Clean Water Act discharge permit · NPDES MA0003557

PILGRIM NUCLEAR POWER STATION, Plymouth, MA: NPDES MA0003557 discharge permit, effluent exceedances, inspections, penalties

Administratively continuedPermit status
MajorDischarger class
6Pollutants under a numeric limit
4Pollutants with an effluent exceedance

PILGRIM NUCLEAR POWER STATION, held by HOLTEC PILGRIM, holds NPDES permit MA0003557, which discharges to Cape Cod Bay. EPA’s file records it issued April 29, 1991 and expiring April 29, 1996. The status and dates are as EPA’s permit file stood when Velarion loaded it (October 14, 2026); EPA’s free Detailed Facility Report on ECHO carries the permit’s current standing.

Identity

Facility as filed	PILGRIM NUCLEAR POWER STATION
Permittee as filed	HOLTEC PILGRIM
NPDES ID	MA0003557
Permit status	Administratively continued (past its expiration date and still in force until reissued)
Permit type	Individual permit
Discharger class	Major discharger
Facility type	Not a publicly owned treatment works
Issued	April 29, 1991
Expiration date	April 29, 1996
Address	Plymouth, MA 02360
Receiving water	CAPE COD BAY
Subwatershed	Great Herring Pond-Frontal Cape Cod Bay (HUC 010900020107)
NAICS	221113 – Nuclear Electric Power Generation
SIC	4911 – Electric Services
Other EPA IDs (FRS)	RCRA handler MAR000014167

Cited to the EPA ICIS-NPDES permit file (ECHO download) and EPA’s NAICS/SIC and component files, the same download; cross-program IDs from EPA’s FRS facility-registry crosswalk.

Effluent limits and exceedances

7Pollutants on file
6Under a numeric limit
7With a violation of any kind
4With an effluent exceedance

An effluent exceedance is a discharge monitoring report value over the permit’s numeric limit (EPA’s violation code E90). A violation of any kind also counts a report not filed. Each row is EPA’s own count for that pollutant.

Pollutant or measure	Limits	Violations, any kind	Effluent exceedances	Latest exceedance	Largest exceedance, as filed
Solids, total suspended	10	80	38	July 31, 2026	2,770% over the limit
Oxidants, total residual	4	19	15	February 28, 2013	400% over the limit
Temp. diff. between intake and discharge	1	8	6	March 31, 2002	6% over the limit
Temperature, water deg. fahrenheit	2	20	1	October 31, 1995	3% over the limit
Oil & Grease	8	47	0
Flow, in conduit or thru treatment plant	12	7	0
pH	0	2	0

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 MA0003557.

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 MA0003557 there.

Nearby on the register

Figures from EPA’s ICIS-NPDES download, loaded October 14, 2026.

This public-records page covers Clean Water Act discharge permit NPDES MA0003557 for Pilgrim Nuclear Power Station in Plymouth, MA, held by HOLTEC PILGRIM, which discharges to Cape Cod Bay and is listed as administratively continued and a Major Discharger. The page lists 6 in the discharger class, 4 pollutants under a numeric limit, and 4 pollutants with an effluent exceedance. The facts were loaded on October 14, 2026, and the permit's recorded issue and expiration dates are April 29, 1991 and April 29, 1996.