Magnetic Field Monitoring FAQ’s
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Magnetic fields are invisible lines of force produced by anything that generates, transmits, or uses electricity. Magnetic Fields associated with buried alternating current (AC) power transmission (in the case of Vineyard Wind 1) are at an extremely low frequency (60-Hz) and are a very low energy form of non-ionizing electromagnetic radiation [1].
Magnetic fields are created by moving electric charges, such as the current in electrical wires or currents in electrical appliances we all have in our homes. Magnetic fields can exert force on moving charges, and they are the mechanism by which electric motors generate mechanical power output. For Vineyard Wind 1, because the cables are buried, the normal electric fields one would encounter from overhead electric transmission and distribution power lines are absent because burial of the cables completely shields and grounds the electric fields. There are no above ground electric fields for the cables at Barnstable roads and Covell Beach parking lot as the cables are buried.
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There are two power transmission cables that have been installed since 2022 deep under Covell’s Beach, which bring power ashore for the Vineyard Wind 1 project. Both cables surface about 8- 10 feet below the pavement in the back end of the Covell’s lot under four rectangular manhole covers that are visible/level with the pavement. Nothing is otherwise visible above ground at the Beach. The power cables then proceed north under Craigville Beach Road and under several other town roads to the project’s substation in Independence Park in Hyannis. This infrastructure is very similar to the National Grid cable under Kalmus Beach in Hyannis, which brings power to Nantucket and has been operating safely for years under a busy beach parking lot.
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World Health Organization, 2024: “Despite the feeling of some people that more research needs to be done, scientific knowledge in this area is now more extensive than for most chemicals.” “Despite extensive research, to date there is no evidence to conclude that exposure to low level electromagnetic fields is harmful to human health”[2].
National Cancer Institute, 2022: "No consistent evidence for an association between any source of non-ionizing EMF and cancer has been found”[3].
In 2024, the State of New York’s energy agency (NYSERDA) held an informative briefing on onshore magnetic fields and offshore wind. Led by experts they retained from informative resources on this topic. Recording Link. Link to Slides.
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The Healey-Driscoll administration has sent two letters to the Town of Barnstable on this matter, in response to communications sent to the Commonwealth by Town Manager Mark Ells. The first letter in June 2024 from the Massachusetts Assistant Secretary for Energy Mike Judge and DPH Commissioner Robbie Goldstein.
“The transmission lines under Covell's Beach and those proposed for Craigville and Dowses beaches produce low level electromagnetic fields. By comparison, the ordinary use of a vacuum, an electric shaver, or keeping the television on produces stronger electromagnetic fields than an electric cable.”
“The World Health Organization (WHO) concluded that “[magnetic field] exposures below the limits recommended in the International Commission on Non-Ionizing Radiation Protection (“ICNIRP”) international guidelines do not appear to have any known consequence on health. The ICNIRP recommended exposure limit is 2,000 mG, which is nearly 95 times greater than that highest modeled value for the Vineyard Wind cables at Covell's Beach.”
Assistant Secretary Judge sent a second letter to the Town in February 2026, after Town Manager Ells had shared with the Commonwealth a report from SGDB that was shared with the Town of Barnstable in November 2025, and had asked the Commonwealth for a response.
“In the 325 readings that SGDB states that it has taken on Covell’s Beach itself over the six month period, the highest EMF reading registered was 7.5 milligauss (“mG”), recorded at the landward edge of the beach on August 31, 2025. In the middle of the beach, the highest EMF reading registered was 2.9 mG on October 19, 2025. These values are notably lower than the modeled EMF values presented by Vineyard Wind in the facility’s EFSB proceeding.”
“Accordingly, the readings taken on the beach, where people are more likely to congregate for extended periods of time, are roughly at or below levels that an average person might be exposed to at any time throughout the course of a given day and therefore, EEA remains confident that the transmission lines pose no threat to public health or safety for beachgoers.”
“With respect to the readings taken in the parking lot on top of the splicing vault where the cables are converted to onshore transmission lines and along the duct bank housing the transmission lines, the EMF readings are predictably higher. In the case of the splicing vault, this represents the closest that any member of the public can get to the transmission lines themselves. The highest reading taken at that location was 231.1 mG, taken at ground level on December 21, 2025. Notably, the reading taken at the same spot on the same day just one meter above ground level was 72.9 mG, a 68.5% reduction from the reading taken at ground level. This is consistent with how EMF is known to work, as EMF levels rapidly dissipate as one moves even just a short distance away from its source.”
“Presumably, members of the public are unlikely to spend all day sitting on top of the splicing vault or the duct banks. As a result, they are unlikely to be exposed to these levels of EMF for longer than a very brief period of time as they pass by these areas. Regardless, even if someone were to spend an extended period of time in these specific locations, the EMF levels reported by SGDB are still approximately 10-100 times lower than the 2,000 mG exposure limit recommended by the International Commission on Non-Ionizing Radiation Protection. The World Health Organization has concluded that magnetic field exposures below these limits “do not appear to have any known consequence on health”.”
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The June 2024 side agreement between the Town of Barnstable and Park City Wind/New England Wind 1 addressed this issue in Section 4A:
“With regard to magnetic fields, PCW and the Town agree that, as of the date of this Agreement, the International Commission on Non-Ionizing Radiation Protection (“ICNIRP”) has identified a power-frequency magnetic field safety guideline of 2,000 milligauss. Accordingly, magnetic field readings less than 2,000 milligauss on Craigville Beach are assumed to be safe, without any implication that numbers above that guideline necessarily pose an unacceptable risk to human health or the environment, and subject to subsequent changes to the ICNIRP guideline or new, science-based information.”
Barnstable Town Councilor Barry Sheingold spoke on this matter in great detail at the 11/20/25 Town Council meeting. You can watch Councilor Sheingold’s very detailed comments at the appx 1:24:00 mark of this video.
“I think it’s important that the town not give this document, this report, more credibility than it deserves on its merits.”
“While styled as a comprehensive report, the memo does not even mention what is generally accepted as the relevant safety guideline of 2000mg for magnetic fields. Which is considerably higher than the test results indicated in the report.”
“I don’t think that this report raises any serious public health concerns. Nor given the shortcomings I have referenced, does it demonstrate excessive magnetic fields relative to the modeling presented to the siting board.”
Barnstable resident and former Health and Safety Officer for Vineyard Wind 1 – Joe O’Brien – spoke at the Barnstable Town Council meeting on 12/4/25. You can watch Joe’s comments at the appx. 49:30 mark of this video.
“Before I decided to work for Vineyard Wind years back, I looked into the infrastructure associated with this project to make sure I was comfortable with it. Especially given I’ve spent most of my adult life on the Barnstable Recreation Commission, supporting our beaches and community. Retiring in 2022 after 40 years on the Rec. Commission. What I found is that this infrastructure is safe and well planned.”
“From listening to Councilor Sheingold and doing my own research, it appears to me that there is no public health concern or threat from the Vineyard Wind project. And any people or groups stating otherwise are just trying to scare people, in my opinion.”
Barnstable seasonal resident, MIT Professor and expert on electromagnetic fields, John Kassakian, is a Professor of Electrical Engineering at the Massachusetts Institute of Technology and a solid source for information. More about John.
In 2024, John commented to the Cape Cod Times:
John Kassakian, Massachusetts Institute of Technology professor emeritus of electrical engineering, said cables identical to those used "have been in use for years in locations like those through which the cables pass in Barnstable." The magnetic fields associated with the currents are offset by physical and electrical characteristics of the cable and installation, he said. First, each cable is wrapped with a metal jacket, which reduces the magnetic field and contains the electric field. The fields created by the cables are also "temporally orthogonal," Kassakian explained, meaning the fields of each cable cancel each other at varying degrees depending on their proximity with one another "relative to the distance to the point of measurement." Since the separation of the cables is less than 50 feet, he said "there will be measurable magnetic field cancellation at the beach surface." “The intensity of the magnetic field decreases in proportion to the distance from the field source, the cable in this case," so with depth, the field strength is lessened. Magnetic and electric fields created by overhead lines with the same voltage and power levels of the offshore cables, measured at ground level "would be considerably higher" than those measured on the beach, he said. "While there’s been controversy about the effects of these fields on people, the consensus is that there isn’t any," said Kassakian. A Barnstable resident himself. he said he doesn't believe the cables under the beach would pose any hazard. "I have a pacemaker and would have no concern about lying on the beach over the cables," he said.
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The recognized entity for guidance on magnetic field exposure is the INTERNATIONAL COMMISSION ON NON-IONIZING RADIATION PROTECTION (ICNIRP). ICNIRP has established a health-based guideline for allowable public exposure to low frequency magnetic fields from AC power transmission sources at 2000 milli-Gauss (mG) for members of the general public. Most countries and U.S. authorities use this standard. Including the Commonwealth of Massachusetts, as referenced in the above 2024 and 2026 letters from the Commonwealth. It is also, as stated above, the standard the Town of Barnstable has recognized in its 2024 Side Agreement with Park City Wind, LLC.
A second higher standard is issued by the International Committee on Electromagnetic Safety (ICES), which provided a 2020 recommendation of a reference level of 9,040mg for public exposure to 60 Hz electromagnetic fields.
Notes:
See Exhibit 1 for a more detailed outline of allowable magnetic field exposure by industry/type.
See Exhibit 2 for a listing of magnetic field levels from various household appliances.
See Exhibit 3 for magnetic field readings from other natural and manmade sources. Note: Allowable magnetic field exposure for medical procedures is much much higher. MRI’s and other medical equipment come with magnetic field exposure to the human body in the millions of milli-Gauss, as you can see in Exhibit 3.
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No, not at all. Commentary during the 6/30 meeting with Board member Luczkow touched on this. The fact is that underground and above ground electric transmission cables are abundant across the U.S. in every community. As detailed above, Barnstable has hosted a National Grid buried transmission cable underneath Hyannis roads and Kalmus Beach for years.
Per the Cape Cod Times in 2024: John Kassakian, Massachusetts Institute of Technology professor emeritus of electrical engineering, said cables identical to those used "have been in use for years in locations like those through which the cables pass in Barnstable."
Offshore wind is new to the United States, but electrical transmission infrastructure under beaches and roads is not.