Master Research & Manufacturing Inc

Active WDID 4 19I031312 Norwalk, Los Angeles County Region 4 · Los Angeles

At a glance

Permit Evidence: SMARTS record
Active Industrial
Notice of Intent (WDID code I) · Permits and applications
Location Evidence: facility-reported
Norwalk, Los Angeles County
Region 4 · Los Angeles · Location · Statewide map
Receiving water
Coyote Creek (as reported by the facility)
Evidence: candidate, awaiting review Details
Identified receiving water on the 2026 303(d) list
Not established
Shown only when the reported receiving water is identified and corroborated.
2026 Integrated Report waters within 1.0 km Evidence: geographic proximity
1 waterbody; 1 on the 2026 303(d) list
Proximity only; not a discharge pathway · Nearby waterbodies
Monitoring results Evidence: facility-reported
15 distinct results, 1 reporting year (2025 to 2025)
Most recent sample Feb 16, 2026 · Monitoring
Compliance and enforcement records Evidence: SMARTS record
0 inspections · 0 violation records · 0 enforcement actions
Counts as published in SMARTS; not a compliance determination · Details
SMARTS TMDL records Evidence: SMARTS-reported
0 records
TMDL records

Each label shows where a statement comes from. How to read the labels.

Overview and location

Reported facility location HUC12 watershed Corroborated receiving water 2026 Integrated Report waterbodies nearby

Open this facility on the statewide map

Reported location Evidence: facility-reported

Coordinates
33.89733, -118.04303
Precision
5 decimal places
Shared point
2 permits report this exact point
Matches application record
same

Facility location as reported by the discharger in SMARTS; not a discharge point or outfall.

Facility address
13528 Pumice St, Norwalk 90650
Regional Water Board
4 — Los Angeles

HUC12 watershed Evidence: spatial

  • La Mirada Creek HUC12 180701060602

The facility's reported location lies within this HUC12 watershed (spatial derivation); it is not a discharge location.

Permits and applications Evidence: SMARTS record

Current permit record

Permit type
Industrial
Application type
Notice of Intent (WDID code I)
Status
Active
Operator
Master Research & Manufacturing
Primary industry (SIC)
3728-Aircraft Parts and Auxiliary Equipment, NEC
Application ID
592136
NOI processed
Oct 27, 2025
Last certified
Oct 21, 2025
Facility size
57000 SqFt
Impervious area
100 %

Retrieved from SMARTS Oct 20, 2026. Verify against SMARTS before relying on it.

Permit history

Storm water applications for this WDID, newest first
ApplicationTypeStatusProcessedTerminatedCertified
592136 IndustrialActiveOct 27, 2025 —Oct 21, 2025

Every storm water application SMARTS records for this WDID, newest first (1).

Receiving water

Reported by the facility Evidence: facility-reported
Coyote Creek
Discharges directly / indirectly
N / Y (as answered in the permit application)

Evidence: not confirmed Evidence: candidate, awaiting review Awaiting review

Receiving-water text as reported by the discharger in SMARTS; no waterbody identification has been confirmed.

Why it is not confirmed (1)
  • C3 facility HUC12 not corroborated (complete published list)

1 official waterbody shares this name; none is assigned without review.

Impaired waters and TMDLs

Two kinds of information, kept apart: 2026 Integrated Report waterbodies near the reported location (geographic proximity only), and TMDL records that SMARTS lists for this facility. Neither establishes where the facility discharges; see Receiving water for the facility's own statement.

Nearby waterbodies Evidence: geographic proximity

Spatial proximity only; discharge pathway not established. Being near a waterbody does not mean the facility discharges to it.

Nearest 2026 Integrated Report waterbodies
Waterbody (2026 Integrated Report)Distance2026 303(d) listAppendix A decisions
Coyote Creek, North Fork CAR4051501020081117111917360 m listed4

Waterbodies within 1.0 km of the reported facility location. Method proximity/1.

SMARTS TMDL records Evidence: SMARTS-reported

No TMDL records for this facility in the SMARTS TMDL export.

Reported monitoring results Evidence: facility-reported

Numeric Action Level (NAL) screening is being independently validated and is not shown. Nothing on this page states whether a result exceeded a NAL.

15 distinct measurements across 5 parameters, most recent sample Feb 16, 2026.

By reporting year

Distinct results by reporting year
Reporting year (July–June)Distinct resultsParametersWith several versionsFirst sampleLast sample
2025155 0 Nov 14, 2025Feb 16, 2026

By parameter

Distinct results by parameter
ParameterUnitsMeasurementsBelow detectionFirst sampleLast sampleResults
Aluminum, Totalmg/L3 0Nov 14, 2025Feb 16, 2026 Results
Iron, Totalmg/L3 1Nov 14, 2025Feb 16, 2026 Results
Oil and Greasemg/L3 3Nov 14, 2025Feb 16, 2026 Results
pHSU3 0Nov 14, 2025Feb 16, 2026 Results
Total Suspended Solids (TSS)mg/L3 0Nov 14, 2025Feb 16, 2026 Results

All results (15 distinct rows)

Reported monitoring results, newest first
Sample dateParameterResultUnitsLocation typeEventMethodReportVersions
Feb 16, 2026 Aluminum, Total 2.97 mg/L Effluent Qualifying Storm Event E200.8 1374006
Feb 16, 2026 Iron, Total 1.8 mg/L Effluent Qualifying Storm Event E200.7 1374006
Feb 16, 2026 Oil and Grease < 5 mg/L Effluent Qualifying Storm Event E1664A 1374006
Feb 16, 2026 pH 7 SU Effluent Qualifying Storm Event pH_Paper 1374006
Feb 16, 2026 Total Suspended Solids (TSS) 31 mg/L Effluent Qualifying Storm Event A2540D 1374006
Dec 24, 2025 Aluminum, Total .954 mg/L Effluent Qualifying Storm Event E200.8 1370920
Dec 24, 2025 Iron, Total .7 mg/L Effluent Qualifying Storm Event E200.7 1370920
Dec 24, 2025 Oil and Grease < 5 mg/L Effluent Qualifying Storm Event E1664A 1370920
Dec 24, 2025 pH 7 SU Effluent Qualifying Storm Event pH_Paper 1370920
Dec 24, 2025 Total Suspended Solids (TSS) 46 mg/L Effluent Qualifying Storm Event A2540D 1370920
Nov 14, 2025 Aluminum, Total .022 mg/L Effluent Qualifying Storm Event E200.8 1367029
Nov 14, 2025 Iron, Total < .08 mg/L Effluent Qualifying Storm Event E200.7 1367029
Nov 14, 2025 Oil and Grease < 5 mg/L Effluent Qualifying Storm Event E1664A 1367029
Nov 14, 2025 pH 7 SU Effluent Qualifying Storm Event pH_Paper 1367029
Nov 14, 2025 Total Suspended Solids (TSS) 12 mg/L Effluent Qualifying Storm Event A2540D 1367029

Results are shown exactly as reported by the discharger. Identical rows repeated in the State's export are shown once. Where the export contains different versions of the same sample and parameter, each version is listed and flagged. Details.

Compliance and enforcement records Evidence: SMARTS record

These are records as the State Water Board publishes them in SMARTS, with the source's own types and statuses. They are not a compliance determination or rating. A record listed here is not proof of a violation beyond what the source states, and the absence of records does not establish compliance.

Compliance and enforcement records by type
Record typeRecordsAs publishedDatesRetrievedList
Violations0 0 Violation · 0 Potential (preliminary) · 0 Dismissed — Oct 21, 2026
Enforcement actions0 0 issued · 0 draft · 0 withdrawn, rescinded or superseded — Oct 21, 2026
Inspections0inspections, not findings — Oct 21, 2026
Annual reports1certified reports (contents not shown) 2025 – 2025 Oct 21, 2026 All reports
Water-quality-based corrective action reports0reports, by parameter — Oct 21, 2026

Each record type is counted by its own SMARTS identifier. A violation and the enforcement action that cites it are two records in two lists; they are never added together.

Chronological record history (1 records, newest first)
Compliance and enforcement records, newest first
DateRecordIDType or purposeStatus as publishedDetail
Jun 29, 2026 Annual reports 1354596 Annual report 2025 —

Sources and provenance

Sources behind this page
InformationSourceRetrieved or published
Permit, location, receiving-water textSMARTS Industrial Application Specific DataOct 20, 2026
Permit historySMARTS Storm Water ApplicationsOct 20, 2026
Monitoring resultsSMARTS Industrial Parameter DataOct 20, 2026
Watershed Boundary Dataset HU2 GeoPackages 15, 16, 18 (WBDHU12)USGS2026-10-22
2026 California Integrated Report, Appendix A: 2026 303(d) List (final)SWRCB2026-10-22
Final_2026_Rivers_and_Streams + Final_2026_Lakes_and_Reservoirs (FeatureServer 0)SWRCB GIS2026-10-22
SMARTS TMDL requirementsSMARTS2026-10-21

Relationships computed 2026-10-22 with methods facility_huc12/1, proximity/1, receiving_water/2, tmdl_reference/1, waterbody_huc12_ovl/1, waterbody_huc12_pub/1; proximity threshold 1.0 km.

How to read the evidence labels

Records are shown as published and are not compliance determinations. How geographic context is derived.