NTMWD Landfill employs high and low-tech solutions to tackle odor management
Solid waste disposal is one of three essential services provided by the North Texas Municipal Water District (NTMWD). The 121 Regional Disposal Facility (121 RDF) is a state-of-the-art municipal solid waste landfill that includes a composting facility and a Landfill Gas-to-Energy Beneficial Reuse Plant on-site. When the 121 RDF began operations in 2004, the area surrounding the landfill was mostly rural, but subdivisions have since taken the place of the agricultural fields.
Being a good neighbor to the communities surrounding the landfill is of utmost importance to Mike Friesen, Director of Solid Waste for NTMWD.
“Our goal is to be virtually undetectable, and the residents should not experience any odor issues from the landfill,” he said.
Because a landfill is made of decomposing organic material, Friesen’s goal can be a tough one to achieve, as demonstrated by recent challenges leading to increased odor concerns. He stressed that every complaint is taken seriously.
“We emphasize for people to contact us whenever they smell something. The sooner we know about it, the sooner we can start working to investigate and address the issue,” he said. “We have received calls late at night and early in the morning, and we'll send somebody out to investigate the situation.”
Determining the source of odors can be complex as there are other odor sources in close proximity to the 121 RDF including a cattle feedlot, residential septic systems, a small wastewater treatment plant serving a residential subdivision, and a compost facility.
Friesen and the team at the 121 RDF use a combination of methods to monitor the odor and find problem areas. Some are high-tech, like flying emission-detecting drones over the surface or using methane monitoring probes. Others are low-tech, like using their own sense of smell.
“We perform a morning and an evening odor patrol,” he said. “We monitor the perimeter of the landfill, and then we also travel through the surrounding neighborhoods. We document any odors, where they were detected, the source of the odor and the intensity of the odor. If it's coming from our facility, we will track it down to a centralized location and make operational adjustments accordingly such as additional cover, increased local vacuum to the landfill gas collection system, or maintenance to the landfill gas collection system infrastructure.”
Additionally, the landfill covers the waste daily to contain odors, prevent storm water runoff contamination and prevent animal activity.
The landfill meets or exceeds the Texas Commission on Environmental Quality regulations for emissions and is inspected regularly by the agency. However, there are instances when odors do occur. This is usually due to maintenance or construction to the landfill gas (LFG) collection system but can also occur due to changes in weather conditions such as low-pressure systems that often bring rain events. Also, as the trash in the landfill decomposes, the landfill can settle unevenly. This can cause the LFG collection infrastructure to be damaged or cracks to form in the soil cover which could allow for emissions. Because the landfill doesn’t accept hazardous materials, there are no harmful compounds emitted. The odors may be unpleasant, but they are not a health hazard. And, when collected in the LFG collection system and processed at the gas-to-energy plant, they are useful.
“Landfill gas is a renewable energy source, and we provide enough energy to heat over 20,000 homes a year from the energy coming from our landfill,” said Friesen.
The third-party contractor who runs the gas-to-energy plant on the facility continually expands the LFG collection system to increase gas collection as more waste is brought to the landfill.
Odor management is a tough task, but the solid waste professionals at the 121 RDF see it as more than just part of their jobs. It’s a way to care for the communities in which they live and work.
“We work here, and we have employees who live in Melissa, Anna and the surrounding areas,” Friesen said. “These are our friends, family and neighbors who we want to treat as well as we want to be treated ourselves…we strive to go above and beyond what is required by the regulations to run the 121 RDF, providing an essential service for the region’s solid waste disposal.”