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Department of Pesticide Regulation

The Great Seal of the State of California
Brian R. Leahy
  Edmund G. Brown Jr.
May 17, 2013
  ENF 13-08
County Agricultural Commissioners




In March 2006, the U.S. Environmental Protection Agency (U.S. EPA) issued an amendment to the Reregistration Eligibility Decision (RED) for Propanil (September 2006). As part of the risk mitigation measures for handlers, the U.S. EPA required all dry formulations to be formulated in closed mixing systems. Beginning with the 2013 use season, all dry formulations of propanil products sold or distributed by registrants must comply with the provisions of the propanil RED.


Two issues concerning the dry formulation were recently brought to our attention:

  1. New technology (closed system) for the transfer of dry formulation from the container to the mix or spray tank, and
  2. Disposal of emptied pesticide containers.

Dry formulations of propanil products (new and existing stock)

Currently there are three dry formulated propanil products registered under the provisions of the propanil RED and six products that could be used under the existing stock provision. The three products with the closed mixing system requirements are:

  • Stam 80 EDF-CA, EPA Reg. No. 71085-38, RiceCo, LLC,
  • SuperWham! 80 EDF-CA, EPA Reg. No. 71085-6, RiceCo, LLC, and
  • Willowood Propanil 80CHS EPA Reg. No. 87290-17, Willowood, LLC

Existing stocks of older labeled products without the closed mixing system requirement may be used by the end-user until such stocks are depleted.

1. Closed system technology for the transfer of dry formulation from the container to the mix or spray tank:

The two registrants, RiceCo, LLC and Willowood, LLC, have taken different approaches to packaging the dry formulations.

Willowood has opted to use the "Lock and Load" technology currently used for products such as Temik® Brand 15G "Lock'n Load" and Thimet® 20-G "Lock'n Load". This technology meets both U.S. EPA and DPR requirements as a closed mixing system.

RiceCo has developed a new closed system technology they call "RiceCo Delivery System I" (RDSI).

The RDSI consists of three parts:

  • A clear 2 inch diameter flexible hose used to the transfer the product,
  • An aluminum "bulk head" fitting attached to the mix/spray tank and connected to one end of the hose, and
  • A product bag connector assembly attached to the other end of the hose. The connector assembly uses an aluminum coupler to be connected to a threaded port attached to a top corner of the product bag. The bag is designed to hold 50 pounds of dry formulated product.

DPR's enforcement staff has received numerous calls from both industry and County personnel expressing concern with this new technology. DPR asks that you monitor any issues that arise this use season pertaining to this new closed system technology so that prior to next season we can share the information with RiceCo and work with them to find solutions.

Please be reminded that any person who improperly uses or alters a closed delivery system that compromises the integrity of the system, does so in violation of Food and Agricultural Code section 12973, use of a pesticide in conflict with its registered labeling.

2. Disposal of emptied pesticide containers.

The Willowood dry formulated product is packaged in a refillable, returnable plastic container. Willowood intends to impose a container deposit on pest control dealers selling their product to encourage return of the emptied containers to the dealer location. Representatives from Willowood have indicated they will implement a container retrieval program where emptied containers will be retrieved from the dealers at specified intervals during the use season.

The RiceCo dry formulated products are packaged in non-refillable bags made of a synthetic material. The following label instructions for container disposal are provided for the RiceCo products, under the label section titled "Container Disposal":

"Nonrefillable container. Do not reuse or refill this container. Completely empty bag into application equipment. Then offer for recycling if available or dispose of empty bag in a sanitary landfill or by incineration, or, if allowed by state and local authorities, by burning. If burned, stay out of smoke."

The following bag disposal options have been identified:

  1. Recycling: Interstate Ag Plastics hopes to develop a plan to recycle these bags, but as of this date, they have yet to confirm that the bags can be safely recycled for another use. If Interstate Ag is successful in their efforts, we encourage this avenue of disposal.
  2. Disposal in a sanitary landfill. RiceCo LLC has informed DPR that Recology Yuba-Sutter, will accept these bags for burial in their landfill providing they are properly emptied . To facilitate collection of the bags, RiceCo intends to work with Recology to establish collection sites for the bags in several locations throughout the rice growing counties. Contrary to earlier information, RiceCo has also confirmed that Recology will not require the bags to be rinsed.
  3. Incineration and burning:DPR's bag disposal policy states that only paper bags (including those with plastic liners) may be burned. Proper incineration at an approved facility may not be a viable option due to storage and transportation issues and the cost to incinerate the bags. In addition, burning on-site of this plastic material may be prohibited in certain areas under the local air quality rules and with recycling as an option, a very poor environmental choice.

Again, please report any problem associated with the use of dry formulations of propanil (including container disposal) to the Enforcement Branch Liaison assigned to your county.

If you have questions, contact the Enforcement Branch Liaison assigned to your county.

Original Signature by:
George Farnsworth
Chief, Enforcement Branch


cc:    Mr. Joe Marade, DPR Agricultural Commissioner Liaison
        Enforcement Branch Liaisons

1001 I Street  ·   P.O. Box 4015  ·  Sacramento, California 95812-4015  ·
A Department of the California Environmental Protection Agency