Permit Limit Sets and Limits
Limits specify permit wastewater discharge monitoring requirements and effluent limits. Before limits can be added to a permit, a feature must be added to the permit. Limit sets and limits are then added to the permitted features. Limit sets and limits drive the generation of Discharge Monitoring Reports (DMRs) that a permittee is required to submit as a condition of their permit.
Limit sets and limits can only be modified while a permit is in In Process status. When a permit status is updated to Issued/In Effect, the expected DMRs are generated based on the limit sets and limits that have been entered. Limits are no longer changeable at that point.
If you do not see the Limits tab on the permit, this is configured in the Permit Categories lookup, under Permit Feature Display Mode.
Limit Sets
Overview
Limit sets define the period of time covered by Discharge Monitoring Reports (DMR) and the date on which DMRs begin for a permit. A limit set can relate to multiple permitted features, which can be helpful when defining limits for permits that contain a large number of outfalls. Limit sets contain one or more monitoring requirements or effluent limits. For example, a limit set may indicate that a permittee must submit a monthly report containing sampling data for outfall number 001.
Limit sets are typically used to group sampling requirements based on monitoring frequency at an outfall (e.g., monthly, bi-monthly, quarterly, annually, etc.), but also can be used to group limits that must be reported under different operating conditions. For example, a facility may have two different sets of effluent limits at an outfall based on data that may vary from month to month, such as factory production output or receiving stream flow. In a case like this, typically called tiered limits, a limit set can be set up to represent each condition. The permittee would fill out the DMR for the limit set that applied for that period and would report No Discharge for the limit set that did not apply.
Adding and Editing Limit Sets
Limit Sets and Limits can only be added, modified, or deleted if the permit is in ‘In Process’ status and the current user has rights to edit the permit. Limit sets may also be deleted if the set is associated with a prior permit version.
On the Limits tab of the Permit Details screen, one of the following actions may be taken:
Click the Add Limit Set button to add a new limit set.
Click the Copy Limit Set button to copy a limit set from a limit set template (see Limit Set Templates), or to copy an existing limit from another permit.
Click the Open button for an existing limit set.
Click the Copy button for an existing limit set to copy it as a new limit.
Fixing Initial Monitoring Dates
A Fix Initial Monitoring Dates button appears if one or more limit sets meet the following conditions:
Limit set is missing an Initial Monitoring Date.
Limit set Initial Monitoring Date would create DMRs for monitoring periods before the current permit version’s effective date.
Limit set’s reporting period is non-monthly (e.g., quarterly, semi-annual, or annual) and does not begin in the expected calendar month. This check is only performed if nVIRO is configured to enable this check.
Click this button to automatically calculate a valid limit set initial monitoring dates. Since situations can vary, make sure to verify that the calculated dates are correct for the given permit.
Controls
When adding or editing a limit set, the following fields are displayed:
Field | Description |
---|---|
Limit Set Name | A short text description of the limit set. This is displayed on the top of a DMR form to help identify the limit set. |
Limit Set Description | A long text description of the limit set. Displayed on the internal Limit Set list page for internal staff to better understand the purpose of a limit set. |
ICIS Limit Set Designator | A one- or two-character identifier is used to uniquely identify the limit set on the permitted feature. This value is suffixed onto the Permit Feature Identifier for display in lists and on the DMR data entry pages. For example, designator “A” on permitted feature “001” would display as limit set “001A”. |
Limit Set Status | Allows for a limit set to transition from Pending to Active and finally, Closed. Limit Sets default to Active status when first created, and the Status Date is synchronized with the Initial Monitoring Date. If a limit set is initially set to Pending status, DMRs will not be created for this limit set when the permit is issued. If the Limit Set Status needs to change after a permit is put into effect, the permit will need to be set back to "In Process" status, after which new statuses can be added. Existing statuses cannot be edited once they have been flowed to ICIS-NPDES. |
Wastewater Types | A list of one or more wastewater types. This list is filtered to only allow selection of the wastewater types assigned to the permitted feature to which the limit set is assigned. This drop-down will not display if no wastewater types have been configured in the system. These values can be configured to be sent to ICIS-NPDES as Permitted Feature Characteristics. This field has no bearing on the creation of DMRs. |
Design Flow or Authorized Flow / Unit | The amount of flow that the wastewater system is designed to process or that is authorized for this limit set. This field has no bearing on the creation of DMRs. |
Conveyance | Text field for describing how the wastewater is conveyed to the receiving stream (e.g., “unnamed ditch”). This field is intended for use in permit document templates to construct a sentence describing how the wastewater reaches a receiving stream. |
Generate DMRs | Checkbox that indicates whether to generate DMRs for this limit set. If the facility is allowed to perform retained self-monitoring (RSM), then uncheck this box. If unchecked, the limit set and associated limits will not flow to ICIS-NPDES. |
Scheduled | Checkbox that indicates whether the DMR is scheduled or unscheduled. Most limit sets are scheduled, indicating that DMRs should be generated at a regular, predictable frequency. Unscheduled limit sets are for event-based DMR reporting that occurs unpredictably. An example would be a bypass caused by a rain event. If one or more unscheduled limit sets exist on a permit, users will have the option to submit an unscheduled DMR on the DMR List page. When selected, the user will be prompted to select from a list of available unscheduled limit sets. |
Monitoring Period | Indicates the period of time covered on each generated DMR form. |
Reporting Period | Indicates how often DMRs must be submitted. The selected frequency must be less than or equal to the monitoring period and must be equally divisible by the monitoring period. It is recommended that the reporting period be set to be the same as the monitoring period. Varying reporting periods was a feature that was useful when DMR reporting was performed on paper because it simplified the mailing requirements for the permittee, but with electronic reporting, this option is less useful since all data is collected online. |
First DMR Begin Date | The begin date of the first (earliest) DMR in the limit set. For non-monthly limit sets (quarterly, semi-annual, etc.), this date selects the cadence for all future DMR periods. For example, if the first DMR Begin Date of a limit set with quarterly monitoring frequency is in February, the generated DMRs will be in February, May, August, and November each year. For this reason, it is very important to ensure that the initial monitoring date is set correctly. If the intent is for quarterly DMRs to fall on regular calendar quarters, the First DMR Begin Date must begin in January, April, July, or October. This is true even if the limits in the limit set do not start in one of these months. |
Days from Report End Date When Due | Indicates the grace period between the end of a DMR monitoring period and when the DMR is due. For example, if the DMR is due 15 days after the end of each monitoring period, then the value 15 should be entered. Note that DMRs will show as late when the due date comes to pass. NOTE: nVIRO can be set up to not calculate late DMR violations until some period after the due date. For agencies that still receive paper, this can provide a buffer for the agency to finish data entry before late violations are generated. |
Applicable Months | Indicates the months that limits within the limit set apply. The selected months serve as the default selected months when adding new limits to the limit set. This is provided as a time-saving convenience feature. Limit months can always be manually changed on each limit. |
Special Instructions | Instructions displayed on the DMR Data Entry form. This should be used to describe any limits where a “See Comments” monitoring location has been added or any other time when instructions should be provided to the external user about how to fill out the DMR. |
Limits
Overview
Limits include monitoring requirements and effluent limits. Limits are added to a Limit Set and define the parameters that display on DMR forms. Each limit consists of a parameter (substance or condition to be measured), a monitoring location (indicating where the sample should be taken, or other special condition), and one or more limit values.
The standard EPA DMR Summary form defines up to five different limits for a given parameter, grouped by quantity and concentration. The five-column format provides a compact way of presenting a data entry interface for either paper or page. A parameter needs only one limit to be entered in one of the five available columns in order to be saved.
Adding and Editing Limits
On the Limits tab, one of the follo