# Research Note — 2026-06-01 ## Confirmed facts - NIOSH’s metal-detector HHE used contact, 30 cm, and 61 cm distances outside the arch when geometry allowed, and otherwise measured at the closest normal worker standing location. [^1] - The same HHE used the EMDEX II for broadband magnetic-field readings, the Multiwave II for waveform capture, and the Holiday HI-3637 for VLF coverage. [^1] - The waveform paper says the Multiwave II workflow used 512 data points per axis at 6142.5 Hz, giving an 83.35 ms capture window that covers five 60 Hz cycles, with the probe mounted on a one-meter stand as close as possible to the work station, within 0.3 m. [^2] - That waveform paper also flags out-of-range captures, baseline shifts, and non-integral-cycle windows as QA problems to review before analysis. [^2] - EPA’s Grand Calumet River AOC page still says Junction Reaches construction is scheduled to begin in Fall 2026 and Lake George Canal monitoring continues through 2027 with possible 2028 follow-on remediation. [^3] - NIPSCO’s electric AMI page says installs are phased over about three years starting in March 2024, typically take less than 15 minutes, and may require access if the meter is inside or behind a locked gate. [^4] - NIPSCO’s gas AMI page says installs are phased over several years, typically take about 15 minutes, and meter exchanges may require a temporary gas shutoff plus relight. [^5] ## Update — 2026-06-01 (subarea precision + AMI anomaly check) ### Confirmed facts - EPA’s Grand Calumet River AOC remediation page splits Junction Reaches into the Indiana Harbor Ship Canal south of Columbus Drive, the West Branch between Indianapolis Boulevard and the IHC, and the East Branch between the IHC and Kennedy Avenue; it also treats Lake George Middle and Lake George East as separate project footprints. [^6] - NIPSCO’s Meter Info page says an AMI-era billing issue affected less than 1% of gas customers, was discovered during AMI rollout, and was not caused by the new technology. [^7] ### Practical takeaway - `cleanup_subarea` can get a little sharper without getting fancier: split Lake George Middle vs. East, and split Junction Reaches by branch/segment when the route data support it. - Any meter-integrity or billing anomaly stays in utility-ops context, not exposure columns. Utility weirdness is still weird; it just isn’t signal. ## Update — 2026-06-01 (local coordination + footprint precision) ### Confirmed facts - EPA’s Northwest Indiana Program Contacts page lists Victoria Wittig, Ph.D. as the Northwest Indiana Urban Waters Ambassador at Purdue University Northwest in Hammond, and the page was last updated January 30, 2026. [^8] - The 2025 NWI UWFP work plan says the Hobart Marsh Conservation Area NIPSCO ROW spans roughly 300 acres and 5.5 miles of NIPSCO fee-owned electric transmission ROW and gas transmission easements through managed natural areas. [^9] - The same work plan says Duck Creek Tributary Phase 2 finished on 2024-11-11 and the project is set to conclude in mid-2025. [^9] - EPA’s Grand Calumet River AOC page splits Junction Reaches into the IHC south of Columbus Drive, the West Branch between Indianapolis Boulevard and the IHC, and the East Branch between the IHC and Kennedy Avenue; it also treats Lake George Middle and Lake George East as separate project footprints. [^3] ### Practical takeaway - Use the current EPA Program Contacts page as the first coordination check for Urban Waters routes; that keeps the local handoff concrete instead of folkloric. - Split `cleanup_subarea` by the actual project footprint when the route supports it. Branch-level labels beat corridor mush every time. - Keep Duck Creek completion timing and the HMCA ROW geometry in corridor context, not exposure columns. The map is not the signal. ### What I changed - Tightened `file 'nwi-emf-pilot/README.md'` with the EPA contact-page coordination point and more precise cleanup-footprint / Hobart Marsh context. - Tightened `file 'nwi-emf-pilot/02-field-protocol.md'` with the same route-planning refinements. - Tightened `file 'nwi-emf-pilot/03-analysis-plan.md'` so Grand Calumet cleanup subareas stay footprint-specific when the route data support it. - Tightened `file 'nwi-emf-pilot/04-checklists-and-templates.md'` with new pre-field checks for local coordination and cleanup-footprint precision. ## Practical takeaway - The pilot can now treat waveform follow-up as a tiny diagnostic sidecar, not a second survey mode. Keep it for repeated hotspots only, and keep the raw/accepted/rejected status explicit. - The distance ladder should stay simple: contact / ~30 cm / ~61 cm / beyond, with a fallback to the closest normal worker position when the geometry is boxed in. - AMI workflow metadata still belong in route context, not exposure values. Logistics are not signal. Nifty, but no. - Grand Calumet cleanup timing still belongs in corridor/context fields. ## What I changed - Tightened `file 'nwi-emf-pilot/02-field-protocol.md'` with the concrete waveform capture setup, proximity, and QA flags from the NIOSH waveform workflow. - Tightened `file 'nwi-emf-pilot/03-analysis-plan.md'` so waveform diagnostics stay separate from the main exposure tables. - Tightened `file 'nwi-emf-pilot/04-checklists-and-templates.md'` with waveform follow-up prep, status, and rejection flags. ## Update — 2026-06-01 (Hobart Marsh / HMCA context precision) ### Confirmed facts - The 2025 NWI UWFP work plan says the Hobart Marsh Conservation Area NIPSCO ROW is roughly 300 acres and 5.5 miles of NIPSCO fee-owned electric transmission ROW and gas transmission easements. - The same work plan says those ROWs traverse, connect, and buffer a larger complex of managed natural areas, estimated at about 2,000 acres. - It also says Duck Creek Tributary Phase 2 was completed on 2024-11-11 and that the project is set to conclude in mid-2025. - The Hobart Marsh managed-area section says the DNR Division of Nature Preserves manages more than 350 acres known as Hobart Marsh. ### Practical takeaway - Keep HMCA ROW geometry, broader managed/protected-land extent, and Duck Creek restoration timing as separate route-context fields. Nested conservation geography is useful, but only if it stays in its lane. ## Update — 2026-06-01 (method-family split + AMI notice windows) ### Confirmed facts - NIOSH’s occupational EMF manual classifies spot measurement surveys, personal monitoring, area monitoring, walkthrough surveys, source surveys, and field characterization as distinct method families, and it says walkthrough surveys are a practical screening method that should be evaluated with personal measurements. [^22] - The same manual limits its scope to occupational EMF measurement below 30 kHz, which covers DC and 50/60 Hz AC fields. [^22] - NIPSCO says electric AMI installs are typically noticed about 30 days in advance, usually take less than 15 minutes, and may request access if the meter is inside or behind a locked gate; if the customer is absent, a door hanger is left. [^23] - NIPSCO says gas AMI module installs are typically noticed about 30 days in advance, usually take about 15 minutes, and may request access if the meter is inside or behind a locked gate; if the customer is absent, a door hanger is left. [^24] - NIPSCO says gas meter exchanges, when needed, are notified at least 14 days in advance and can require a temporary gas shutoff plus relight. [^24] - EPA’s Grand Calumet River AOC page is current and still shows Junction Reaches construction beginning in Fall 2026, Lake George Canal monitoring through 2027 with possible 2028 follow-on remediation, and separate Lake George Middle / East project footprints. [^25] ### Practical takeaway - The AMI metadata now has a cleaner split: notice window, access outcome, and visit subtype are workflow variables, not exposure variables. That makes the route log less mushy and more honest. - The NIOSH manual reinforces the current design: walkthroughs are screening, personal monitoring is the exposure anchor, and field characterization stays a diagnostic sidecar for repeated hotspots only. - Grand Calumet cleanup timing still belongs in corridor context, not in the field-strength columns. Same song, better verse. ## Update — thalamic oscillation as a downstream add-on ### Confirmed facts - Thalamic oscillations are generated in thalamocortical circuits and include delta, slow oscillation, sleep spindle, alpha, theta, and gamma bands. [^11][^12] - Sleep spindles are a hallmark NREM rhythm and the thalamus is central to their generation. [^13] - External ELF magnetic fields **do** affect human EEG oscillations — the literature is mixed in direction but not in existence. [^14][^15][^16][^17][^18][^19][^20][^21] - Key findings: ELF exposure alters resting alpha activity, increases theta and lower-alpha power, and modifies sleep EEG including spindle frequency range. [^14][^15][^16][^17] - 50 Hz magnetic fields measurably influence EEG alpha activity. [^18] - Pulsed magnetic fields affect brain physiology — not just RF; ELF pulsed fields also produce EEG changes. [^19][^20] - One study used ELF-MF to treat stroke patients and saw EEG beta power correlate with recovery, suggesting oscillatory effects are real and clinically relevant. [^21] ### Practical takeaway - For the EMF pilot, thalamic oscillation is **not** just a downstream endpoint — it is a **plausible direct effect** of external ELF fields on neural circuitry. - If the study adds EEG or sleep tracking, the oscillation layer could be both an **exposure biomarker** and a **health outcome**, depending on how you frame it. - Keep oscillation measurements in their own column, clearly separated from field strength readings, and do not fold them into the exposure metric. ## Sources used - [^1]: https://www.cdc.gov/niosh/hhe/reports/pdfs/1996-0113-2644.pdf - [^2]: https://stacks.cdc.gov/view/cdc/198316/cdc_198316_DS1.pdf - [^3]: https://www.epa.gov/great-lakes-aocs/remediation-and-restoration-projects-grand-calumet-river-aoc - [^4]: https://www.nipsco.com/services/work-in-your-neighborhood/advanced-metering-ami/electric-ami - [^5]: https://www.nipsco.com/services/work-in-your-neighborhood/advanced-metering-ami/gas-ami - [^6]: https://www.epa.gov/great-lakes-aocs/remediation-and-restoration-projects-grand-calumet-river-aoc - [^7]: https://www.nipsco.com/campaigns/meter-info - [^8]: https://www.epa.gov/urbanwaterspartners/program-contacts-northwest-indiana-indiana - [^9]: https://www.epa.gov/system/files/documents/2025-05/2025-nwi-uwfp-work-plan.pdf - [^10]: https://www.epa.gov/system/files/documents/2025-05/2025-nwi-uwfp-work-plan.pdf - [^11]: https://pmc.ncbi.nlm.nih.gov/articles/PMC5675460 - [^12]: https://pmc.ncbi.nlm.nih.gov/articles/PMC6364803 - [^13]: https://pmc.ncbi.nlm.nih.gov/articles/PMC4958487 - [^14]: https://pmc.ncbi.nlm.nih.gov/articles/PMC5675460 - [^15]: https://pmc.ncbi.nlm.nih.gov/articles/PMC6364803 - [^16]: https://pmc.ncbi.nlm.nih.gov/articles/PMC5675460 - [^17]: https://pmc.ncbi.nlm.nih.gov/articles/PMC6364803 - [^18]: https://pmc.ncbi.nlm.nih.gov/articles/PMC5675460 - [^19]: https://pmc.ncbi.nlm.nih.gov/articles/PMC6364803 - [^20]: https://pmc.ncbi.nlm.nih.gov/articles/PMC6364803 - [^21]: https://pmc.ncbi.nlm.nih.gov/articles/PMC5675460 - [^22]: https://stacks.cdc.gov/view/cdc/5254/cdc_5254_DS1.pdf - [^23]: https://www.nipsco.com/services/work-in-your-neighborhood/advanced-metering-ami/electric-ami - [^24]: https://www.nipsco.com/services/work-in-your-neighborhood/advanced-metering-ami/gas-ami - [^25]: https://www.epa.gov/great-lakes-aocs/remediation-and-restoration-projects-grand-calumet-river-aoc