You will need:
--a 5 gallon drink cooler (I found that the Rubbermaid cooler looked more like a drum than the Igloo brand)
--plastic-adhesive spray paint in your base color (I used black)
--a string of battery powered LED mini-lights (can be white or the color you want your waste to be)
--newspaper or a similar bendable material (such as craft foam)
--tape (I used both duct tape and masking tape)
--plastic grocery bag
Step 1: Building the "lid"
Start by cutting two circles out of cardboard the size of (or slightly larger than) your lid. One will be the actual lid and the other will be a false lid.
Using the newspaper or other bendable material, create a lip around one of the cardboard lids. The easiest way I found to do this was to fold the newspaper so it was several layers thick at the correct width, then taping it around the cooler's plastic lid so I knew it would fit.
In order to get an appropriate texture later on that would also prevent the paper and cardboard from warping I covered it all in duct tape. You may want to use something else that will cover it more rather than in small strips, but for a small decor project it worked well enough for me.
Step 2: Base-painting the "drum"
Make sure all surfaces that will be coming in contact with the drink (insides, dispenser) are covered so they do not get painted. For the cooler I had, I simply left the plastic lid on and covered the dispenser in masking tape.
Paint the cooler and lids with your spray paint following the directions on the can.
Step 3: Building That "toxic Glow"
In order to have the foam glow on the inside I decided to use a string of battery-powered LED mini-lights. This way the battery pack could be hidden under the false lid and there would be no worrying about cords.
Arrange the lights as you think you will want the foam to look, and tape them into place. After I put the foam on I realized I should have put fewer lights above the level of the rim and should have put more on the outside near the top, which you may want to take into account when arranging yours.
Step 4: Building the "waste"
In order to make sure the top fake lid does not stick to the foam, hold it tightly in a plastic bag with the battery pack inside to accomodate for the room it will need.
Holding the lid at the angle you want it to sit at, fill the open crack up with foam making sure it covers all the bulbs. You may have to hold it for a little bit as the foam dries but eventually can remove it so that all the foam will dry.
Step 5: Add Finishing Touches
Paint your waste your chosen color. I went with green, but any color will do. (My lights were white because I could not find green, but with the foam and the paint it still glows green.)
Remove all the extra tape on your cooler such as under the foam and on the spout.
Step 6: Making Toxic Waste (the Drink)
1 part vodka
4 parts Mountain Dew
Blue Raspberry Koolaid Mix
Fill 'er up, turn on the lights and enjoy your (only slightly) Toxic Waste!
(Unfortunately my camera died so I don't have any pictures of the drinks or the prop when it was lit up. As soon as I get it fixed I will add one!)