Clean Water Act discharge permit · NPDES MDG490457

LAUREL HILL QUARRY, Laurel, MD: NPDES MDG490457 discharge permit, effluent exceedances, inspections, penalties

EffectivePermit status
MinorDischarger class
7Pollutants under a numeric limit
2Pollutants with an effluent exceedance

LAUREL HILL QUARRY, held by Comus Mining Company, LLC, holds NPDES permit MDG490457, which discharges to Israel'S Creek-Upper Monacacy River. EPA’s file records it issued July 30, 2018 and expiring April 30, 2022. 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	LAUREL HILL QUARRY
Permittee as filed	Comus Mining Company, LLC
NPDES ID	MDG490457
Permit status	Effective
Permit type	Coverage under a general permit
Discharger class	Minor discharger
Facility type	Not a publicly owned treatment works
Issued	July 30, 2018
Expiration date	April 30, 2022
Issuing agency	Maryland Department of The Environment
Address	Laurel, MD 20725
Receiving water	ISRAEL'S CREEK-Upper Monacacy River
Subwatershed	Carroll Creek-Monocacy River (HUC 020700090606)
SIC	3281 – Cut Stone And Stone Products
Other EPA IDs (FRS)	RCRA handler MDD041952946; ICIS-AIR source MD0000002402100003

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

9Pollutants on file
7Under 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
Temperature, water deg. fahrenheit	5	275	6	September 30, 2007	7% over the limit
Solids, total suspended	22	720	2	September 30, 2004	113% over the limit
Flow, in conduit or thru treatment plant	18	770	0
pH	18	690	0
pH change [range]	10	508	0
Solids, settleable	5	263	0
Temp. diff. between up/down stream deg. F	5	254	0
Temp. difference, summer [deg. F]	0	8	0
Temperature, summer [deg. F]	0	8	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 MDG490457.

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 MDG490457 there.

Nearby on the register

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

This public-records page covers Clean Water Act NPDES permit MDG490457 for LAUREL HILL QUARRY in Laurel, MD, held by Comus Mining Company, LLC, which discharges to ISRAEL'S CREEK-Upper Monacacy River in the Carroll Creek-Monocacy River subwatershed (HUC 020700090606). The permit is listed as Effective with a minor discharger class, issued July 30, 2018 and expiring April 30, 2022, with 7 pollutants under a numeric limit and 2 pollutants with an effluent exceedance.