Rock Springs, WY — Simplot

UPDATED: 01/11/2018 — see Change Log

OWNER: Simplot Phosphates LLC (J.R. Simplot Company)
PROJECT: Brownfield ammonia plant[memberful does_not_have_subscription=”1314-ammonia-industry-annual-subscription,1311-ammonia-industry-monthly-subscription,3338-ammonia-industry-30-day-subscription”]

COST (reported): $350 million
JOB CREATION (reported): 40 permanent, 750 construction (peak), +237 permanent at existing site — see Job Openings [LINK]
START-UP DATE (reported): 2017

Ammonia 600 stpd [Membership required] [Membership required]
Units: stpd, stpy, mtpd, mtpy = short/metric tons per day/year.
[1] United States Geological Survey (USGS) Mineral Yearbook, Nitrogen gives capacity in metric tons per year, calculated as “engineering design capacity adjusted for 340 days per year of effective production capability,” rounded to three significant digits. Source: most recent year, Table 4: Domestic Producers of Ammonia,
[2] Company press release. Sources: linked below.
[3] [Membership required]. Sources: linked below.
[4] [Membership required]. See Methodology.


[memberful does_not_have_subscription=”1314-ammonia-industry-annual-subscription,1311-ammonia-industry-monthly-subscription,3338-ammonia-industry-30-day-subscription”]


Find more information by browsing the sources below, or see it here and now by becoming a member.

Members have instant access to additional information, including project status, likelihood of completion, feedstock and end products, and research notes.

See an example page, or get more information about membership.

Annual Membership ($199) →

Thank you for supporting the ongoing maintenance of this site.


[memberful has_subscription=”1314-ammonia-industry-annual-subscription,1311-ammonia-industry-monthly-subscription,3338-ammonia-industry-30-day-subscription”]

Simplot began building its new ammonia plant, adjacent to its existing phosphate fertilizer plant, in October 2014. The project was initially scheduled to be complete in Q3 2016, but delays pushed this back. The new plant was mechanically complete in March 2017 and became fully operational in September 2017. Simplot’s investment is “one of the largest in company history,” and makes it self-sufficient for ammonia.

COST: $350+ million
JOB CREATION: 40 permanent, 750 construction, +237 at existing site — see Job Openings [LINK]
START-UP DATE: September 2017, originally Q3 2016
LIKELIHOOD: Likely — see Methodology

Ammonia 600 stpd 600 stpd 198,673 mtpy
MAP 1,800 stpd 596,020 mtpy
Units: stpd, stpy, mtpd, mtpy = short/metric tons per day/year.
[1] United States Geological Survey (USGS) Mineral Yearbook, Nitrogen gives capacity in metric tons per year, calculated as “engineering design capacity adjusted for 340 days per year of effective production capability,” rounded to three significant digits. Source: most recent year, Table 4: Domestic Producers of Ammonia,
[2] Company press release. Sources: linked below.
[3] Wyoming DEQ permit documents, adjusted from hourly rate (x24). Sources: linked below.
[4] Adjusted Capacity is in metric tons per year assuming operations for 365 days per year; based on permit documents. See Methodology.

FEEDSTOCK: Natural gas

In October 2014, Simplot announced that it was breaking ground for a new ammonia plant, adjacent to its phosphate fertilizer complex in Rock Springs, Wyoming, with an original start-up date of Q3 2016.

In March 2017, the ammonia plant was mechanically complete and undergoing testing; although the company made no announcements during this period, the commissioning phase was completed in September 2017, and the new ammonia plant is fully operational.

At the end of July 2017, Simplot’s CEO was quoted in the local media saying that “We will be among one of the cheapest producers [of phosphate fertilizer] in the United States once we have the new ammonia plant up and going in Rock Springs, Wyoming.”

Simplot’s $350 million investment was “one of the largest in company history” – the initial estimate had been $170 million. As a private company, Simplot has no need to disclose financial details, and it has not provided any recent update on the capex amount. The Rock Springs Chamber of Commerce’s April 2016 Newsletter implied that the budget may have doubled or tripled during construction, to “$700 million – $1 billion,” however, in May 2017, company reps told me that capex remains within 10% of the expected $350 million.

When the plant is operational, it will make Simplot “self-sufficient on ammonia,” not just at Rock Springs but across the company’s MAP production operations across the US. This “will significantly enhance our long term sustainability in the phosphate marketplace … ensuring long-term, low cost raw materials to our facilities.”

The Rock Springs site previously purchased ammonia at a rate of about 90,000 stpy. The ammonia reacts with phosphoric acid (52% P2O5) to produce MAP fertilizer. An expansion project, to increase P2O5 production from “a baseline level of 400,000 tons/year to a design capacity of 440,000 tons/year,” began in 2012 and was completed ahead of schedule, in June 2014.

The new ammonia plant at Rock Springs is producing about twice as much ammonia as can be consumed on-site: the rest is shipped to Simplot’s other phosphate plant, the Don plant, in Pocatello, ID, which has similar fertilizer capacities, consuming around 90,000 tons of ammonia per year.

Simplot “received proposals from bidders” in April 2013, filed the air permit application in June 2013, started to provide public information in support of the project in January 2014, and filed the industrial siting permit application in March 2014, which was approved in July 2014.

CH2M Hill provided consultancy services and Linde Engineering was the “technology provider and primary engineering, procurement, and construction contractor.” This is the first North American plant to use Linde’s proprietary ammonia process, which combines Linde’s hydrocarbon processing technology with Casale’s ammonia synthesis loop.

In July 2016, local news reported that Simplot and Linde Engineering workers had achieved a million man-hours without a lost-time injury.

The ammonia plant and storage tanks, which hold 18,000 tons of ammonia, were built on a 20-acre plot within Simplot’s existing site. Questar Pipeline Company installed “2.5 miles of new 8 inch diameter pipe” to increase site’s supply of natural gas, because the existing pipeline did not provide the “necessary quality or pressure.” The ammonia plant is expected to consume 18 million standard cubic feet per day of natural gas (feedstock and fuel), and 15 MW electricity, provided by Rocky Mountain Power.

No additional water permit was necessary because the “small incremental water increase” (about 150 gallons per minute) required to operate the ammonia plant was within the levels already permitted for the site. This water is sourced from the city of Rock Springs.

The Rock Springs fertilizer complex was originally owned by Chevron and began operations in 1986. Simplot purchased the plant in 1992 in a joint venture (SF Phosphates Ltd) with Farmland Industries, before taking sole ownership in 2003. The site consists of two sulphuric acid plants, two phosphoric acid plants, a superphosphoric acid plant, and an ammonium phosphate plant. A slurry of phosphate rock is delivered through a 96 mile pipeline from Simplot’s mine in Vernal, Utah.

Although Simplot had not recently produced ammonia at any of its facilities, the company has plenty of experience as an ammonia producer: its last phase ended in 2006, when Simplot Canada Ltd sold its nitrogen business, including the ammonia plant at Brandon, Manitoba, to Koch Nitrogen.[/memberful]

View larger map with all ammonia plants.

ADDRESS: 515 South Highway 430, Rock Springs, WY 82902, United States



  • USGS: Minerals Yearbook, Nitrogen [RECENT / ARCHIVE]
  • EPA Emissions data: Greenhouse Gas Emissions from Large Facilities: Simplot Phosphates [LINK]
  • Risk Management Plan: Right to Know Network: Simplot Phosphates LLC [LINK]
  • Operating Permit (Title V): Wyoming DEQ: Simplot [LINK] / Title V Permit, 2014 [PDF]
  • Construction Permitting: Wyoming DEQ: Rock Springs Ammonia Facility [LINK]


  • 07/26/2017: Idaho State Journal: Simplot CEO visits Pocatello [LINK]
  • 03/28/2017: Wyoming Business Report: Southwest digs out of cold, wet winter [LINK]
  • 07/07/2016: Sweetwater Now: J.R. Simplot Company and Linde Engineering North America Achieves 1 Million Man-Hours Without a Lost Time Injury [LINK]
  • 04/21/2016: Wyoming Business Report: Simplot expansion will open up 40 new jobs [LINK]
  • 12/04/2015: Wyoming Business Report: J.R. Simplot to pay nearly $43M to clean SO2 pollution [LINK]
  • 12/03/2015: Sweetwater Now: J.R. Simplot Company to Reduce Emissions at Sulfuric Acid Plants in Three States [LINK]
  • 10/07/2014: Linde press release: Linde Engineering North America building ammonia plant for J.R. Simplot [LINK]
  • 10/06/2014: Simplot press release: J. R. Simplot Company to Build New Ammonia Plant in Rock Springs, Wyoming [LINK / PDF]
  • 06/10/2014: Wyofile: State board splits in approving $350 million Simplot ammonia plant [LINK]
  • 06/03/2014: Wyofile: State ready to green-light Simplot Rock Springs ammonia plant [LINK]
  • 01/08/2014: Sweetwater Now: Possible expansion of Simplot facility discussed [LINK]
  • 07/26/2012: Simplot press release: Rock Springs Expansion [PDF]
  • UNDATED: Simplot facility fact sheet: Simplot Phosphates LLC, Rock Springs [PDF]

Leave a Reply

Your email address will not be published. Required fields are marked *