SU0004916 - Laserfiche WebLink

Home Browse Search

ELECTROMAGNETIC FIELDS Electric and magnetic fields(EMFs)are invisible energy fields that surround any electrical device, _ including electrical transmission lines. Together these fields are called EMFs. Electric and magnetic energy travels in waves that are commonly referred to as electromagnetic radiation or radiofrequency radiation.EMF indicates the presence of electromagnetic or radiofrequency energy.There are several forms of EMFs,depending on the wavelength and frequency of the radiation.The frequency is usually expressed in terms of a unit called the hertz(Hz).One million hertz is known as a megahertz(MHz).The different forms of EMFs are produced by a variety of sources, including electrical energy facilities.EMFs may also be differentiated based on the ability of the particular EMF to cause ionization,a process that can produce molecular changes that can lead to damage in biological tissue,including genetic material. Changes in genetic material may be a cause of cancer.Those types of electromagnetic radiation with enough energy to ionize biological material include X-radiation(I trillion MHz)and gamma radiation (FCC 1999). All types of electric energy facilities and appliances generate EMFs.In part because of their visibility in areas of human habitation, electric energy transmission facilities generate the greatest public concern. Electric energy facilities generate EMFs at a frequency of 60 Hz.At this frequency,the EMF is considered nonionizing and is not expected to cause molecular changes that lead to the damage of body tissue(Moulder 2003).Once emitted from the source,an EMF dissipates in a circular pattern and weakens with distance from the emitting source. Electrical fields are shielded or weakened by materials that conduct electricity(including trees,buildings, and human skin).Magnetic fields pass through most materials and are therefore more difficult to shield(California Public Utilities Commission [CPUC] 2003). A variety of epidemiological and laboratory studies,including those sponsored and funded by international,federal, and state organizations and agencies,have been carried out regarding EMF exposure and its potential human health risks.With regard to electric energy facilities,a connection between exposure to the type of EMF generated by electric energy facilities and childhood cancer(e.g., leukemia)has been suggested.However, studies have not concluded that there is such a connection. A 75-foot-wide PG&E electrical easement,known as the Rio Oso—Tesla easement containing a 230-kVA overhead electric transmission lines,bisects the College Park site.This transmission line could represent a potential source of EMFs at the project site. 4.9.2 REGULATORY SETTING FEDERAL REGULATIONS Many federal agencies regulate hazardous materials.These include such agencies as the U.S. Environmental Protection Agency(EPA),the Occupational Safety and Health Administration(OSHA), the Nuclear Regulatory Commission(NRC),the U.S.Department of Transportation(DOT),and the National Institute of Health(NIM.The following represents the primary federal laws,regulations,and guidelines governing hazardous materials: Federal Water Pollution Control Act Clean Air Act Occupational Safety and Health Act Federal Insecticide,Fungicide, and Rodenticide Act Comprehensive Environmental Response Compensation and Liability Act(CERCLA) Guidelines for Carcinogens and Biohazards College Park at Mountain House Specific Plan III Draft EIR EDAW San Joaquin County 4.9-13 Public Health and Safety