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Siouxland Subarea

Site Contact:
Brianne Stubblefield


Site Location:
31 counties surrounding Sioux City, IA 51101

The Siouxland Subarea is a collaborative effort of federal and state agencies, emergency managers, tribes, and local emergency responders within the geographic area surrounding the Missouri River and its tributaries from river mile marker 860 to 642. Planning and outreach activities were initiated by EPA Region 7 and partner agencies to facilitate a timely, effective, and cooperative response to a discharge of oil or release of hazardous substances that may pose a threat to public health and sensitive environments within the Sub-Area.

To guide these efforts, the Siouxland Subarea Contingency Plan was developed to coordinate the response to a substantial discharge or threat of a discharge through integrating the actions of the unique combination of private industry and local, state and federal entities that have jurisdiction within the Sub-Area. The Siouxland Subarea includes the following counties and tribal entities:

Iowa: Buena Vista, Cherokee, Clay, Dickinson, Harrison, Ida, Lyon, Monona, O’Brien, Osceola, Plymouth, Pocahontas, Sioux, and Woodbury Counties

Minnesota: Lyon, Jackson, Nobles, Pipestone, and Rock Counties

Nebraska: Burt, Cedar, Dakota, Dixon, Knox, Thurston, and Wayne Counties, as well as the Omaha Tribe of Nebraska, Ponca Tribe of Nebraska, Winnebago Tribe of Nebraska, and Santee Sioux Nation of Nebraska

South Dakota: Clay, Lincoln, Minnehaha, Union, and Yankton Counties

Our vision is to ensure the readiness of all responders in this jurisdictionally complex area to better prepare for discharges of oil, releases of hazardous substances, and to protect the public and the environment from impacts.

If you do not have a response.epa.gov account, please, click below. Otherwise, follow steps 2 and 3.

Register Your Account Here First!

NOTE: You only need to follow this registration process (Step 1) once, but you will still need to contact the OSC listed below in Steps 2-3 to be added to our contacts list.  If you have never accessed a resource on response.epa.gov, you will be redirected to your profile page on your first login attempt.  Simply go back in your browser and click the link again.

  • 1. After pressing the button above, go to your Inbox and check for an email message from mail@response.epa.gov to confirm your account by following the link provided in that message. You have 48 hours to do this!.
  • 2. Then, send an email message with your request to stubblefield.brianne@epa.gov (stubblefield.brianne@epa.gov) and provide a description of why you want access to this resource, including your first name, last name, email address, organization, and phone number.
  • 3. Once you receive communication from stubblefield.brianne@epa.gov  (stubblefield.brianne@epa.gov), return to this Web page and click one of the two buttons below to open either the map or the story.