Agenda - Council - 06/25/2013 - Laserfiche WebLink

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Enterprise Park to Crooked Lake 115 kV Transmission Line March 2012 Environmental Assessment construction of the County Road 116 bridge over the Rum River. Despite the 1989 survey, portions of the island remain undisturbed and there is potential for cultural sites to exist based on the site's proximity to the Mississippi and Rum Rivers. Due to this potential for cultural resources, a Phase I Archaeological Reconnaissance Survey is recommended should construction plans involve ground disturbance of previously undisturbed areas. Mitigation — Archaeological and Historic Resources . The Applicant has stated it will conduct a windshield survey of previously undisturbed areas. When the Route is surveyed and pole locations identified, recommendations from the windshield survey will be taken into consideration. After pole locations are identified, the Applicant will consult with MHS to determine if any additional survey work needs to be conducted. If any archaeological sites are identified during placement of the poles along the permitted Route, construction work will be stopped and MHS staff consulted as to how to proceed. 5.1.6. Safety and Health Potential safety and health impacts from construction and operation of the Project include Electric and Magnetic Fields (EMFs); Interference with Implantable Medical Devices; and Stray and Induced Voltage. Electric and Magnetic Fields (EMF) EMFs are invisible regions of force resulting from the presence of electricity. Naturally occurring EMFs are caused by the earth's weather and geomagnetic field. Man-made EMFs are caused from electrical devices and found wherever people use electricity. EMFs are characterized and distinguished by their frequencies, which is measured by the rate at which the fields change direction each second. All power lines within the United States have a frequency equivalent to 60 cycles per second, defined as 60 Hertz (Hz). EMFs at this frequency level and within the range of 3 - 3,000 Hz are considered to be Extremely Low Frequency (ELF) EMFs. Electric fields are created by the electric charge (i.e., voltage) on a conductor (e.g., a transmission line). Electric fields are solely dependent upon the voltage of a conductor, not the actual flow of electricity (i.e., current). Electric field strength is measured in kilovolts per meter (kV/m). The strength of an electric field decreases rapidly as the distance from the source increases. Electric fields are easily shielded or weakened by most objects and material, such as trees, buildings, and even human skin. Although there is no federal regulation, the Minnesota Public Utilities Commission has imposed a permit condition of 8 kV/m for the maximum electric field for previously permitted high voltage transmission lines (HVTLs) (measured at centerline and at 1 meter 32