Contact: Ralph Pribble, 651-757-2657
Saint Paul, Minn. — The U.S. Postal Service has reached an agreement with the Minnesota Pollution Control Agency, resolving air quality violations at the USPS Regional Management Support Center in Eagan, Minn. The facility did not obtain proper air quality permits from the MPCA before it installed and operated a number of boilers and diesel-fueled generators at the site.
The violations resulted in a potential increase in emissions of several regulated air pollutants, including particulate matter, sulfur dioxide and nitrogen oxides. These pollutants can cause respiratory irritation in humans and would add to the overall air pollution in the area.
The violations were discovered in 2009, when the USPS applied to the MPCA for an air quality permit covering on-site generators and gas-fired boilers used to heat the facility, located at 2825 Lone Oak Parkway in Eagan. The application stated that this would be the facility’s first air quality permit. The MPCA requested more information and found that 14 gas-fired boilers and seven diesel-fueled generators had been installed at the facility between 1998 and 2004.
Instead of using the generators only for traditional backup electrical generation, the facility entered into a service agreement with Northern States Power Co. (now Xcel Energy) to use them for "peak shaving," in which on-site generators are used to offset electrical demands at times of peak usage.
However, that meant the generators could potentially operate more frequently and therefore have potential emissions of several regulated air pollutants above 250 tons per year, which requires a higher category of state and federal air quality permits. Because the facility did not seek the proper permits, the MPCA had no opportunity to set appropriate permit conditions to control these increased potential emissions.
The facility used the five original generators for peak shaving from 1998 through 2003, and all seven generators were used for peak shaving from 2004 through 2009. The facility did not renew its agreement with Excel Energy and is no longer using its generators for peak shaving, but rather as standby generators for traditional emergency use.
The investigation also found that Emission Inventory Reports had not been submitted from 1998 through 2007. The USPS will pay $13,000 to the MPCA and agreed to a compliance schedule for completing corrective actions, including submitting required Emission Inventory Reports and applying for the proper air quality permits. The USPS has completed all the required corrective actions.
When calculating penalties, the MPCA takes into account how seriously the violations affected the environment, whether they were first-time or repeat violations, and how promptly they were reported to appropriate authorities. Penalties also attempt to recover the calculated economic benefit gained by failure to comply with environmental laws in a timely manner. For a comprehensive list of enforcement actions by the MPCA, visit the Quarterly Summary of Enforcement Actions page.
