Clean Water Act discharge permit · NPDES MA0004928

GENON HOLDCO 10, LLC, Sandwich, MA: NPDES MA0004928 discharge permit, effluent exceedances, inspections, penalties

Administratively continuedPermit status
MajorDischarger class
8Pollutants under a numeric limit
6Pollutants with an effluent exceedance

GENON HOLDCO 10, LLC holds NPDES permit MA0004928, which discharges to Cape Cod Canal. EPA’s file records it issued June 23, 1989 and expiring June 23, 1994. 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	GENON HOLDCO 10, LLC
Permittee as filed	GENON HOLDCO 10, LLC
NPDES ID	MA0004928
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	June 23, 1989
Expiration date	June 23, 1994
Address	Sandwich, MA 02563
Receiving water	CAPE COD CANAL
Subwatershed	Wequaquet Lake (HUC 010900020206)
SIC	4911 – Electric Services
Other EPA IDs (FRS)	RCRA handler MAD071708929; ICIS-AIR source MA0000002512000054

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

8Pollutants on file
8Under a numeric limit
8With a violation of any kind
6With 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
Temperature, water deg. fahrenheit	2	100	94	June 30, 2026	37% over the limit
Iron, total [as Fe]	2	16	11	March 31, 2000	205% over the limit
Flow, in conduit or thru treatment plant	9	22	5	July 31, 2003	642% over the limit
pH	10	26	4	January 31, 2000
Solids, total suspended	4	11	2	September 30, 1993	35% over the limit
Copper, total [as Cu]	2	6	2	November 30, 1997	200% over the limit
Oil & Grease	5	7	0
Chlorine, total residual	1	4	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 MA0004928.

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.

Watch this permit

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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 MA0004928 there.

Nearby on the register

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

This public-records page covers NPDES permit MA0004928, held by GENON HOLDCO 10, LLC in Sandwich, MA, which discharges to the Cape Cod Canal and is administratively continued as a major discharger. The figures listed are 8 pollutants under a numeric limit and 6 pollutants with an effluent exceedance.