The science surrounding emission rates from livestock facilities is still not well understood. Some Land Grant Universities have developed emissions estimators based upon currently available information, and EPA references cite such sources as providing useful information for estimating emissions. However, EPA does not endorse any specific methodology. For estimates that are tailored to a specific region or species, contact your Land Grant University or commodity association for possible resources. The University of Nebraska developed an Ammonia Emissions Estimator that estimates ammonia emissions for several general applications.
EPCRA requires that upper and lower limits on the estimate be provided. The requirement to report is based upon the upper limit. For CAFOs that must report, most are expected to need to do so based upon ammonia emissions. Comparatively less information is available on hydrogen sulfide. If an estimate for hydrogen sulfide cannot be determined or the estimated maximal daily release is less than 100 pounds, then do not report hydrogen sulfide emissions.
Note: You do not need to submit emissions calculations with the EPCRA report; however, keep them on file for documentation of when and how the estimates were made.
For more information on this rule see:
EPCRA Requirements
This FAQ was developed and reviewed by Chris Henry and Rick Stowell, University of Nebraska and Carol Galloway, US EPA Region 7
