From your location and the description of a “large” hill of red ants, I suspect that you have imported red fire ants. So before you through your back out schlepping boiling water, be advised that the vertical tunnels extend all the way to the permanent water table. Also on a large fire ant colony the horizontal tunnels may cover an acre or more, so good luck with the water cure. Monkeying around with the ants’ mound is a sure way to encourage the ants to relocate the mound, sometimes as far as 20 feet away but the direction of the move is up to the ants. It is even possible to force the mound across property lines in a subdivision but this is neither a way to manage or to control fire ants.
Here is the truth about fire ant cures or non cures from Organic Gardening.
 
good luck with your ant problem.
 
http://www.organicgardening.com/learn-and-grow/fire-ant-control
Bucketing fire ant colonies
“This is one of the simplest ways of dealing with one or two problem colonies. Basically, the procedure is to rapidly dig the mound and a foot or so of soil under the mound and dump it into one or several large buckets 
….”
Oh boy!!! Please, Please, don’t forget to leave the video camera running when you "bucket" your fire ants so that we can all have a laugh at your expense.
 
Hot water
“Pouring hot water on the mounds is effective and environmentally friendly, but may require 3 or 4 applications to kill the colony. Water should be at least scalding hot, but does not need to be boiling. This works best when you use 3 to 4 gallons of water in each application…
”
 
Corn grits
“The theory is that the fire ants will eat the dry corn grits, drink some water, and then die as the corn grits expand inside them. The image of greedy little ants exploding like popcorn inside their mounds is very compelling. The problem is that fire ant workers only drink liquids; they are incapable of ingesting solids. Fire ant larvae will eat solid food, but they chew it up and mix it with saliva just like we do….
”
 
This old wives tail may have got started by Ann Landers’ advise to young wives to not let people toss rice at their weddings because the rice would swell up in birds’ wee stomachs causing the death of everything from chickens to chickadees. Or it could be the fact that hominy grits has long been used as a carried for fire ant insecticides as the insecticide laced grits are carried into the colony by the workers and fed to the larva and then the insecticide kills the adult ants' food supply.
 
At any rate all classes of fire ants queens, workers, guards, and warriors are completely dependent on the ant larva for their liquid food supply. This is why it is important to start killing fire ant mounds from the bottom up because killing the larva is the key to exterminating the whole colony by way of starvation.
 
Straw itch mites
“Some studies have shown moderate benefits from releasing these beneficial mites, but other studies have found none. However, the most dramatic effect has been the large rashes that researchers have gotten from some of the stray mites that they were releasing. Ooh, itchy, itchy, ITCHY!
”
 
I won’t go into Diatomaceous Earth except to say that Mississippi is full of the stuff and the state has a very respectable imported fire ant population as well. Besides, tossing fire ants into diatomaceous earth or rather tossing diatomaceous earth onto imported red fire ants is too much like the old Walt Disney tail about Brier Fox and Brier Bear pitching ’Brier Rabbet “In that there brier patch.”