How to Clean Plastic Herbicide Barrels
- 1). Dispose of any herbicide remaining in the plastic barrel, preferably in the area where you used the herbicide or in an area that is safe for disposal and does not drain into the water system.
- 2). Rinse out the plastic barrel with warm water. Use a hose or a bucket to flush the outside of the barrel with water in case any of the herbicide spilled there. Complete this rinse in the same place that you flushed out the last of the herbicide.
- 3). Fill your plastic barrel with fresh water and ammonia. The University of Missouri recommends adding 1 gallon of ammonia for every 25 gallons your herbicide barrel can hold. Leave the ammonia and water solution in the herbicide barrel overnight.
- 4). Flush the ammonia and water solution out of the plastic barrel.
- 5). Scrub the outside of the tank with an ammonia and water solution, including the outside of the spigot. Use a scrub brush to apply this solution, and use 25 oz. of ammonia per gallon of water. Wear work gloves to protect your hands.
- 6). Spray down the outside of the barrel with a hose to remove traces of the ammonia. Rinse the inside of the barrel by filling it with fresh water, then letting it drain. Fill the barrel once more with fresh water, then let it drain out to ensure the tank is free of ammonia traces.
- 7). Invert the barrel on an elevated platform and allow it to air dry. Your barrel can be re-used for another herbicide, recycled or put into general storage.
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