Mothballs are extremely toxic, and I'd recommend keeping them out of your garden, out of hour home, and out of your life completely. If you can retrieve them from your garden, do so using disposable gloves. The gloves and mothballs should be disposed of at your local household toxic waste site. And now, for some suggestions to control your chipmunks... First, if you have bird feeders, avoid filling them with large seeds like peanuts, sunflower seeds, and safflower seeds during the summer months. Smaller seed like niger and millet are fine. The larger seeds and nuts are tasty treat that may attract chipmunks and boost your local population. There are poison pellets on the market for chipmunks, and mixing them with a dab of peanut butter can make them more attractive. Using poisons in your garden always creates the risk that some critter (including pets and young children) may ingest them, so you'll have to be careful about it. You may consider trapping the little guys with either live traps or rat-sized snap traps. Bait them with peanuts or peanut butter and place them near where you believe the chipmunks are living. If you use a live trap, you'll have to relocate them at least five miles from your home.