Inventory Selection
Inventory selection is the process of identifying emissions inventory data for inclusion in the General Purpose Release, based on a combination of prioritization algorithms and selections by the inventory developers from the EPA Emissions Inventory and Analyst Group (EIAG). EIAG is responsible for developing and maintaining the NEI and provides analysts and interpretations of emissions data and trends.
During the inventory analysis period, the EPA EIAG team will select data for inclusion in the NEI. The NEI will contain a single emission value for each pollutant for a given source and will be developed by EPA based on data selected to represent a set of emission values most appropriate for use by the general public. There may be further EPA updates, as well as opportunities for S/L/Ts to modify their data after the initial release is published.
During these periods, EPA has access to all submitted data and will run additional analysis checks to identify outliers and other anomalies. EPA will communicate with S/L/Ts where additional data are expected to be reported to fill gaps using calculated data. After resubmission, further analysis checks are run before the General Purpose Release is prepared for publication.
The Inventory Selection functions available on the EIS Gateway provide the Inventory Developers a method to merge information from multiple datasets that may have overlapping data on a per emissions process-pollutant and save the results to a data set. EPA can generate and customize new selection definitions, modify or delete selection criteria and schedule a selection to run from the Gateway’s Inventory Selection tools.
Selection Definition List
The selection definition list displays all of the existing Selection Definitions.
Clicking on a Selection Identifier will display the details about the selection on the Selection Details page
The links in the Selection Definition section permit Inventory Selectors to edit a selection definition, edit selection criteria, or delete a selection definition.
The Selection Criteria section will display the data category of the selection; when a selection was last generated, and a link to schedule the selection; and any data exclusion rule that have been applied to the selection.
Edit Selection Definition
Clicking on the Edit Selection Definition link from the Selection Details page will allow and Inventory Selector to update any details pertaining to the selection including choosing to exclude tagged values and selecting a different output dataset.
Edit Selection Criteria
Clicking on the Edit Selection Criteria link from the Selection Details page will allow an Inventory Selector to update any details pertaining to the selection.
On the Edit Selection Criteria page, choose your selection data sets by dragging and dropping a dataset from the data set list on the left to any of the data category data set boxes. Then click Save at the bottom of the page. Click on the red X to move the dataset back to the main dataset list. You must have at least one dataset listed in one dataset in order to be able to save the selection data set and View the available rules to apply to the selection process. Click on the Save and View Rules to determine any exclusion rules to apply.
Exclusion by Rule
Some data may be removed from a selection based on a set of rules set by the EPA Emissions Inventory and Analysis Group. The pre-defined rules will remove selected data based on certain criteria or you may also run a selection without applying any of the rules, however rules are applied to selections by default. You are also not able to see what data was removed due to an exclusion by rule. There are different rules depending on the dataset type and different rules can be apply to specific data categories. Events selections are based on the “Annual” values, but the Daily values that composed those annual values are created and associated with the selection data set.
The Exclusion by Rules include the following:
- This rule is used by all data categories.
- Some Pollutants Have a “Parent – Child” Relationship to Each Other. These Are Called “Pollutant Groups”. Counting Both a “Parent” and “Child” From a Pollutant Group Would Create Double-Counting.
- If Parent and Child Pollutants from the Same Pollutant Group are Reported to the Same Process, the Selection Will See How the Highest Ranking Data Set Reported Pollutants, and Remove Any Other Pollutants From Different Data Sets That Are Not at the Same “Level” as the Highest Ranking Data Set.
Pollutant Grouping Rule
- Used only by the Nonpoint Data Category.
- If an Agency Says “We Don’t Have Data for This Source”, Delete Any Data for Those SCCs.
- If an Agency Says “Supplement Only for Reported Locations”, Delete Any Data Outside of Location Reported by the Responsible Agency.
Nonpoint Survey Rule
- Used only by the Nonpoint Data Category
- Looks to See How the Highest Ranking Data Set Reported the Data and Then Backfills with Other Data Sets That Reported at the Same “Level”.
Option Group/Option Set Rule
- Applies Only to Point Data Category.
- Some data sources EPA uses aggregate the data to a Facility-Level summary, therefore, there may be some overlaps.
- This rule deletes data from lower hierarchy datasets If the following criteria are met:
- They belong to the same facility.
- They are measuring the same pollutant.
- At least one of the datasets is aggregated to the facility level. This is a property of the dataset and controlled by EIS Content Managers.
Facility Group Rule
Delete Selection Definition
Click on Delete Selection Definition if you want to permanently remove a selection definition.
Selection Overrides
Inventory Developers can modify the default hierarchy of a selection to be overridden based on values of the attributes of the process or pollutant, thus allowing for a customized hierarchy to be enforced. The override feature is usually used to exclude pollutants from the selection
- State
- County
- Tribe
- Sector
- Facility Source Type
- SCC
- Pollutant Code
Overrides Can be Based on the following criteria (Shown in Reverse Priority Order):
Selection Override
Clicking Add Override link navigates to “Add Selection Override” page. Then select from the Override types to update the selection hierarchy.
In demonstrating the navigation, we will select “State.”
Next select the State Override accordion to expand the list of states to select from.
Select the State you want to override in the Selection.
If you want to modify the priority of the Override in the Selection, before clicking Save, click on the Override Priority accordion. The accordion will expand and you are able to drag and drop datasets into the Selection Override Priority box to create the prioritization hierarchy for the datasets.
Schedule Selection Generation
A selection can be scheduled to run from the Selection Criteria section of the Selection Details page. Click on the “Schedule for Generation” link to put the selection job in the queue. The Last Generated On date will be displayed after the selection has run. Selections are scheduled to run as an overnight job every 24 hours.
