Proposed New Jersey Regulations Governing Magnetic Fields From Electric Power Transmission Lines

DISCLAIMER: This document is preliminary and conceptual in nature. It is a draft working document which is intended solely for the purpose of stimulating discussion. As such, any statement contained herein, including those regarding policies or rule provisions, is subject to change. The New Jersey Department of Environmental Protection and Energy shall not be bound by any statement contained in this document.

    for further information contact:
    Dr. Daniel Wartenberg, Chair
    Advisory Committee on Non-Ionizing Radiation
    (908) 445-0197
    (908) 445-0784 (fax)
    dew@eohsi.rutgers.edu (email)

In 1958, the Radiation Protection Act, N.J.S.A. 26:2D-l et seq. (hereinafter, the Act) was enacted. This Act provides authority to set standards for the possession, handling, transportation and use of sources of radiation within the State of New Jersey. The Act also created the New Jersey Commission on Radiation Protection (hereinafter called the Commission) and vested in that body the authority to promulgate rules and regulations as may be necessary to prohibit and prevent unnecessary radiation. Pursuant to the Act, the Department of Environmental Protection (hereinafter, the Department) administers the rules promulgated by the Commission and also has the authority to charge fees for the services it performs.

Much concern has arisen regarding the possible adverse human health effects associated with exposure to electric and magnetic fields from 60 Hertz (Hz) electric power transmission, subtransmission and/or distribution lines and other sources including appliances. The concern originates from a series of epidemiologic studies, some of which show that children with cancer (particularly leukemia, lymphoma and brain cancer) are more likely to live in residences with higher magnetic field exposures, as inferred from the configuration of the electrical distribution wires, measured magnetic fields and historically reconstructed magnetic fields. In addition, a series of occupational studies have shown that workers with high magnetic field exposures, as inferred from job classifications and magnetic field measurements, often have higher rates of cancer (particularly leukemia, male breast cancer and brain cancer).

However, there is no postulated mechanism of carcinogenesis due to exposure to magnetic fields (except for breast cancer) and there is little experimental evidence to support the epidemiologic findings. Possible explanations for the inconsistencies include alternative explanations for the increased rates of cancer (i.e., confounding) and use of inappropriate exposure measures. It is believed that it will be a number of years before this issue is resolved scientifically, and before a biologically relevant measure of exposure can be validated if an association between exposure and disease truly exists.

If the association is confirmed, and if we assume as with chemical carcinogenesis that more is worse, living in close proximity to electric power transmission, subtransmission and/or distribution lines could put residents of New Jersey at excess risk of cancer. Therefore, to carry out the charge of prohibiting and preventing unnecessary exposure of the population of New Jersey to radiation, the New Jersey Commission on Radiation Protection believes it is prudent to reduce potential exposure from fields produced by electric power transmission, subtransmission and distribution lines. The inconsistent results of both the laboratory studies and the epidemiological studies which have been conducted to date preclude their use as a basis for the development of scientifically defensible exposure limits. As a first step, the Commission believes it is prudent to reduce the magnetic fields from all new or modified electric power transmission lines to levels as low as reasonably achievable (hereafter, ALARA).

New and modified electric power transmission lines have been chosen for the first regulation for three reasons. First, either these lines do not yet exist or they are existing lines that have been proposed by the utility or non-utility line owner for modification. Therefore, changing the wire configuration, or the phasing or other line characteristics to lower the resultant magnetic field should, in most cases, cause only small changes and limited economic costs for the utilities or ratepayers. The Commission believes such limited cost increments are warranted given the potential hazard of magnetic field exposures. Similar restrictions for existing lines could cause major disruptions and force the utilities to incur great expense. The Commission believes that these changes to existing lines are not warranted at this time, given the scientific data.

Second, the magnetic fields associated with electric power transmission lines of 100 kilovolts or greater are readily predicted using mathematical equations given line load data and information of the wire configuration. Therefore, the impact of specific modifications can be determined in advance, to a reasonable degree of certainty, and evaluated by an enforcement body. Similar predictions for electric power sub-transmission and distribution lines are less precise and more subject to interactions with other sources of magnetic fields.

Third, for those residences with highest magnetic fields, generally the majority of the field comes from the electric power transmission line. Thus, assuming that the greater the magnetic field the greater the risk, regulating the electric power transmission lines will limit exposure for those exposed to the highest fields, i.e., those at greatest risk. The Commission acknowledges that this population may represent a relatively small proportion of all of those exposed, and thus may not represent a majority of the risk borne by the population of New Jersey, but nonetheless believes that those at greatest risk must be protected first. The Commission notes that there may be higher, short-term, controllable, residential exposures than those from electric power transmission lines, such as those due to appliances, but that such exposures are not addressed under these regulations at the current time.

For these reasons, and in order to establish and fund a program within the Department to study and address without unnecessary delay issues related to electric and magnetic fields, the Commission deems it appropriate at this time to regulate only new and modified electric power transmission lines that operate at voltages of 100 kV or greater. The Commission also mandates funds to establish a program within the Department whereby a database of information on but not limited to new or modified electric power transmission and subtransmission lines (26 kV and above) will be established to provide empirical data for consideration during the development of future regulations. This database shall include: (1) measured values for the electric and magnetic fields for all 26 kV and above electric power lines including multiple circuit configurations, with the operating parameters and configuration of the lines during measurement; (2) models that can be used to predict the fields for various systems and load conditions.

A section-by-section summary of proposed N.J.A.C. 7:28-44 follows:

N.J.A.C. 7:28-44.1 defines the purpose and scope of this subchapter.

N.J.A.C. 7:28-44.2 defines relevant terms.

N.J.A.C. 7:28-44.3 defines the procedures for new or modified electric power transmission lines.

N.J.A.C. 7:28-44.4 defines the procedures for new or modified electric power subtransmission lines.

N.J.A.C. 7:28-44.5 defines measurement methodology.

N.J.A.C. 7:28-44.6 defines computational methodology.

N.J.A.C. 7:28-44.7 defines the use of recreational areas within Rights-of-Way.

N.J.A.C. 7:28-44.8 defines the method of fee computation.

The public has become increasingly concerned about potential dangers from exposure to electric and magnetic fields from 60 Hz electric power transmission lines. Proposed N.J.A.C. 7:28-44 will require electric power transmission lines to have incorporated design features that will reduce the magnetic fields to levels as low as reasonably achievable. It will also require that a database be established including but not limited to new or modified 26 kV and above electric power transmission and subtransmission lines for consideration of population exposures and establishment and impact of additional regulations. This regulation is a first step toward assuring that public exposure to magnetic fields from new or modified electric power transmission lines is as low as reasonably achievable and that patterns of public exposure to corresponding fields from lower voltage lines is characterized. The latter will allow the Department to identify potential areas of interest and serve as a basis for the development of future regulations.

(the section on fees will be added in a later revision)

Proposed N.J.A.C. 7:28-44 establishes rules which insure that the magnetic fields generated by future electric power transmission lines within and at the edge of their ROW be as low as reasonably achievable. Furthermore, the rules forbid the construction of new recreational areas underneath existing or future electric power transmission lines, and where possible mandate the placing of warning signs at recreational areas that are now located under or immediately adjacent to electric power transmission lines.

There are less than one hundred non-utility generators who meet the requirements of small businesses as defined in New Jersey Regulatory Flexibility Act N.J.S.A. 52:14B-l et seq., in New Jersey. Of that number approximately two may be impacted by this regulation yearly. The major utilities which buy power from non-utility generators usually own the electric power transmission lines but the non-utility generators could incur an added expense associated with designing and building a line that would meet the provisions of this rule.

Full text of the proposed new rule follows:

7:28-44.1 Scope and Purpose

This rule establishes requirements for the regulation of magnetic fields generated by electric power transmission and subtransmission lines as defined herein.

7:28-44.2 Definitions

The following words and terms, when used in this subchapter, shall have the following meanings, unless the context clearly indicates otherwise.

• Alternating current means a periodic sinusoidal current, alternately varying between equal positive and negative peaks. The unit for measuring the strength of the alternating current is the ampere (A).
• ANSI is the American National Standards Institute, Inc.
• Anticipated average and maximum current flow means those averages and maximum circuit currents expected as determined from historical or special study data.
• Centerline means the real or imaginary line designating the center of the circuit(s) comprising the electric power transmission or subtransmission line. Commission means the New Jersey Commission on Radiation Protection.
• Department means the New Jersey Department of Environmental Protection.
• Electric field means the RMS (root mean squared) amplitude of the electric field produced by an electric power transmission line as measured at a height of one meter above ground level, expressed in kilovolts per meter (kV/m).
• Electric power line means transmission and other lower voltage lines.
• Electric power distribution line for the purposes of this subchapter, means a system of conductors used to transport electrical energy of an alternating current at voltages equal to or less than 26 kilovolts, at a frequency of 60 Hz, from a source or sources of supply to other principal parts of the system, including to consumers' service entrance equipment.
• Electric power subtransmission line for the purposes of this subchapter, means a system of conductors used to transport bulk electrical energy of an alternating current at voltages equal to or greater than 26 kilovolts, but less than 100 kilovolts, and at a frequency of 60 Hz, from a source or sources of supply to other principal parts of the system.
• Electric power transmission line for the purposes of this subchapter, means a system of conductors used to transport bulk electrical energy of an alternating current at voltages of 100 kilovolts or greater and at a frequency of 60 Hertz (Hz), from a source or sources of supply to other principal parts of the system.
• Electric power transmission or subtransmission line owner means the legal owner of an electric power transmission or subtransmission line.
• Exposure means an instance where a person is within the electric and magnetic field created by an electric power transmission, subtransmission or distribution line.
• Frequency means the number of complete cycles of sinusoidal variations per unit of time, expressed in Hertz (cycles per second). For electric power facilities in the United States, the commonly used frequency is 60 Hz.
• Hertz (Hz) is the SI unit for cycles per second.
• Highest operating voltage means the maximum voltage value set forth for a particular electric power transmission line in Table 1, ANSI C84.1, Voltage Ratings for Electric Power Systems and Equipment (60 Hz), latest revision, or ANSI C92.2, Preferred Voltage Ratings for Alternating-Current Electrical Systems and Equipment Operating at Voltages above 230 Kilovolts Nominal, latest revision.
• IEEE means the Institute of Electrical and Electronic Engineers, Inc.
• Kilovolt (kV) means one thousand volts. Kilovolt per meter means a unit of measurement of electric field strength generally measured at a point one meter above ground and expressed as kV/m.
• Magnetic field means the RMS (root mean squared) amplitude of the magnetic flux density produced by an electric power line as measured one meter above ground, expressed in gauss or tesla.
• Maximum current rating (MCR) means the maximum quantity of electric current, expressed in amperes that can be continuously carried by the conductors of an electrical circuit as determined by the electrical power transmission or subtransmission line owner.
• Modified means the alteration of a portion of an electric power transmission or subtransmission line, said portion having a minimum length of 0.5 mile, by reconductoring, reinsulating or rebuilding for any reason that may result in any change to the magnetic field arising from electric current flow on this line after the effective date of this rule.
• Phase means the separation in time between each voltage with its associated current and the conductor(s) that comprise a polyphase system. All peak voltages are equal in magnitude as are all peak currents but each voltage/current is displaced from the other by equal time intervals. For instance, a three (3) phase 60 Hz system would have its voltages/currents separated by 1/180 of a second.
• Recreational area means any area used for active, non- occupational activities such as but not limited to playgrounds, ball fields, tennis courts and school yards. This is not meant to apply to passive uses such as hiking or camping.
• RMS means root-mean-squared which is the square root of the mean of the squares of the instantaneous values for a sine wave. For a sine wave, it is numerically equal to 0.707 of the maximum value.
• Right-of-way (ROW) means a term used only for the purposes of determining the appropriate points for compliance with this rule, and not for the purpose of determining a legal interest in the property and may mean any of the following, as appropriate:
  • (a) Land where the electric power line owner has property interest, such as, but not limited to, an easement, prescriptive easement, or fee simple title, and which is used or designated for construction, operation, and maintenance of electric power transmission lines
  • (b) In areas where the electric power line owner has a property interest as described in (a) and where such interest is adjacent to a public road or adjacent to or within the boundary of a property or easement of a railroad, utility pipeline, communication line, or public utility linear facility, or conservation zone, or canal, the ROW will be assumed to extend to the furthermost edge of such property or easement.
  • (c) In areas where the electric power line owner does not have a property interest in the land where the electric power transmission line is located, or where the electric power transmission line is located in a public road, for the purpose of this rule, the ROW will be assumed to extend 65 feet from each outside conductor.
  • (d) For electric power line crossings of public roads and bodies of water, the ROW, for the purposes of this rule, shall be assumed to extend 65 feet from each outside conductor.
• Standard horizontal configuration means all circuit conductors or conductor bundles lie in a horizontal plane perpendicular to the centerline of the transmission line.
• Standard low reactance configuration means the phases of multiple circuits are not arranged in the same physical positions or electrical sequence, so as to produce the minimum circuit reactance.
• Standard superbundle configuration means the phases of multiple circuits are arranged in the same relative positions and electrical sequence, so as to produce the lowest voltage gradient at the surface of the conductors.
• Voltage means the effective RMS (root mean squared) potential difference between any two conductors or between a conductor and ground, expressed in the unit of the volt (V). Voltages are expressed in nominal values as set forth in Table 1, ANSI C84.1, Voltage Ratings for Electric Power Systems and Equipment (60 Hz), latest revision, unless otherwise indicated. The nominal voltage is the value assigned for the purpose of convenient designation. The operating voltage may vary above or below this value.

(a) Any owner seeking to construct a new, or to modify an existing electric power transmission line shall submit a report to the Department and to the Mayor of each township to be affected at least 90 days prior to the planned start of construction or modification. The information will be used for a database and shall be a public record. The public shall be notified of the availability of this report by the utilities by following the procedures stipulated in the Administrative Procedures Act. This report shall contain the following information:

1. The highest operating voltage.

2. The anticipated average and maximum current flow per phase and normal flow direction.

3. Physical dimensions of and between all conductors and distance of conductors to earth.

4. A route map based on the New Jersey Plane Coordinates or latitude and longitude background and standardized geographic coordinates of all structure locations in digital form.

5. ROW description including adjacent habitation, schools, and public buildings.

6. The rationale for selecting the particular line design parameters as it relates to magnetic field exposure including the factors used in the determination. It shall include but not be limited to the following:

i. technical factors;

ii. cost trade-offs;

iii. siting that minimizes potential exposure;

iv. calculated values of the magnetic fields under anticipated average and maximum current flow conditions at every 25 foot interval from the centerline, as measured perpendicular thereto, to the edge of the ROW or 100 feet from the centerline, whichever is greater, in accordance with 7:28-44.6 (Computational Methodology).

v. a description of all alternatives considered and why they were rejected; and

vi. a list of other permits required by the Department before constructing the line.

7. Date of anticipated energization.

(b) Any owner seeking to construct a new, or modify an existing single circuit or double circuit electric power transmission line shall select a line design which will reduce the magnetic field by at least 50% of standard horizontal configuration for single circuit lines, standard superbundle configuration for double circuit lines with current flowing from both circuits in the same direction, or standard low reactance configuration for double circuit lines with current from each circuit flowing in opposite directions to the other circuit, as calculated under anticipated average and maximum current flow for every 50 foot interval from the centerline, as measured on a perpendicular thereto, from the centerline to the edge of the ROW or 100 feet from the centerline, whichever is greater.

(c) Any owner may request an exemption from the requirements of the above sections for all or part of a proposed or modified electric power transmission line. However, the owner must provide sufficient information (e.g., economic hardship, substantially reduced exposures) why the requirements cannot or should not be met to allow the Commissioner to make a determination whether such an exemptions should be given.

(d) Any person likely to be affected by the proposed or modified line may request issuance of a more stringent requirement for magnetic field reduction for all or part of a proposed or modified line. However, the person must provide sufficient information demonstrate the uniqueness of all or the specified part of the proposed or modified line (e.g., unusually sensitive population exposure) and must stipulate why and how the requirements should be amended to accommodate their concern. This request must pertain specifically to the line or part of the line in question rather than being a request for a reevaluation of the entire regulation, which can be addressed through normal requests to the Commission. These stipulations will provide grounds for the Commissioner to consider such requests.

7:28-44.4 Procedures for New and Modified Electric Power Subtransmission Lines

(a) Any owner seeking to construct a new, or to modify an existing electric power subtransmission line shall submit a report to the Department and to the Mayor of each township to be affected at least 90 days prior to the planned start of construction or modification. The information will be used for a database and shall be a public record. This report shall contain the following information:

1. The highest operating voltage.

2. The anticipated average and maximum current flow per phase and normal flow direction.

3. Physical dimensions of and between all conductors and distance of conductors to earth.

4. A route map based on the New Jersey Plane Coordinate system or latitude and longitude and standardized geographic coordinates of all structure locations in digital form.

5. Calculated values of the magnetic fields under anticipated average and maximum current flow conditions at every 25 foot interval from the centerline, as measured perpendicular thereto, to the edge of the ROW or 100 feet from the centerline, whichever is greater, in accordance with 7:28-44.6 (Computational Methodology).

6. Date of anticipated energization.

7:28-44.5 Measurement Methodology

(a) If measurements are required, they shall be conducted in accordance with the procedures set forth and with instruments conforming to and calibrated in accordance with the IEEE Standard No. 644, Standard Procedures for Measurement of Power Frequency Electric and Magnetic Fields from AC Power Lines, latest revision. Measurements shall be conducted on a fully excited line and recorded continuously over a period of at least 14 days with a sampling rate equal to or greater than one sample per 15 minutes.

(b) Instruments shall have been calibrated within the past 180 days prior to use.

7:28-44.6 Computational Methodology

(a) When computations are performed to determine the electric and magnetic fields, the following input data shall be used:

1. The highest operating voltage and the MCR (computations shall consider phase angles and normal current flow directions).

2. The minimum conductor clearance to the earth.

3. Voltages and currents shall be assumed to be balanced in phase and in magnitude.

(b) The computations shall be conducted with a computer program easily available to and acceptable to the Department.

(c) The computations shall be conducted for the new or modified electric power transmission line or subtransmission line only, without consideration of other existing electric power lines or other sources of 60 Hz magnetic fields.

7:28-44.7 Recreational Areas Within Electric Power Transmission Line ROWs

(a) The construction of new recreational areas within a ROW shall be prohibited after the effective date of this subchapter. Those areas under construction prior to the effective date of this subchapter shall be permitted to have their construction completed.

(b) The owner of the electric power transmission line is responsible for placing signs in any public areas under or abutting ROWs where people congregate such as but not limited to playgrounds, ball fields, and school yards. Each sign shall be placed at the edge of the ROW or the edge of the abutting recreational area acted and refused to allow the signs to be posted. For those situations receiving signs, the signs shall be placed every 100 feet along the perimeter of the entire recreational area provided that any portion of it lies within or abutting the ROWs.

(c) The sign shall be colored as set forth in ANSI Z535.1, American National Standard for Safety Color Code, ANSI Z535.2, The American National Standard for Environmental and Facility Safety Signs, and the Identification of Certain Equipment, latest revision. The sign shall be in block letters of at least 2 inches in height, and sign shall be at least of size 2 feet by 2 feet. It shall be placed on a support at a height of 4 feet from the ground. In addition, the following language shall be used:

                NOTICE

     Electromagnetic fields present at
     this site may have an adverse
     health impact to persons in this
     area.  For further information
     contact the US Environmental
     Protection Agency or your local
     environmental officials.