Page 1 of 23 UNITED STATES ENVIRONMENTAL PROTECTION AGENCY WASHINGTON D. C., 20460 OFFICE OF PREVENTION, PESTICIDES AND TOXIC SUBSTANCES PC Codes: 012501, 012502, 013802, 013803, 013806 DP Barcode: D309099, D329699 Date: June 27, 2006 MEMORANDUM SUBJECT: RESPONSE TO PUBLIC COMMENTS. The Environmental Fate and Effects Division's Response to Comments on EPA's Phase 3 Reregistration Eligibility Decision Document for the Organic Arsenic Herbicides ( OPP Docket# OPP 2006 0201).

TO: Lance Wormell, Chemical Review Manager Reregistration Branch II Special Review and Reregistration Division ( 7508C)

FROM: Keara Moore, Chemist Environmental Risk Branch III Environmental Fate and Effects Division ( 7507C)

THROUGH: Mark Corbin, Senior Environmental Scientist Daniel Rider, Branch Chief Environmental Risk Branch III Environmental Fate and Effects Division ( 7505C)

The attached document titled, " EFED's Response to Comments on EPA's Phase 3 Reregistration Eligibility Decision Document for the Organic Arsenic Herbicides" was generated in the Phase 4 period of the Proposed Public Participation Process to address comments submitted to the Agency following the publication of the Agency's Phase 3 Reregistration Eligibility Decision ( RED) Document for the Organic Arsenic Herbicides in the Federal Register April 5, 2006. EFED's portion of this response addresses comments from The MAA Research Task Force which consists of APC Holdings Page 2 of 23 Company/ Drexel Chemical Company, KMG Bernuth, and Luxembourg Pamol, Inc.; The Florida Department of Agriculture and Consumer Services ( FDACS); and Florida Department of Environmental Protection. The attached document is EFED's response to those comments.

EFED's chapters in support of the Agency's Phase RED are the Drinking Water Assessment ( DP Barcode D309097) and an Ecological Risk Chapter ( DP Barcode D327974). Comments relevant to those documents are addressed in this response and no revisions have been made to the original document. Page 3 of 23 TABLE OF CONTENTS I. Introduction ................................................................................................................... 4 of 23 II. MAATF comments ...................................................................................................... 4 of 23 Comment IV A: Modeling Approach Comment IV B: Monitoring Data Comment V A: Percent Cropped Area for Turf Comment V B: Spot Treatment on Turf Comment VI: Use of Open Literature Studies Comment VII: Comparison to MCL and SSLs Comment XI: Ecological Risk Assessment III. FDACS comments..................................................................................................... 21 of 23 IV. FDEP comments ....................................................................................................... 23 of 23 Page 4 of 23 EFED'S RESPONSE TO COMMENTS FOR THE ORGANIC ARSENIC HERBICIDES I. Introduction The following is EFED's response to comments on the Phase 3 Reregistration Eligibility Document ( RED) for the organic arsenic herbicides, generated in response to the comments submitted to the public docket by the registrants and by departments of the State of Florida to the Agency following the publication of the preliminary risk assessment ( Phase 3) on the organic arsenic herbicides in the Federal Register April 5, 2006 to begin Phase 4 of the Public Participation Process. Some of the responses serve as clarification or a restatement of Agency policies and guidance and it is hoped that this will provide a greater understanding of the Agency's position and procedures on these matters. Comments concerning Agency assessment of the environmental fate and persistence of the organic arsenic herbicides, interpretation of available data, generation of drinking water estimates, and assessment of ecological risk were submitted. These comments are addressed individually below.

Comments addressing the availability/ efficacy of substitute pesticides, the toxicology of arsenicals, and the dietary and occupational/ residential exposure will be addressed in separate documents by the appropriate divisions: the Biological and Economics Assessment Division ( BEAD) and the Health Effects Division ( HED).

II. MAATF Comments IV   A. EPA should adopt a modeling approach that is consistent with actual data and real world processes.

OPP models the organic arsenicals reaching drinking water and arbitrarily assumes that they are totally converted to inorganic arsenic in the water. This conceptual approach does not account for the data demonstrating that transformation of organic arsenic to carcinogenic inorganic arsenic can occur only in the soil, and only to a very limited extent, and that only inorganic arsenic that is not bound to the soil can be transported to surface water. EPA should adopt a different modeling approach, one that is consistent with the actual data and real world processes and that focuses only on inorganic arsenic for cancer risk assessment. The cancer risk assessment should be based on the estimated concentrations of inorganic arsenic that could be produced in soil and then transported to water ( i. e., excluding the fraction that is bound to the soil). This is the only approach that is consistent with the data and with science. See Attachments 5 and 6.

( Please note: Some statements included in the referenced attachments are more relevant to other sections of these registrant comments and will be addressed in those sections: Comparison of modeling results with monitoring data, section IV B; use of a PCA for turf, section V A; use as a spot treatment on turf, section V B) Page 5 of 23 EFED answer: The registrant presents two primary objections to EFED's general aquatic modeling approach: that the modeling is not consistent with actual data and realworld processes and that it arbitrarily assumes total conversion of organic arsenicals to inorganic arsenic. These comments are directed at the approach used in modeling inorganic arsenic as a metabolite of applied MMA and DMA. In addition to commenting on the general conceptual modeling approach, the registrant comments on specific modeling inputs used in estimating exposure to MMA and DMA. These comments will be addressed individually below.

Conceptual model for estimating exposure to inorganic arsenic ( Attachment 5, p. 1) For assessing risk from pesticides with toxic metabolites when data are not robust enough to model parents and degradates separately, a typical approach is to estimate exposure to the total toxic residues, including in the estimate both the parent compounds and the toxic metabolites. When organic arsenicals are applied, the arsenic may change forms but is otherwise persistent, so this typical approach would involve modeling with no degradation in order to estimate exposure to total arsenic, the sum of all arsenical species present. In this case, however, refinement beyond the typical approach is required; because toxicity for each arsenic species needs to be assessed independently, exposure to each species must also be assessed independently. These individual exposures must be estimated in ways that are sufficiently conservative for each species. Because a conservative exposure estimate for a parent compound is likely to underestimate exposure to the metabolite and vice versa, separate approaches had to be used to estimate exposure to parents and to metabolites.

Limited data are available to describe the transformation of applied organic arsenicals to inorganic arsenic, a process which appears to be quite variable with variable environmental conditions. Without data to adequately define input parameters, direct modeling of exposure to inorganic arsenic as a metabolite was not an option. Instead, EFED assumed that the modeled estimates of exposure to applied parent compounds represented a reasonable upper bound on the total amount of arsenic that would reach surface water in any form. The modeled EDWCs for parent compounds were therefore also reported as the EDWCs for total arsenic, with the units converted from µ g a. i./ L to µ g arsenic/ L in order to be comparable to the relevant endpoints and regulatory limits. The variability of arsenicals' environmental fate and the lack of adequate data to describe all of the relevant processes make it impossible to define with certainty what portion of this total arsenic in surface water will be present as any individual arsenical species. Therefore, the risk assessment states that the total arsenic EDWC also represents the maximum potential concentration of inorganic arsenic. As acknowledged in the assessment, this conceptual approach " does not necessarily represent the actual physical process [ since] inorganic arsenic is likely formed through metabolism in the soil, rather than after reaching surface water." Despite this, this approach is expected to provide a reasonable estimate of the amount of inorganic arsenic that may reach surface water. The modeling accounts for binding to soil and other routes of dissipation.

This discussion of potential exposure to inorganic arsenic is not equivalent to assuming total conversion of organic arsenicals to inorganic arsenic, as stated by the registrant. Page 6 of 23 This estimated total arsenic value is presented as the maximum possible concentration of inorganic arsenic, with the likely extent of possible conversion characterized extensively based on available open literature reports and registrant submitted studies. Contrary to the registrant's assertion that this transformation occurs " only to a very limited extent," observed metabolism of MMA and DMA to inorganic arsenic in the laboratory has ranged from undetected after several years to more than 80% transformation in several months. To account for 100% conversion, maximum exposure to inorganic arsenic would have been estimated by modeling the applied herbicide as arsenic with no metabolism. Comparing the reported EDWCs to values calculated this way shows that the peak value represents 88% conversion while the cancer value represents 72% conversion, reasonable upper bounds given the range of conversion observed in the laboratory.

The registrant recommends an alternative modeling approach for assessing exposure to inorganic arsenic. The first step of their approach is to model exposure as if no metabolism occurs, in order to define the maximum amount of applied arsenic that might reach surface water in any form. The second step is to estimate the amount of arsenic that will be present as parent compound by running the model again, this time with potential metabolism accounted for. The difference between the modeled concentration of total arsenic with no metabolism and the concentration with parent compound only, the registrant suggests, would represent the maximum potential concentration of inorganic arsenic. To demonstrate this approach, the registrant models exposure to total arsenic from the turf use and subtracts the parent compound EDWC reported in OPP's assessment.

If it were possible to determine the precise amount of parent compound that would reach surface water, this suggested approach would provide useful results. The variability of arsenicals' environmental fate, though, as well as the limitations inherent in modeling, make precise determination impossible. Instead, in order to be protective in considering potential risks, OPP must make conservative estimates of potential exposure. A modeling approach that is conservative for the parent compound is likely to underestimate exposure to the metabolite, and so use of the conservatively modeled parent EDWC in this approach will lead to underestimation of the inorganic arsenic EDWC. The registrant's proposed modeling approach does not adequately describe how to assure that EDWCs for inorganic arsenic as a metabolite are sufficiently conservative. An appropriately conservative approach similar to that suggested by the registrant would start with estimating total arsenic exposure as described in their first step. To determine an upper bound on the amount of that arsenic that may be present in the inorganic form, instead of subtracting a conservative estimate of exposure to the parent compound, the percent conversion observed in laboratory studies could be applied to this total arsenic estimate. As discussed above, that approach shows that the Agency's EDWCs reasonably represents the potential for conversion to inorganic arsenic.

Biphase dissipation of MMA and DMA ( Attachment 5, p. 7) The registrant notes that OPP's modeling does not account for the biphasic nature of arsenicals' aerobic soil metabolism as observed in several studies. The biphasic nature of Page 7 of 23 arsenical metabolism is characterized in the risk assessment, but the Agency states that " because of the variability of sorption processes, there are insufficient data to allow for determination of two separate rates." Instead, metabolism is modeled as a first order process, a choice expected to be protective given the importance of chronic exposure to arsenicals because " a long term half life that is less accurate in representing the faster initial rate of metabolism   better portrays the overall transformation."

Based on the results of a single study, the registrant incorporates biphasic half lives into aquatic exposure modeling, finding 30 year mean annual concentrations of MMA on turf ranging from 69.1 ppb to 76.4 ppb, depending on various assumptions. Comparing these results to the value reported in the assessment, 74.6 ppb, supports OPP's assumption that modeling arsenical metabolism as a first order process is appropriately protective.

Half Life for DMA ( Attachment 5, p. 15) The registrant asked for more detail on how the DMA aerobic soil metabolism half life was determined. As stated in the document, the half life modeled is the upper 90% confidence limit on the mean of six values observed in four studies. These studies include three open literature studies with DMA applied directly and one registrant study for which the Agency estimated a half life for DMA based on its formation and decline following application of MMA. The StatMost statistical program was used to perform non linear regression on this data using the Levenberg Marquardt least squares method for curve fitting. The data was fit to equations for two first order processes in series, based on the simplifying assumption that metabolism occurred as two individual first order processes: MMA transforming to DMA followed by transformation to inorganic arsenic. The equations are shown below where A represents parent MMA, B represents DMA as a metabolite, and C represents inorganic arsenic as a metabolite.

Although there is uncertainty in this calculation, it still provided important information because it is based on the only DMA metabolism data available from a study conducted according to GLP standards and run for a full year. The half life calculated from the formation and decline data, approximately 240 days, was nearly the same as the upper bound half life determined from the three open literature studies, so inclusion of this value in calculating the upper bound half life did not change the overall result. Instead, it provided additional support that the half life estimated from the open literature studies was reasonable in spite of the uncertainty in those studies. Page 8 of 23 Modeling of DMA as a degradate ( Attachment 5, p. 16) The registrant argues that it is inappropriate to model exposure to DMA as a metabolite of MMA by simulating application of DMA on the same day as MMA despite the documented lag time to yield DMA from MMA. This uncertainty is acknowledged in the drinking water assessment, which states that " additional uncertainty results from modeling the DMA metabolite as if it were applied at the same time as the MMA parent. Metabolism to DMA is not a rapid transformation and so in fact, when present, the metabolite will appear at a later date dependent on the environmental conditions." Given the variability in rates of transformation of MMA to DMA and the slow time period over which it actually occurs, there would be uncertainty in any estimate of " application date" of DMA as a metabolite and EFED believes that the modeling approach used is reasonable given the limitations of the data.

The registrant also states that " it appears that, by applying the 35% transformed DMA on the same date as the maximum label rate of MMA, EFED applied total MMA at a rate that exceeds the label limit." Because it is impossible to define with certainty what portion of this total arsenic in surface water will be present as any individual arsenical species, EFED presents the estimated exposures of MMA as parent compound and DMA as a metabolite as " maximum potential concentrations for each species that are not additive to a total possible concentration" so this is not equivalent of modeling in excess of the maximum labeled rate.

IV   B. EPA should compare modeled arsenic drinking water concentrations to actual community surface water drinking supplies.

EPA should compare the modeled arsenic drinking water concentrations to arsenic concentrations measured in actual community surface water drinking supplies, all of which contain arsenic levels that are significantly lower than the arsenic MCL. Such a comparison will demonstrate that even when MSMA and possibly DMA are used in cotton growing states, the arsenic levels in drinking water in those states are considerably below the MCL. It is noteworthy, that the drinking water concentrations modeled by OPP reflect only the arsenic present due to organic arsenic herbicide use, whereas the actual drinking water contain arsenic compounds from the herbicides, if any, plus additional sources, including natural and anthropogenic. Thus, monitored arsenic concentrations should be higher, not lower than the modeled concentrations. Absent such a comparison and corresponding reduction in the modeled concentrations, the risk assessment is not scientifically, and hence legally, defensible.

In summary, the estimated drinking water concentrations were generated using an erroneous approach with overly conservative assumptions resulting in modeled results that do not reflect actual community surface water concentrations consumed by the U. S. population, as discussed in Attachments 2 and 5 to this letter. Even in the states that use the most MSMA, surface water drinking concentrations are well below the MCL for total arsenic. Moreover, comparing the arsenic drinking water concentrations from various states show that there is no correlation between the areas where methylated arsenic Page 9 of 23 herbicides are used and the levels of arsenic in water ( see Table 3 in Attachment 2). EPA must correct the modeling, which the data show are clearly erroneous to ensure a scientifically defensible risk assessment.

EFED answer: The registrant presents Community Water System ( CWS) arsenic data from 26 states, compiled by the Office of Water, and compares these values to the modeled surface water EDWCs from the arsenical risk assessment. For each individual water supply system within those states, the dataset includes a single multiple year mean arsenic concentration. Based on the 75th percentile of these means for each state, the registrant asserts that all of these water systems contain arsenic levels significantly lower than the MCL, that there is no correlation between arsenic levels and agricultural use of arsenicals, and that the modeling is therefore erroneous.

Comparison of monitoring values with modeling results can be useful but needs to be done with care. Modeling is intended to estimate 1 in 10 year peak and average exposures while monitoring is likely to underestimate exposures and the frequency of occurrence due to limited number of samples and extended time between sampling events. The table of monitoring data cited by the registrant provides important information about the amount of arsenic that may be found in treated drinking water reaching populations served by public water supplies with surface water sources. When comparing these results to modeled values, however, it is important to keep in mind the goals of the sampling, designed by individual CWS, and of the subsequent statistical data analysis, performed by the Office of Water, which are different than the goals of the modeling in this risk assessment. The sampling was conducted as compliance monitoring while the statistical analysis was carried out to identify long term trends in arsenic exposure. In support of these objectives, the methods used lead to results that are not directly relevant to EFED's objective of protecting water resources from the localized, temporal impacts of pesticide use.

The primary issue resulting from the different data objectives is that these CWS data are mostly for samples taken after water treatment, so they do not represent the amount of arsenic actually reaching water sources. The Agency has an interest in protecting source water as well as treated water and does not include treatment in its modeling. The modeled concentrations estimate the amount of arsenic in water prior to treatment and are therefore not directly comparable to the monitored concentrations.

Another important difference is that CWS sampling is not targeted to arsenical use areas or times. Even in states that are users of arsenicals, large numbers of CWS sampling sites are outside of arsenical use areas. This is shown for cotton in Figure 1 ( use of arsenicals on turf is not included in this map). Additionally, only a single value for each system   the mean over a period of 3 to 20 years   is included in the statistical analysis. Based on the sampling summary in the OW report, the number of samples included in the analysis averaged less than one sample per year for systems in most states. The data from Texas, cited by the registrant as evidence of a lack of correlation between use and exposure, can be considered as an example. Less than 50% of the CWS intakes in Texas are in counties Page 10 of 23 !( !( !(

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0 500 1,000 250 Miles 4 Legend !( CWS SW Intakes Cotton Acres 0 1  40000 40001  80000 80001  200000 200001  300000 Cotton Acres Relative to Community Water System ( CWS) Surface Water Intakes Figure 1. Cotton acres relative to Community Water Systems intakes.

where cotton is grown, and none of the intakes are in the counties with the most cotton acreage. The mean number of samples taken in Texas was 6.4 per system, taken over a period of 5 years.

The statistical analysis done on these data was designed to examine long term systemwide trends rather than the local, temporal kinds of effects that would be expected to occur from agricultural use of pesticides. These results are not intended to be representative of the impact of agricultural arsenical use. Even if this non targeted dataset of treated water were to include any samples with arsenic levels elevated by agricultural arsenical use, the inclusion in the analysis of so much data from non use areas, along with the averaging of samples widely spaced through time, would be expected to mask these impacts. These data cannot, therefore, be expected to demonstrate a correlation between aquatic arsenic levels and use of arsenicals.

The Florida data presented by the registrant, although presented in the same table as the other state data, is from a different source and any analysis of this data was conducted by the registrant, rather than by the Office of Water. These data are not appropriate for comparison with modeled estimates for the same reasons stated above for the Office of Water data. The issue of the relationship between sampling sites and usage locations is very important for this Florida data. The data presented are only from surface water Page 11 of 23 systems, which, according to FDACS, make up only 10% of Florida's public water supply. The issue of groundwater arsenic exposure will be discussed in more detail in the response to comments from FDACS. However, it is important to note that the ground water arsenic levels in the Florida dataset are considerably higher than the surface water levels. The 2003 dataset, for which the registrant reports surface water results, had ground water detections of arsenic up to 48 ppb, while in 2005, ground water levels as high as 240 ppb were measured. These maximum arsenic levels were measured at intakes near an apartment complex ( 2003) and near a group that sells sod commercially ( 2005), both potential users of arsenical herbicides.

In reference to the cited monitoring data from Bednar ( 2002), Swancar ( 1996), and DERM ( 2002), the registrant states that " the [ modeling] predictions are not corroborated by monitoring results." Specifically, the registrant argues that: 1) it is inappropriate to compare speciated measurements of inorganic arsenic or unspeciated measurements of total arsenic to modeled estimated concentrations of organic arsenicals, 2) Chronic modeled values should be compared to the average of monitoring data rather than the peak, and 3) the monitoring sites do not mimic the modeled index scenario. ( Attachment 5, p. 10)

EFED answer: The uncertainties associated with monitoring data, both in general and specific to the individual studies, are discussed in the drinking water assessment. Given the potential for transformation of applied organic arsenicals to inorganic arsenic, it is appropriate to include measurements of total arsenic and inorganic arsenic in a consideration of monitoring data. It is true that other sources of arsenic may be present in the monitored concentrations; this uncertainty is characterized.

Limited targeted surface water monitoring data are available. Even targeted sampling is likely to underestimate both acute exposures and the frequency of occurrence due to the limited number of samples and the extended time between sampling events. Modeling of aquatic exposure estimates daily concentrations over 30 years. Monitoring occurs much less frequently on a shorter time scale and can't be expected to capture the same exposure. Even with weekly or biweekly monitoring, as in the Bednar cotton monitoring study, this represents 24 samples over a single season. It is not appropriate to take a mean of these values to compare to the modeled chronic result, which is an annual average of daily estimated concentrations expected to occur only once every ten years. Page 12 of 23 V   A. The risk assessment should consider a realistic percent cropped area for turf.

EPA assumes in the risk assessment that 100% of a watershed consists of turf. This assumption does not reflect real world circumstances and is contrary to available data. The U. S. watershed with the highest percent of crop is covered with 87% cropped area. OPP cannot reasonably ignore these data and assume instead that 100% of the watershed is turf  a minor " crop." Assuming 100% percent crop area results in an assessment that is not scientifically defensible. Instead, OPP should use the data submitted by the Task Force ( see Attachments 5 and 7).

EFED answer: As the registrant states, aquatic exposure from the turf use is modeled in this assessment with the assumption that 100% of the watershed is treated turf, in accordance with EFED policy. As acknowledged in the document, " this is likely an overestimation of exposure but the extent of overestimation is undefined." The limited monitoring data available to characterize the overestimation are discussed in the assessment.

For agricultural crops, a percent cropped area factor ( PCA) is used to adjust modeled EDWCs to account for the portion of a drinking water watershed that contains fields planted with a specific crop. PCAs have been developed for only a few major agricultural crops to date, largely limited by availability of data at the required scale. A default value of 87% is used for all other agricultural crops. Based on land cover data for agricultural crops, this default value is not applicable to the turf use. At the present time, data are not available at the spatial scale needed to develop the non agricultural equivalent of a national PCA for turf uses. The methods used to develop the agricultural PCAs were reviewed by a SAP which found that these methods were unsatisfactory for use with minor crops. For major crops, PCAs are based on 8 digit HUC ( average size over 1000 square miles) and county based crop acreages. The SAP expressed concern that this scale of data would " result in biases with minor crops," stating that " most drinking water supplies are fed by smaller watersheds that may have different PCAs  The PCA factors one gets ( especially for minor crops) for 8 digit watersheds versus 11 or 14 digit watersheds could be very different." Difficulties associated with defining a PCA for minor agricultural crops are magnified for turf, which incorporates multiple poorly delineated uses, including golf courses, sod farms, residential lawns, parks, athletic fields, and highway rights of way, among others. Any submissions of data analyses for development of a nationally representative turf PCA that account for all turf uses and are based on data at the appropriate spatial scale will be considered by EFED.

Determination of PCAs requires data on a national scale in order to establish the maximum area within any watershed that might be expected to be treated with pesticide. These estimated exposures are not intended to represent typical values likley to have widespread occurrence nationally. Rather, the intent of assessment at this level is to provide high end estimates of the exposure that might result from maximum use in the most vulnerable settings. Further refinement would be required to estimate the exposure in areas where use might be less extensive or areas that have less vulnerable environmental conditions. Page 13 of 23 The registrant submitted two recommendations of PCAs to be used in adjusting EDWCs resulting from the turf use. While both recommendations are based on constructive approaches, neither includes sufficient consideration of all relevant turf areas at the necessary spatial scale. The approach presented in Attachment 5 primarily relies on 8 digit HUC data to estimate maximum golf course and sod farm area and the only support provided for the residential value is an analysis of data from a single county. No discussion is included of other turf uses and no recommendation is provided for how these values should be combined. The recommended PCA presented in Attachments 6 and 7 defines a maximum cropped area for all turf uses based on an assessment of land cover within watersheds in south central Florida. Although the suggested approach includes an assessment of all turf categories at the scale of a 16 digit HUC, there is insufficient justification that the watersheds selected for evaluation at this scale are representative of a national maximum. The watersheds are identified based on data for golf course and sod farm acreage only without consideration of residential and other turf uses.

Attachment 5 also advises use of a golf course adjustment factor ( GCAF) to modify modeled EDWCs. The GCAF is only applicable to golf courses and would not affect EDWCs for the general turf use. Even for the golf course use, application of the GCAF would not significantly change the EDWCs, as the only labeled restriction is that arsenicals cannot be applied to golf course greens, which are accounted for by the GCAF as only 3% of golf course area.

V   B. The risk assessment should consider that MSMA is used on turf mainly in a spot treatment application.

Most of MSMA's turf uses are for spot treatment. OPP assumes that 100% of the turf is treated with MSMA, arguing that spot treatment is not enforceable. In fact, the label was recently revised following information from users that this is the way the product is used. Assuming four annual broadcast applications is wrong and produces a misleading and inaccurate risk assessment that is not scientifically or legally defensible.

EFED answer: EFED recognizes that spot treatment is a common practice in applying MSMA to turf. Spot treatment is enforceable and can be accounted for in estimating exposure if it is included on the label in a quantifiable way. The discussion of surface water modeling in the Drinking Water Assessment includes the following discussion of the practice of spot treatment:

Turf EDWCs are also expected to be lower if arsenicals are applied as spot treatments rather than as broadcast sprays, which appears to be a common practice. There is a possibility that this will be included as a restriction on the labels for DSMA and MSMA. Spot treatments are applied to less area than broadcast sprays and so lead to lower exposure. If application rate or area is limited on the label by a quantifiable amount, the estimated concentrations will be reduced by a proportional Page 14 of 23 amount. For example, if treatment of arsenicals on all turf uses is limited to 50% of a field, the EDWCs will go down to one half of the original value.

It is important to keep in mind, however, that while this is true for surface water, spot treatment may have less of an effect on ground water concentrations as described in more detail in the response to Florida's groundwater concerns.

VI  A. The soil analysis ignores quality data in favor of flawed literature studies: EPA Must Correct Its Erroneous Assumption That There Is 100% Transformation of Organic Arsenic Herbicides to Inorganic Arsenic, to Reflect the Data That Show Only a Small Portion Has the Potential to Transform OPP cites two flawed and unreliable published papers that are in contrast to all acceptable guideline studies and other peer reviewed literature, and on the basis of those two papers, assumes that there is 100% transformation of organic arsenicals in soil  All of the substantial body of scientifically valid data demonstrates that no more than 20% of applied MMA would convert to inorganic arsenic in natural soils. That figure represents the worst case result among the available, soundly conducted studies. Application of the 20% figure reduces by 5 fold the estimated inorganic arsenic level in soil. An assessment that assumes 100% transformation in the face of these data is scientifically indefensible and legally invalid. ( Described further in Attachment 8.)

EFED answer: Before directly addressing specific concerns of the registrants regarding the quality of data used in this assessment, it is constructive to describe in general how data were considered, from both registrant submitted studies and the open literature. It is true that fate studies from the open literature are used in this environmental fate discussion to a greater extent than is typical for this type of assessment. There is a large body of research spanning several decades which highlights the complexity of the fate of arsenical species and the processes of dissipation, metabolism, and redistribution that may occur. It is essential to account for the variability in these processes and their observed sensitivity to environmental conditions. As will be discussed in more detail below, the set of registrant submitted GLP studies that meet EFED data quality requirements are insufficient for this purpose. The options, then, for conducting a fate assessment that is satisfactorily protective of human health are to either make conservative assumptions about the fate of applied pesticides or to take into account the available open literature reports, acknowledging the uncertainty in those data.

Given the breadth of the literature on this topic, it was not practical to conduct a complete literature review. Instead, the previous RED chapters ( DMA: D210451, D212449, D255226, 2000; MMA: D277223, 2001) were drawn on, with the group of studies considered in those documents used as the foundation for the current assessment. In addition to those studies, literature introduced by the registrants or other stakeholders has been considered along with any more recent research that has come to EFED's attention. Older studies were not revisited unless issues related to them were brought up specifically. EFED's general approach on the use of open literature in assessing arsenical Page 15 of 23 fate was laid out quite clearly in the previous REDs, which stated that " the registrant, through FIFRA GLP studies, presents an unresolved environmental fate profile for cacodylic acid" and which found that laboratory studies from the open literature were " contrasting with the new GLP lab studies, and [ were] more consistent with the global picture" of arsenical fate. Similar conclusions were drawn about available data for MMA fate. In the five years that passed between the time that statement was made and the release of the current RED, the registrants submitted a review of the environmental fate of MMA ( MRID 46565301) but have not otherwise taken the opportunity to conduct additional studies or to present alternative data demonstrating why the earlier RED's conclusions were inappropriate.

In this assessment, available open literature studies are primarily employed in qualitative characterization of arsenical fate, with the exception of several studies used to estimate modeling input parameters for aerobic soil metabolism in the absence of acceptable registrant data. It is not true that EFED assumes 100% transformation of organic arsenical herbicides to inorganic arsenic. As described in more detail in the response to section IV A, EFED assumed that modeled estimates of exposure to applied parent compounds represented a reasonable upper bound on the total amount of arsenic that would reach surface water in any form. It was impossible to define with certainty what portion of this total arsenic in surface water will be present as any individual arsenical species, and so the risk assessment states that the total arsenic EDWC also represents the maximum potential concentration of inorganic arsenic. Comparing these reported values to the results that would have been obtained had 100% transformation been assumed shows that the peak value and cancer value represent 88% and 72% conversion, respectively. The range of transformation seen in the open literature supports these values as reasonable high end estimates.

It is well established that common bacteria from the soil environment are capable of metabolizing organic arsenicals to inorganic forms of arsenic. There is, however, uncertainty associated with the extent to which this transformation may occur in the environment. The registrant's statement that a " substantial body of scientifically valid data demonstrates that no more than 20% of applied MMA would convert to inorganic arsenic in natural soils" is not supportable. Their comment identifies 5 registrant studies, including aerobic soil metabolism studies for DMA and MMA, aerobic aquatic studies for DMA and MMA, and an anaerobic aquatic study for MMA ( MRIDs 42616001, 44767601, 43036101, 43314801, and 44767602) as well as 3 open literature studies in support of their statement. Although aquatic metabolism studies can provide important information about the fate of applied arsenicals, transformation to inorganic arsenic is expected to occur primarily through soil metabolism. The MMA aerobic soil metabolism study ( MRID 44767601), which measures 19% transformation to inorganic arsenic after one year, is cited as a principal source in EFED's fate assessment. Identified by EFED as the only available GLP metabolism study conducted for a full year, data from this study are used in determining model input half lives for both MMA and metabolite DMA and also in characterizing the potential extent of transformation to inorganic arsenic. Despite this study's value, given the variability expected in the Page 16 of 23 environmental fate of arsenicals, a single study in a single soil cannot be identified as " definitive of the worst case behavior," as the study is described by the registrant.

The other 4 registrant studies cited in this comment show no transformation to inorganic arsenic, as demonstrated by the fact that no 14CO2 is evolved. While these studies demonstrate that there are conditions in which metabolism does not occur, no explanation for this result is provided in light of the well established evidence of the potential for metabolism, and there is no analysis to define what environmental factors contribute to these conditions. Since metabolism of organic arsenicals is a bacterial process, one possible factor could be non viable soils and sediments. The registrant points to measured MMA ( from applied DMA) or measured DMA ( from applied MMA) as evidence of these soils' viability. In most cases, though, the pattern of these detections led both the study author and the EFED reviewer to conclude that they are artifacts of the analysis rather than products of transformation. For applied DMA, this conclusion is supported by the lack of CO2 evolution, which, as the registrant points out elsewhere in this comment, would be expected if demethylation of DMA to MMA had occurred. Only one of these studies is conducted in a soil environment and in all of them, the soils and sediments tested may be non viable. These studies, then cannot be assumed to include an adequately representative set of environmental conditions and can not be interpreted as demonstrating that transformation to inorganic arsenic is not expected in most conditions.

The registrant's comment also includes a review of open literature laboratory studies, recommending three studies to be used quantitatively by EFED to " help establish the expected extent of organic arsenical transformation to inorganic arsenic." All three of these studies were included in the current assessment's characterization of the potential for transformtaion to inorganic arsenic ( Von Endt, 1968; Dickens and Hiltbold, 1967; Abdelghani, 1977) as were two additional studies which the registrant finds deficient and recommends against using ( Woolson et al, 1982; Gao and Burau, 1997). The uncertainty associated with all of these studies is acknowledged in the assessment, which notes that they are all non GLP, they were all conducted for less than one year, and many of them do not include time series data. As the registrant states, the data presented in open literature studies are not as complete as that required in registrant studies, so these studies can not be evaluated to the same standard as are registrant submissions. Despite the acknowledged uncertainties associated with these studies, they are sufficiently robust to raise doubts that the single acceptable registrant aerobic soil study is adequate to represent the behavior of arsenicals in all environmental conditions. Given the variability of arsenical environmental fate processes and the limited available set of registrant data, the results of open literature studies can provide a more thorough understanding of the fate of applied organic arsenic herbicides.

To summarize the open literature study results, Von Endt observed a maximum of 10% transformation from MMA to inorganic arsenic, although values were still rising at the end of 21 days. Dickens observed up to 5.5% transformation in unamended soils and 16% transformation in amended soils after 30 days incubation. Abdelghani measured up to 29% transformation after 49 days. ( The registrant includes the Abdelghani study in the group of < 20% transformation because " six of seven trials" had less than 20% Page 17 of 23 transformation. This is a misleading statement; in fact, four of the trials were conducted with pure cultures of individual microorganisms and so are not comparable to the other results.) All of these studies estimated transformation to inorganic arsenic based on 14CO2 evolution, the method defined by the registrant as " superior" to extraction methods. The registrant's " substantial body of scientifically valid data demonstrat[ ing] that no more than 20%" conversion may occur, then, consists of a single GLP aerobic soil study showing 19% conversion, an additional aerobic soil study and a group of aquatic metabolism studies that show no transformation in possibly non viable conditions, and 2 open literature studies conducted for 30 days or less showing up to 16% conversion, with a third open literature study showing up to 29% conversion.

Given this limited data set, it is statistically invalid to describe the two additional studies which show greater than 50% transformation as " outliers." In these studies, Woolson found up to 52% transformation to inorganic arsenic after 60 days based on 14CO2 evolution while Gao directly measured extracted inorganic arsenic of up to 80% of applied organic arsenic after 70 days. The registrant subjects these two " outliers" to a much higher level critical analysis than performed for their " recommended" studies. The comments regarding general quality control and data presentation issues in these two studies will not be addressed specifically. These issues do lead to uncertainty, as acknowledged in the assessment, but are generally applicable to all open literature studies " recommended" by the registrant as well as to these " outliers."

The more substantial comments regarding these studies will be addressed directly. Regarding the Woolson ( 1982) study, the registrant points out that a similar study by the same author was submitted to the EPA in 1991 as a GLP study but was rejected, and so the registrant questions the data quality standards applied in use of open literature in this assessment. As discussed above, older studies not included in the 2000 RED or introduced by the registrant were not re evaluated. Woolson ( 1982) is included in the 2000 RED and discussed by the registrant in their review of the environmental fate of MMA but the more recent submitted study by Woolson was not included in either of those documents so it was not revisited for the current assessment. The 1991 Woolson study mentioned here by the registrant was rejected because sample calculations were not provided to describe how values were corrected for recovery and because background arsenic was not accounted for. It's true that these same issues are also relevant to portions of Woolson ( 1982), but the current assessment's characterization of potential transformation to inorganic arsenic is based on Woolson's 14CO2 evolution data, to which these problems do not apply. The registrant argues that in this case, 14CO2 evolution may represent demethylation of DMA to MMA instead of complete demethylation to inorganic arsenic. As discussed in the environmental fate assessment, there is limited evidence that transformation of DMA to MMA can be a significant pathway, and additionally, no MMA was detected in these soils.

The registrant also submits specific comments regarding the quality of data cited from Gao ( 1997) which demonstrate significant transformation to inorganic arsenic. This study originally came to EFED's attention because it was submitted by the registrant, who described it as " a useful construct to assess the behavior of DMA [ which] Page 18 of 23 systematically examined the effects of arsenic form, arsenic concentration, soil moisture, and nutrient addition on the transformations of arsenic compounds in soil [ and] conclude that DMA is demethylated and arsenate is the main metabolite" ( MRID 48803001). Despite their previous support of this work, the registrant now finds it to be deficient and " incapable of determining the extent to which organic arsenicals transformed to inorganic arsenic in soil." The primary issue raised with this study is that results are presented as " percent mineralization," calculated based on the amount of recovered parent compound rather than on directly measured inorganic arsenic. While this is true for one table of data, all of the published figures showing mineralization are based on direct measurements of arsenic, as confirmed by personal communication with the author. Determining the percent mineralization based on these direct measurements rather than calculated based on the remaining parent compound still shows up to 80% conversion, based on the line plot in Gao's Figure 7. With a reported mean extraction recovery of 91% with a standard deviation of 9%, it is possible that this result does not measure all of the arsenic present in the soil.

In conclusion, while there is some uncertainty associated with the use of open literature data which are not evaluated to the same standard as registrant submissions, the open literature results are sufficiently robust to raise doubts that the single acceptable registrant aerobic soil study is adequate to represent the behavior of arsenicals in all environmental conditions. The Agency's estimation of exposure to parent arsenicals is modeled based on the measured properties of those species, with this estimated exposure also assumed to represent a reasonable upper bound on the total amount of arsenic that would reach surface water in any form. It is impossible to define with certainty what portion of this total arsenic in surface water will be present as any individual arsenical species and so the risk assessment states that the total arsenic EDWC also represents the maximum potential concentration of inorganic arsenic. The open literature studies are used to characterize the possible extent of transformation. The range of transformation observed in these studies supports the estimated values of exposure to inorganic arsenic as reasonable high end estimates.

The Task Force urges OPP to account for the clearly demonstrated biphasic transformation of organic arsenic herbicides to account for the clearly demonstrated biphasic transformation of organic arsenic herbicides to inorganic arsenic in its modeling [ and] to account for the fractions of MMA and DMA that become irreversibly bound to soil.

EFED answer: See section IV A for discussion of the biphasic transformation of inorganic arsenic. The modeled estimates of exposure to MMA and DMA use half lives estimated from open literature and registrant submitted studies. These half lives are based on measurement of recovered parent compound and so already account for any MMA or DMA that is irreversibly bound to soil and not recovered. Page 19 of 23 VI  B. The soil analysis ignores quality data in favor of flawed literature studies: EPA Must Correct Its Erroneous Assumption That Inorganic Arsenic in Soil Is Completely Bioavailable to Reflect the Data That Show Only a Fraction Is Bioavailable EFED answer: EFED estimates the potential buildup of total arsenic in soil following long term repeated use of organic arsenicals. No direct calculations of ecological risk are calculated based on these estimates of soil exposure so the bioavailability of arsenic in soil is not relevant. Instead, ecological risk from soil buildup is characterized generally by comparison to OSWER Eco SSLs, values which are developed to be compared directly to measured soil concentrations as a screening level tool for determining risk.

VII  A, OPP should not compare total arsenic concentrations in water to the VII   B. arsenic MCL, which is based on inorganic arsenic and should not apply soils screening levels based on inorganic arsenic.

EFED answer: The drinking water assessment estimates exposure to total arsenic and states that " the total arsenic EDWC can be compared to regulatory levels, all of which are defined by total arsenic. For drinking water, the Maximum Contaminant Level ( MCL) for total arsenic is 10 ppb and is based on concerns for long term exposure. As a conservative assumption, the entire estimated total arsenic EDWC may be present as inorganic arsenic."

The same is true for soil screening levels, which are regulated in terms of total arsenic. The potential for buildup of arsenicals in soil is estimated as total arsenic and is compared to the Eco SSL standards, also in terms of total arsenic.

The MCL was established by EPA's Office of Water and the Eco SSLs were established by EPA's Office of Solid Waste and Emergency Remediation. OPP believes it must coordinate with other offices within the Agency to better understand and anticipate the results that OPP's actions under FIFRA may have on the progress of other offices.

XI   A. The Risk Assessment uses an overly conservative default 35 day half life for organic arsenic herbicide residues on foliage used by animals as a food source.

OPP calculated environmental exposure concentrations for MSMA and DSMA using the unreasonable default assumption that the half life for both MSMA and DSMA on foliar surfaces is 35 days. This default value was derived from Willis and McDowell ( 1987), who tabulated half lives for many pesticides applied to many crops, but no data for MSMA or DSMA were included in the study. Out of 447 half lives reported, only two were greater than 35 days, demonstrating this to be an extreme value. The TTR study conducted to evaluate the amount of MSMA that can be transferred from turf to standard cloth material ( MRID# 44958901), however, showed that the half life of MSMA residue Page 20 of 23 on turf ranges from 0.7 days to 9.5 days. Sound risk assessment principles and the law both require that OPP apply MSMA specific data from the TTR study rather than its generic default assumptions.

EFED answer: The EFED uses the upper bound estimate from Willis and McDowell ( 1987) when other appropriate adequate chemical specific data are not available to account for potential persistence on avian and mammal food items. The transferable residue study cited by the registrants is not a study type approved for replacing the default foliar dissipation half life. Measurement of total residues, not transferable residues, is required to account for all pesticide that may remain embedded on foliage used by animals as a food source. Furthermore, foliar dissipation of total residues would need to be measured on a variety of food items, under a variety of environmental conditions.

XI   B. EPA inappropriately uses the highest single day EEC to calculate chronic hazard quotients.

OPP inappropriately uses the maximum single day EEC to evaluate chronic risk, even though the TREX model calculates the foliar residue concentration for each day of one year, and chronic effects arise from exposure that is substantially longer than a single day. EPA ecological risk assessment guidance notes that, " the arithmetic average exposure over the time period of toxicological significance is the appropriate statistic" 18 for evaluating exposure and hazards. Therefore, chronic risk quotients should be calculated using EECs that occur over a period of time that is appropriate for the receptor ( e. g., 30 days for organisms with a short lifecycle; 1 year for organisms with a long life cycle). Using the maximum single day EEC ignores the reality of how exposure occurs.

EFED answer: The endpoint for the chronic risk quotient is the lowest NOAEC from rat reproductive studies. The reproductive effects observed in these studies may result from a single exposure; long term exposure may not be necessary to elicit the observed effects. The EFED screening risk assessment uses the single day maximum estimated EEC as a conservative approach. The degree to which this exposure is conservative cannot be determined by the existing reproduction study. Page 21 of 23 III. FDACS Comments 1a. Despite the recognition of the persistence of arsenic in the organic arsenical herbicide assessment, the EPA does not provide a sufficiently long term quantitative environmental fate analysis for organic arsenical herbicides  The fate information used in the EPA risk assessments considers the fate of organic arsenical herbicides over an inadequate, relatively short duration on the order of only months, which in fact, a much longer period on the order of several years to decades should be considered to accurately assess the fate and risks from the use of these herbicides.

EFED concurs that arsenicals are persistent in the environment. In considering the environmental fate of arsenicals, EFED is limited to the available data which, as noted by Florida, are on the scale of several months to several years. EFED is not aware of any studies providing additional data on longer time scales of several years to decades, but will consider any studies that are submitted.

EFED's modeling inputs are derived from laboratory studies conducted over several months to a year. First order half lives derived from these data are calculated as the upper 90% confidence limit on the mean and are expected to be sufficiently conservative in representing the long term fate of arsenicals. Exposures are estimated based on 30 years of daily values generated by models using these conservative half lives. Further characterization of the environmental fate of arsenicals is provided based on field studies on the scale of one to several years.

1b. The EPA assessment recognizes that organic arsenical herbicides convert to inorganic arsenic over time under a wide range of environmental conditions  FDACS agrees with the Agency's conclusion that [ volatilization of organoarsines] seems to be an insignificant route of dissipation for both organic and inorganic forms of arsenic."

EFED concurs that transformation of organic arsenical herbicides to inorganic arsenic is likely to occur to some extent under a variety of environmental conditions and accounts for this transformation in this assessment. Volatilization is not considered as a major dissipation route.

2a. Although the EPA's Drinking Water Assessment recognizes that organic arsenical herbicides could pose a risk to groundwater quality " in highly vulnerable situations," the risk assessment provides no quantitative assessment on the potential acute or chronic health risks from ingesting organic arsenical herbicides or their metabolites from potable groundwater sources  Recognizing Florida's vulnerable conditions and the persistence of arsenic species, FDACS asks EPA to further evaluate the potential for exposure to arsenical herbicides via the groundwater pathway.

b. Many forces, both natural and anthropogenic, cause arsenicals to dislodge from soil and become remobilized in the environment. These forces may be sufficient to increase arsenic concentrations in groundwater by up to several orders of magnitude. Page 22 of 23 EFED agrees that in certain areas, use of organic arsenical herbicides could pose a risk to groundwater quality. The risk assessment concludes that " in most situations, organic arsenical pesticides should not contribute significantly to the already existing burden of arsenic in groundwater from all sources, natural and anthropogenic. In certain vulnerable circumstances in areas with low background arsenic, application of organic arsenicals may lead to an increase in groundwater total arsenic."

The conclusion that leaching is possible in certain vulnerable environments is based primarily on monitoring studies which detected elevated arsenic in groundwater beneath Florida golf courses. Florida is described as " an area of concern because of its very sandy soils and shallow water tables" with golf courses " particularly susceptible to leaching because they typically have well drained soils and are heavily irrigated." Similar environments, both within Florida and nationally, would be considered to be highly vulnerable; these include areas with shallow water tables, low background arsenic levels, and well drained soils to which arsenicals do not sorb strongly. Soil types in hydrologic groups A and B are expected to be more prone to leaching; in particular, soil properties promoting arsenical leaching include low clay content and low iron and aluminum contents. The assessment acknowledges that there are multiple factors that may affect arsenical mobility, noting that " phosphate is expected to strongly compete for binding sites" and that " remobilization of sorbed arsenic with changing environmental conditions is also possible."

Because of limitations in the available screening models, modeling was not conducted to estimate the potential for exposure to arsenicals in groundwater. Instead, EFED presented the available targeted monitoring data, with detections of up to 120 ppb arsenic in groundwater below golf courses. Based on these studies, which include monitoring studies cited in Florida's comment, EFED found a " trend of groundwater arsenic at Florida golf courses well above local background levels and in many cases exceeding the federal MCL. Although evidence of the source of arsenic [ was] generally not conclusive, pesticide application [ was found to be] a probable contributor to these levels, and in some cases, appears to be the likely source." An additional data set cited in registrant comments includes measurements of arsenic levels in Florida Community Water Systems. In groundwater intakes in the Florida public water supply, multiple detections of arsenic were found above typical background levels, with a number of the detections occurring in intakes near parks, golf courses, or residential areas, all potential users of arsenicals. The highest detected arsenic level in the data set, 240 ppb, was measured in an intake near a commercial sod operation. EFED agrees that a prospective ground water study in Florida would be very useful in defining the potential risks from leaching of applied organic arsenicals. If submitted, EFED will consider these results in assessing exposure to arsenicals in groundwater.

When considering how changes to the labeled use pattern may lead to adjustments of the estimated exposure, it is important to keep in mind the different ways in which surface water and ground water may be affected. For example, the Drinking Water Assesment acknowledges that spot treatment is a common practice for use of organic arsenicals on turf. If that practice is incorporated in the label in a quantifiable way, EFED states that Page 23 of 23 " the estimated concentrations will be reduced by a proportional amount." This is true for surface water but may have less of an impact on groundwater exposure. Unlike surface water, which can be impacted by runoff of pesticides from an entire watershed, leaching of pesticides to groundwater directly impacts the local area of application. Used as a spot treatment, the same amount of pesticide may reach groundwater in the treated area, but the occurrence of leaching would be less widespread. Spot treatment then, would not necessarily decrease estimated concentrations in groundwater but could cause exposures to be more localized.

IV. FDEP Comments Descriptions of studies in Florida on arsenic impacts to groundwater beneath golf courses in the [ RED] are adequate to show the basis for concern regarding organoarsenical use  we concur with the conclusion that, " Specific to arsenic, recent pesticide application data coupled to concentration trends, along with known historical uses, point to MSMA application as a likely source of groundwater arsenic at these golf courses."  Residential use of organoarsenical herbicides, and its impact on drinking water, is also a potential problem  Most of the discussion of problems with arsenic in soil and/ or groundwater from organoarsenical use in the risk assessment focuses on Florida golf courses. The clear impression from the risk assessment is that arsenic accumulation and groundwater contamination problems.

EFED answer: As stated in this comment, much of the discussion of groundwater contamination from the turf use of organic arsenicals is based on monitoring results at Florida golf courses. This is because the available monitoring data targeted to this use are from Florida sites. Similar environments, both within Florida and nationally, would be considered to be highly vulnerable and have the same risks of groundwater contamination, as discussed in more detail in the response to comments from FDACS.


[Federal Register Volume 85, Number 22 (Monday, February 3, 2020)]
[Notices]
[Page 5951]
[FR Doc No: 2020-01950]

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DEPARTMENT OF ENERGY

Federal Energy Regulatory Commission

[Docket No. ER20-792-000]

Oklahoma Wind, LLC; Supplemental Notice That Initial Market-Based
Rate Filing Includes Request for Blanket Section 204 Authorization

    This is a supplemental notice in the above-referenced proceeding of
Oklahoma Wind, LLC's application for market-based rate authority, with
an accompanying rate tariff, noting that such application includes a
request for blanket authorization, under 18 CFR part 34, of future
issuances of securities and assumptions of liability.
    Any person desiring to intervene or to protest should file with the
Federal Energy Regulatory Commission, 888 First Street NE, Washington,
DC 20426, in accordance with Rules 211 and 214 of the Commission's
Rules of Practice and Procedure (18 CFR 385.211 and 385.214). Anyone
filing a motion to intervene or protest must serve a copy of that
document on the Applicant.
    Notice is hereby given that the deadline for filing protests with
regard to the applicant's request for blanket authorization, under 18
CFR part 34, of future issuances of securities and assumptions of
liability, is February 18, 2020.
    The Commission encourages electronic submission of protests and
interventions in lieu of paper, using the FERC Online links at http://www.ferc.gov. To facilitate electronic service, persons with internet
access who will eFile a document and/or be listed as a contact for an
intervenor must create and validate an eRegistration account using the
eRegistration link. Select the eFiling link to log on and submit the
intervention or protests.
    Persons unable to file electronically should submit an original and
5 copies of the intervention or protest to the Federal Energy
Regulatory Commission, 888 First Street NE, Washington, DC 20426.
    The filings in the above-referenced proceeding are accessible in
the Commission's eLibrary system by clicking on the appropriate link in
the above list. They are also available for electronic review in the
Commission's Public Reference Room in Washington, DC. There is an
eSubscription link on the website that enables subscribers to receive
email notification when a document is added to a subscribed docket(s).
For assistance with any FERC Online service, please email
<EMAIL_ADDRESS>or call<PHONE_NUMBER> (toll free). For
TTY, call<PHONE_NUMBER>.

    Dated: January 28, 2020.
Kimberly D. Bose,
Secretary.
[FR Doc. 2020-01950 Filed 1-31-20; 8:45 am]
 BILLING CODE 6717-01-P


[Federal Register Volume 83, Number 68 (Monday, April 9, 2018)]
[Notices]
[Pages 15153-15154]
[FR Doc No: 2018-07154]

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DEPARTMENT OF HEALTH AND HUMAN SERVICES

Food and Drug Administration

[Docket No. FDA-2008-D-0610]

Agency Information Collection Activities; Submission for Office
of Management and Budget Review; Comment Request; Guidance for Industry
on Postmarketing Adverse Event Reporting for Medical Products and
Dietary Supplements During an Influenza Pandemic

AGENCY: Food and Drug Administration, HHS.

ACTION: Notice.

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SUMMARY: The Food and Drug Administration (FDA) is announcing that a
proposed collection of information has been submitted to the Office of
Management and Budget (OMB) for review and clearance under the
Paperwork Reduction Act of 1995.

DATES: Fax written comments on the collection of information by May 9,
2018.

ADDRESSES: To ensure that comments on the information collection are
received, OMB recommends that written comments be faxed to the Office
of Information and Regulatory Affairs, OMB, Attn: FDA Desk Officer,
Fax:<PHONE_NUMBER>, or emailed to [email protected]. All
comments should be identified with the OMB control number 0910-0701.
Also include the FDA docket number found in brackets in the heading of
this document.

FOR FURTHER INFORMATION CONTACT: Domini Bean, Office of Operations,
Food and Drug Administration, Three White Flint North, 10A-12M, 11601
Landsdown St., North Bethesda, MD 20852,<PHONE_NUMBER>,
[email protected].

SUPPLEMENTARY INFORMATION: In compliance with 44 U.S.C. 3507, FDA has
submitted the following proposed collection of information to OMB for
review and clearance.

Guidance for Industry on Postmarketing Adverse Event Reporting for
Medical Products and Dietary Supplements During an Influenza Pandemic

OMB Control Number 0910-0701--Extension

    This information collection supports the above captioned Agency
guidance. The guidance includes recommendations for planning,
notification, and documentation for firms that report postmarketing
adverse events. The guidance recommends that each firm's pandemic
influenza continuity of operations plan (COOP) include instructions for
reporting adverse events, including a plan for the submission of stored
reports that were not submitted within regulatory timeframes. The
guidance explains that firms that are unable to fulfill normal adverse
event reporting requirements during an influenza pandemic should: (1)
Maintain documentation of the conditions that prevent them from meeting
normal reporting requirements; (2) notify the appropriate FDA
organizational unit responsible for adverse event reporting compliance
when the conditions exist and when the reporting process is restored;
and (3) maintain records to identify what reports have been stored.
    Based on the number of manufacturers that would be covered by the
guidance, we estimate that approximately 5,000 firms will add the
following to their COOP: (1) Instructions for reporting adverse events
and (2) a plan for submitting stored reports that were not submitted
within regulatory timeframes. We estimate that each firm will take
approximately 50 hours to prepare the adverse event reporting plan for
its COOP.
    We estimate that approximately 500 firms will be unable to fulfill
normal adverse event reporting requirements because of conditions
caused by an influenza pandemic and that these firms will notify the
appropriate FDA organizational unit responsible for adverse event
reporting compliance when the conditions exist. Although we do not
anticipate such pandemic influenza conditions to occur every year, for
purposes of the PRA, we estimate that each of these firms will notify
FDA approximately once each year and that each notification will take
approximately 8 hours to prepare and submit.
    Concerning the recommendation in the guidance that firms unable to
fulfill normal adverse event reporting requirements maintain
documentation of the conditions that prevent them from meeting these
requirements and also maintain records to identify what adverse event
reports have been stored and when the reporting process is restored, we
estimate that approximately 500 firms will each need approximately 8
hours to maintain the documentation and that approximately 500 firms
will each need approximately 8 hours to maintain the records.
    In the Federal Register of October 31, 2017 (82 FR 50431) we
published a notice inviting public comment of the proposed collection
of information. Although one comment was received, it did not respond
to any of the four information collection topics solicited in the
notice under the PRA. We therefore made no changes to our estimate of
the burden for the information collection, which remains as follows:

                                                     Table 1--Estimated Annual Reporting Burden \1\
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                Number of
                         Type of reporting                              Number of      responses per     Total annual   Average  burden    Total hours
                                                                       respondents       respondent       responses       per response
--------------------------------------------------------------------------------------------------------------------------------------------------------
Notify FDA when normal reporting is not feasible...................             500                1              500                8            4,000
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ There are no capital costs or operating and maintenance costs associated with this collection of information.

                               Table 2--Estimated Annual Recordkeeping Burden \1\
----------------------------------------------------------------------------------------------------------------
                                                     Number of
     Type of recordkeeping          Number of       records per    Total annual      Hours per      Total hours
                                  recordkeepers    recordkeeper       records         record
----------------------------------------------------------------------------------------------------------------
Add adverse event reporting                5,000               1           5,000              50         250,000
 plan to COOP..................
Maintain documentation of                    500               1             500               8           4,000
 influenza pandemic conditions
 and resultant high absenteeism
Maintain records to identify                 500               1             500               8           4,000
 what reports have been stored
 and when the reporting process
 was restored..................
                                --------------------------------------------------------------------------------
    Total......................  ...............  ..............  ..............  ..............         258,000
----------------------------------------------------------------------------------------------------------------
\1\ There are no capital costs or operating and maintenance costs associated with this collection of
  information.

    Dated: April 3, 2018.
Leslie Kux,
Associate Commissioner for Policy.
[FR Doc. 2018-07154 Filed 4-6-18; 8:45 am]
 BILLING CODE 4164-01-P