Unless you want your yard turned into a hazardous waste site, your choices for getting rid of Ants completely is quite limited.
If you dig Ants up and throw the dirt somewhere else, they build their nest in the new spot. If you stir the dirt up and leave it in place, they frantically work to rebuild their nest. If you spray the nest with insecticide, within three days (or less), a new hatch happens, and the Ants go about their business as if nothing happened. Here are two safe options to get rid of pesky Ants forever.
The most difficult but cheapest way to rid yourself of Ants is as follows: Dig them up and place the dirt in a large bucket(s). Once done, fill the bucket(s) with water over the level of the dirt. Stir the dirt and add water as needed.
Ant’s are programmed to dig downward, and are rarely able to climb up a buckets sides. Ants will climb onto grass blades and twigs. If there are any grass blades or twigs in the bucket, remove them. As water covers the dirt, Ants drown. Hours later or the next day pour the mud back where the hill is. This will help kill any remaining Ants and Ant Eggs that were missed.
You may have to repeat this cycle a few times to kill all the Ants. Caution – If you let the bucket sit for a longer period of time, it smells pretty bad. Raw Sewage and other unidentifiable stink comes to mind.
A second safe and easy method is to buy powdered, “Roach Killer”, or “Twenty Mule Team Borax” from the laundry soap aisle. They both are made of Borax. Borax is a mineral with sharp points. Borax gets in the Ants joints and punctures the shell. The Ants then dehydrate. Sprinkle the powder on and around the holes of the Ant hill, and keep the area dry.
Borax when placed in contact with water dissolves and is harmless to Ants. This is why you want to keep the Ant Hill dry.
By the next day, all or most of the Ants should be gone. Repeat every two days as there will be Ant eggs hatching and restarting the colony. After about ten days of powdering the Ant Hill, all Ants should be gone.