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Tyson Foods, Inc. Clean Air Act (CAA) Settlement

(Washington, DC - April 5, 2013) The U.S. Environmental Protection Agency (EPA) and the U.S. Department of Justice announced a Clean Air Act (CAA) settlement with Tyson Foods, Inc. and several of its affiliate corporations to address threats of accidental chemical releases after anhydrous ammonia was released during incidents at facilities in Kansas, Missouri, Iowa, and Nebraska, resulting in multiple injuries, property damage, and one fatality.

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Overview of Company

Tyson Foods, Inc. (Tyson) was founded in 1935 with its headquarters in Springdale, Arkansas. Tyson is the world’s largest processor and marketer of chicken, beef and pork, the second largest food production company in the Fortune 500 and a member of the S&P 500. Tyson has revenues of more than $5.2 billion and employs approximately 117,000 people at 400 facilities nationwide.

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  • Section 112(r) of the CAA and the implementing regulations at 40 C.F.R. Part 68, require owners and operators of a stationary source that has more than a threshold quantity of a regulated substance in a process to develop and implement a risk management program. The stationary source’s risk management program is to be described in a risk management plan that must be submitted to EPA. The Tyson facilities named in this consent decree are subject to these regulations because the refrigeration systems at these facilities each contain more than the threshold of 10,000 pounds of anhydrous ammonia.
  • On October 31, 2006, an anhydrous ammonia release occurred at the South Hutchinson, KS facility resulting in one fatality and one injury. An OSHA investigation revealed that the Standard Operating Procedure (SOP) requiring personal protective equipment was inadequate and that the safety relief valve that failed was installed incorrectly, and was corroded and worn.
  • On November 8, 2006, an anhydrous ammonia release occurred at the Sedalia, MO facility resulting in three onsite injuries and $125,000 in property damage. EPA conducted an inspection on November 18, 2009, and found that the February 17-20, 2009, Process Hazard Analysis noted numerous deficiencies which had not been corrected, including Management of Change Review related to valve motors and multiple nuisance leaks occurring during the manual operation of the valves (similar to what occurred on the November 8, 2006, ammonia release).
  • On December 9, 2006, an anhydrous ammonia release occurred at the Hutchinson, KS facility resulting in ten injuries and 43.71 pounds migrating off-site. An OSHA inspection revealed that the vibration on the filter housing caused threads to deteriorate, allowing the filter oil seal to fail.
  • On December 26, 2006, an anhydrous ammonia release occurred at the Omaha, NE facility resulting in 5 on-site injuries and the evacuation of 475 employees. Both OSHA and EPA conducted inspections which revealed that Tyson’s mechanical integrity program relative to the change out of the failed valve was not implemented and there was no documentation of the inspection, testing or 5-year change-out of the safety relief valve.
  • On October 4, 2007, and November 5, 2009, there were anhydrous ammonia releases at the Perry, IA facility that injured the same employee. Tyson blamed the October 4, 2007, incident on operator error alleging that the employee failed to lock out the ammonia line when initiating a line break and failure to follow SOPs for proper personal protective equipment. However, it was also noted in incident investigation that there was a 3 way safety relief valve failure.
  • On October 30, 2007, there was an anhydrous ammonia release at the Sioux City, IA facility that resulted in one injury and the release of 3,867 lbs. of ammonia.
  • On November 5, 2009, the same employee was exposed to anhydrous ammonia, burned over 25% of his body and spent 45 days in the hospital. Again, Tyson blamed the operator and cited four operator errors in the incident investigation report: failure to pump out/lock out; failure to utilize a line breaking permit; lack of use of PPE; and failure to follow proper hand valve opening and closing SOP guidelines. However, OSHA found that there was a broken and/or defective reducer in the safety relief valve that should not have been there and that lead to the valve failure.
  • On December 13, 2010, an anhydrous ammonia release occurred at the Madison, NE facility resulting in 3 injuries and a release of 309 lbs. of ammonia. Tyson states in its May 23, 2011, response to EPA’s Information Request that given the date of the incident; the incident investigation is still open. The point of discharge was from a pressure relief valve header on the roof.

The numerous deficiencies in Tyson facilities’ RMPs described above constitute violations of 40 C.F.R. Part 68, and therefore are violations of Section 112(r) of the CAA, 42 U.S.C. § 7412(r).

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Injunctive Relief

Tyson is required to, as part of the settlement embodied in the Decree:

  • Conduct third-party audits of its current compliance with the Clean Air Act’s Risk Management Program requirements at its 23 facilities in EPA Region VII that operate on or more covered processes (ammonia refrigeration equipment). The Audit Protocol requires that third-party auditors with expertise in ammonia refrigeration systems and who are recognized experts in PSM/RMP compliance conduct paper reviews of Tyson’s engineering and design specifications as they relate to the physical systems of the covered processes at the facilities. The Auditor shall next conduct on-site Audits of the ammonia refrigeration systems at all the facilities according to a schedule set forth in the audit protocol. Within 30 days after the completion of each on-site Audit, the Auditor shall provide a report to Tyson and EPA. Within 45 days of receiving the Audit report, Tyson shall submit a response to EPA which shall include a plan to correct identified violations within 6 months for non-capital expenditures and within 12 months for capital expenditures. Once Tyson has completed implementation of any corrective measure, Tyson shall certify the completion of the work.
  • In addition, Tyson has agreed to perform non-destructive testing at certain piping used in its refrigeration systems at the 23 facilities. The non-destructive testing is designed to identify piping that was partly responsible for some of the anhydrous ammonia releases by testing threaded piping connections less than two (2) inches in diameter because of their potential for failure.

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Pollutant Impacts

The terms of the Consent Decree address accidental releases of anhydrous ammonia. The 23 facilities in Region VII have a combined inventory of 1,779,257 of anhydrous ammonia on-site. The super compliance resulting from the extensive third-party audits should eliminate the risk of future anhydrous ammonia releases.

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Health Effects and Environmental Benefits

Anhydrous ammonia is considered a poisonous gas. Exposure to its vapors can cause temporary blindness and eye damage, and irritation of the skin, mouth, throat, respiratory tract and mucous membranes. Prolonged exposure to anhydrous ammonia vapor at high concentrations can lead to serious lung damage and even death.

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Civil Penalty

Tyson will pay a $3.95 million penalty to the United States.

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Comment Period

The proposed settlement, lodged in the U.S. District Court for the Eastern District of Missouri, is subject to a 30-day public comment period and final court approval. Information on submitting comments is available at the Department of Justice website.

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For more information, contacts:

Dean B. Ziegel
Waste and Chemical Enforcement Division
U. S. Environmental Protection Agency
1200 Pennsylvania Ave, NW (MC 2249A)
Washington, DC 20460
(202) 564-4038

Anne Rauch
Office of Regional Counsel
U.S. EPA, Region VII
901 North 5th Street
Kansas City, Kansas 66101
(913) 551-7288

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