Giardia is a parasite that infects the intestines of animals. The single-celled organism, or protozoan, causes cysts to break out on mammals' skin. If your dog has giardia, the dog can transfer the parasite to grass in a dog run. Getting rid of giardia in a grass dog run is nearly impossible, but you can quarantine your grassy space and kennel to do a thorough disinfection.
Quarantine all dogs in your kennel that are displaying giardia cysts. Do not take any new dogs into your kennel until two weeks after your disinfection process.
Disinfect all the kneels with a cleaner made with quaternary ammonium compounds. Apply the cleaner, and leave it for 30 minutes. Wash off the cleaner thoroughly with water.
Quarantine the kennels with grass runs. Do not open them for at least one month since the last infected dog used the kennel space. It is nearly impossible to get giardia out of grass. You must remove the source -- i.e., the infected dog -- and give the grass time to rehabilitate and return to normal.