A facility subject to EPCRA §313 exceeds the processing threshold for mercury, and determines that the total amount of mercury released from the facility in a particular year is 0.07 pounds. What level of precision must the facility use to report when filing a Form R for a persistent bioaccumulative toxic (PBT) chemical, such as mercury?
As EPA stated in the PBT final rule, “Facilities should continue to report releases and other waste management amounts greater than 1/10 of a pound (except for dioxin and dioxin-like compounds), at a level of precision supported by the accuracy of the underlying data and the estimation techniques on which the estimate is based” (64 FR 58734, October 29, 1999). EPA recommends that values such as 0.07 pounds either be rounded up to 0.1 pound or reported as they are if the underlying data and estimation techniques support that level of precision. However, it is up to the facility to determine, based on the accuracy of the underlying data and the estimation techniques on which the estimate is based, whether it would be appropriate to round the value to 0.1 pound, report the value as is, or round the value to zero.