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[GreenYes] Fwd: [USCC] Clopyralid and Composting - USCC Environmental Policy and Regulatory Affairs Committee Position Paper Regulatory Affairs Committee Position Paper

>From: Jim McNelly <>
>Position Paper of the US Composting Council Environmental Policy and 
>Regulatory Affairs Committee
>Submitted to the US Composting Council Board of Directors
>August 24, 2001
>Clopyralid and Composting
>- Dow AgroSciences (Dow) has been marketing products containing a 
>long-lasting herbicide, clopyralid, that has proven to be incompatible 
>with community-scale composting of yard trimmings. The most serious 
>problem appears to be associated with the product Confront, but other 
>products containing clopyralid (or picloram) are also of concern.  Plant 
>residues treated with these products have carried clopyralid into 
>municipal composting systems, leading to unacceptably high concentrations 
>of clopyralid in the resulting compost. In some cases, the levels have 
>been high enough to cause damage to crops grown by users of the compost. 
>Damage from clopyralid-contaminated compost has been documented in 
>Washington, Pennsylvania and New Zealand. Most likely, there are many more 
>unconfirmed incidences.
>- This situation significantly limits the management options for both 
>clopyralid-treated residuals and the compost produced from them. It 
>essentially restricts the management of residuals to either reuse them 
>on-site, land apply to the same crop, or dispose as a solid waste in a 
>landfill or incinerator. Disposal is not the normal method of handling for 
>these wastes, and certainly not a desirable method, with at least 37 
>states restricting the disposal of yard trimmings in landfills or 
>incinerators.  In addition to being counter to environmental goals, 
>disposal poses a higher cost for the user. For on-site reuse, there is an 
>unknown effect of herbicide residues that has not been accounted for in 
>re-application instructions. This may result in accumulation and transport 
>of herbicide above and beyond the intended and approved amounts and uses.
>A FLAW IN THE SYSTEM  The label and its implications
>- The residuals management information that Dow supplies for this product 
>is inadequate and inaccurate, failing to provide a clear understanding of 
>appropriate management methods for plant residuals. The current 
>information is misleading in its inference that plant residuals treated 
>with clopyralid can be composted successfully with no negative residual 
>effects if the composting period extends beyond the season in which the 
>residuals are harvested (i.e. effectively for a year). First, this 
>recommendation is a faulty conclusion of the original research conducted 
>for clopyralid (Vandervoort et al, 1997).  While the research did show 
>reductions in the concentrations, the residual levels remaining in the 
>compost at the end of research trial (365 days) would significantly damage 
>non-targeted plants. It did not show levels of remediation that could be 
>consistently safe for general horticultural use of the compost, in even a 
>long term composting scenario.
>-       Secondly the label recommendation is impractical in that it 
>requires a year-long composting period. The statement  "not for use in the 
>same season as applied" might apply to some on-site composting systems, 
>but it is not consistent with common practices in the composting industry. 
>Most facilities in the U.S. have a two to six month residence time. More 
>highly managed facilities have a 20 to 40 day residence time. The 
>composting industry is not going to modify its practices to accommodate 
>the presence of a slowly degrading herbicide.  Significant markets exist 
>for one to five day old compost, applied to fields for grape, berry and 
>rhubarb production. This is done extensively in California and is done in 
>Washington as well.
>-       This dictation of residence time would place an undue burden on 
>the industry to hold onto products that are typically accepted for 
>composting in a community-scale compost system. It is substantially longer 
>than normally required for health and safety for these materials without 
>clopyralid. Thus, the label should instead have a concise and clear 
>statement that these treated plant residuals cannot be placed into a 
>community compost system. The requirement imposed by the current label 
>statement constitutes a unique and harsh burden for composting 
>facilities.  Is Dow prepared to pay the additional land, processing costs, 
>and inventory fees for a longer retention time at the nearly 3,500 
>composting facilities that currently receive grass clippings?. Such 
>compensation should also include the additional  equipment, permit 
>extensions, and water runoff control systems imposed by this extension in 
>time.  We doubt that time alone will adequately reduce the concentration 
>of clopyralid.  The Spokane regional composting facility has over 40,000 
>cubic yards of finished product, held for a year and a half, that still 
>has damaging levels of clopyralid.
>-The composting industry is being harmed because Dow's clopyralid products 
>are causing damage to non-target crops through inappropriate recycling of 
>clopyralid-treated harvested plant residuals into community compost 
>systems, and most likely in home or on-site composting systems. This has 
>become clearly evident in some locations, such as Spokane, WA. The ever 
>increasing reports of "compost killing plants due to herbicides" are 
>further damaging the composting industry as a whole. Dow's lack of clarity 
>in their label instructions regarding appropriate management of harvested 
>plant materials has contributed significantly to this problem. The current 
>label is obscure enough to confuse any reasonable applicator about their 
>obligations for the final disposition of harvested materials. Also there 
>is no effective system in place to provide harvesters recommendations for 
>proper handling of the residuals.
>- Given the situation described above, namely that clopyralid treated 
>residues are compromising the quality and performance of compost and that 
>the current label recommendations are improper, the U.S. Composting 
>Council urges Dow AgroSciences to implement appropriate corrective 
>measures. We suggest the following.
>- Dow should work with the EPA to quickly address the inadequacies of the 
>label instructions for clopyralid to reduce their liabilities and make 
>clear the liabilities of the applicator and the harvester (of plant 
>residues) regarding the proper disposal or recycling of grass clippings or 
>other clopyralid-treated residues that might be applied to on non-targeted 
>-  Dow should investigate approved clopyralid applications, in addition to 
>turf, and the end use of the harvested organic residues from those 
>applications. This includes wheat straw that is used for mushroom 
>cultivation, for example. This by-product from mushroom production is used 
>for horticulture purposes. There have been reports of mushroom compost 
>products hurting plants if not well diluted, this is usually blamed on 
>excessive soluble salt levels, but may possibly be caused by a residual 
>herbicide. Other grain straw that is used for horse bedding or fodder 
>should also be investigated as this product is generally used in 
>agricultural for land application or composted for general horticultural 
>uses. Washington State University (WSU) recently found clopyralid at 
>levels of 200 parts per billion (ppb) in the straw coming from their 
>veterinary medicine facility. Mint is also used as a compost feedstock in 
>Oregon. We are very concerned that this herbicide has widespread use with 
>seeming disregard for its ultimate fate.
>- Any consumer of grain, asparagus, beets, or their by-products (chicken, 
>cow, pig, horse, human, etc.) should be investigated as the amount of 
>clopyralid passing through their systems into their manure and urine, and 
>in the final form of those materials used in general agriculture or 
>horticulture. Dow should focus on the areas of highest use for their 
>products and conduct comparative bioassays with residuals that receive low 
>use. Furthermore that the USCC is concerned that grain is transported over 
>large areas, and that the sources of grain or fodder are important to 
>document for any sampling.
>- Dow should compensate composters and raw residuals applicators for the 
>costs incurred and for damage to customer's crops resulting from 
>clopyralid contamination of compost.
>- Dow should purchase from composters at fair market value any 
>clopyralid-contaminated compost products that cannot be marketed because 
>these products cannot support general plant growth. Many composters are 
>under contractual obligations to supply compost product. Clopyralid 
>contamination would prevent them from meeting their obligations.
>- Dow should compensate organic growers for lost produce markets and loss 
>of organic certification (three years or more) for materials that have 
>been contaminated with clopyralid that have passed onto their land from 
>treated organic residuals. Many composters of organic residuals from urban 
>and rural sources risk losing their organic certification for their 
>products because of the increasingly widespread use of clopyralid. 
>Compensation should include market development costs due to the loss of 
>organic certification and for recertification after a problem with 
>clopyralid is found.
>-  Dow should compensate composters for costs associated with remediation 
>of client's land. For example, WSU is supplying activated charcoal for 
>tying up herbicide residues in their compost to allow further 
>horticultural uses.
>-Dow should consider removing from the approved use list any application 
>that Dow has reason to believe residuals may likely be directed to 
>horticultural or agricultural uses that may damage non-target plants.
>- Dow should fund an independent investigation to determine the extent of 
>the problem of clopyralid (and picloram) contamination at composting 
>facilities. To date, the problem has been documented at only a few 
>facilities but the conceivably the contamination is widespread. Numerous 
>facilities in many regions handle grass clippings, yard trimmings, and 
>agricultural residues that could be carrying significant amounts of 
>clopyralid and picloram. A geographically diverse procedure of sampling, 
>bioassays and analytical chemical tests would do much to put the problem 
>into perspective and provide information that would point to appropriate 
>The USCC believes that damage has already begun to erode the compost 
>industry's hard-won reputation as a source of quality products and as a 
>means to effectively recycle yard trimmings. It may have already damaged 
>the manure and biosolids composting facilities reputations as 
>well.  Composting has been considered as a means to render organic 
>feedstocks safe from herbicide residues. For most herbicides, that still 
>appears to be the case. However, the recent problems with clopyralid and 
>picloram have raised questions that may affect consumer confidence. The 
>USCC believes that Dow's product clopyralid is the first significant 
>threat that has occurred to the composting industry due to its persistence 
>and misleading label. Dow should consider it's responsibility for ensuring 
>the safe disposal of its products and treated residuals. The USCC is 
>willing and able to assist Dow and other horticultural and agricultural 
>chemical companies in future evaluations of the fate and acceptability of 
>products in organic recycling systems. We do not want to have this 
>situation repeated.

Gary Liss
Fax: 916-652-0485

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