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Hyperion Refinery



Hyperion Misses Required Deadline to Break Ground on Oil Refinery

Hyperion Energy Center proposed an enormous oil refinery in elk  Point, South Dakota, west of Sioux City, Iowa.  A requirement of the air permit was that construction was to begin on or before March 15, 2013.  Hyperion missed that deadline.  Hyperion planned to refine sour crude that was extracted from the tar sands in Canada.  The refining process creates significant air pollution.  The prevailing winds would blow those pollutants into Iowa, targeting Sioux City and the neighboring Loess Hills.  The Iowa Chapter was also concerned about discharges of water into the Missouri River, including the effect on water temperature, pollutants entering the water and the effect on fish.  The Missouri River and Big Sioux River are an important migration flyway for birds.  Hyperion allowed the options to purchase the land to expire in the fall of 2012.


Habitat in the Loess Hills will be negatively impacted by the pollution emitted by the Hyperion Refinery.


Loess Hills cat steps


Toxic Tar Sands: Profiles from the Front Lines

Read stories of individuals from the US and Canada impacted by tar sands.


Tar Sands Invasion: How Dirty and Expensive Oil from Canada Threatens America’s New Energy Economy

Learn more about the oil industry's plants for a massive project to export millions of barrels more per day of dirty tar sands oil from Alberta, Canada to the United States


Dirty Oil Sands: Uncovering the Canadian oil sands disaster

Read reports, look at photographs, find fact sheets, maps and take action.




You can make a tax deductible donation to the Iowa Chapter.


Chapter Meets with EPA 

Iowa Chapter representatives met with EPA Region VII air quality and water quality staff on June 22, 2011.  Chapter representatives dialogued with EPA staff about the Chapter's concerns regarding the proposed Hyperion refinery.  Read the Chapter's presentation.

The directors of the Iowa DNR and the Iowa Department of Economic Development contacted the administrator of EPA Region VII wanting the Chapter's presentation changed to clarify that the EPA had nothing to do with preparing the presentation Chapter representatives made in June 2011 about the Hyperion refinery project.  See the Chapter's response. 


Iowa Chapter Information Documents:

(all are pdfs and available to download)

HAP Monitor Needed in Sioux City

Missouri River Flyway

Exposing the Truth about Refinery Jobs

Transportation Pollution

Hyperion Refinery informational brochure

How to Contact Decision Makers

Mercury in Iowa’s Lakes and Streams


South Dakota Department of Environment and Natural Resources has been monitoring the Hyperion site to get background information and installing test locations for permanent monitoring.  See the monitors map.

The air monitors are not set to evaluate the air emissions in the strongest prevailing wind direction.  The prevailing winds are strongest from the northwest.  That puts Sioux City as the target for the emissions. Iowa State University’s Department of Agronomy Iowa Environmental Mesonet has studied wind direction around Sioux City for more than 60 years.  The Windrose Plot indicates the average prevailing winds in and around Sioux City.  Average monthly Windrose Plots from January 31, 1948, through September 9, 2010, are also available.

Summary of Concerns about the Hyperion Refinery as presented to EPA Region VII Staff June 22, 2011


A special thank you to the volunteers who have worked on the Hyperion refinery issue and assisted in preparing materials including Jim Redmond, Jane Clark, Ginger Soelberg, Pam Mackey-Taylor and Charlie Winterwood. I appreciate their work on this project.

~Neila Seaman, Director

See more information about this issue at Sierra Club's South Dakota website.

Related Links:

DNR Director Writes to South Dakota Department of Environment & Natural Resources Director

In July 2010, Iowa DNR Director Richard Leopold sent a letter to his counterpart in South Dakota asking the neighboring state to take consideration of a list of recommendations.  Read Rich's letter.

In August 2010, South Dakota wrote back to the Iowa DNR.  Read South Dakota's response.

From the Sioux City Journal:

"Hyperion: Why take the risk?" -- February 14, 2010

"Decision on air-quality permit expected Thursday: Hyperion in the balance" -- August  16, 2009

"Hyperion's impact? It's personal" -- April 6, 2008

From Circle of Blue:


Tar Sands Oil Production, An Industrial Bonanza, Poses Major Water Use Challenges -- August 2010

To learn more, go to 


Last Updated 06/12/2013

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