Methodology

Last Updated: April 10, 2026

Data Source

All data on PermitMinder is sourced from the Pennsylvania Department of Environmental Protection's electronic Discharge Monitoring Report (eDMR) public records system. These are self-reported monitoring results that NPDES-permitted facilities are required to submit to PA DEP under the federal Clean Water Act.

Public eDMR data is available through PA DEP's website: PA DEP eDMR Program

Update Cadence

We refresh our copy of the PA eDMR dataset on a regular schedule. The most recent refresh date is shown in the footer of every page ("Data last updated"). Because facilities report on monthly or quarterly cycles, the most recent monitoring period in our database typically lags real-world discharge activity by 30–90 days. This lag is a function of how PA DEP receives and publishes the underlying reports, not of our refresh cadence.

How Exceedances Are Calculated

An exceedance on PermitMinder is defined as a single reported monitoring value that is greater than the numeric limit set by the facility's NPDES permit for that parameter, outfall, and monitoring period.

In plain terms, for each row in a facility's eDMR submission we compare:

  • the reported value (the number the facility submitted to PA DEP), and
  • the permit limit (the numeric ceiling, floor, or average specified in the facility's active NPDES permit for that parameter).

When the reported value is outside the permitted range, we flag the row as an exceedance. We do not apply statistical smoothing, rolling averages, or weighting across periods. Each exceedance on the site corresponds to a specific row of public eDMR data that you can verify against PA DEP's system.

Parameters with non-numeric limits (e.g., narrative standards, monitor-only requirements, or "report" limits) are excluded from exceedance counts because there is no numeric threshold to compare against.

Exceedance vs. Violation

An exceedance is not the same thing as a violation, and PermitMinder does not determine violations.

A violation is a legal conclusion. Only the U.S. Environmental Protection Agency, the Pennsylvania Department of Environmental Protection, a court, or another body with enforcement authority can determine whether a particular exceedance constitutes a violation of the Clean Water Act or of a facility's NPDES permit. That determination depends on factors beyond the raw eDMR data, including upset and bypass provisions, compliance schedules, administrative orders, consent decrees, and enforcement discretion.

An exceedance, as we use the term, is a purely arithmetic observation: a reported value was higher than the permit limit on a given day. We report exceedances as facts drawn from public records. We do not characterize them as violations, we do not predict enforcement outcomes, and we do not rank or score facilities based on their exceedance history.

Consecutive Exceedance Months

On facility detail pages, PermitMinder displays a "Consecutive Exceedance Months" statistic for each parameter. This is the number of sequential calendar months in which a parameter's reported value exceeded its permit limit without interruption, counted up to the most recent monitoring period available.

This metric is shown to help users identify persistent patterns in publicly reported discharge monitoring data. A long streak may indicate that a parameter has been consistently reported above its permitted limit over multiple reporting periods.

Consecutive exceedance months is a descriptive statistic derived from publicly reported DMR data. It is not an enforcement indicator, a compliance score, or a legal determination. Whether any exceedance or pattern of exceedances constitutes a permit violation is a question that only EPA, PA DEP, or a court can answer. PermitMinder does not make that determination.

Known Data Gaps and Limitations

  • Coverage. PermitMinder currently covers Pennsylvania eDMR data only. Facilities permitted in other states are not included.
  • Self-reported data. eDMR submissions are prepared by the permittees themselves. PermitMinder does not independently verify the accuracy of reported values.
  • Permit limit changes. Permits are renewed, modified, and reissued over time. Historical exceedances are compared against the limit in effect at the time of the reported value to the extent that information is available in the source data.
  • Reporting lag. As noted above, the most recent monitoring period in our database typically lags current discharge activity by 30–90 days because of PA DEP's publication cycle.
  • Data entry and transcription errors. The source dataset occasionally contains clerical errors (unit mismatches, decimal shifts, duplicated rows). When we identify obvious errors we document them; otherwise we display the data as published.
  • Non-numeric parameters. Parameters without numeric permit limits are displayed on facility pages but are not included in exceedance counts.

Corrections

If you believe a specific record on PermitMinder is inaccurate or misrepresents the underlying PA DEP data, contact permitminder@gmail.com with the facility name, parameter, and monitoring period, and we will review.