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the buffer zone to create an offsite exposure. Further, most fields have at least a 15-20 

foot-wide access road on all edges; and all but one soil use pattern will utilize tarps. Farm 

roads surrounding fields make a de facto barrier to vegetation along the perimeter of the 

treated fields. It is not realistic to assume that methyl bromide will travel in the soil >5 

feet away from the injection site, let alone the 15-20 feet of hard-packed soil found under 

farm roads. 

Furthermore, essentially all soil applications used today require tarps to limit the amount 

of methyl bromide that can escape the soil. Only one, very limited, use site does not 

require tarps: orchard replant. However, these applications are deep injected, either using 

deep-shank or deep-probe, which limit the ability of methyl bromide to volatize from the 

field and move laterally within the soil. Moreover, the amount of methyl bromide used in 

this singular non-tarped use pattern has dwindled. Methyl bromide was used via the nontarped deep-shank method on less than 100 acres of orchard replant land in California in 

the last two years (2012- 2013) combined. 

EFED Response: 

Based on evaluation of comments regarding the deep injection requirements for orchard 

use, EFED agrees the danger to potential adjacent crops may be minimal from lateral 

transport through soils. EFED recently confirmed with the Biological Economics 

Assessment Division that the untarped methyl bromide use is small, and that exposure 

scenarios with methyl bromide translocation via runoff would be limited. In addition, 

EFED agrees that exposure due to diffusion alone will not likely occur over large enough 

distances from the treated field to impact non-target plant seeds off the treated field. 

Though road beds may often be located around application sites, this may not always be 

the case, but this factor does not effect our assessment. The required buffer zone of 25 ft 

or more is related to worker and bystander entry restrictions and would also not factor 

into our assessment. 

EFED will not conduct an assessment including exposure to plant seeds off of the 

treated field. Consequently, EFED will recommend removal of the seedling 

emergence data requirement from the Data Call-In Notice for registration review. 

 

(2) MBIP Comment: Regarding Vegetative Vigor Study Requirement 

Our initial review suggests that the most likely protocol would mirror the non-guideline 

protocol developed and approved by EPA for the Vegetative Vigor study required in the 

prior Data Call In to meet Guideline 850.4150. (MRID No. 49171601). Therefore, it is 

unclear what new data, if any, a second replication of essentially the same protocol would 

provide. 

EFED Response: 

EFED acknowledges the receipt of the study (MRID No. 49171601). We have included 

it in the DCI since it was received recently. The study is currently under review. Given 
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the late submittal of the study, EFED will recommend it remains on the DCI. However, 

this study may be used to fulfill the vegetative vigor data requirement contingent upon 

the determination of its acceptability for use in risk assessment. 

(3) MBIP Comment: Regarding Environmental Chemistry Methods/Independent 

Laboratory Validation Study Requirement

An Environmental Chemistry Methods (ECM) was submitted to EPA as part of 

MRID No. 48006001. 

EFED Response: 

The ECM report cited by MBIP is included in Appendix H of the field volatility 

guideline study report, “Monitoring of Methyl Bromide and Chloropicrin Field Emissions 

From Shank Applications at Shallow and Deep Injection Depths”, (MRID No. 

48006001). The citation provided by MBIP appears to be an abbreviated report of the 

laboratory analytical method used in the field volatility study air concentration 

measurements for methyl bromide. In order to fulfill this study requirement, a complete 

study report of this method as specified under the Standard Evaluation Procedure (SEP) 

in Guideline No. 850.6100 is needed. Furthermore, an independent laboratory validation 

of this method performed by a separate study director is required to fulfill this study. 

Please refer to the, “Group F – Field Test Data Reporting Guidelines”, section of the 

website provided below which specifies the reporting requirements to support this study 

requirement: 

http://www.epa.gov/ocspp/pubs/frs/publications/Test_Guidelines/series850.htm