Clean Water Act discharge permit · NPDES MDG491365

ROCKVILLE QUARRY & READY MIX CONCRETE, Rockville, MD: NPDES MDG491365 discharge permit, effluent exceedances, inspections, penalties

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

ROCKVILLE QUARRY & READY MIX CONCRETE, held by BARDON, INC. (dba AGGREGATE INDUSTRIES), holds NPDES permit MDG491365, which discharges to Unnamed Trib Ot Potomac River. EPA’s file records it issued December 1, 2011 and expiring April 30, 2015. 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	ROCKVILLE QUARRY & READY MIX CONCRETE
Permittee as filed	BARDON, INC. (dba AGGREGATE INDUSTRIES)
NPDES ID	MDG491365
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	December 1, 2011
Expiration date	April 30, 2015
Issuing agency	Maryland Department of The Environement
Address	Rockville, MD 20850
Receiving water	UNNAMED TRIB OT POTOMAC RIVER
Receiving water impaired	303(D) Listed
Subwatershed	Muddy Branch (HUC 020700081001)
Other EPA IDs (FRS)	RCRA handler MDD009849779; ICIS-AIR source MD0000002403100528

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

Effluent limits and exceedances

8Pollutants on file
4Under a numeric limit
8With 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	2	137	58	February 28, 2026	400% over the limit
pH	2	83	5	March 31, 2007
pH change [range]	2	45	3	December 31, 2012
Solids, settleable	0	32	3	December 31, 2006	160% over the limit
Flow, in conduit or thru treatment plant	2	76	0
Temperature, water deg. fahrenheit	0	25	0
Temp. difference, summer [deg. F]	0	2	0
Temperature, summer [deg. F]	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 MDG491365.

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 MDG491365 there.

Nearby on the register

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

The page is a public-records entry for NPDES permit MDG491365, held by BARDON, INC. (dba AGGREGATE INDUSTRIES) for ROCKVILLE QUARRY & READY MIX CONCRETE, which discharges to UNNAMED TRIB OT POTOMAC RIVER in the Muddy Branch subwatershed (HUC 020700081001). The permit is administratively continued, issued December 1, 2011 and expiring April 30, 2015, and the figures listed are 4 pollutants under a numeric limit and 4 pollutants with an effluent exceedance.