Spanish to English Tech/Engineering Ships, Sailing, Maritime Muelles, Puertos, terminales

Context:

Abastecimiento de naves: no tiene grifos para aguada, sólo podrá efectuar a través de camiones algibes; para faenas de combustibles por camiones con una capacidad de entrega de 15 ton./hora, por estanque del sitio entrega de 20 ton./hora.

I had problems with the spanish writing of this document all throughout the translation cause it doesn't seem to be so right. I actually couln't make sense of this paragraph from: " ; para faenas...." onwards since punctuation makes it confusing, at least to me. In what I'm asking, does Por estanque mean 'per' or is it 'by means of' as in por camiones? Can anyone help?