Clean Water Act discharge permit · NPDES MDG492212
ROCKVILLE READY MIX, Rockville, MD: NPDES MDG492212 discharge permit, effluent exceedances, inspections, penalties
- Administratively continuedPermit status
- MinorDischarger class
- 4Pollutants under a numeric limit
- 3Pollutants with an effluent exceedance
ROCKVILLE READY MIX, held by LaFarge Mid Atlantic, Inc., holds NPDES permit MDG492212, which discharges to Rock Creek. 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 (October 14, 2026); EPA’s free Detailed Facility Report on ECHO carries the permit’s current standing.
Identity
| Facility as filed | ROCKVILLE READY MIX |
|---|---|
| Permittee as filed | LaFarge Mid Atlantic, Inc. |
| NPDES ID | MDG492212 |
| 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 Environment |
| Address | Rockville, MD 20850 |
| Receiving water | ROCK CREEK |
| Subwatershed | Upper Rock Creek (HUC 020700100101) |
| SIC | 3273 – Ready-Mixed Concrete |
Cited to the EPA ICIS-NPDES permit file (ECHO download) and EPA’s NAICS/SIC and component files, the same download.
Effluent limits and exceedances
- 5Pollutants on file
- 4Under a numeric limit
- 5With a violation of any kind
- 3With 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 | 124 | 12 | May 31, 2022 | 385% over the limit |
| pH | 4 | 123 | 11 | July 31, 2025 | |
| Oil and grease | 0 | 1 | 1 | April 30, 2020 | 283% over the limit |
| Flow, in conduit or thru treatment plant | 4 | 148 | 0 | ||
| pH change [range] | 4 | 38 | 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 MDG492212.
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 MDG492212 there.
Nearby on the register
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Figures from EPA’s ICIS-NPDES download, loaded October 14, 2026.