will be tripled, from 400 feet last growing season to 1,200 feet this year.

The greater buffer zones were adopted by both Arizona and California members of the Leafy Greens Marketing Agreements in response to this year’s outbreak of E. coli O157: H7 involving romaine lettuce from the Yuma growing region.

November is the start of the growing season for the Yuma region. The LGMAs managed to get the new rules in place during September, just ahead of October’s task: transition. That’s what they call the move leafy green growers and processors make twice a year between Salinas, CA and Yuma, AZ.

The transition is a mammoth undertaking involving hundreds of trucks to move all the agricultural equipment. And there’s a suspicion transition makes equipment for susceptible to transmitting foodborne diseases.

Almost 95 percent of leafy greens grown in the United States come out of the Yuma and Salinas growing regions. This year’s E. coli O157: H7 outbreak, which sickened 210 people in 36 states, resulting in five deaths, was the most serious threat for the Arizona and California growers since the 2006 E. coli outbreak involving bagged spinach.

The fresh spinach outbreak, which sickened 199 people in 26 states, causing three deaths, led to a widespread loss of consumer confidence in the U.S. to bagged spinach and lettuce products. Retailers demanded action from growers to get it back. Fast.

The Leafy Green Marketing Agreements that resulted involve food safety practices and metrics that all LGMA members are required to follow. When this year’s outbreak was traced to Arizona lettuce, it marked the largest challenge since the LGMA’s were formed.

While the Food and Drug Administration (FDA) and the Centers for Disease Control and Prevention (CDC) conducted the official investigation, an LGMA task force also spent two months looking to find the cause of the 2018 E. coli outbreak.

That official investigation found the E. coli outbreak strain in canal water that irrigated the romaine fields.

According to the LGMAs its task force “invested thousands of hour conducting additional research to address all scenarios that may have led to the E. coli outbreak.”

Several changes resulted, including those buffer changes. And support for the new rules was nearly unanimous. Produce growers gave 94.7 percent approval to the changes.

LGMA imposes its mandatory food safety practices on growers that are in turn verified by state government auditors. According to the LGMAs, the two growing areas produce 130 million safety grown leafy green servings per day.

The decade-old organization says “even one foodborne illness associated without produce is unacceptable and we are committed to the further improvement of leafy greens.”

Other changes the LGMAs made just before transition involve more rigorous risk assessments for intense weather conditions; added measures for leafy greens sharing a buffer with a CAFO; more requirements on harvest equipment cleaning and sanitizing, and stronger traceback requirements.

The LGMA task force included not only its member leafy green growers and shippers, but also food safety scientists, FDA, and CDC personnel, California and Arizona departments of agriculture staff, retailers and foodservice businesses, and consumer advocates from such groups as STOP Foodborne Illnesses and Pew Charitable Trust.

The LGMA buffer in California must be at least one mile wide if the CAFO has more than 80,000 head of cattle.

As the growing gets underway in Yuma, LGMA personnel will be working to determine the impact of the changes