Page 2 of 10 Summary This docu m ent announces that the U.S. Environmental Protection Agency (EPA) is proposing to grant a conditional registration under section 3(c)( 7 ) (c) of the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) for the new active ingredient, halauxifen - methyl (met hyl 4 - amino - 3 - chloro - 6 - (4 - chloro - 2 - fluoro - 3 - methoxyphenyl)pyridine - 2 - carboxylate) . Halauxifen - methyl , an herbicide, is formulated as one technical product and two end - use products (GF - 2685 and GF2686 , the latter also referred to as QuelexTM). The product QuelexTM contain s 10.4% halauxifen - methyl and 10% florasulam. The product GF - 2685 contain s 10.4% halauxifen - methyl. The labels specify that halauxifen - methyl is to be applied as a post - emergent herbicide on actively growing wheat, barley and triticale. S ingle or split applications can be made per crop provided there is a 14 - day interval between treatments. Halauxifen - methyl applications are limited to two times per crop per year . Halauxifen - methyl use is intended to control or suppress broadleaf weeds that have been shown to cause significant economic damage through yield losses, such as bedstraw, common chickweed, flixweed, henbit, volunteer flax, horseweed (marestail), lambs quarters and redroot pigweed, including biotypes having shown resistance to a cetolactate synthase ( ALS ) enzyme and glyphosate herbicides. Although halauxifen - methyl is a new active ingredient (a chemistry never before registered in the United States), florasulam , a co - formulated active ingredient in QuelexTM, is a currently registered active ingredient which includes uses on wheat, barley and triticale. Since no new exposures for florasulam are being considered with this registration action, no new assessments were performed for f lorasulam. Therefore, t his do cument is intended to discuss the results of the Agency’s findings on the assessment of the proposed new active ingredient halauxifen - methyl and its use on wheat, barley, and triticale. Background On September 7, 2012, EPA received an application to register products containing the new active ingredient halauxifen - methyl (CAS Number 943831 - 98 - 9), an herbicide for use on wheat, barley, and tritical e from Dow AgroSciences (DAS) . The application also requested the establishment of permanent tolerances for residues resulting from these uses. DAS also submitted applications for simultaneous review to the Pest Management Regulatory Agency (PMRA) of Canada and the Australian Pesticides and Veterinary Medi cines Authority (APVMA). The EPA, PMRA, and APVMA combined scientific and regulatory expertise to conduct a joint review. Each country's team of scientists peer - reviewed the primary reviews of their counterparts. While continuing to consult and coordina te, each country individually developed its own human health and ecological risk assessments in accordance with its Agency’s regulatory and scientific policies . Halauxifen - methyl (also known as XDE - 729 methyl) is a synthetic auxin (HRAC group O, WSSA Group 4) herbicide and the first member of the new arylpicolinate class of chemistry. Halauxifen - methyl readily undergoes rapid de - esterification to its corresponding free acid halauxifen - acid (also known as XDE - 7 29 acid). Halauxifen - methyl , like other synthetic auxins, mimics the plant growth hormone auxin , resulting in the disruption of growth processes inPage 3 of 10 susceptible plants. The product GF 2686, QuelexTM , contains 10.4% halauxifen - methyl and 10% florasulam , giving the product two different modes of action (M O A). Florasulam is an ALS inhibitor (HRAC group B, WSSA Group 2) of the triazolopyrimidine chemical class , which leads to the inhibition of DNA synthesis. The product GF - 2685 will contain 10.4% halauxif en methyl only . DAS submitted two additional end - use products which were later withdrawn, GF 2687 and GF - 2688. The proposed labels specify that halauxifen - methyl is to be applied as a post - emergent herbicide on actively growing wheat, barley and tritic ale at a maximum single application rate of 0.009 1 pounds active ingredient per acre (lbs ai/acre ) . Single or split applications can be made provided there is a 14 - day interval between treatments. Halauxifen - methyl applications may not exceed 0.018 lbs ai/acre per year. The pre - harvest interval (PHI) is 60 days. The pre - grazing interval is 7 days. Additionally, a 21 - day interval must be observed prior to the cutt ing of hay. Evaluation of Risk to Human Health and the Environment In evaluating a pesticide registration application, the EPA assesses a wide variety of exposure information (i.e., where and how the pesticide is used) , environmental fate studies (i.e., how the chemical will move in the environment) and toxicity studies (i.e., effects on humans and other non - target organisms) to determine the likelihood of adverse effects (i.e., risk) from exposures associated with the proposed use of the product. Risk assessments are developed to evaluate the environmental fate of the compound as well as how it might affect a wide range of non - target organisms including humans, terrestrial and aquatic wildlife and plants. On the basis of these assessments, EPA eval uates and , as appropriate, approves language for each pesticide label to ensure the directions for use and safety measures are appropriate to mitigate any potential risk. The pesticide's label helps to communicate essential limitations and mitigations that are necessary for public safety. It is a violation of federal law to use a pesticide in a way that conflicts with the label. Assessment of Risk to Human Health EPA has evaluated the available toxicity data and considered its validity, completeness, and reliability as well as the relationship of the results of the studies to human risk. EPA has also considered available information concerning the variability of th e sensitivities of major identifiable subgroups of consumers, including infants and children. The toxicology database for halauxifen - methyl is considered adequate and no additional data are required at this time. Toxicological Profile Halauxifen - methyl rapidly metabolizes in the liver to XDE - 729 acid. The parent targets the liver, while the acid metabolite causes kidney effects. Due to the distinct toxicities of the two compounds and the unique mode of action ( MOA , activation of liver aryl hydrocarbon receptor, or AhR) for liver toxicity of halauxifen - m ethyl that was identified in mechanistic studies , risk from the two com pounds was assessed separately using distinct endpoints . Based upon review of the database, t here is no evidence of acute dietary toxicity, neurotoxicity , genotoxicity or immunotoxicity for either compound. Neither compound was acutely toxic (Category IV). B othPage 4 of 10 are mild eye irritants (Category III) but not dermal irritants or sensitizers. XDE - 729 acid is classified as “not likely to be carcinogenic to humans.” Halau xifen - methyl is classified as “not likely to be carcinogenic to humans at doses that do not induce Cyp1a1 expression (a biomarker for AhR activation) ,” based on the premise that AhR activation and subsequent promotion of hepatocellular tumors, a well - known non - genotoxic mechanism of liver carcinogenesis, depend upon this molecular initiating event (MIE). Moreover, based on its rapid in vivo metabolism to XDE - 729 acid, halauxifen - methyl is not expected to persist in the body; therefore, progression of liver toxicity (including carcinogenic potential) from sustained A hR activation is not expected. There is no evidence of increased prenatal susceptibility to either compound and no evidence of postnatal susceptibility to XDE - 729 acid . Parental toxicity in the r at two - generation reproductive toxicity study was observed at the highest dose , but no offspring or reproductive toxicity was reported. Specific information on the studies received and the nature of the adverse effects caused by halauxifen - methyl and its m etabolite, XDE - 729 acid, as well as the no - observed adverse - effect - level (NOAEL) and the lowest - observed - adverse - effect - level (LOAEL) from the toxicity studies , can be found at http:// www.regulations.gov in document, “ Halauxifen - methyl

– New Active Ingredient Human Health Risk Assessment for Proposed Uses on Cereal Grains (Barley, Wheat, and Triticale) ” in docket ID number EPA - HQ - OPP - 2012 - 0919. Dietary Assessment Dietary risk estimates for halauxifen - methyl and XDE - 729 acid are well below EPA’s lev el of concern. Quantitative acute dietary exposure and risk assessments are performed for a food - use pesticide if a toxicological study has indicated the possibility of an effect of concern occurring as a result of a 1 - day or single exposure. No such effec ts were identified in the toxicological studies for halauxifen - methyl or XDE - 729 acid; therefore, quantitative acute dietary exposure assessments were unnecessary. In conducting individual chronic dietary exposure assessments for these two compounds, EPA used the food consumption data collected between 2003 and 2008 for USDA’s National Health and Nutrition Survey/What We Eat in America . As to residue levels in food, EPA used tolerance level residues (the highest estimated residue level based on the proposed application rates) and conservative modeled drinking - water estimates, while also assuming that 100 percent of all wheat, barley and triticale acres are treated. No processing factors were used due to the lack of residue concentration in processed commodities. Even while using these highly conservative assumptions , EPA has concluded that chronic exposure to halauxifen - methyl from food and water will u se < 1 % of the chronic population adjusted dos e ( cPAD ) for all infants, the population group receiving the greatest exposure. In addition, EPA has concluded that chronic exposure to XDE - 729 acid from drinking water will also u s e < 1 % of the cPAD for all infants. Therefore, the chronic dietary exposur e and risk estimates do not exceed the Agency’s level of concern ( > 100% of the cPAD). Additional details of this dietary assessment can be found at http://www.regulations.gov in document, “Halauxifen methyl Chronic Aggregate Dietary (Food and Drinking Water) Exposure and Risk Assessment for the Section 3 Registration Action on Barley, Wheat, and Triticale ” in docket ID number EPA - HQ - OPP - 2012 - 0919.Page 5 of 10 Aggregate Risk Assessment Assessment of aggregate risk takes into account the combined risk potential that results from dietary exposure through food and water, as well as any additive residential handler exposures. Since t here are no residential uses for halauxifen - methyl being proposed at this time , the chronic aggregate risk reflects only exposure to p otential residues in food and drinking water. Therefore, the aggregate chronic risk is equal to the chronic dietary risk, which is well below the EPA’s level of concern. Handler and Post - application Exposure Since no short - or intermediate - term dermal e ffects were identified, a quantitative dermal exposure assessment was not conducted. Occupational handler and post - application assessments for halauxifen - methyl are based on inhalation exposures only. Risk estimates based on short and intermediate - term occupational (worker/applicator) inhalation exposure to halauxifen - methyl for handler s (m ixing, loading, and application) are not of concern with baseline attire and personal protective equipment (PPE) f or ground applications and enclosed cockpits for aerial applications. Although a quantitative post - application inhalation exposure assessment was not performed, an inhalation exposure assessment was performed for occupational/commercial handlers. Handler exposure resulting from application of pesticides outdoors is likely to result in higher exposure than post - application exposure. Therefore, it is expected that these handler inhalation exposure estimates would be protective of post - application inhalatio n exposure scenarios. Based on the acute toxicity of halauxifen - methyl, the [156 subpart K] Worker Protection Statement interim restricted entry interval (REI) of 12 hours is adequate to protect agricultural workers from post - application exposures (i.e., entering areas that has been previously treated with halauxifen - methyl). Additional details of this occupational handler and post - application assessment can be found at http://www.regulations.gov in document, “Halauxifen - methyl . Occupational and Resident ial Exposure and Risk Assessment to Support the Registration of the New Active Ingredient on Wheat, Barley, and Triticale. ” in docket ID number EPA - HQ - OPP - 2012 - 0919. Assessment of Ecological Risk Halauxifen - methyl, a methyl ester, undergoes rapid de - esterification to the corresponding free acid (halauxifen - acid; XDE - 729 acid) and is considered moderately mobile. The primary mechanisms of transport of halauxifen - methyl away from the treated field will be spray drift, runoff, and leaching. The specific label language and requirements for the r eduction of these transport pathways are further explained in the “Mitigation and Labeling Requirements” section of this docume nt . Halauxifen - methyl and the XDE - 729 acid are not considered volatile and, therefore, are not likely prone to vapor phase atmospheric transport. In the environment , halauxifen - methyl is characterized as moderately persistent with adjusted half - lives ranging from 9 - 42 days conservatively accounting for the discrepancy between laboratory and field - measured degradation and dissipation.Page 6 of 10 Based on the ecological toxicity data, halauxifen - methyl is not likely to result in direct risk to insects 1 , birds, reptiles, amphibians (terrestrial and aquatic phase) , mammals , fish, aquatic invertebrates, or aquatic nonvascular plants as a result of the proposed use. However, risks to terrestrial, semi - aquatic and aquatic vascular plants were identified, as is expected with an herbicide that has been formulated to target vascular plants . For aerial and ground applications, the expected exposure result s in risk quotients (RQ) that exceed the level of concern (LOC) for many non - target vascular plant species. Though the RQ values range widely based on the type of vascular plant being exposed , the Agency assumes the most conservative estimates when determin ing mitigation measures in order to protect the most sensitive species. Label requirements for keeping the applications on the target area will effectively reduce exposures to these non - target vascular plants. The specific label requirements are further ex plained in the “Mitigation and Labeling Requirements” section of this document . I nformation on the studies received and the nature of the adverse effects caused by halauxifen - methyl and its degradate , XDE - 729 acid can be found at http://www.regulations.go v in document, “Ecological Risk Assessment for the New Herbicide Halauxifen - methyl” in docket ID number EPA - HQ - OPP 2012 - 0919. Other chemicals belonging to the synthetic auxin class of chemistry are considered persistent and have been detected in compost as a result of the composting of agricultural material, including plant material and manure, which contain synthetic auxin residues. Several non - guideline studies were submitted by DAS to evaluate the risk of halauxifen - methyl in compost. These studies attempted to address the potential exposure of non - target plants to halauxifen - methyl in compost by evaluating the degradation kinetics of halauxifen - methyl in compost and conducting bioassay studies with compost 1) generated fro m halauxifen - methyl - treated plant material and 2) compost treated directly with halauxifen - methyl to represent no degradation. Upon review, these studies have been classified as “supplemental,” meaning that there is information that can be used to charact erize the potential risk associated with compost; however, issues with the study methodology and conduct limited the Agency’s ability to rule out the potential of such risk. Though effects were observed in these studies, they could not be directly attribut ed to halauxifen - methyl. However, due to the current uncertainty regarding the potential presence of halauxifen - methyl in compost, l abel mitigation has been identified to effectively remove this exposure pathway by restricting the use of treated plant mate rials in compost . The specific label requirements are further explained in the “Mitigation and Labeling Requirements” section of this document . Benefits Growers throughout the United States have experienced yield and economic losses due to weeds developing resistance to heavily used herbicides. The need for additional tools to manage these resistant weeds has become important as resistance to glyphosate , ALS inhibitors, and other herbicides has become a significant financial, production a nd pest m anagement issue. Wheat

1 The full suite of pollinator studies was not submitted for this chemical in 2012. Current tier I toxicity data on adult bees is adequate for registration and shows no toxicological concern. Further, wheat, barley and triticale are wind pollinated and not attractive to pollinators , therefore there is no expected a dded risk to pollinators . However, it is noted that EPA is moving towards the practice of requiring the full suite of pollinator data for all pesticide active ingredients in the future . Therefore EPA intends to require this data as a condition of registration.Page 7 of 10 and barley are high - valued national agricultural commodit ies and are major U.S. export s. T he 2012 USDA Agriculture Census indicates approximately 85 million acres of wheat were harvested, valued at over 17 billion dollars. Weeds su ch as bedstraw, common chickweed, flixweed, henbit, volunteer flax, horseweed (marestail), lambs quarters and redroot pigweed can be difficult to control during the growing season, particularly those that have shown to develop resistance to ALS inhibitors. The availability of active ingredients of new chemistries (arylpicolinate group in this case) is generally considered beneficial because new chemistries broaden the spectrum of target pests that can be controlled. New chemicals can be helpful in pest - management and resistance - management programs as additional resources for weed control, especially where current treatments are less successful. The proposed registration for halauxifen - methyl includes herbicide resist ance management labeling outlined in PRN 2001 - 5. For instance, the WSSA mode of action group is listed on the label as well as other statements which will help sustain the use of the herbicide. In addition, one of the formulations, Quelex, is itself a com bination of pesticides that contains two different weed control chemicals. This is considered to be a component of a season - long control strategy by extension and crop advisors. The EPA expects h alauxifen - methyl would provide an additional tool for growe rs to include in resistance - management programs, in order to control biotypes of weeds that have shown resistance to other common herbicides, such as glyphosate and ALS inhibitors. The toxicity profile for halauxifen - methyl identifies no risk s of concer n to human health from occu pational or dietary exposure, and may provide a better alternative to older chemistries that require higher levels of risk mitigation practices in order to reduce dietary and occupational exposures. For example, applicators and o ther pesticide handlers of halauxifen - methyl are safe with baseline PPE , compared to currently registered older chemistries whose labels may contain additional PPE . In addition, the time interval that must be observed before re - entering a treated field for various cultural activities, such as scouting for weeds, is much shorter than with some of the older chemistries being used today ; the halauxifen - methyl labels requ ire a 12 - hour re - entry interval (REI) . Additionally, growers will have more flexible crop rotation options with shorter plant - back restrictions compared to ALS inhibitors currently in the marketplace. For instance the plant - back interval for soybeans, cor n and several other crops is 14 days. This provides growers with greater flexibility than many other alternative materials registered for wheat, such as the ALS class of chemicals which tend to have longer plant back terms . With respect to non - target risks, halauxifen - methyl has low toxicity for non - target wildlife , which may provide a better alternative to the comparable products being used on wheat, barley and triticale. Overall, EPA expects that there may be meaningful benefits for halauxifen - methy l for controlling difficult weeds in these crops and also in helping to reduce weed resistance. Regulatory Rationale The database submitted to support the assessments of human health risk and environmental fate and ecological risk is adequate to support the proposed use s and tolerances. There are no risk estimates of concern for human health. Halauxifen - methyl is not likely to result in direct risk to non - target terrestrial animals, including insects, birds, reptiles, terrestrial - phase amphibians, and mam mals, nor to aquatic animals including amphibians, fish, invertebrates, and nonvascular plants. As expected of an herbicide, halauxifen - methyl may pose a risk to terrestrial and aquaticPage 8 of 10 vascular plants. Label language as outlined in the "Mitigation and Labeling Requirements" section below will reduce the risk to these organisms. Mitigation and Labeling Requirements Leaching/Run - off Potential Because of the potential for leaching of halauxifen - methyl and degradates, labels have language including surf ace and ground water advisories that stress the potential for runoff after treatment and descriptions of conditions that may promote leaching to groundwater. “ Groundwater Advisory: This chemical has properties and characteristics associated with chemicals detected in groundwater. The use of this chemical in areas where soils are permeable, particularly where the water table is shallow, may result in groundwater contamination. Surface Water Advisory : This product has a potential for reaching surface water via runoff after application. A level, well - maintained vegetative buffer strip between areas to which this product is applied and surface water features such as ponds, streams, and spr ings, will reduce the potential loading of halauxifen - methyl from runoff water. Runoff of this product will be reduced by avoiding applications when rainfall or irrigation is expected to occur within 48 hours. ” Potential for Contamination of C ompost With the current uncertainty that exists regarding the potential for adverse effects to non target plants exposed to compost containing residues of halauxifen - methyl , the EPA proposed the follo wing label restriction until additional compost studies are provided that can allow the Agency to definitively rule out this uncertainty: “Do not compost any plant material from the treated area . ” The inclusion of this language on the label is intended to prevent potential contamination of compost by restricting the use of plant material treated with halauxifen - methyl to be used as a compost input. Potential for Off - site T ransport via Spray Drift In order to minimize the risks of spray drift, language is included on the label that is intended to reduce off - site transport, thereby reducing the potential for exposure to non - target plants . This includes; minimum droplet size restrictions of coarse and above (VMD ≥ 340 microns according to ASABE S572.1), use of low - dr ift nozzles, application pressures less than 30 psi, maximum wind speed restriction of 1 5 mph during application, and extensive Spray Drift Ma nagement language .Page 9 of 10 Uncertainty in Potential Synergistic Effects related to Tank - mixes A common agricultural practice involves tank mixing of pesticides, resulting in the co occurrence of multiple chemical stressors to target pests . The practice of tank mixing can result in significant economic benefits to the grower by allowing control of a wider variety of pests in a single application without incurring the expense of sequential applications. Additionally, by reducing the number of visits to the agricultural field, the g rower is also reducing fossil fuel use and emissions from large agricult ural equipment, as well as the potential exposure to pesticides that can result from multiple visits to the same area being treated. It is also widely accepted that t he practice of mixing products with different modes of action is essential to the managem ent of weed resistance. Because weed resistance is known to have a very costly impact to overall crop yields, which in turn negatively impacts growers’ harvests and the price of commo dities to the consumer, tools that aid in the prevention of resistance are considered to be a very important benefit to agriculture. Recently , in some cases, chemical companies have made claims that certain combined mixture s el icit enhanced activity or synergistic effects , meaning that when the chemicals interact, the overall effect is greater than the sum of the individual effects of each chemical . In EPA’s risk assessments for non - target plants , the Agency uses GLP guideline studies to determine poten tial toxicity to plants , involving endpoints such as biomass and reproductive health. EPA believes this approach is very reliable for these purposes. The proposed registration for halauxifen - methyl includes the EPA’s evaluation of vegetative vigor studies on the combination product, QuelexTM, containing both halauxifen - methyl and florasulam. These studies showed no synergistic toxicity to non - target pl ants, therefore EPA concluded that there is no synergy between halauxifen - methyl and florasulam. However, if there is evidence to suggest that there are potential synergistic effects with other combinations , EPA may require such data since the current dat abase for the individual chemicals may not provide adequate information on the risk to non - target organisms from such combinations. A t this time, the topic of synergy and multiple stressors is an uncertainty in assessing risk with tank - mix combinations . EPA must weigh this uncertainty against the benefits of applying tank mixes when considering a regulatory decision. Therefore, EPA is considering whether restrictions on tank - mixing are necessary to prevent unreasonable adverse effects , and is inviting comment s on the issue of synergism and the potential for tank mix restrictions, which will be taken into further consideration for the final risk - benefit analysis of halauxifen - methyl. International Harmonization Maximum Residue Limits ( MRLs ) have not been established by Codex for halauxifen - methyl on the commodities affected by this action. Proposed Regulatory Decision In cooperation with our regulatory partners in Australia and Canada, and considering the assessed risk to human health and the env ironment, the A gency concludes that halauxifen - methyl meets the regulatory standard under FIFRA. The Agency is proposing that, in light of thePage 10 of 10 approaches described above, the risks , including to non - target plants , are not unreasonable when considered in conjunction with the benefits of no risks of concern to human health and the addition of a chemical class that can help to minimize herbicide resistance. New data requirements for pollinators are being required as a condition of registration for halauxifen methyl . Therefore, the EPA is proposing to grant a conditional registration of halauxifen - methyl under Section 3(c)( 7 ) (c) of FIFRA. The A gency is proposing to register the following three products: XDE - 729 Methyl Technical • 95.9 % halauxifen - methyl • Only for formulation into a herbicide for use on actively growing wheat, barley and

triticale GF - 2685 • 10. 4% halauxifen - methyl • Only for use on actively growing wheat, barley and triticale GF - 2686 (Quelex TM ) • 10.4 % halauxifen - methyl • 10 .0 % florasulam • Only for use on actively growing wheat, barley and triticale