← Facilities

Industrial stormwater facility

Royal Gold LLC

WDID 1 12I025790 · Notice of Intent · Arcata, Humboldt

SIC 2875 · Fertilizers, Mixing Only · Regional Board 1 - North Coast Region

Official record — State Water Resources Control Board, Industrial General Permit

Hydrologic

Geographic context

Official facility coordinate plotted against the associated Final 2026 Integrated Report impaired-water geometry.

Loading map…
  • Facility location (official coordinate)
  • Associated impaired-water geometry (Final 2026 Integrated Report)
  • YDOS-derived geographic context
  • Loading associated geometry…

Geometry shown is limited to waterbodies geographically associated with this facility. Geographic association does not establish a discharge connection, receiving-water connectivity, or causation.

Official facility point
40.90084, -124.02214
HUC12 subwatershed
Mill Creek-Mad River
HUC12 code
180101020408
Impaired-water associations (derived)
1

Official

Facility record

Facility name
Royal Gold LLC
WDID
1 12I025790
Application type
Notice of Intent
City
Arcata
County
Humboldt
ZIP
95521
Primary SIC code
2875
SIC description
Fertilizers, Mixing Only
Date active
2015-07-07
Regional Water Board
Regional Board 1 - North Coast Region

303(d) context

Associated impaired waters

Grouped by derived geographic association class.

Derived

Subwatershed + nearby

1 waterbodies
Mad River HU, Mad River

River & Stream · Integrated Report category 5 · TMDL required

Listed pollutants / stressors (6) Aluminum, Sediment, Sedimentation/Siltation, Specific Conductivity, Temperature, water, Turbidity

Distance 0.31 km

Confidence high

Fact sheet

Associations are calculated from official facility coordinates, USGS HUC12 boundaries, and official 2026 impaired-water geometry. They do not establish a discharge connection or causation.

TMDL requirements

Water Board-stated TMDL waste load allocations applied to this industrial permit in SMARTS.

Official record — SMARTS TMDL dataset, State Water Board

No SMARTS TMDL requirement is recorded for this WDID. In the statewide TMDL export only permits in Regions 4, 8 and 9 currently carry industrial TMDL requirements, so an absence here is not a statement that the facility discharges to an unimpaired water.

Official monitoring

SMARTS monitoring

Self-reported industrial stormwater sampling results as submitted by the discharger to SMARTS.

Official record — SMARTS parameter data, State Water Board
Reported results
2,118
Sample events
200
Distinct parameters
13
Reporting years
2015 – 2025
First sample
2015-11-09
Latest sample
2026-04-01
Source regional dataset
Region 1 - North Coast
Source retrieved
Aug 21, 2026

Official SMARTS public reports

Parameters reported

Reported results over time

Loading reported results…

Most recent reported results

Latest 25 of 2,118
Sample dateLocationParameterResultUnitsEvent
2026-04-01DP-1Chemical oxygen demand (COD)22mg/LQualifying Storm Event
2026-04-01DP-1Iron.41mg/LQualifying Storm Event
2026-04-01DP-1LeadND (non-detect / est.)mg/LQualifying Storm Event
2026-04-01DP-1Nitrate2.7mg/LQualifying Storm Event
2026-04-01DP-1Nitrate/Nitrite (Nitrite + Nitrate as N)2.7mg/LQualifying Storm Event
2026-04-01DP-1Nitrogen, NitriteND (non-detect / est.)mg/LQualifying Storm Event
2026-04-01DP-1Oil and GreaseND (non-detect / est.)mg/LQualifying Storm Event
2026-04-01DP-1pH7.6SUQualifying Storm Event
2026-04-01DP-1Phosphorus.14mg/LQualifying Storm Event
2026-04-01DP-1Total Suspended Solids (TSS)5.9mg/LQualifying Storm Event
2026-04-01DP-1Zinc.027mg/LQualifying Storm Event
2026-04-01DP-2Chemical oxygen demand (COD)13mg/LQualifying Storm Event
2026-04-01DP-2Iron.55mg/LQualifying Storm Event
2026-04-01DP-2LeadND (non-detect / est.)mg/LQualifying Storm Event
2026-04-01DP-2Nitrate3.5mg/LQualifying Storm Event
2026-04-01DP-2Nitrate/Nitrite (Nitrite + Nitrate as N)3.5mg/LQualifying Storm Event
2026-04-01DP-2Nitrogen, NitriteND (non-detect / est.)mg/LQualifying Storm Event
2026-04-01DP-2Oil and GreaseND (non-detect / est.)mg/LQualifying Storm Event
2026-04-01DP-2pH7.5SUQualifying Storm Event
2026-04-01DP-2Phosphorus.15mg/LQualifying Storm Event
2026-04-01DP-2Total Suspended Solids (TSS)7.5mg/LQualifying Storm Event
2026-04-01DP-2Zinc.15mg/LQualifying Storm Event
2026-04-01DP-3Chemical oxygen demand (COD)30mg/LQualifying Storm Event
2026-04-01DP-3Iron.56mg/LQualifying Storm Event
2026-04-01DP-3LeadND (non-detect / est.)mg/LQualifying Storm Event

Monitoring rows are official self-reported SMARTS submissions, joined to this facility by WDID. California Stormwater Intelligence does not restate, correct, average or evaluate reported values, and no benchmark comparison or violation determination is made.

YDOS-derived

Numeric Action Level comparison

Reported SMARTS analytical results compared against the Numeric Action Levels of the Industrial General Permit version in effect for each reporting year (July 1 – June 30).

Derived
Reporting years evaluated
11
Years with an NAL exceedance
8
Most recent evaluated year
RY 2025
Ruleset
igp_nal_ruleset_v1 / igp_nal_v1
ParameterNAL typeCalculated valueNALResultSamples usedMethod

Aluminum, Total

aluminum_total

Annual0.374 mg/L0.75 mg/LAt or below NALAnnual average of 13 eligible result(s) compared with the annual NAL.0.5× threshold13 eligiblearithmetic mean of all eligible effluent results in the July 1 - June 30 reporting year (censored results assigned zero only where MDL and ML were both reported)

Chemical Oxygen Demand (COD)

cod

Annual34.593 mg/L120 mg/LAt or below NALAnnual average of 27 eligible result(s) compared with the annual NAL.0.29× threshold27 eligiblearithmetic mean of all eligible effluent results in the July 1 - June 30 reporting year (censored results assigned zero only where MDL and ML were both reported)

Iron, Total

iron_total

Annual1.086 mg/L1 mg/LAbove NALAnnual average of 27 eligible result(s) compared with the annual NAL.1.09× threshold27 eligiblearithmetic mean of all eligible effluent results in the July 1 - June 30 reporting year (censored results assigned zero only where MDL and ML were both reported)

Lead, Total

lead_total

Annual0 mg/L0.262 mg/LAt or below NALAnnual average of 27 eligible result(s) compared with the annual NAL.0× threshold27 eligible27 non-detect as zeroarithmetic mean of all eligible effluent results in the July 1 - June 30 reporting year (censored results assigned zero only where MDL and ML were both reported)

Nitrite Plus Nitrate (as N)

nitrate_nitrite_n

Annual0.651 mg/L as N0.68 mg/L as NAt or below NALAnnual average of 20 eligible result(s) compared with the annual NAL.0.96× threshold20 eligible7 non-detect as zeroarithmetic mean of all eligible effluent results in the July 1 - June 30 reporting year (censored results assigned zero only where MDL and ML were both reported)

Oil and Grease

oil_grease

Instantaneous maximum0 samples above25 mg/LAt or below NALNo eligible result in this reporting year was outside the instantaneous maximum NAL.27 eligible27 non-detect as zerocount of eligible effluent results outside the instantaneous maximum NAL within the July 1 - June 30 reporting year

pH

ph

Instantaneous maximum0 samples above6 – 9 pH unitsWithin NAL rangeNo eligible result in this reporting year was outside the instantaneous maximum NAL.27 eligiblecount of eligible effluent results outside the instantaneous maximum NAL within the July 1 - June 30 reporting year

Phosphorus, Total (as P)

phosphorus_total

Annual0.529 mg/L as P2 mg/L as PAt or below NALAnnual average of 27 eligible result(s) compared with the annual NAL.0.26× threshold27 eligiblearithmetic mean of all eligible effluent results in the July 1 - June 30 reporting year (censored results assigned zero only where MDL and ML were both reported)

Total Suspended Solids (TSS)

tss

Instantaneous maximum0 samples above400 mg/LAt or below NALNo eligible result in this reporting year was outside the instantaneous maximum NAL.27 eligible3 non-detect as zerocount of eligible effluent results outside the instantaneous maximum NAL within the July 1 - June 30 reporting year

Zinc, Total

zinc_total

Annual0.043 mg/L0.26 mg/LAt or below NALAnnual average of 27 eligible result(s) compared with the annual NAL.0.17× threshold27 eligible4 non-detect as zeroarithmetic mean of all eligible effluent results in the July 1 - June 30 reporting year (censored results assigned zero only where MDL and ML were both reported)

YDOS-derived overlap

Pollutant overlap with impaired receiving waters

Parameters where this facility has an NAL exceedance in at least one reporting year and the geographically associated waterbody carries a 303(d) listing for the same pollutant.

Derived

AluminumMonitoringAbove NAL303(d) impairmentMad River HU, Mad River

3 reporting years above the annual NAL, most recently RY 2023 · 1 303(d) listing · association: derived nearby in watershed (high confidence)

Overlap is informational co-occurrence between a derived NAL comparison and an official 303(d) listing. It is not evidence that this facility caused or contributed to the impairment.

An NAL exceedance is a permit-defined condition that triggers Exceedance Response Actions under the Industrial General Permit. It is not a violation, an enforcement action, or a Water Board compliance determination. Annual values use the arithmetic average of eligible results with non-detects treated as zero; instantaneous maximum NALs (total suspended solids, oil and grease, pH) are exceeded when two or more eligible results in a reporting year fall outside the level. Rules transcribed from 2014-0057-DWQ as amended by 2015-0122-DWQ (effective 2015-07-01, superseded 2020-06-30); 2014-0057-DWQ as amended by 2018-0028-DWQ (effective 2020-07-01).

Documents

Documents on file

Attachment inventory recorded in the State Water Board SMARTS public attachment workflow for this permit.

Source inventory — SMARTS public attachments. Documents are operator-submitted.

Metadata indicators

Derived
Substantive documents on file
116
SWPPP versions on file
8
Most recent SWPPP attached
2026-04-01
Most recent substantive document
2026-07-13
Annual report years on file
2016, 2017, 2018, 2019, 2020, 2021, 2022, 2023, 2024, 2025, 2026
Apparent year gaps in annual reports
None apparent
ERA-related documents
13
Enforcement / inspection / laboratory documents
0 / 1 / 28

Document indicators are YDOS-derived counts and dates calculated from SMARTS attachment metadata. They describe what is on file, not whether a facility complied with any requirement.

116 substantive of 168 indexed attachments

SWPPP

12 documents

SWPPP Amendment #9

Source file type SWPPP · 2026-04-01 · 332 KB

SWPPP Amendment #9

Source file type SWPPP · 2026-03-25 · 332 KB

SWPPP amendment 7

Source file type SWPPP · 2022-06-10 · 1.1 MB

offsite map

Source file type Facility/Site Map · 2022-03-16 · 1.2 MB

SWPPP amendment

Source file type SWPPP · 2022-03-16 · 39.7 MB

SWPPP amendment

Source file type SWPPP · 2021-07-02 · 39.7 MB

Site Maps

Source file type Facility/Site Map · 2021-07-01 · 3.5 MB

Royal Gold IGP SWPPP

Source file type SWPPP · part 1/1 · 2017-10-17 · 35.7 MB

Royal Gold SWPPP 12-30-2016

Source file type SWPPP · part 1/1 · 2016-12-30 · 36.9 MB

2012 Site Map

Source file type Facility/Site Map · part 1/1 · 2016-10-05 · 887 KB

Royal Gold SWPPP

Source file type SWPPP · part 1/1 · 2015-08-12 · 9.2 MB

Royal Gold Site Map

Source file type Facility/Site Map · part 1/1 · 2015-08-12 · 4.3 MB

Annual report

41 documents

Submitted report pdf

Source file type Submitted Report PDF · 2026-07-13 · 1.0 MB

Submitted report pdf

Source file type Submitted Report PDF · 2026-05-05 · 414 KB

Submitted report pdf

Source file type Submitted Report PDF · 2026-04-01 · 413 KB

Submitted report pdf

Source file type Submitted Report PDF · 2025-12-03 · 415 KB

Submitted report pdf

Source file type Submitted Report PDF · 2025-11-17 · 413 KB

Submitted report pdf

Source file type Submitted Report PDF · 2025-07-14 · 1003 KB

Submitted report pdf

Source file type Submitted Report PDF · 2025-06-09 · 415 KB

Submitted report pdf

Source file type Submitted Report PDF · 2024-12-20 · 416 KB

Submitted report pdf

Source file type Submitted Report PDF · 2024-07-09 · 418 KB

Submitted report pdf

Source file type Submitted Report PDF · 2024-07-09 · 1003 KB

Submitted report pdf

Source file type Submitted Report PDF · 2024-01-12 · 417 KB

Submitted report pdf

Source file type Submitted Report PDF · 2024-01-12 · 417 KB

Submitted report pdf

Source file type Submitted Report PDF · 2023-07-31 · 1003 KB

Submitted report pdf

Source file type Submitted Report PDF · 2023-07-10 · 1003 KB

Submitted report pdf

Source file type Submitted Report PDF · 2023-06-08 · 419 KB

Submitted report pdf

Source file type Submitted Report PDF · 2023-01-12 · 420 KB

Submitted report pdf

Source file type Submitted Report PDF · 2022-06-09 · 419 KB

Submitted report pdf

Source file type Submitted Report PDF · 2022-06-09 · 1003 KB

Submitted report pdf

Source file type Submitted Report PDF · 2022-03-01 · 418 KB

Submitted report pdf

Source file type Submitted Report PDF · 2021-07-02 · 1003 KB

Submitted report pdf

Source file type Submitted Report PDF · 2021-06-17 · 413 KB

Submitted report pdf

Source file type Submitted Report PDF · 2021-02-11 · 108 KB

Submitted report pdf

Source file type Submitted Report PDF · 2020-06-24 · 999 KB

Submitted report pdf

Source file type Submitted Report PDF · 2020-06-17 · 111 KB

Submitted report pdf

Source file type Submitted Report PDF · 2020-02-13 · 112 KB

Submitted report pdf

Source file type Submitted Report PDF · 2020-01-06 · 113 KB

Submitted report pdf

Source file type Submitted Report PDF · 2019-04-11 · 112 KB

Submitted report pdf

Source file type Submitted Report PDF · 2019-04-11 · 109 KB

Submitted report pdf

Source file type Submitted Report PDF · 2018-12-31 · 405 KB

Submitted report pdf

Source file type Submitted Report PDF · 2018-07-16 · 11 KB

Submitted report pdf

Source file type Submitted Report PDF · 2018-07-11 · 411 KB

Submitted report pdf

Source file type Submitted Report PDF · 2018-02-13 · 411 KB

Submitted report pdf

Source file type Submitted Report PDF · 2018-01-12 · 411 KB

Submitted report pdf

Source file type Submitted Report PDF · 2018-01-09 · 405 KB

Submitted report pdf

Source file type Submitted Report PDF · 2017-12-29 · 405 KB

Submitted report pdf

Source file type Submitted Report PDF · 2017-07-12 · 911 KB

Submitted report pdf

Source file type Submitted Report PDF · 2017-05-25 · 412 KB

Submitted report pdf

Source file type Submitted Report PDF · 2017-02-08 · 410 KB

Submitted report pdf

Source file type Submitted Report PDF · 2017-01-18 · 405 KB

Submitted report pdf

Source file type Submitted Report PDF · 2016-07-13 · 408 KB

Submitted report pdf

Source file type Submitted Report PDF · 2016-07-13 · 911 KB

ERA report

13 documents

ERA Level 2 Technical Report, Aluminum (Total)

Source file type Level 2 Technical Report · 2025-12-30 · 3.2 MB

20241230-RG-Level2APAlandFe

Source file type Level 2 ERA Action Plan · 2024-12-31 · 638 KB

Level 2 Technical Report update

Source file type Level 2 Technical Report · 2023-12-29 · 453 KB

ERA Level 2Technical Report – Iron

Source file type Level 2 Technical Report · 2022-12-27 · 606 KB

Exceedance Response Action Level 2 Action Plan–Iron

Source file type Level 2 ERA Action Plan · 2022-01-03 · 711 KB

ERA Level 1 Al

Source file type Level 1 Technical Report · 2021-12-31 · 420 KB

Exceedance Response Action Level 2 Technical Report-Iron, Total Suspended Solids, and N+N

Source file type Level 2 ERA Action Plan · part 1/1 · 2019-07-01 · 3.9 MB

Level 2 Extension Request Letter

Source file type Level 2 Technical Report · part 1/1 · 2018-12-21 · 64 KB

Revised Exceedance Response Level 2 Action Plan

Source file type Level 2 ERA Action Plan · part 1/1 · 2018-12-21 · 4.1 MB

20180105 RG Level1ERA RptAl

Source file type Level 1 Technical Report · part 1/1 · 2018-01-05 · 2.3 MB

20171228 Royal Gold Level 2 ERA

Source file type Level 2 ERA Action Plan · part 1/1 · 2017-12-28 · 9.7 MB

Level 1 ERA Report

Source file type Level 1 Technical Report · part 1/1 · 2017-01-10 · 2.0 MB

Level 1 ERA Report

Source file type Level 1 Technical Report · part 1/1 · 2016-12-30 · 2.0 MB

Inspection

1 document

093021 Final Inspection Report

Source file type Final Inspection Report · 2021-10-21 · 5.4 MB

Laboratory / ad hoc

28 documents

Laboratory report

Source file type Laboratory Results · 2026-04-17 · 310 KB

Laboratory report

Source file type Laboratory Results · 2026-03-30 · 795 KB

Laboratory Report

Source file type Laboratory Results · 2025-12-02 · 806 KB

Laboratory Report

Source file type Laboratory Results · 2025-11-04 · 781 KB

Lab Results

Source file type Laboratory Results · 2025-06-06 · 1.1 MB

Lab Results

Source file type Laboratory Results · 2024-12-19 · 754 KB

2403365

Source file type Laboratory Results · part 1/1 · 2024-04-11 · 505 KB

2311044

Source file type Laboratory Results · part 1/1 · 2024-01-08 · 459 KB

Apr 17, 2023 lab rpt

Source file type Laboratory Results · 2023-05-17 · 434 KB

Dec 1, 2022 lab rpt

Source file type Laboratory Results · 2023-01-08 · 460 KB

Apr 11, 2022 lab rpt

Source file type Laboratory Results · 2022-04-27 · 456 KB

Dec 21, 2021 lab rpt

Source file type Laboratory Results · 2022-01-22 · 473 KB

Apr 26, 2021 lab rpt

Source file type Laboratory Results · 2021-06-04 · 401 KB

Dec 22, 2020 lab report

Source file type Laboratory Results · 2021-01-19 · 367 KB

Jan 24, 2020 lab report

Source file type Laboratory Results · 2020-02-28 · 450 KB

Dec 19, 2019 lab rpt

Source file type Laboratory Results · 2020-01-28 · 300 KB

Nov 19, 2019 lab report

Source file type Laboratory Results · 2019-12-05 · 346 KB

Mar 20, 2019

Source file type Laboratory Results · part 1/1 · 2019-04-05 · 377 KB

Feb 4, 2019 lab rpt

Source file type Laboratory Results · part 1/1 · 2019-03-05 · 405 KB

Dec 24, 2018 lab rpt

Source file type Laboratory Results · part 1/1 · 2019-01-21 · 353 KB

Dec 10, 2018 lab rpt

Source file type Laboratory Results · part 1/1 · 2019-01-07 · 368 KB

May 25, 2018 lab rpt

Source file type Laboratory Results · part 1/1 · 2018-07-11 · 338 KB

Jan 16, 2018 lab rpt

Source file type Laboratory Results · part 1/1 · 2018-02-06 · 339 KB

Nov 28, 2017 lab report

Source file type Laboratory Results · part 1/1 · 2018-01-12 · 342 KB

4/7/17 Stormwater Lab Results

Source file type Laboratory Results · part 1/1 · 2017-05-25 · 306 KB

2016 2nd half Stormwater Test

Source file type Laboratory Results · part 1/1 · 2017-02-08 · 348 KB

June Stormwater discharge test results

Source file type Laboratory Results · part 1/1 · 2016-07-12 · 329 KB

Stormwater Test Results

Source file type Laboratory Results · part 1/1 · 2015-12-22 · 3.1 MB

Other substantive

21 documents

20240315-RG-SWPPP-Amend8

Source file type Supporting Documentation · part 1/1 · 2024-03-19 · 3.0 MB

SWPPP Amend 6

Source file type Supporting Documentation · 2021-07-31 · 1.8 MB

Level 2 Extension Request Letter

Source file type Cover/Explanation Letter · part 1/1 · 2018-12-21 · 64 KB

4/7/17 Visual Observation Log

Source file type Supporting Documentation · part 1/1 · 2017-05-25 · 2.7 MB

Level1ERA - Certification Page

Source file type Supporting Documentation · part 1/1 · 2016-12-30 · 282 KB

Pollutant Source Amendment

Source file type Other · part 1/1 · 2016-10-19 · 156 KB

October 16, 2012 RWB Inspection Memo

Source file type Memo · part 1/1 · 2016-10-05 · 663 KB

Royal GOld

Source file type Photograph · part 1/1 · 2016-09-27 · 2.5 MB

Royal GOld

Source file type Photograph · part 1/1 · 2016-09-27 · 3.1 MB

Royal Gold

Source file type Photograph · part 1/1 · 2016-09-27 · 3.4 MB

Royal Gold

Source file type Photograph · part 1/1 · 2016-09-27 · 2.4 MB

Royal Gold

Source file type Photograph · part 1/1 · 2016-09-27 · 2.2 MB

Royal Gold

Source file type Photograph · part 1/1 · 2016-09-27 · 2.6 MB

Royal Gold

Source file type Photograph · part 1/1 · 2016-09-27 · 2.0 MB

Royal Gold

Source file type Photograph · part 1/1 · 2016-09-27 · 1.7 MB

Royal Gold

Source file type Photograph · part 1/1 · 2016-09-27 · 2.8 MB

Royal Gold

Source file type Photograph · part 1/1 · 2016-09-27 · 1.7 MB

Royal Gold

Source file type Photograph · part 1/1 · 2016-09-27 · 3.2 MB

Royal Gold

Source file type Photograph · part 1/1 · 2016-09-27 · 3.2 MB

Royal Gold

Source file type Photograph · part 1/1 · 2016-09-27 · 3.1 MB

Royal Gold

Source file type Photograph · part 1/1 · 2016-09-27 · 2.2 MB

Enforcement

Enforcement records

Enforcement actions as recorded by the State Water Board for this permit, in the source system's own terminology.

Source record — SMARTS enforcement data

Structured enforcement records are not yet connected for this site. The absence of a record is not a finding about this facility.

Reporting

Reporting and ERA records

Annual report and Exceedance Response Action information as stated by the source system, distinguished from what is inferred from document metadata.

Source record — SMARTS reporting data

Annual report documents on file

Derived
Reporting years identified
2016, 2017, 2018, 2019, 2020, 2021, 2022, 2023, 2024, 2025, 2026
Apparent year gaps
None apparent

Years are YDOS-derived from attachment metadata. A gap means no annual-report document was identified for that year in the attachment index — it is not a finding that a report was not filed.

Recent activity

Recent source changes

New or changed source records this platform detected for this permit, newest first.

Derived

No source change has been detected for this permit yet. Change detection begins from the date each dataset was first indexed.

Provenance

Source & provenance

Source agency
California State Water Resources Control Board
Source dataset
Industrial General Permit — permitted facilities (statewide GIS layer)
WDID
1 12I025790
Source feature ID
9195
Application type
Notice of Intent
Regional board derivation
WDID region prefix
Geometry status
valid
Last successful facility import
Sep 16, 2026, 10:48 PM UTC

Official IGP permitted facilities feature layer