Profundidad del agua subterranea (m)
0 - 1.524 = 10
1.524 - 4.572 = 9
4.572 - 9.144 = 7
9.144 - 15.24 = 5
15.24 - 22.86 = 3
22.86 - 30.48 = 2
30.48 - 1000 = 1

Recarga (mm)
0.1 - 50.8 = 1
50.8 - 101.6 = 3
101.6 - 177.8 = 6
177.8 - 254 = 8
254 + = 9


Topografía
0 - 2 = 10
2 - 6 = 9
6 - 12 = 5
12 - 18 = 3
18+ = 1

Conductividad hidraulica (m/d)
0.04 - 0.45 = 1
0.45 - 0.9 = 2
0.9 - 1.35 = 3
1.35 - 3.6 = 4
3.6 - 2.25 = 5
2.25 - 3.6 = 6


Ecuación DRASTC
 ( "D@1" * 5 )  +  ( "R@1" * 4 )  +  ( "A@1" * 3 )  +  ( "S@1" * 2 )  +  ( "T@1" * 1 )  +  ( "C@1" * 3 )