"For example, the proposed elevated alignment through downtown San Mateo would require lowering 1st, 2nd, 3rd, 4th, 5th and 9th avenues, with extreme community impact, because (a) the grade is 0.8%, even less than the specification, and (b) there is a requirement to return to grade level before the curve into Hayward Park to avoid having a vertical curve in a horizontal spiral, a track geometry com" . . . . .