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Topographic Effects <br /> Distances below are measured from the base. <br /> Crest <br /> elev: 521 <br /> dist: 10665 <br /> Site ()Pk/ s/0 OO()JN& O <br /> elev: 408 <br /> x <br /> dist: 5016 ,, \ � <br /> FA) <br /> H/2 <br /> elev: 262 <br /> dist: 1019 �--- <br /> Base �� 20 R+OGE <br /> elev: 3 3D Act 5YM <br /> dist: 0 <br /> Exposure Category B <br /> Height above local ground z= 30 ft <br /> Location Relative to Crest Downwd <br /> Hill Shape 2-D Rdg <br /> Height of Hill H= 518 ft <br /> Distance upwind of the crest to where the <br /> Lh= 9646 ft difference in ground elevation is half of the height <br /> of the hill. <br /> x= 5649 ft Distance upwind (or downwind)from the crest to <br /> Wind Speed-up over Hills, Ridges,and Escarpments <br /> 1) The hill, ridge,or escarpment is isolated and unobstructed upwind by <br /> other similar topographic features of comparable height for 100 times the Controlled <br /> height of the topographic feature or 2 mi., whichever is less. This by. 2-mi True <br /> distance shall be measured horizontally from the point at which the <br /> height H of the hill, ridge, or escarpment is determined. <br /> 2) The hill, ridge,or escarpment protrudes above the height of upwind 2-mi True <br /> terrain features within a 2-mi radius in any quadrant by a factor of two or <br /> 3) The structure is located as shown in Fig. 6-4 in the upper one-half of a <br /> hill or ridge or near the crest of an escarpment. True <br /> 4) H/Lh >= 0.2 H/Lh >= 0.05 False <br /> 5) H is greater than or equal to 15 ft for Exposure C and D and 60 ft for <br /> Exposure B H = 518 True <br /> Topographic factor <br /> If site conditions and locations of structures do not meet all the Kzt- 1.00 <br /> conditions specified in Section 26.8.1 then Kzt = 1.0. - <br /> Otherwise: <br /> Krt= 1.09 K1= 0.07 <br /> K2= 0.61 <br /> K3= 0.99 <br /> Case Studies in Kzt Determination <br />