I'm not sure what "área técnica" refers to in the context of an army. If you say "technical support", it makes me think of I.T., and limits that área to just the computer help desk. I have a feeling, though, that it's more broad than that.
Do you have any additional background details about the source text that might shed some light on the phrase or its usage?
Recuerda que cuando una plabra de género femenino comienza por "a" o "ha" tónica el arículo "la" cambia a "el", siempre qu no haya otra palabra entre el artículo y la que empieza por "a" tónica.
Del = de+el