Estimation Function

A function that estimates loads when monitoring data are not reported for one or more monitoring periods in a reporting year. The Loading Tool applies an estimation factor to extrapolate the annual loads to account for a full 12 months of discharges. The estimation factor is calculated by dividing 12 by the sum of the number of months with DMR data and the number of months with no discharge. Section 3.2.4 of the Technical Users Background Document for the DMR Pollutant Loading Tool describes how the Loading Tool uses the function.

Search Considerations: This calculation feature uses data from the "No Data Indicator" and "Number of Report" fields in ICIS-NPDES and PCS to determine if the reported measurements account for a full 12 months of discharges. Information about this calculation option is provided in the Technical Users Background Document for the DMR Pollutant Loading Tool.