2.6 Container Rinsing, Rinsate & Excess Pesticide Disposal
Key Takeaways
- Triple rinsing and pressure rinsing both aim at the same standard - a container clean enough that the remaining residue is negligible - and rinsate must always be added back to the spray tank and applied to a labelled site.
- Triple rinsing means filling the empty container 10 to 20 percent full, replacing the cap, shaking or rolling it, draining for 30 seconds into the tank, and repeating three times; pressure rinsing takes about 30 seconds with a nozzle probe through the container wall.
- Rinse immediately after emptying, while residue is still wet - a container left to dry cannot be brought back to a rinsed standard.
- A properly rinsed, punctured, non-refillable plastic container is accepted by agricultural container recycling programs; open burning and on-farm burial of pesticide containers are not acceptable disposal.
- Excess diluted spray is best applied to a labelled site at or below the labelled rate; unusable concentrate is a hazardous waste question for the Department and the state environmental agency, never a pour-out.
2.6 Container Rinsing, Rinsate & Excess Pesticide Disposal
Core Concept: An "empty" pesticide container is not empty. Depending on formulation, 1 to 5 percent of the original contents clings to the walls - enough that an unrinsed 2.5-gallon jug can hold a meaningful dose of concentrate. Arkansas has adopted the federal container and containment rule at 40 C.F.R. pt. 165, subparts A through E by reference in 2 CAR Sec. 72-107, so container handling is state-enforceable, not merely a label suggestion.
The Timing Rule Comes First
Rinse immediately after emptying, while the residue is still wet. This is the single most important sentence in the topic. Once residue dries on the interior wall, no amount of later rinsing brings the container back to a rinsed standard, and the container can no longer be legally offered for recycling or disposal as a rinsed container. The practical implication is that rinsing is part of the mixing and loading operation, done at the tank, not a chore for the end of the season.
Triple Rinsing
- Empty the container into the spray tank and let it drain for 30 seconds after the flow drops to drips.
- Fill the container 10 to 20 percent full with clean water or the carrier.
- Replace the cap and shake, roll, or invert so the rinse water contacts every interior surface, including the shoulders and the handle void.
- Pour the rinsate into the spray tank and drain for another 30 seconds.
- Repeat steps 2 through 4 two more times - three rinses total.
- Puncture the container so it cannot be reused, and store it out of the weather for recycling or disposal.
Pressure Rinsing
A pressure rinse nozzle is a pointed probe that is pushed through the bottom or side wall of the container while the container drains into the tank.
- Empty and drain the container for 30 seconds.
- Insert the pressure rinse nozzle through the container wall.
- Rinse for at least 30 seconds, directing the spray around the interior surfaces.
- Let the rinsate drain fully into the spray tank.
Pressure rinsing is faster, uses less water, and produces a container that is already punctured - which satisfies the "render unusable" step in one motion. It is the preferred method for most operations.
| Triple rinse | Pressure rinse | |
|---|---|---|
| Water use | Higher - three fills | Lower |
| Time per container | Longer | ~30 seconds |
| Puncturing | Separate step | Built in |
| Suitable for | Any rigid container, including where no pressure rinser is available | Rigid non-refillable containers |
Rinsate: There Is Only One Right Destination
Rinsate goes into the spray tank and is applied to a site listed on the label, at or below the labelled rate. Rinsate is a dilute pesticide, and applying it as part of the mix is a legal use consistent with the label. Every other destination is wrong:
- Not down a drain, sink, storm sewer, or septic system.
- Not into a ditch, waterway, sinkhole, or abandoned well.
- Not onto bare ground, a driveway, or a mix-load pad without containment.
- Not into the trash.
If rinsate cannot be used immediately, store it in a labelled, closed, compatible container, clearly marked with the product name, and use it as the carrier for the next application of the same product. Rinsate from a different product may not be dumped into an unrelated tank mix.
Containers Themselves
- Non-refillable rigid plastic containers that have been properly rinsed and punctured are accepted by agricultural container recycling programs. Caps, booklets, and labels are removed; containers must be clean, dry, and free of foil seals.
- Refillable bulk containers stay in the registrant's or distributor's system and are returned, not rinsed by the end user.
- Paper and cardboard packaging from dry formulations is emptied completely, and residual dust is shaken into the tank.
- Water-soluble packaging goes into the tank whole - never open it.
- Open burning is not acceptable disposal. Burning pesticide containers can release the active ingredient and combustion products into the air, is prohibited by most labels' storage and disposal statements, and runs into state open-burning restrictions. On-farm burial is likewise not an acceptable practice.
- Follow the container's own Storage and Disposal statement, which is a mandatory part of the label.
Excess Pesticide
| Situation | Correct handling |
|---|---|
| Excess diluted spray mix in the tank | Apply it to a site listed on the label at or below the labelled rate - this is why you calibrate first and mix only what the job needs |
| Excess unusable concentrate | Do not pour out. Contact the Department's Pesticide Section and the state environmental agency; unusable concentrate is handled as a waste, and the label's disposal statement governs |
| Cancelled or unusable product | Same as above; hold it in the original labelled container in secure storage until a disposal route is arranged |
| Contaminated absorbent from a spill | Sweep into a labelled, sealable drum; do not wash it into soil or water; dispose of it per the label and state waste rules |
| Contaminated soil from a spill | Excavate and, where the label allows, spread thinly on a labelled use site at a rate that does not exceed the labelled rate |
[!IMPORTANT] Exam Trap: Mix Only What You Need Most items on this topic can be answered from one principle: the best disposal method is not generating the waste. Calibrating accurately and computing the tank mix for the actual acreage means there is no excess to dispose of. When an item offers "apply the leftover mix to a labelled site at or below the labelled rate" against any pour-out, drain, burn, or bury option, the labelled-site application is the answer.
An applicator empties a 2.5-gallon jug of emulsifiable concentrate into the spray tank at 7:00 a.m., sets the jug aside, and plans to rinse all the day's containers at the shop after the last load at 4:00 p.m. What is the problem with this plan?
Which sequence correctly describes triple rinsing a rigid pesticide container?
A grower finishes an application and has 60 gallons of diluted herbicide left in the tank, plus one partially full jug of concentrate that has been discontinued and can no longer be legally used. What is the correct handling for each?