1993 Chevy S-10 heater core hose

That should be the return from the heater core. If there is enought hose there you can drain some fluid out until it is lower than the hose and disconnect it. Then cut off appox a ahlf to three couters of an inch and then reinstall it. The probability is that where the hose slips on the housing is getting weak and some hoses get pinhole leaks when they are getting weak. The best thing is to get a new hose and install it but a quick fix is just cutting the end of the hose off.