Clean Water Act discharge permit · NPDES MDG870198
CONSTELLATION ENERGY GENERATION LLC HARFORD CONOWINGO HYDROELECTRIC PLANT, Darlington, MD: NPDES MDG870198 discharge permit, effluent exceedances, inspections, penalties
- Administratively continuedPermit status
- MinorDischarger class
- 0Pollutants under a numeric limit
- 0Pollutants with an effluent exceedance
CONSTELLATION ENERGY GENERATION LLC HARFORD CONOWINGO HYDROELECTRIC PLANT, held by EXELON GENERATION CO, LLC, holds NPDES permit MDG870198. EPA’s file records it issued July 26, 2022 and expiring March 31, 2025. The status and dates are as EPA’s permit file stood when Velarion loaded it (September 15, 2026); EPA’s free Detailed Facility Report on ECHO carries the permit’s current standing.
What the register holds for CONSTELLATION ENERGY GENERATION LLC HARFORD CONOWINGO HYDROELECTRIC PLANT: its NPDES ID, its permit type and status, its dates, its address in Darlington, Maryland. EPA’s effluent violation file and its single-event violation file hold no violation for NPDES MDG870198.
Identity
| Facility as filed | CONSTELLATION ENERGY GENERATION LLC HARFORD CONOWINGO HYDROELECTRIC PLANT |
|---|---|
| Permittee as filed | EXELON GENERATION CO, LLC |
| NPDES ID | MDG870198 |
| Permit status | Administratively continued (past its expiration date and still in force until reissued) |
| Permit type | Coverage under a general permit |
| Discharger class | Minor discharger |
| Facility type | Not a publicly owned treatment works |
| Issued | July 26, 2022 |
| Expiration date | March 31, 2025 |
| Issuing agency | MARYLAND DEPARTMENT OF THE ENVIRONMENT |
| Address | Darlington, MD 21034 |
| Receiving water impaired | 303(D) Listed |
| Subwatershed | Rock Run-Susquehanna River (HUC 020503061713) |
Cited to the EPA ICIS-NPDES permit file (ECHO download).
Effluent limits and exceedances
- 0Pollutants on file
- 0Under a numeric limit
- 0With a violation of any kind
- 0With an effluent exceedance
EPA’s limits and effluent violation files hold no pollutant row for NPDES MDG870198.
Cited to the EPA ICIS-NPDES limits and effluent violations files (ECHO download); up to 60 rows shown, most exceedances first.
Inspections, violations and enforcement
- 0Single-event violations
EPA’s single-event violation file, as loaded, holds no violation for NPDES MDG870198.
Velarion’s copy of EPA’s ICIS-NPDES files does not include the inspections, formal enforcement actions and informal enforcement actions files, so this page shows none of them. EPA’s free Detailed Facility Report on ECHO lists this permit’s inspections, enforcement actions and penalties.
Cited to the EPA ICIS-NPDES violation, inspection and enforcement files (ECHO download); up to 50 rows of each shown, newest first.
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EPA publishes a free Detailed Facility Report for every permit on ECHO: its compliance status quarter by quarter, its inspections, and its enforcement actions and penalties. EPA also sends free notices of new inspections and enforcement actions through ECHO Notify; enter NPDES ID MDG870198 there.
Nearby on the register
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- Every permit record in Maryland, A to Z
Figures from EPA’s ICIS-NPDES download, loaded September 15, 2026.