Midwest 2016 Gas Leak Public Information Sheet

Media Contact for CNCHD:

Kelly Weidenbach, Executive Director Casper-Natrona County Health Department Phone: 307-262-9320

Media Contact for FDL:
Justin Westmoreland, Health and Safety Director Fleur de Lis Energy, LLC
Phone: 719-251-4198

Media Contact for Natrona County School District: Kelly Eastes, Director of Community Partnerships Natrona County Schools
Phone: 307-253-5382 

Public Health Updates:

  • The Agency for Toxic Substances and Disease Registry (ATSDR) has completed its formal review of air sampling data from Midwest School from May and June ATSDR concluded that the air quality events that occurred in Midwest School in May 2016 constituted an urgent health hazard and that school officials and others who determined that the school needed to be evacuated were right in doing so.
  • Areas of the school that were sampled in May showed carbon dioxide (CO2) levels that exceeded health guidelines of 5,000 ppm and areas of the school were shown to be oxygen-deficient, which was an immediate health Areas of the school that showed excessive levels of carbon dioxide (CO2) included the library, library office area, bathroom in library, library hallway, Classroom 105 A/B, Classroom 106, Classroom 107, Classroom 108, southwest girls’ bathroom, southwest boys’ restroom, main office, Classroom 101, Classroom 15, Classroom 16.
  • Air sampling data from May and June 2016 showed the presence of multiple volatile organic compounds (VOCs), including The concentrations of benzene detected in the school on May 26 posed an acute health hazard, warranting immediate evacuation of the building. The highest level of benzene detected on May 26 was in Classroom 106 with 1.85ppm (measured by hand-held monitors), which was a 200-fold exceedance of the ATSDR acute air comparison value.
  • Benzene is a chemical compound that can cause both short term and long term health affects in humans exposed. People who breathe in high levels of benzene may develop the following signs and symptoms within minutes to hours of exposure: drowsiness, dizziness, rapid or irregular heartbeat, headaches, tremors, confusion, unconsciousness, and death (at very high levels). Direct exposure to benzene of the eyes, skin, or lungs can cause tissue injury and Long term health effects of exposure to benzene can be serious, as benzene is a cancer-causing compound. Long term exposure to benzene has a major effect on blood. Long term exposure is typically defined as more than one year. Benzene causes harmful effects on the bone marrow and can cause a decrease in red blood cells, leading to anemia. It can also cause excessive bleeding and can affect the immune system, increasing the chance of infection. Benzene can cause cancer in humans. Long term exposure to benzene in the air can cause leukemia, a cancer of the blood-forming organs. Some women who breathed high levels of benzene for many months had irregular menstrual periods and a decrease in the size of their ovaries. It is not known whether benzene exposure affects the developing fetus when pregnant women or fertility in men. Some animal studies have shown low birth weights, delayed bone formation, and bone marrow damage when pregnant animals breathed benzene. Any exposure to benzene should be avoided when possible.
  • Because benzene is known to be cancer-causing, public health officials explicitly asked that ATSDR determine cancer risk for adults and children exposed to benzene at detected levels in the school indoor air over many The cancer risk for benzene was specifically evaluated because the indoor benzene concentrations from May 26 exceeded recommended limits. ATSDR calculated lifetime excess cancer estimates (i.e., cancers over population background rate) from exposure to benzene at the detected concentrations for both staff and students. Risk estimates were adjusted to account for the relevant frequency and duration of exposure (i.e., different scenarios representing a student in the building 8 hours per day x 5 days per week x 9 months per year over 12 years vs. a school staff member in the building 8 hours per day x 5 days per week x 350 days per year x 30 years). Cancer risk estimates are statistical probabilities and intentionally conservative (i.e., health-protective). Estimates of excess cancer risk were on the order of one additional cancer per 100,000 people to three additional cancers per 1,000,000 people for adult workers. Excess lifetime cancer risk for children was calculated to be even lower. The calculated risk estimates for Midwest School are within or below the EPA target risk range. In summary, the increased risk of cancer to staff and students of Midwest School is measurable but extremely low.
  • Unfortunately, we do not know what the indoor air quality within the school looked like prior to the initial testing conducted on May We know that dangerous levels of carbon dioxide (CO2) and volatile organic compounds (VOCs) were detected in the school on May 25 via hand-held air sampling monitors, which prompted the evacuation of the school. The air quality on June 16 and June 17 was remarkably better than the conditions documented on May 25.
  • No single substance found in the air at the school on June 16 and June 17 exceeded ATSDR and/or EPA indoor air quality recommended The recommended thresholds represent concentrations of substances in the air in which humans (adults and children) might be exposed daily over long periods of time and not experience adverse health effects. In sum, no single substance was found in the air at the school on June 16 and June 17 at a level that indicated a risk for acute human health effects.
  • Hydrogen sulfide (H2S) has not been identified in air samples in the school to-date.
  • The air quality testing completed on May 26, May 30, June 16 and June 17 in the school represent single data points, a snapshots in time, of the indoor air quality in Midwest The air quality in the school likely fluctuates daily depending on a variety of natural and man-made factors. Public health agencies and our partners are currently working on plans to ensure that air quality in the school is safe at all times and identified risks to indoor air quality are mitigated.
  • The Casper-Natrona County Health Department provided a list of recommendations to the Natrona County School District for re-opening and re-occupying the The recommendations include development of an indoor air quality mitigation plan to address the known air quality issues, implementation of the mitigation/protective measures at the school, another round of air quality sampling post-mitigation to confirm that mitigation efforts were successful and that the school is ready to be re-occupied, the development of an indoor air quality monitoring plan, placement of carbon dioxide (CO2) monitors in the school as part of the air quality monitoring plan, and development of a response plan for if/when future indoor air quality problems are identified in the school.
  • The Casper-Natrona County Health Department and the Wyoming Department of Health have completed 139 human health surveys among staff and students at the Epidemiologists from the Wyoming

Department of Health are analyzing the results of these surveys to describe the frequency of self- reported adverse health effects experienced by individuals who were in the school daily, healthcare utilization, and health concern data. The data analysis process will likely take several weeks to complete. A final epidemiologic report will be published by the Wyoming Department of Health and will be made publically available once complete.

  • Public health officials support the re-opening of the school if the post-mitigation, air quality sampling demonstrates that all substances in the air within the school are at concentrations that are protective to human health and once the school district is able to implement the recommended indoor air quality monitoring and response

Natrona County School District #1

  • School activities for Midwest School students and staff have begun at Westwood Elementary school for Pre-K through 8th grades and at Roosevelt/PIC Building for 9th through 12th grades until Midwest School is safe to occupy per public health officials’
  • No person is allowed to enter the Midwest School property without prior coordination and approval from the Natrona County School District Executive Director of Business
  • The school district is currently in the process of hiring an independent consultant for environmental and industrial hygiene to advise the school district on current and future mitigation strategies, reviewing and finalizing the plan to reoccupy the school, and to ensure public health and safety of staff, students, and visitors to Midwest Several interviews for this consultant have taken place to-date. The school district hopes to have the consultant hired by October 1, 2016.
  • Safety of students and staff is the highest While folks are anxious to re-occupy Midwest School, the school district will not compromise the process outlined by CNCHD and their consulting experts for a speedy resolution that jeopardizes our students’ and our staff’s safety, health, and wellbeing.


FDL Operating, LLC Updates:

  • A comprehensive gas sampling plan for Midwest School was completed June 16 and June 17 with guidance from local public health officials and Results from this sampling event were turned over to CNCHD and to ATSDR for public health review and interpretation.
  • No abnormal carbon dioxide (CO2) levels have been detected in Midwest School since June 16 and June 17
  • FDL is maintaining an information contact number at (307) 462-9112 for any questions or concerns from the residents of
  • The company conducted a comprehensive search for additional point sources of No additional incidents were reported or discovered beyond this isolated incident.
  • Company teams have completed a comprehensive evaluation of every well bore drilled within ½ mile of the
  • FDL teams successfully sealed a well adjacent to the
  • FDL has retained an environmental consulting company to advise FDL on soil remediation options at the Midwest
  • Monitoring of wells and analysis of current and future operations surrounding the school is
  • FDL Operating is working with the Midwest Town Council to provide additional gas monitoring throughout the FDL staff are available to check Midwest and Edgerton homes and businesses for abnormal gasses 24-hours a day. Requests may be made by calling 307-462-9112 or 307-437-9500



Recent News