Clean Water Act discharge permit · NPDES MD0002763

LOCKE INSULATORS, INC., Baltimore, MD: NPDES MD0002763 discharge permit, effluent exceedances, inspections, penalties

Administratively continuedPermit status
MinorDischarger class
9Pollutants under a numeric limit
2Pollutants with an effluent exceedance

LOCKE INSULATORS, INC. holds NPDES permit MD0002763, which discharges to Middle Branch, Patapsco River. EPA’s file records it issued August 30, 2011 and expiring September 30, 2016. 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.

Identity

Facility as filed	LOCKE INSULATORS, INC.
Permittee as filed	LOCKE INSULATORS, INC.
NPDES ID	MD0002763
Permit status	Administratively continued (past its expiration date and still in force until reissued)
Permit type	Individual permit
Discharger class	Minor discharger
Facility type	Not a publicly owned treatment works
Issued	August 30, 2011
Expiration date	September 30, 2016
Issuing agency	Maryland Department of the Environment
Address	Baltimore, MD 21230
Receiving water	MIDDLE BRANCH, PATAPSCO RIVER
Receiving water impaired	303(D) Listed
Subwatershed	Northwest Harbor-Patapsco River (HUC 020600031203)
Other EPA IDs (FRS)	RCRA handler MDD064874712; ICIS-AIR source MD0000002451000306

Cited to the EPA ICIS-NPDES permit file (ECHO download); cross-program IDs from EPA’s FRS facility-registry crosswalk.

Effluent limits and exceedances

9Pollutants on file
9Under a numeric limit
9With a violation of any kind
2With 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	4	29	9	February 28, 2017	90% over the limit
pH	4	21	3	March 31, 2009
Flow, in conduit or thru treatment plant	6	19	0
Chlorine, total residual	4	12	0
Turbidity	2	8	0
Nitrogen, nitrite total [as N]	4	6	0
Nitrogen, nitrate total [as N]	4	6	0
Nitrogen, Kjeldahl, total [as N]	4	6	0
Nitrogen, total [as N]	4	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 MD0002763.

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 MD0002763 there.

Nearby on the register

Figures from EPA’s ICIS-NPDES download, loaded September 15, 2026.

This public-records page covers Clean Water Act discharge permit NPDES MD0002763 held by LOCKE INSULATORS, INC. in Baltimore, MD, which discharges to Middle Branch, Patapsco River, and is administratively continued as a Minor Discharger with 9 pollutants under a numeric limit and 2 pollutants with an effluent exceedance. The permit was issued August 30, 2011 and expired September 30, 2016, with its status as of September 15, 2026, and the watershed is listed as HUC 020600031203.