I have to feed a pump it has a load of 30 amps, is 115 volts and is located 1300 feet.

You have not given us all the info we would need to be accurate by try this calculator for yourself. Voltage Drop Calculator 2 awg aluminium would give you about a 9% drop in voltage.

I am not sure how Ballenger came up with 9% Vd with #2 Al.

Using the same calculator I arrive at 17.7 % Vd using #2 Al at 120 volts, 30 amp load, 1300 feet.

Recommended voltage drop is 3%, and I arrive at needing 1000 MCM Al wire ,using this calculator:

Voltage Drop Calculator

In any case, you need to look into using transformers at both ends to step up to a higher voltage at the feed end and as tep down transformer at the load end.

Trying to deliver 120 volts 1300 feet is not practical.