ECMPS Support

Recently, there have been a number of questions about year-to-date (YTD) summary values. These are the data which are reported in Year to Date Total in the Summary Value Data section of the emissions data XML.

The question which is being asked is what to do in the event that the reported Year To Date Total does not match the EPA value calculated during the emissions evaluation. If it is discovered that the problem is that earlier report summary value data were incorrect, there may be a fairly simple solution.

First, some background information is in order. For each quarter, sources are to submit Current Reporting Period Total and Year to Date Total data for every relevant parameter. These are both in the Summary Value Data part of the emissions data XML. During the emissions evaluation, the Client Tool calculates the EPA calculated value for both of these data based on the reported hourly data. If the reported Current Reporting Period Total and Year to Date Total are within the acceptable tolerance of the calculated values, the emissions data pass the evaluation checks related to summary values and are permitted to be submitted to the EPA Host System. (The tolerances can be viewed in the Cross Checks Table document which can be accessed from here.)

The reported values which are submitted to the EPA Host System become the EPA accepted values. Subsequent quarters will use these EPA accepted values for checking the reported Year to Date values. These EPA accepted values can be viewed in the Emission Summary Report in the Emissions module of the Client Tool.

Now back to the questions which some sources are asking. In some cases sources are finding that they may have been incorrectly calculating quarterly and YTD summary values throughout the previous quarters in the year. When they get to 2008Q4, the YTD summary value that EPA calculates through the Client Tool is different enough from the reported value that an evaluation error is given.

The solution could be to resubmit previous quarters with the corrected summary value data. However, that may not be necessary. Instead, sources can simply modify the 2008Q4 emissions data to report the correct YTD value. What is the correct YTD value to report? It would be summing up all of the EPA accepted summary values from previous quarters in the year and adding the reported 2008Q4 summary value.

Ideally, this could be done through the DAHS. Practically, it may require editing the emissions XML file by hand. Sources should work with their DAHS vendor to determine the best way to do this.

Now, if it turns out that problem was not simply a rounding issue or small deviations from the tolerance in each quarter then it may be necessary for a source to resubmit previous quarters' emissions data. Any questions about this should be directed to technical support.