SDG&E RESPONDS TO QUESTIONS ON ALPINE ELECTROMAGNETIC FIELD (EMF) LEVELS
By Miriam Raftery
Photo: Sunrise Powerlink (left) transmits 500 kilovolts of electricity above ground across most its its route, but was installed underground in Alpine, where it flows beneath the main street in the rural mountain town.
February 20, 2016 (Alpine) – East County Magazine reached out to San Diego Gas & Electric (SDG&E) after reviewing results of two studies measuring electromagnetic field (EMF) levels in Alpine. (The first study, done by an engineer and contractor, found high levels along Alpine Blvd. above the underground Sunrise Powerlink. The second, commissioned by the County Office of Education, measured levels at Alpine Elementary School. It found relatively low levels at most places on the campus, though two outside areas nearest the boulevard were higher, one substantially so. View details here.) Those reports raised concerns among some community members about potential health risks for chlidren, though medical studies have shown conflicting results on this issue.
We asked SDG&E if it has plans to measure EMF levels at other locations, what EMF levels it would consider safe, what fixes or mitigation might be possible, and what EMF research the company supports. Below are our questions and the answers provided by Allison Torres, SDG&E media representative:
Q: Will schools NOT included in the Alpine Unified School District will be tested (i.e. the charter school, the preschool, and the site of the proposed Alpine high school)?
A: SDG&E will perform EMF measurements if requested by a customer, and will take the measurement on the requesting customer’s premises. For customer privacy reasons, the results will only be shared with the customer.
Q: Is the conduit for the underground Powerlink metal or PVC? Is it encased it concrete?
A: The conduit is PVC per SDG&E standard and is encased in concrete.
Q: There seems to be dispute within the medical and regulatory community over what levels of EMFs are safe. What level would SDG&E agree is high enough to be of concern medically?
A: The science and health communities, not SDG&E, are responsible for determining whether an exposure is "high enough to be of concern medically." The CPUC has on several occasions acknowledged that there is no basis for adopting numerical standards for magnetic field exposure. In particular, the CPUC decision approving the Sunrise Powerlink project stated that,
“The Commission has examined EMF impacts in several previous proceedings [CPUC Decisions D.06-01-042 and D.93-11-013]. We found the scientific evidence presented in those proceedings was uncertain as to the possible health effects of EMFs and we did not find it appropriate to adopt any related numerical standards. Because there is no agreement among scientists that exposure to EMF creates any potential health risk, and because CEQA does not define or adopt any standards to address the potential health risk impacts of possible exposure to EMFs, the Commission does not consider magnetic fields in the context of CEQA and determination of environmental impacts.”
Additionally, no California or U.S. Federal Government agency (including the Environmental Protection Agency) has adopted health-based standards for magnetic field exposure, and neither has the World Health Organization.
Although science has been unable to determine whether there are health effects from EMF exposure, we recognize the concerns of our customers. Until research and the scientific community provide greater direction, the company, under the direction and regulation of the California Public Utilities Commission, will continue to take proactive measures to reduce EMF levels whenever possible.
Q: If high levels are found in areas that are of concern, such as inside the school, homes or businesses (after ruling out other causes such as microwaves or computers) what is the level measured inside such locations from Powerlink that would make SDG&E believe that mitigation is needed? What possible fixes are there? The expert I spoke with said there are ways to shield underground lines, so the question is was that done initially, and if so, are there areas that were not adequately shielded that may need a fix?
A: The CPUC EMF Policy requires utilities to identify the no-cost measures undertaken, and the low-cost measures implemented, to reduce the potential EMF impacts. Per this policy, SDG&E applied no-cost reduction measures to the Sunrise Powerlink underground by splitting the bundled phase conductors of each circuit and reverse-phasing the conductors in the conduits. Reversing one set of phase conductors can cause the magnetic fields to partially cancel the fields from the other set, which successfully reduced EMF levels by over 60%.
Q: How does SDG&E support EMF research?
- A few examples of our support include:
- SDG&E supports EMF research by actively participating as a member of the Electric Power Research Institute (EPRI) Electric and Magnetic Fields and Radio-Frequency Health Assessment Program. This program addresses key environmental health and safety issues related to public and worker exposure to electromagnetic field environments associated with electric power system infrastructure.
- EPRI is the sole EMF research entity in the United States that brings together scientists and engineers as well as experts from academia and the industry to conduct research and development relating to the generation, delivery and use of electricity for the benefit of the public.
- SDG&E’s EMF Services, Safety division attends at least two EMF/RF research and informational conferences each year to stay abreast of the current EMF research and developments.
- SDG&E supports EMF research by actively participating as a member of the Electric Power Research Institute (EPRI) Electric and Magnetic Fields and Radio-Frequency Health Assessment Program. This program addresses key environmental health and safety issues related to public and worker exposure to electromagnetic field environments associated with electric power system infrastructure.