James L. Kunstman, Ph.D. 1. CERTIFIED MAIL RETURN RECEIPT REQUESTED

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1 James L. Kunstman, Ph.D. 1. New York State Department of Environmental Conservation Division of Solid and Hazardous Materials Bureau of Pesticides Management, 11th Floor 625 Broadway, Albany, New York Phone: (518) FAX: (518) Website: November 29, 2006 CERTIFIED MAIL RETURN RECEIPT REQUESTED James L. Kunstman, Ph.D. Director, Regulatory Services PBI/Gordon Corporation P.O. Box West 12th Street Kansas City, Missouri Dear Dr. Kunstman: Re: Registration of the New Active Ingredient Sulfentrazone Contained in the Pesticide Product Gordon s ProForm Surge Broadleaf Herbicide For Turf (EPA Reg. No ) The New York State Department of Environmental Conservation (Department) has completed a technical review of your application received May 10, 2006 in support of registration of the above-referenced pesticide product in New York State. Gordon s ProForm Surge Broadleaf Herbicide For Turf (EPA Reg. No ) contains the new active ingredient sulfentrazone (N-(2,4-dichloro-5-(4-(difluoromethyl)-4,5-dihydro-3-methyl-5-oxo- 1H-1,2,4-triazol-1-yl)phenyl) methanesulfonamide) (chemical code ). Gordon s ProForm Surge Broadleaf Herbicide for Turf is labeled for selective postemergence broadleaf weed control in turfgrass at institutional, ornamental, residential/domestic and agricultural (commercial sod production) sites. The product contains 0.67% (0.06 lb/gal) of the new active ingredient, sulfentrazone. The product also contains 18.79% dimethylamine salt of 2,4-D (1.4 lbs. acid equivalent (ae)/gal); 6.8% dimethylamine salt of mecoprop-p (0.50 lb. ae/gal); and 3.02% dimethylamine salt of dicamba (0.22 lb. ae/gal). These three active ingredients are components of products currently registered in New York State for uses similar to those of the Gordon s ProForm Surge product. The maximum seasonal application rate for Gordon s ProForm Surge Broadleaf Herbicide for Turf is lb. sulfentrazone/acre, 1.75 lbs. 2,4-D ae/acre, lb. mecoprop-p ae/acre and lb. dicamba ae/acre. Gordon s ProForm Surge Broadleaf Herbicide for Turf label states: For use by individuals/firms licensed or registered by the State to apply pesticide products. Therefore, Gordon s ProForm Surge Broadleaf Herbicide for Turf, under 6 NYCRR Part 326.2(g) would be classified as a Restricted Use Pesticide in New York State. The Department previously reviewed applications for the new active ingredient sulfentrazone, contained in Gordon s ProForm Surge Broadleaf Herbicide For Turf (EPA Reg. No ) (received March 31, 2005) and EH-1416 Herbicide (EPA Reg. No ) (received May 11, 2005). Environmental fate concerns regarding the potential of sulfentrazone

2 James L. Kunstman, Ph.D. 2. toleach into the groundwater resources of the State were identified. At that time, PBI/Gordon withdrew their product applications (see the Department letter dated February 13, 2006 at: To mitigate the potential effects on groundwater, PBI/Gordon submitted a new application for Gordon s ProForm Surge Broadleaf Herbicide For Turf (EPA Reg. No ), with amended labeling that: 1. Prohibits the sale, distribution or use of this product in Nassau or Suffolk Counties of New York State, and 2. Allows only one application per year in New York State. The product is labeled for use only by licensed or registered applicators via broadcast or spot application to warm-season and cool-season turfgrass in institutional, ornamental, residential/domestic and agricultural (commercial sod production) sites. The single application rate is listed as 3_ to 4 pints product per acre with a maximum of 5 pints per acre for control of tough perennial weeds in industrial or low maintenance areas. Based on the amended labeling submitted, the maximum application rate of sulfentrazone is lb ai/a/year. HEALTH EFFECTS RISK ASSESSMENT: Based on the original March 31, 2005 submission, the New York State Department of Health (DOH) completed a Human Health Effects Risk Assessment. Gordon s ProForm Surge Broadleaf Herbicide for Turf (EPA Reg. No ) contains the new active ingredient sulfentrazone and is labeled for selective post-emergence broadleaf weed control in turfgrass at institutional, ornamental, residential/domestic and agricultural (commercial sod production) sites. Gordon s ProForm Surge Broadleaf Herbicide for Turf also contains the active ingredients 2,4-D dimethylamine salt, mecoprop-p dimethylamine salt, and dicamba dimethylamine salt which are components of products previously registered in New York State for uses similar to those of the Gordon s ProForm Surge product. To satisfy the federal requirement for acute toxicity studies (except for the eye irritation study) on the Gordon s ProForm Surge product, the registrant submitted data on EH-1405 Herbicide (EPA Reg. No ). This latter product is a reasonable surrogate for the Gordon s ProForm Surge product since it contains the same active ingredients and at higher percentages, but is otherwise very similar in composition. On an acute basis, EH-1405 Herbicide was not very toxic to laboratory animals by either the oral, dermal or inhalation routes of exposure. This formulated product was not very irritating to rabbit skin and did not cause dermal sensitization (tested on guinea pigs). The Gordon s ProForm Surge product, which was tested for eye irritation only, was found to be severely irritating to the eyes (tested on rabbits). The DOH previously reviewed the active ingredient sulfentrazone in conjunction with the registration application for the pesticide product Spartan 4F Herbicide ( In that registration review, it was noted that sulfentrazone was not very acutely toxic to laboratory animals via the oral, dermal or inhalation routes of exposure. Also, this active ingredient was not very irritating to animal skin or eyes, and it was not a skin sensitizer. Sulfentrazone did not cause oncogenic or genotoxic effects. However, data from chronic and developmental/reproductive studies showed that this chemical

3 James L. Kunstman, Ph.D. 3. has the potential to cause some toxicity. The United States Environmental Protection Agency (USEPA) Office of Pesticide Programs established an oral reference dose (RfD) of 0.14 milligrams per kilogram body weight per day (mg/kg/day) based on a no-observed-effect level of 14 mg/kg/day from a rat multigeneration reproduction study (decreased body weight and body weight gain, testicular damage and increased gestation length). The USEPA conducted a risk assessment for dermal and inhalation exposure of workers to sulfentrazone from its use on turfgrass, including golf courses. For mixers/loaders/applicators, the margins of exposure (MOEs) for dermal and inhalation exposures were estimated to be 91,000 and 187,000, respectively. For these estimates, it was assumed that workers wore longsleeved shirt, long pants, shoes and socks and gloves (the Gordon s ProForm Surge Broadleaf Herbicide for Turf label requires the use of this personal protective equipment). For postapplication exposure of golfers to golf course turf treated with sulfentrazone, the MOEs ranged from 1,200,000 to 2,000,000, whereas for post-application exposures to sulfentrazone-treated residential lawns, the estimated MOE for dermal exposure of adults was 12,000 and for children, estimated MOE for dermal and incidental ingestion exposure combined was 6,000. Generally, the USEPA considers MOEs of 100-fold or greater to provide adequate protection for workers and the general public. There are no chemical-specific federal or New York State drinking water/groundwater standards for sulfentrazone. Based on its chemical structure, this compound falls under the 50 microgram per liter New York State drinking water standard for unspecified organic contaminants (10 NYCRR Part 5, Public Water Systems). In the previous review of sulfentrazone, the DOH noted that sulfentrazone appears to have a high mobility through some soil types and thus has the potential to contaminate groundwater and drinking water. The available information on sulfentrazone and Gordon s ProForm Surge Broadleaf Herbicide for Turf (using EH-1405 Herbicide as a surrogate) indicates that neither the active ingredient nor the formulated product was very acutely toxic, irritating to the skin or a sensitizer in laboratory animal studies. Furthermore, sulfentrazone was not carcinogenic in rats or mice. The Gordon s ProForm Surge product, however, has severe eye irritating properties. To mitigate these adverse effects to the eye, the product label has the precautionary statement: Corrosive. Causes irreversible eye damage. In addition, the label requires that applicators and other handlers must wear protective eyewear. Although data from developmental/reproductive and chronic studies showed that sulfentrazone has the potential to cause some toxicity, the estimated risks to workers from the use of the Gordon s ProForm Surge product or to the general public from post-application exposure to sulfentrazone are within the range that the USEPA generally considers acceptable. This chemical, however, appears to have the potential to leach through soil and contaminate groundwater/drinking water. Given the above, the DOH does not object to the registration of Gordon s ProForm Surge Broadleaf Herbicide for Turf when registered with the amended labeling bearing the New York State specific language. ECOLOGICAL EFFECTS RISK ASSESSMENT: Based upon an initial screening, the Department s Division of Fish, Wildlife & Marine Resources, Bureau of Habitat has no objection to the registration of Gordon s ProForm Surge Broadleaf Herbicide For Turf. However, a complete ecological effects risk assessment was not completed for this product.

4 James L. Kunstman, Ph.D. 4. ENVIRONMENTAL FATE RISK ASSESSMENT: Based on the original March 31, 2005 submission, the Department s groundwater staff completed an Environmental Fate Risk Assessment. Solubility: Sulfentrazone has a solubility of 780 mg/l. Hydrolysis: According to the June 16, 2003 EFED memorandum for Section 3 Registration, sulfentrazone is not susceptible to hydrolysis with half-lives of 143 days at ph 5; 207 to 375 days at ph 7; and 348 days at ph 9 in sterile buffered solutions. Aqueous Photolysis: In an acceptable study (MRID ), sulfentrazone photodegraded with a half-life of 12 hours in ph 5, one hour in ph 7 and one hour in ph 9 sterile buffer solutions. Major degradates were found at ph 7; des-dichloromonohydroxy sulfentrazone at 12.8%; 2,4-dihydroxy sulfentrazone at 11.7%. Methyl triazole was the major degradation product, reaching 25.7% of the applied at the end of ten days exposure. Soil Photolysis: According to the June 16, 2003 EFED memorandum for Section 3 Registration, sulfentrazone is very stable to photolysis on sand and sandy loam soils with halflives of 98 and 161 days, respectively. Aerobic Soil Metabolism: In an acceptable study (MRID ), sulfentrazone degraded with a half-life of 535 to 555 days in a sandy loam soil (1.6% OM and ph 6.7) and 534 to 541 days in a silty clay loam soil (4.2% OM and ph 6.6). One major degradate was found, F carboxylic acid at 10.8%. Anaerobic Aquatic Metabolism: In an acceptable study (MRID ), sulfentrazone degraded very slowly in a flooded loamy sand sediment with an estimated half-life of nine years. Adsorption/Desorption: In a partially acceptable study (MRID ), the Data Evaluation Record (DER) report states that radiolabeled sulfentrazone was mobile in columns of sandy loam. Two degradates were found, both minor, but the USEPA indicated that they were very mobile. They were 3-hydroxymethyl F6285 and 3-carboxylic acid F6285. This study was scientifically sound but did not meet Subdivision N Guidelines (MRID ). Soil Type %OM ph K oc adsorption K oc desorption sandy loam silt loam silty clay loam sand Terrestrial Field Dissipation: In an acceptable study (MRID ), sulfentrazone dissipated in the 0 to six-inch layer of a bare ground clay loam soil with a half-life of one year. Sulfentrazone was detected in the six- to 12-inch soil layer at four to nine ppb at 61 through 451 days and 20 ppb at 531 days. At all sampling intervals, sulfentrazone averaged <4 ppb in soil at depths below 12 inches. Degradate 3-carboxylic acid F6285 averaged <11 ppb in the 0 to sixinch depth and <2 ppb below the six-inch depth at all sampling intervals.

5 James L. Kunstman, Ph.D. 5. In an acceptable study (MRID ), sulfentrazone dissipated in the 0 to six-inch layer of a bareground clay loam soil with a half-life of 1.5 years. Sulfentrazone was detected in the 0 to six-inch soil layer at 67 to 95 ppb at 453 to 554 days. Trace amounts (<3 ppb) were detected at the six- to 12-inch depth. Degradate 3-carboxylic acid F6285 ranged between three to 13 ppb in the 0 to six-inch depth in all soil samples collected between day three and day 554. In an acceptable study (MRID ), sulfentrazone dissipated with an estimated half-life of 121 days in the entire 48-inch soil column of a plot of loamy sand soil. Sulfentrazone was detected in the 0 to six-inch soil layer at 13.4 to 22 ppb at 103 to 368 days. Sulfentrazone was detected in the soil to a depth of 48 inches, with maximum average concentrations of 36.7 ppb in the six- to 12-inch depth, 10.9 ppb in the 12- to 18-inch depth, 6.6 ppb in the 18- to 24- inch depth, 5.2 ppb in the 24- to 30-inch depth, 10.8 ppb in the 30- to 36-inch depth, three ppb in the 36- to 42-inch depth, and one ppb in the 42- to 48-inch depth. Degradate 3-carboxylic acid F6285 ranged between <11.5 ppb in soil from the 0 to six-inch depth and <7.3 in soil collected from depths below six inches at all sampling intervals. Prospective Small-Scale Groundwater Study: According to the information presented, three prospective groundwater monitoring studies are currently being conducted at three sites. These studies were required based on the original registration for soybeans. Selection of the three sites was to represent the 75 th, 85 th and 95 th percentile vulnerability of groundwater in the projected use area. A single small-scale prospective groundwater monitoring study was previously conducted prior to the conditional USEPA registration of sulfentrazone, and, in spite of having to be terminated early because of an irrigation accident, confirmed the leaching of sulfentrazone and its acid derivative to groundwater. Preliminary results from the three groundwater studies suggest that sulfentrazone and the acid degradate are very mobile. USEPA Comments: A March 22, 1996 Environmental Fate & Ground Water Branch memorandum states: No decision has been made at this time regarding what additional measures might be necessary to mitigate any potential for sulfentrazone use to contaminate groundwater. Recommendations will be made upon completion of the Agency s review of the final report for the small-scale prospective groundwater monitoring study submitted by the registrant. Modeling: The Department s groundwater model (LEACHP) using Riverhead soil, a K oc of 29, a half-life of 535 days, and the maximum application rate of lb ai/acre/year, predicts breakthrough in four months and cyclical sulfentrazone concentrations ranging from five to 22 ppb over the ten-year modeling cycle. LEACHP simulation using Howard soil, a K oc of 40, a half-life of 534 days, and an application rate of lb ai/acre/year, predicts breakthrough in year two and sulfentrazone concentrations ranging from seven to 13 ppb in years three to ten of the ten-year modeling cycle. Note that the application rate used in this simulation is less than the maximum application rate (0.074 pounds per acre per season) on the Gordon s ProForm Surge Broadleaf Herbicide For Turf label.

6 James L. Kunstman, Ph.D. 6. Given sulfentrazone s long half-life, very low K ocs, and LEACHP modeling projections, it appears that use of Gordon s ProForm Surge Broadleaf Herbicide For Turf as originally labeled will have a negative impact on water quality in New York State. To mitigate the potential groundwater concerns, PBI/Gordon Corporation provided a product label that: 1. Prohibits the sale, distribution or use of this product in Nassau or Suffolk Counties of New York State, and 2. Allows only one application per year in New York State (0.037 lb ai/a/yr). Also, to ensure that this product will be used in strict accordance with label directions, the product is classified as restricted use in New York State in accordance with 6 NYCRR Part (e). Additionally, with cooperation of the Department, PBI/Gordon Corporation is conducting a groundwater study on Long Island to further define the leaching characteristics on turf. Assuming a 50% uptake by turf, the new effective application rate for sulfentrazone is lb ai/a/yr. Modeling on Riverhead soil using a K oc of 71 and a half-life of 555 days, projected cyclical peaks range from between about 1.8 to 2.6 ppb. Modeling on Riverhead soil using a K oc of 615, and a half-life of 535 days, projected breakthrough in year 1, and slowly increasing levels up to about 0.12 ppb. Environmental fate data suggest that sulfentrazone has the potential to leach through soil and contaminate groundwater/drinking water under certain conditions. Computer modeling predicts low-level leaching to groundwater in vulnerable aquifers. However, classification as a restricted use product, limiting the use to upstate NY, and allowing only one application per year indicates that there is minimal risk to the environment. REGISTRATION ACTION: The Department hereby accepts Gordon s ProForm Surge Broadleaf Herbicide For Turf (EPA Reg. No ) for registration as a Restricted Use Pesticide product in New York State. Acceptable labeling bears the following text: Not for sale, distribution, or use in Nassau or Suffolk Counties in NY State. Additionally, in the Use Rates for Table 1 and Table 2, the label states: New York: Only one application per year of this product is allowed. This product is not allowed to be sold, distributed, or used in Nassau or Suffolk counties. Enclosed for your files are the Certificate of Pesticide Registration and New York State stamped ACCEPTED labeling. While it is not expected that labeled use of Gordon s ProForm Surge Broadleaf Herbicide For Turf will impact groundwater/drinking water, if sulfentrazone is detected in groundwater/drinking water in multiple locations, the Department will investigate and, if necessary, take appropriate steps to mitigate this and future contamination. The Department would expect to work closely with PBI/Gordon Corporation to investigate and mitigate this contamination. Possible actions (not inclusive) by the Department could range from

7 James L. Kunstman, Ph.D. 7. modification of label language, suspension of the registration, or refusal to renew the registration. Gordon s ProForm Surge Broadleaf Herbicide For Turf (EPA Reg. No ) is classified as a Restricted Use Pesticide in accordance with rules and regulations 6 NYCRR Part 326.2(g) and Part (e). As such, this product is restricted in its purchase, distribution, sale, use and possession in New York State. According to Department regulations specified in 6 NYCRR 326.3(a): It shall be unlawful for any person to distribute, sell, offer for sale, purchase for the purpose of resale, or possess for the purpose of resale, any restricted pesticide unless said person shall have applied for, and been issued a commercial permit. If you require information regarding a commercial permit, please contact the Pesticide Reporting and Certification Section, at (518) In addition, the Pesticide Reporting Law (PRL) requires all certified commercial pesticide applicators to report information annually to the Department regarding each pesticide application they make. Commercial pesticide retailers are required to report all sales of restricted pesticide products and sales of general use pesticide products to private applicators for use in agricultural crop production. If no sales are made within New York State, a report still must be filed with the Department indicating this is the case. Information relating to the PRL or annual report forms may be obtained at the Department s website at or by contacting the Pesticide Reporting and Certification Section, at (518) Please note that a proposal by PBI/Gordon Corporation or any other registrant to register a product containing sulfentrazone, whose labeled uses are likely to increase the potential for significant exposure to humans or impact to the environment, would constitute a major change in labeled (MCL) use pattern. An application for a MCL must be accompanied by a new application fee and meet the requirements specified in 6 NYCRR Part Please contact Samuel Jackling, Chief of our Pesticide Product Registration Section, at (518) , if you have any questions. Serafini Enclosure Sincerely, Maureen P Maureen P. Serafini Director Bureau of Pesticides Management cc: N. Kim/D. Luttinger, NYS Dept. of Health R. Zimmerman/R. Mungari, NYS Dept. of Ag. & Markets W. Smith, Cornell University, PSUR