Won't be intercoolers with the volumes described. Intercoolers only collect oil if, a) PCV system isn't scavenging combustion blow-by well enough and it is then condensing at the low point of the charge line, or thr seals on a turbo are worn out and allowing blow-by in to the intake system. It is normal for a bit if oil to leak out when you remove the lower intercooler hose due to oil ladden vapour in thr intake tract, but leaking on on the ground is not normal and suggests worn turbo.
From what the OP described, it sounds like back if engine are and not front.