2004 ford Taurus

That's the side the degas bottle is on, so it may be overheating forcing coolant out the overflow. Coolant can also drip from the condensation drain tube from the heater box if the heater core is leaking. You'll have to look and see where the coolant is coming from, and check the coolant level. The right side of the motor is where the water pump is as well, plus the heater hoses are on the right. So check all of those for leaks. If you're running hot it might be a bad thermostat, but you'll have to troubleshoot what is causing the overheating.