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Simplot Settlement Information Sheet

(Washington, DC - July 9, 2020) - On July 9, 2020, the U.S. Environmental Protection Agency (EPA) and the U.S. Department of Justice announced a settlement with J.R. Simplot Company and its subsidiary, Simplot Phosphates LLC (Simplot), involving Simplot’s Rock Springs, Wyoming, manufacturing facility.

Overview of Companies

J.R. Simplot Company is a privately-held food and agribusiness company, incorporated in Nevada, with its principal corporate offices in Boise, Idaho. At the Rock Springs facility, Simplot principally manufactures phosphoric acid and phosphate fertilizer products.  Simplot was an owner and operator of the facility beginning in 1992, in a joint venture with Farmland Industries, Inc.  Simplot has been the sole owner and operator since 2003, when it purchased its joint venture partner’s interest in the operation and renamed it Simplot Phosphates, LLC.

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This settlement resolves Simplot’s liability for  alleged violations under the Resource Conservation and Recovery Act (RCRA), including failure to determine if a solid waste is a hazardous waste (40 C.F.R. § 262.11); treatment, storage or disposal of hazardous waste in the phosphogypsum (gypsum) stack without a permit or interim status (42 U.S.C. § 6925(a) and 40 C.F.R. Parts 264/265 and 270); failure to perform land disposal determinations and to meet land disposal restrictions for hazardous wastes (40 C.F.R. Part 268); and failure to submit complete Emergency Planning and Community Right-to-Know Act (EPCRA) annual toxic release reports (42 U.S.C. § 11023 and the implementing regulations at 40 C.F.R. Part 372). 

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Injunctive Relief

The injunctive relief required by the consent decree includes:

a)  Making a RCRA hazardous waste determination for all non-Bevill excluded wastes not managed in accordance with the requirements of the settlement and, if hazardous, manage such wastes in compliance with RCRA Subtitle C;

b) Constructing and operating an Acid Value Recovery System (AVRS) to recover, as a product, phosphate-bearing materials that were previously disposed of in the facility’s gypsum stack, a large outdoor impoundment;

c) Preventing leaks and spills by installing new tanks and improving containment of existing tanks, pipes, and sumps;

d) Implementing a Best Management Practices (BMP) plan to continuously improve identification and control of solid wastes from phosphoric acid and sulfuric acid production; and institute BMP training;

e) A comprehensive gypsum stack closure plan and securing and maintaining financial assurance to cover the cost of closure and long-term care, which will consist of $126 million in surety bonds, due within 30 days of the effective date of the settlement, and an $8 million annual aggregate liability coverage for sudden and non-sudden accidental occurrences; and

f) Revising and resubmitting EPCRA toxic chemical release inventory reports for the years 2004 through 2013 to include additional compounds whose quantities were not previously estimated.

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Pollutant Impacts

Process wastewater and gypsum solids are piped from the manufacturing plant to the gypsum stack, and all of the ditches and ponds connected to the gypsum stack are lined with high density polyethylene (HDPE).  A HDPE liner is also present under the gypsum stack which prevents the release of potentially hazardous wastewaters (corrosive) to the environment.  A lined intercept ditch is located downgradient from the gypsum stack to detect and capture any leaks, and Simplot conducted a four year investigation that found no environmental impacts to the groundwater, and installed several dozen additional groundwater monitoring wells to enhance its ability to quickly detect and respond to any leaks around the gypsum stack. 

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Environmental Benefits 

By operating its Acid Value Recovery System, Simplot will reduce the quantity of acidic wastes sent to the gypsum stack for disposal, and beneficially re-use in production the phosphate from those materials that otherwise would need to be obtained from mined phosphate ore.  Simplot will also implement a Best Management Practices plan to better identify and prevent leaks and spills from its manufacturing plant.  All of these projects are designed to ensure that acidic wastewaters and any contamination are controlled within the lined gypsum stack system and plant site.  Simplot developed a gypsum stack closure plan to ensure that when production operations cease, all acidic wastewaters will be neutralized and treated to remove any hazardous contaminants, and that the gypsum stack will be structurally stable and revegetated.

Simplot is providing surety bonds to secure financial assurance for closure of its gypsum stack in the amount of $126 million so that the taxpayers will not be at risk of paying for future closure or cleanup at the facility. 

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Civil Penalty

Simplot will pay a civil penalty of $775,000 to resolve the alleged past violations of RCRA and EPCRA.

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Comment Period

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

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Contacts for Further Information

Max Greenblum
U. S. Environmental Protection Agency
1595 Wynkoop Street (8ORC-R)
Denver, Colorado  80202

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