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Errors Register — BMP Crosswalk

Generated: 2026-03-12 Total errors: 11

Errors are claims in current OPAL content (BMP library pages, audit report, era_matrix.json) that conflict with each other or have not been verified against the authoritative OCR source PDFs.

Category Count
Unresolved conflicts (need PDF verification) 0
Omissions (content needs to be added) 3
Confirmed errors (correction required) 3

E-01: Mounding trigger threshold '> 2.99 in/hr' stated for 2023 rules

Status: RESOLVED — UNSUBSTANTIATED

Locations in current content: - Outs/1_Regulatory_Audit_Report.md §2.3

Resolution: The value '2.99' does NOT appear as an infiltration rate in any authoritative source. Full-text search of NJAC 7:8 found zero occurrences of '2.99'. The only '2.99' in the BMP Manual is in BMP 9.8 (Small-Scale Infiltration Basins) where it describes a depth measurement: 'sand layer at 2.99 ft below ground level' — NOT a rate trigger. NJAC 7:8-5.3(h) requires 'assess the hydraulic impact on the groundwater table' but specifies no numerical threshold. The era_matrix.json statement of 'no explicit depth threshold codified' is CORRECT.

E-02: Flood control design storm: '10-year' vs '100-year' conflict

Status: RESOLVED — BOTH sources partially correct

Locations in current content: - Outs/1_Regulatory_Audit_Report.md §2.4 — states 2-year and 10-year - Green-Guides/bmp-library/index.md OUTS_SYNC Non-GI section — states 2-year and 100-year

Resolution: NJAC 7:8-5.6(b)3 Page 42 specifies ALL THREE storm events: 'post-construction peak runoff rates for the current and projected two-, 10-, and 100-year storm events shall not exceed [50%, 75%, 80% respectively] of the pre-construction peak runoff rates'. The audit report's '2-year and 10-year' is incomplete (missing 100-year). The library index's '2-year and 100-year' is incomplete (missing 10-year). The correct standard covers 2-year, 10-year, AND 100-year storms.

Source page: NJAC 7:8 Page 42, Section 5.6(b)3

Source quote: post-construction peak runoff rates for the current and projected two-, 10-, and 100-year storm events shall not exceed 50, 75, and 80 percent, respectively, of the pre-construction peak runoff rates

E-03: Bioretention 2026 small-scale drainage area: '≤ 1 acre' vs '2.5 acre max' conflict

Status: RESOLVED — Library page INCORRECT

Locations in current content: - Green-Guides/bmp-library/ch9-small-scale-gi/bioretention.md — states ≤ 1 acre impervious (2026) - Toolbox/Tool_GWR_Rev1/Prep/era_matrix.json — states 2.5 acre max for small-scale GI (2026)

Resolution: Both 2023 BMP 9.7 Page 3 and 2026 BMP 9.7 Page 3 state: 'maximum contributory inflow drainage area is 2.5 acres'. NJAC 7:8-5.3(b) Table 5-1 confirms: 'Small-scale Bioretention Systems — Maximum Contributory Drainage Area: 2.5 acres'. The library page claim of '≤ 1 acre impervious' is INCORRECT or uses an unsubstantiated metric. Correct value is 2.5 acres total drainage area. NO change between eras.

Source page: BMP 9.7 Page 3 (both eras); NJAC 7:8-5.3(b) Table 5-1

Source quote: maximum contributory inflow drainage area is 2.5 acres

E-04: Dry well Ksat threshold 2026: 0.52 in/hr vs 0.5 in/hr from 2023

Status: RESOLVED — Library page INCORRECT

Locations in current content: - Green-Guides/bmp-library/ch9-small-scale-gi/dry-well.md Design Criteria

Resolution: Both 2023 BMP 9.2 Page 1 and 2026 BMP 9.2 Page 1 state: 'Minimum Design Permeability Rate of the Subsoil: 0.5 inches/hour'. Permeability Rate Factor of Safety: 2. Maximum Design Permeability Rate: 10 inches/hour. The '0.52 in/hr' claim is WRONG — correct value is 0.5 in/hr. NO change between eras.

Source page: BMP 9.2 Page 1 (both eras)

Source quote: Minimum Design Permeability Rate of the Subsoil: 0.5 inches/hour

E-05: 50% TSS removal threshold for existing modified impervious surfaces

Status: RESOLVED — Audit report MISLEADING

Locations in current content: - Outs/1_Regulatory_Audit_Report.md §2.2

Resolution: NJAC 7:8-5.5(b)2 Page 39: The general standard is 'Eighty percent TSS removal'. The 50% TSS applies ONLY to a 'public transportation entity that demonstrates that achieving 80 percent TSS removal...would require acquisition of developed or otherwise encumbered land outside of the entity's existing right-of-way.' This is a narrow exception for public roadway projects, NOT a general standard for existing impervious surfaces. The audit report's phrasing '50% TSS removal for existing modified impervious' is misleading.

Source page: NJAC 7:8 Page 39, Section 5.5(b)2

Source quote: Eighty percent TSS removal... a public transportation entity... minimum water quality treatment of 50 percent TSS removal for all new and reconstructed motor vehicle surface

E-06: Infiltration test method restriction: 'ASTM D5126 only' vs 'double-ring infiltrometer'

Status: RESOLVED — Audit report ASTM number INCORRECT

Locations in current content: - Outs/1_Regulatory_Audit_Report.md §2.5 — states 'restricted to in-situ falling head permeameter or ASTM D5126' - Green-Guides/bmp-library/ch9-small-scale-gi/dry-well.md — states 'double-ring infiltrometer or permeameter'

Resolution: BMP 12 Section 3a Page 27 (identical in both eras): Primary accepted test methods = percolation test, tube permeameter test, single ring infiltration test, basin flooding test (for fractured bedrock). Additional accepted methods = 'ASTM D3385 — Standard Test Method for Infiltration Rate of Soils in Field Using Double-Ring Infiltrometer' and 'USBR 7300-89 — Well Permeameter Method, or other soil hydraulic conductivity tests that utilize in-situ conditions and are accompanied by a recognized published source reference.' Post-construction (Page 29): 'Only the single ring infiltration test, the modified basin flooding test and the double ring infiltration test or a similar test that does not require a test hole in the soil layer are allowed.' The ASTM standard is D3385, NOT D5126. ASTM D5126 is a monitoring well standard.

Source page: BMP 12 Pages 27 and 29 (both eras)

Source quote: ASTM D3385 – Standard Test Method for Infiltration Rate of Soils in Field Using Double-Ring Infiltrometer

E-07: County Climate Adjustment Factor (Table 5-6) entirely absent from Regulatory Audit Report

Status: RESOLVED — OMISSION CONFIRMED

Locations in current content: - Outs/1_Regulatory_Audit_Report.md — not mentioned anywhere

Resolution: NJAC 7:8 Pages 45-46: Table 5-5 (Current Precipitation Change Factors) and Table 5-6 (Future Precipitation Change Factors) are fully present with all 21 NJ counties. Bergen County: 2-year=1.20, 10-year=1.23, 100-year=1.37. This is a significant 2026 change that creates ~20% undersizing risk if ignored. The audit report must be amended to include this.

Source page: NJAC 7:8 Pages 45-46, Tables 5-5 and 5-6

Source quote: Table 5-6: Future Precipitation Change Factors... Bergen: 2-year=1.20, 10-year=1.23, 100-year=1.37

E-08: Wooded/Good cover presumption (N.J.A.C. 7:8-5.7) absent from Regulatory Audit Report and all BMP pages

Status: RESOLVED — OMISSION CONFIRMED

Locations in current content: - Outs/1_Regulatory_Audit_Report.md — not mentioned anywhere - All BMP pages — not stated

Resolution: NJAC 7:8-5.7(a) Page 44: 'good hydrologic condition (if the land use type is pasture, lawn, or park), with good cover (if the land use type is woods)'. BMP 5 Page 12: 'pre-construction condition, the presumed state is wooded land use in good hydrologic condition'. BMP 5 Page 73: CN for HSG B + wooded/good = 55. This affects all recharge and runoff calculations.

Source page: NJAC 7:8 Page 44 §5.7(a); BMP 5 Pages 12, 73

Source quote: pre-construction condition, the presumed state is wooded land use in good hydrologic condition

E-09: SHWT mound apex distinction absent from all BMP pages

Status: RESOLVED — CLAIM UNSUBSTANTIATED

Locations in current content: - All BMP pages — state '2 ft below bottom of media' without specifying mound apex vs. static SHWT for 2026

Resolution: Comprehensive comparison of BMP 13 (2023 vs 2026) shows the text is IDENTICAL on SHWT measurement. Both eras state: 'recalculate the height of the mound, measured upward from the SHWT, which is at elevation 0.00.' The word 'apex' does NOT appear in BMP 13 (either era) or NJAC 7:8. The only wording difference is 2026 uses 'bottom surface' where 2023 says 'bottom' — a cosmetic change, not a substantive rule change. The AGENTS.MD claim that '2026: SHWT reference = mound apex' is NOT supported by any authoritative PDF. Both eras use static SHWT as the reference datum.

Source page: BMP 13 Page 14 (both eras); NJAC 7:8 (no apex references found)

Source quote: recalculate the height of the mound, measured upward from the SHWT, which is at elevation 0.00

E-10: K_design = K_field / 2.0 safety factor not stated in any BMP page or audit report

Status: RESOLVED — OMISSION CONFIRMED, but NOT a 2026-only requirement

Locations in current content: - All BMP pages — none mention K_design calculation - Outs/1_Regulatory_Audit_Report.md — not mentioned

Resolution: BMP 6 Page 17: 'minimum design soil permeability rates will vary from 0.2 to 0.5 inches per hour and that a factor of safety of 2 must be applied when converting a tested permeability rate to a design rate.' BMP 13 Page 4 (both eras): 'a factor of safety of 2 must be applied to the slowest tested permeability rate to determine the design permeability rate.' BMP 12 Section 2a confirms this. K_design = K_field / 2.0 EXISTS IN BOTH 2023 AND 2026 ERAS — it is NOT a new 2026 rule. The omission from OPAL content applies to both eras.

Source page: BMP 6 Page 17; BMP 13 Page 4 (both eras); BMP 12 Section 2a

Source quote: a factor of safety of 2 must be applied when converting a tested permeability rate to a design rate

E-11: Reference to '2021 Green Infrastructure rulemaking' date unverified

Status: RESOLVED — DATE EXPLAINED

Locations in current content: - Outs/1_Regulatory_Audit_Report.md introduction

Resolution: BMP 9.7 (2023 era) footer reads 'New Jersey Stormwater Best Management Practices Manual March 2021'. The '2021' date is the BMP Manual publication date for certain chapters (Ch. 9.7 was published March 2021). It is NOT a separate '2021 GI rulemaking' event. Different BMP chapters have different publication dates: some say 'March 2020', others 'March 2021', others 'March 2024'. The 2026 era chapters all say 'January 2026'. The audit report intro referencing '2021 Green Infrastructure rulemaking' conflates the manual revision date with a rulemaking event.

Source page: BMP 9.7 (2023) footer; BMP 13 (2023) footer says 'March 2020'

Source quote: New Jersey Stormwater Best Management Practices Manual March 2021