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Table 14: Calculated Magnetic Fields (mG) for Proposed Orono 115 kV Transmission Line <br />(3.28 feet above ground) <br />Segment <br />System <br />Condition <br />Current <br />(Amps) <br />Distance to Proposed Centerline (feet) <br />-300 <br />-200 <br />-100 <br />-75 <br />-50 <br />-25 <br />0 <br />25 <br />50 <br />75 <br />100 <br />200 <br />300 <br />Single Pole <br />Peak <br />250 <br />0.44 <br />0.95 <br />3.14 <br />4.83 <br />8.04 <br />14.30 <br />22.62 <br />19.15 <br />10.94 <br />6.32 <br />3.95 <br />1.09 <br />0.49 <br />H -Post Vertical <br />115 kV Single Circuit <br />Average <br />150 <br />0.26 <br />0.57 <br />1.89 <br />2.90 <br />4.82 <br />8.58 <br />13.57 <br />11.49 <br />6.37 <br />3.79 <br />2.37 <br />0.65 <br />0.29 <br />Single Pole Davit Arm <br />Peak <br />250 <br />0.04 <br />0.11 <br />0.69 <br />1.38 <br />3.18 <br />7.86 <br />12.82 <br />7.74 <br />3.08 <br />1.33 <br />0.66 <br />0.10 <br />0.04 <br />115 kV/ 115kV Double <br />Circuit <br />Average <br />150 <br />0.02 <br />0.07 <br />0.42 <br />0.83 <br />1.91 <br />4.72 <br />7.69 <br />4.64 <br />1.85 <br />0.80 <br />0.39 <br />0.06 <br />0.02 <br />Single Pole Davit Arm <br />115 kV/ 115kV Double <br />Circuit <br />Peak <br />250 <br />0.85 <br />1.57 <br />5.06 <br />8.37 <br />16.37 <br />39.44 <br />69.82 <br />35.80 <br />12.38 <br />5.22 <br />2.60 <br />0.40 <br />0.21 <br />w/ Dist. Under Build <br />Average <br />150 <br />0.81 <br />1.50 <br />4.77 <br />7.84 <br />15.28 <br />37.17 <br />67.02 <br />34.09 <br />11.81 <br />5.08 <br />2.61 <br />0.45 <br />0.22 <br />Single Poleeak <br />250 <br />0.44 <br />1.00 <br />3.91 <br />6.64 <br />12.95 <br />27.41 <br />38.42 <br />27.68 <br />13.22 <br />6.85 <br />4.08 <br />1.09 <br />0.50 <br />Y -Frame <br />115 kV Single Circuit�Apyerage <br />150 <br />0.26 <br />0.60 <br />2.35 <br />3.99 <br />7.79 <br />16.67 <br />24.0 <br />16.84 <br />7.95 <br />4.11 <br />2.45 <br />0.66 <br />0.30 <br />Note: The assumed peak and average line loading assumed for these calculations is the estimated flow of 50WA. <br />Source: Xcel Energy, June 7, 2011; Xcel Energy, personal communication, November 22, 2011 <br />The maximum estimated magnetic field generated by the proposed transmission line would be 38.42 <br />mG directly below a 115 kV/ 115 kV double -circuit transmission centerline at 3.28 feet above <br />ground, significantly below the 830 mG general public magnetic field guideline established by <br />ICNIRP. The right-of-way required for the proposed project is 75 feet (37.5 feet on each side of <br />centerline); the highest estimated magnetic field at a distance of 75 feet from the transmission line <br />centerline would be approximately 1.3 to 1.4 mG. At 300 feet from the transmission centerline the <br />magnetic field level drops to a maximum of 0.5 mG, at the lower end of the average background <br />magnetic field of a typical home of 0.5 mG to 4 mG (EPA, 1992). <br />Based upon current scientific evidence, no adverse effects from electric fields or magnetic fields on <br />health are expected for persons living or working at locations along or near the proposed project. <br />The Commission has consistently found that there is insufficient evidence to demonstrate a causal <br />relationship between EMF exposure and any adverse human health effects. Below are some <br />references to recent Commission proceedings relating to high-voltage transmission lines and the <br />issue of electric fields and magnetic fields: <br />120. The absence of any demonstrated impact by electric field and magnetic field exposure supports the <br />conclusion that there is no demonstrated impact on human health and safety. No adverse effectsfrom electric <br />fields and magnetic fields on health are expected forpersons living or working at locations along or near the <br />proposed Priecf (Minnesota Public Utilities Commission, 2010, Finding 120) <br />40. The issue of electric and magnetic fields was discussed in the environmental assessment. A number <br />of national and international health agencies (The Minnesota Department of Health, The World Health <br />Organisation, The National Institute of Environmental Health Sciences have generally concluded in their <br />research that there is insufficient evidence to prove a connection between electric and magnetic fields exposure <br />and health effects. Research has not been able to establish a cause and effect relationship between exposure to <br />magnetic fields and human disease, nor a plausible biological mechanism by which exposure to electric and <br />magnetic fields could cause disease. No Minnesota regulations have been established pertaining to magnetic <br />Environmental Assessment <br />PUC Docket E002/TL-11-223 Page 36 <br />