It has come to our attention that air permits issued to grain elevators ten years ago are coming due in the next twelve to eighteen months. At the time most of these permits were initially issued, the Indiana Department of Environmental Management (IDEM), regarded the elevators as a minor source operating permit (MSOP) and processed these with less scrutiny in order to focus on larger source permits. The standard regarding MSOP permits is well-settled and has existed for several years under 326 IAC 6.5-1-2, which considers factors such as process, weight, and volume.
As the rule was established in the 1990s, it is an unlikely solution to change the standard codified in 326 IAC 6.5-1-2. As IDEM begins to renew grain elevator air permits, some members may have issues with straight truck dump pits with a capacity over approximately 12,000 bushels per hour.
IDEM may require some throughput/use limits or emissions controls on these dump pits.
Hopper trucks do not have this issue, as they generally create less dust than straight trucks. We advise members who receive straight truck deliveries to look at several alternatives in order to stay compliant.
We recommend several methods to decrease the particulate matter created by straight trucks. Members may choose to:
- Limit straight truck dumping and keep a record of straight truck dumping in order to ensure compliance with standards;
- Install baffles at the dump pit, which can achieve 21% control over air emissions; or
- Install a choke feed device at the bottom of a feeder that reduces dust emitted by straight truck dumping.
We strongly advise all ACI members to share this alert with your environmental consultants or responsible employee.
Companies should advise environmental experts on this matter and plan accordingly to ensure compliance and permit renewal.