This Notice of Warning constitutes formal notification by the United States Environmental Protection Agency, Region 9 (EPA) pursuant to Section 14(a)(4) of FIFRA. Based on inspections conducted at farms operated by the Tohono O'odham Farming Authority (TOFA) and owned by the Tohono O'odham Nation ( the Nation ), EPA has determined TOFA and the Nation violated Section 12(a)(2)(G) of FIFRA, 7 U.S.C. Section 136j(a)(2)(G). The EPA inspections were conducted at the San Lucy, Schuk Toak, and Vaiva Vo Farms on April 3 and 4, 2017.