The FDA said it inspected the plant at least four times over the past five years, each time finding violations. Michael Taylor, the FDA's deputy commissioner for foods, said the agency's inspections after the outbreak found even worse problems than what had been seen there before.
Plant officials have said they were never notified of past violations.
The salmonella outbreak was traced to Trader Joe's Valencia peanut butter produced at the plant. According to the Centers for Disease Control and Prevention, 42 people were sickened, mostly children. Sunland is the nation's largest organic peanut butter plant. It produces organic, natural and traditional products for a number of national grocery and retail chains using mostly Valencia peanuts.
Valencias are a variety of peanuts that come almost exclusively from eastern New Mexico. Because of their sweet flavor, they are favored for organic and natural peanut butter products because they require few additives.
Associated Press writer Mary Clare Jalonick in Washington contributed to this report.