DNR, City of St. Louis warn of high methane levels near North City landfill

KSDK -- The Missouri Department of Natural Resources has teamed up with the City of St. Louis to notify residents about high methane levels at the St. Louis Demolition Landfill between Hall Street and the Mississippi River.

The DNR ordered the city to notify all nearby homeowners and businesses and to give them with methane monitors to alert homeowners if methane enters the home.

The DNR found potentially high levels of methane October 6, and immediately ordered the city to begin a notification plan for nearby residents and businesses. Further tests were performed, and DNR got confirmation of high methane levels on Oct. 14.

The landfill has three methane testing wells, and the City of St. Louis conducted sampling on Oct. 12. The southernmost well showed 4.3 percent methane by volume; the second and third wells to the north had readings of 11.3 and 46 percent methane by volume. Methane is a byproduct of the decomposition of waste and is explosive at concentrations between 5 and 15 percent. The regulatory limit for methane at a landfill property boundary is 2.5 percent by volume.

The DNR is requiring the city to develop a plan to determine the extent of the spread and a clean-up plan. The city is also required to continue monitoring the wells and report the readings to the department on a weekly basis.

The department's Solid Waste Management Program has been working with the City of St. Louis to properly close Demolition Landfill and move the facility into post-closure status. The landfill was built before the current landfill design and operating requirements took effect, so it was grandfathered in and not required to monitor for methane gas. As part of the process of properly closing the landfill, the DNR required the city to prepare an investigation plan and install three gas-monitoring wells along the western perimeter of the facility.

Residents and business owners should call 911 if they smell gas or contact the St. Louis Fire Department at 314-533-3406 if they have concerns with their monitoring device.

People who live in the area and have questions or concerns, should call the city at 314-647-3111 or call the DNR Solid Waste Management Program at 800-361-4827 or 573-751-5401.