Winter 2022 Landfill Odor Control Update

We’ve been working hard and making major investments to reduce odor around the South Wake Landfill. We’ve made some encouraging progress over the past year, and there are many more improvements to come.

Based on the data we’ve collected from residents’ odor reports, we turned a corner in August 2020. That’s when we committed to covering the working face of the landfill each night with a full layer of dirt and industrial tarps. In the past, we sometimes used a spray-on product called Posi-Shell, which saved time and money, but just didn’t meet our standards for trapping odors. As the chart below shows, the switch to using dirt every day has made a measurable difference.

A bar chart showing the average number of odor reports per month at the South Wake Landfill from May 2019 to December 2021.

We’ve also seen dividends from our ongoing investment in the landfill gas extraction system. As the landfill grows, we continue to add new wells, update our equipment/technology and install redundancy and back-up features to minimize system downtimes. Just this week, work is underway to drill 11 more wells, which will bring our total to over 100. And we’re putting that landfill gas to work too. Today, it generates enough electricity to power up to 17,000 homes. In 2023, we’ll have a renewable supply of natural gas.

On the horizon, we’re moving to invest $3.7 million to implement “interim cover” in the next fiscal year, which starts July 1. This project could reduce odor reports by up to 30%, according to estimates. Interim cover bridges the gap between daily cover – the dirt and tarps we use to seal up the working face at the end of each day – and the permanent final cover we apply when a section of the landfill is full. Over the next 11 years, we’re projected to invest more than $13 million in this solution.

As always, we appreciate your understanding and patience as we work to reduce odors at the South Wake Landfill.