6.4 Pesticide Storage, Disposal & Security

Why Storage and Disposal Matter

How an applicator stores and disposes of a pesticide is as much a regulatory question as how it is applied. A poorly sited, unlocked, or unventilated storage is a point-source contamination risk for groundwater and a fire and poisoning hazard for the community. A dumped container or a poured-out concentrate is a hazardous-waste violation under both federal and Michigan law. The exam treats storage, disposal, and security as a single integrated topic because the same facility decisions affect all three: where you store determines how vulnerable you are to spills, theft, and environmental release.

Proper Storage Conditions

A compliant pesticide storage facility in Michigan should meet all of the following:

• Locked and access-controlled. Restricted-use pesticides must be stored where unauthorized people cannot reach them. Keep a current inventory and limit key access to trained, certified applicators.
• Ventilated. Pesticide vapors and fumes can accumulate to dangerous levels in a sealed room. Mechanical ventilation or a passive vent system that exchanges air to the exterior is required; never store pesticides in a building that shares return air with living or office space.
• Temperature-controlled. Extreme heat can cause containers to bulge or rupture and can degrade active ingredients; extreme cold can cause some liquids to separate or freeze. Follow label storage-temperature limits; keep the storage above freezing and out of direct sun.
• Dry. Moisture rusts metal containers, degrades paper bags, and can leach pesticide from damaged packaging. Keep the floor dry and address any water entry.
• Separate from food, feed, and PPE. Never store pesticides in the same room or on the same shelves as food, animal feed, seed, or personal protective equipment. Cross-contamination from a leak is a serious exposure risk.
• Signed. A visible "Pesticide Storage" sign (and where restricted-use products are stored, a warning sign) on the exterior door alerts emergency responders and keeps people out.
• Spill-containment ready. Keep absorbent material (vermiculite, activated carbon, or commercial pads), a shovel, and a drum or container for recovered material on hand, in or immediately next to the storage.
• Sited away from water. Michigan best practice is at least 100 feet from a drinking-water well and 50 feet from surface water; some labels require more. Never store in a well pit or a building with a floor drain that leads to a sewer or septic system.

Inventory and Security

Agricultural security is the recognition that pesticides — especially certain restricted-use insecticides and fumigants — can be stolen and diverted for illicit use. After 9/11, the EPA and state regulators made security a baseline expectation for pesticide dealers and applicators. Practical security measures include:

• Maintaining a written inventory of every product, with quantities and dates of acquisition; reconcile the inventory at least annually.
• Storing restricted-use pesticides in a separate, locked area within the storage, with access limited to certified applicators.
• Inspecting the storage regularly for signs of tampering, leaks, or theft.
• Reporting any theft or unexplained loss of a restricted-use pesticide to MDARD and to local law enforcement immediately. (Michigan requires reporting under Part 83; the federal requirement also applies for certain regulated products.)
• Securing the facility against vandalism — fences, lighting, and locked doors are standard.
• Controlling the chain of custody during transportation. Do not leave an unattended loaded sprayer in an unsecured area, and never transport pesticides in the passenger compartment of a vehicle.

Disposal of Empty Containers

An empty pesticide container is not truly empty until it has been triple-rinsed (or pressure-rinsed) according to label instructions. Triple-rinsing means draining the container, filling it about one-fifth full of water (or the appropriate rinsate), shaking or rolling it to contact all interior surfaces, draining the rinsate into the spray tank, and repeating for a total of three rinses. The rinsate is applied to a labeled site along with the spray mix; it is not poured out.

After triple-rinsing:

• Puncture the container so it cannot be re-used.
• Do not re-use the container for any purpose — not for water, not for feed, not for storage, not for trash. Pesticide residue remains in the plastic even after rinsing.
• Recycle through a Michigan site participating in the Ag Container Recycling Council (ACRC) program. Many county agricultural collection sites and cooperatives accept rinsed, punctured containers.
• If recycling is not available, dispose of the container according to the label and any local hazardous-waste rule — never burn pesticide containers in an open fire or burn barrel, as this releases toxic smoke and is illegal in most of Michigan.

Paper and fiber containers that cannot be rinsed should be emptied as completely as possible, packaged to prevent dust release, and disposed of as the label directs. Never reuse a fiber drum.

Disposal of Unwanted Concentrate and Pesticides

Unwanted pesticides — obsolete products, cancelled registrations, excess concentrate, or material from a previous owner — are hazardous waste and may not be dumped, burned, diluted, or poured down any drain. Disposal options:

• Michigan Clean Sweep programs — Michigan operates agricultural pesticide Clean Sweep collection programs that accept unwanted pesticides from farmers, applicators, and homeowners at no cost or at a modest fee. Collection sites are operated by county and regional agencies with MDARD and EGLE coordination. Clean Sweep is the standard, recommended route for getting rid of unwanted concentrate.
• Hazardous waste hauler — For commercial applicators with larger quantities or material that is not accepted by Clean Sweep, a licensed hazardous-waste hauler and permitted disposal facility are required. Keep the manifest.
• Never mix unwanted pesticides with other waste streams — mixtures can create more expensive disposal and chemical reactions.

Transportation Security

When moving pesticides from supplier to storage or from storage to the application site:

• Transport in the vehicle's cargo area, never in the passenger compartment.
• Secure containers against tipping and leaking; use bins or secondary containment.
• Carry a copy of the label and SDS for every product being transported.
• Carry spill-control materials in the vehicle.
• Do not leave a vehicle loaded with pesticides unattended in an unsecured location.
• Follow Michigan Department of Transportation and federal requirements for placarding when transporting above threshold quantities of certain products.

Exam Scenario

A common question asks what to do with an empty container that held a liquid pesticide. The correct sequence is: triple-rinse (adding rinsate to the spray tank), puncture the container so it cannot be re-used, and recycle it through an ACRC site or dispose of it according to the label — never re-use it. Another frequent item asks what to do with an outdated jug of restricted-use insecticide concentrate that is no longer needed; the answer is to take it to a Michigan Clean Sweep collection site, not pour it out or burn it. Remember that re-using any pesticide container — even a rinsed one — for anything else is always wrong on the exam.