By Paul J Sniadecki, MLSA Board Director
What does green energy have to do with our lakes and streams? To answer the question, we need to understand one aspect of being carbon neutral. As many readers know, using fossil fuels adds carbon to the atmosphere. When we use gas to heat our buildings, fuel our vehicles, and cook with, we are releasing additional quantities of carbon as a byproduct. What if there was a way to be almost fully carbon neutral? There is and it is called “biogas.” Anaerobic digesters create biogas when they break down organic materials like food waste, waste water. manure and sewage sludge. The biogas can be captured and used for energy production. So, the carbon captured naturally, earlier, by the growing organic matter is not an additional load to the atmosphere.
The digesters do create an amount of “digestate” which can be applied to farmland as fertilizer and other uses. That is where our lakes and streams could be impacted.
A large digester in west Michigan was previously regulated by EGLE’s Solid Waste Division but was notified the Water Resources Division would be taking over regulation of the digestate. So, the facility must now operate under a groundwater discharge permit, rather than the agricultural use authorization that previously allowed the company to apply their digestate as fertilizer through the state’s solid waste program.
EGLE spokesperson Jill Greenberg said without careful management of this material(digestate), significant impacts could happen to groundwater used as a drinking water source. Overapplication can cause surface water quality problems, such as the development of toxic, harmful agal blooms and excess aquatic plant growth that choke waterways. In addition, any foreign materials contained in the waste materials accepted can introduce contaminants onto farm fields that could threaten food production. The permit that will be issued by EGLE will reasonably mitigate these concerns.
In December 2023, a bi-partisan group of Michigan legislators sent a letter of concern to EGLE about this permitting change. They strongly urged EGLE to reconsider the permitting requirements for community digesters. They hoped that by engaging stakeholders and Michigan citizens in the process, a more viable solution can be developed.
MLSA will continue to monitor this situation as our lakes and streams need to be protected.