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Exposure 		Modeling Public Meeting (EMPM) Information and Products

Minutes of the April 6, 2004 Exposure Modeling Public Meeting

Minutes of the April 6, 2004 Exposure Modeling Public Meeting

OPP Conference Room

Crystal Mall Building 2

Room 1126

On this Page

Attendees

Status of Old Action Items

Introduction

Brief Updates

Next Meeting

Actions

Attendees

Name	Association

Dirk Young	 	OPP/EFED

Betsy Behl	 	OPP/EFED

William Eckel	 	OPP/EFED

Ron Parker	 	OPP/EFED

Mark Corbin		OPP/EFED

Mohammed A. Ruhman		OPP/EFED

Jim Lin		OPP/EFED

R. David Jones		OPP/EFED

Steve Bradbury		OPP/EFED

Donna Randall		OPP/EFED

James Hetrick				OPP/EFED

Subijoy Dutta				OPP/EFED

Lucy Shanaman				OPP/EFED

Stephanie Syslo				OPP/EFED

Jim Wolf				OPP/EFED

Alex Clem				OPP/EFED

Dana Spatz				OPP/EFED

Faruque Khan				OPP/EFED

Thuy Nguyn				OPP/EFED

Larry Liu				OPP/EFED

Mah Shamim				OPP/EFED

Larry Burns				EPA ORD

Piyush Singh	 	DuPont

Mark Russell		Dupont

Katherine Carr		Monsanto

Mary Nett	 	WQC

Pat Havens	 	Dow

Russell Jones	 	Bayer

T. S. Ramanarayanan		Bayer

Paul Hendley	 	Syngenta

Wenlin Chen		Syngenta

Scott Jackson	 	BASF

Elise McCoy	 	FMC

Mark Cheplick	 	Waterborne Environmental

Amy Ritter		Waterborne Environmental

Cathleen Hapeman			USDA/ARS

Tamara Estes				Stone Environmental

Michael Winchell			Stone Environmental

Lajan Barnes				Environmental and Turf Services

Qingli Ma				Environmental and Turf Services

Vince Piccirillo				VJP Consulting

Kurt Rindfusz				ERG

Young No				Keller and Heckman

Rick Reiss				Sciences international

Brent Solomon				Valent

David Sullivan				Sullivan Environmental

Benjamin Smallwood			NRCS

Top of page

Status of Old Action Items

Michael will schedule progress reports on the EFED research programs at the next EMWG meeting - cover in July

EPA to put Gail's presentation (once rechecked by USGS) up on the website - DONE

EFED will ideally add Tier 2 GW needs and conceptual model to the agenda for the January meeting - see below - will be covered  in July

Don will circulate an Excel spreadsheet of combined databases when available - aiming for the end of month  (Don will circulate an Excel spreadsheet of combined databases when available - aiming for the end of month  ) - PH to remind Don again

Michael Barret still to circulate PGW database templates (last meeting) and, if appropriate, Michael will arrange for a discussion topic on this at the January EMWG - Jim to cover

Ron Parker to update FIFRA EMWG on progress of the FAO comparative model at the next meeting - Cover in July

A demonstration of the EFED database will be given if possible at the January meeting - to be given later today

Michael Barrett to add a discussion of the details of the kinetics policy to the agenda of the first FIFRA EMWG after management has approved the draft as well as circulating the proposal itself. - ACTION: Betsy to progress with Efate Tech team

EPA to review CARES and PLUS - add CARES as a standard topic for updates to future meetings - Beth is ISLI is now the conduit for the model - Jim to invite Beth to report back on CARES progress at a future meeting

Larry Burns to provide a summary of recent changes and version numbers and the system to access older versions. Larry Burns received a list of key versions from EFED and has prepared a web accessible set of programs and release notes for EXAMS and PRZM (3.12.1 and 3.12. Beta - back to Feb 1998 - recompiled to work under XP) and will go back further [versions 1.0 - 2.3, 3.0] (already on CEAM site).

There will be a presentation on USGS GW model evaluation program at the next EMWG meeting - Jack Barbash will make a presentation in July (see Jan 2004 minutes)

EXPRESS Coding issue to be resolved if possible so that the industry review of EXPRESS can be completed - see update

EFED review of PRZM-EXAMS scenarios to be discussed - later today

EFED to provide information on new PCA policy for minor crops as soon as feasible - presentation available on Web site

Mark Cheplick, Tammara Estes and Ron Parker to resolve issue of reported truncation bug in EXPRESS and report via list server. - under way

Top of page

Introduction

Jim Lin introduced the meeting and reviewed actions as shown above

As a reminder the FIFRA EMWG web site can be found at
http://www.epa.gov/oppefed1/models/water/emwg_top.htm

Top of page

Brief Updates

PRZM-EXAMS model/ EXPRESS

Larry reported on the versioning and is looking at volatilization and furrow irrigation routines.  He is examining EXPRESS performance issues and is looking at ways to improve speed of transfer.  Manual is available - comments will be available by April 9.  Then will need to QA PRZM in situ - completion of EXPRESS for general use needs to be discussed with management. ORD will follow up once internal EFED QA.  ACTION: Industry will hold review until EFED release the manual.  Issue of inclusion of volatilization was discussed  - the current scenarios do not have the necessary sand, silt and clay information (this is a scenario issue).  ACTION: Agreed that the volatilization feature should be turned on but an internal decision on whether to use a constant soil temperature should be adopted and reported at the next EMWG.

Standard Scenarios

Ron reported that there is a three-person group that is reviewing the public comment - three major responses under way.

Original authors are checking detailed comments on scenarios - 90% complete

Specific OP scenarios targeted at particular uses/sites and these are being separated out and will only be used on a case by case basis

EFED is discussing options for further stakeholder input on scenarios.

New scenarios are becoming available - clarification will be made soon.

Groundwater

Betsy Behl reported that OPP, USGS (Jack Barbash et al) and others are working together to evaluate seven models, HYDRUS 2D, PRZM, LeachM,  LeachP, RZWQM98, GLEAMS, BS2D being run with data from two PGW sites and several NAWQA sites.  This group will report back on progress to EMWG next time.  Differences are being seen but no information available presently - Mark Corbin and Jim Wolfe driving this and PMRA involved.  Also work to look at FEMVTF documentation and other literature. ACTION: Jack Barbash will attend the next meeting to discuss preliminary findings

Scientist to Scientist Drinking Water treatment Workshop

AWWA and many others attended this meeting and a disk with all presentation is available - ACTION: Jim Lin will put the presentations from the DW treatment workshop on the EMWG website.

ACS Soil Dissipation Meeting ACS Anaheim 2004-01-06

Mark Corbin reported back on this useful meeting that focussed on technical data, conceptual model - ACTION : PH to feed back the collection of presentations from the ACS TFSD meeting to Mark Corbin for inclusion on the web site

European Efforts

A second FOCUS Groundwater group has just started meeting.  FOCUS kinetics has one more meeting left and the original landscape and mitigation group is finalizing their report.  A second FOCUS landscape and mitigation group will start in 2005. ACTION: Russell Jones to mention EPA availability to attend Landscape and Mitigation 2 group (starts 2005) at upcoming EEASG meeting in Europe to formally obtain an invitation.

Summary of the Fumigant Emission Modeling System (FEMS) - Dave Sullivan

Covered chemigation, center-pivot irrigation and shank injection uses of metam-sodium.  Many problems as there are very infrequent use and the exposure is highly variable due to diurnal variation as well as infrequent use.  Sealing practices are important to mitigate problems - especially if we can keep peaks away from the night-time.  Probabilistic approaches work well here.  Key monitoring /modeling link for verification/validation/ground truthing is with ambient monitoring across 4 days using a 4 or 6 hour sampling period. {Note: Metam-sodium could be monitored via remote concentration sensing in real time - slice in 3D}

Data Log normally distributed, fitted to a cubic fit - modeled at 1.5 m.  FEMS model addresses Application rate/method, acres applied and field shape, up to six endpoint concentrations, selected probabilistic variables, meteorological region, # simulated years.  EPA and industry will be meeting shortly to discuss common protocols.

Questions:

 How much field work would be needed to capture this deterministically??  Approach was to capture the worst case (Bakersfield) and then (money and time permitting) move to heavy soils.  However, capturing variable wind will be tough to cover

 What was model averaging time?  4 hours but FEMS can produce hourly outputs.

How does sealing work?  Need to have a good water moisture level initially.  Critical to keep it moist or even to compact the soil - needs to select form a toolbox of options.

PRZM with new Subroutine of Adsorption /Desorption Kinetics - Wenlin Chen

Wenlin described the rapid and slow phases of adsorption kinetics that mirror the biphasic degradation often seen in metabolism studies.  This could be due to microbial incapacitation OR to increasing binding (decreasing releasibility).  He showed the conceptual model for a variable rate desorption system and an associated analytical solution.  From Jury, Wagenet, Chen publications.

Using a set of examples with degradation operating in aqueous only or aqueous plus solid phase he led to the solution adopted for implementing the approach in PRZM.  This solution uses an adsorption/desorption constant, fraction on the equilibrium sorption site, degradation rate constant for soil pore water and on solid phase where needed.

The new program fits well with various data sets.  This revised code is available from WEI for experimentation

Points to consider include

Need for more validation

 How to deal with generalizing rate constants since the kinetics will be soil specific.  Otherwise may be somewhat site specific

 Correlate sorption rate constant with Koc

 Site specific investigation

 Use of paired Kd and half lives for exposure assessments

Evidence for a single chemical (with soil pH dependency) was provided linking soil bulk degradation with non-kinetic Koc values showing a simple relationship.  The impact of the value of paired Kd and half lives was shown in an example where the used of lowest Kd and longest half life greatly over-predicted leaching but the use of paired values helped greatly.

Wenlin suggested some reasons why some compound (classes) might exhibit paired Koc and half life and some might not.

Questions:

 What impact will this have on runoff??  May increase runoff (at least in erosion component)

 How is chemical added?  Via soil solution and equilibrium sorption portions.

Example suggested a cropped plot and bare plot that gave similar results - why?  Mark Cheplick suggested that this was a PRZM feature and Wenlin responded that he did not run the data sets for the cropped and bare plots

 How does this differ from PEARL routine??  There is degradation in the soil fraction of the kinetic portion.

 In 0-6 in calibration example, why not just increase the KD?  This will delay the peak.  This strongly reflects recent literature

 Is conceptual model over-specified?? After discussion agreed that it would be worth looking at the potential for simplification.

 How do you get a decent estimate of the long term Kd??  We need a longer study.  All agreed.

 Correlation of half life should be with long term DESORPTION rate.  Needs caution to avoid artificial data.  Need to keep the different approaches separate

 This means we really need to get complementary datasets for the same soil in lab, field and adsorption studies.

ACTION: All to try to download the revised the PRZM model and try it out with their own datasets. Discuss at July Meeting

Feedback from the Probabilistic SAP meeting - Steve Bradbury, Donna Randall and Dirk Young

New material including the PowerPoint slides used at the SAP will be available soon from the Web site. ACTION: All to download and read relevant material

Steve relayed that a key issue in both terrestrial and aquatic areas lead from the conceptual model and could be broadly summarized as "what exposure estimation refinements belong at Tier 2 and at Tier 3".  Key issues were the readily availability of data (essential for Tier 2), addition of complexity to models (should be minimal), etc

SAP members raised the issues of improved mathematical approaches and do more convenient sensitivity analyses.  SAP felt the need for workshops and alpha and beta testing and how to disseminate instructions for the approach.

Another key topic is validation, evaluating, ground truthing and confidence building and what sort of empirical data could help achieve these goals.  This philosophical thinking helped greatly and indicates that very careful specifications are needed.

Next steps were also discussed.  Based on data that is submitted by registrants we are presently reaching the limits of Tier 2.  Therefore, a key question is how the academic and government research communities can help meet key longer term goals (e.g. USGS, EPA ORD, USDA, ARS).  For example, distribution of receiving water bodies by region.

Aquatic group focussed purely on exposure assessment.

Questions:

Seems like a one-way process??  Why can't the process be done more openly and involve panel types earlier??  History is SAP driver from 1996 via ARAMDG to ECOFRAM and external peer review.  Then EPA took this report and ran with it with occasional check in with SAP.  This is where EFED is at now.  However, in addition, things like development and testing of techniques and models will involve the whole scientific community.  This will be even more important with the Tier 3 PRA - where open research processes are essential.

Need to educate the risk managers on how to deal with Probabilistic risk assessment output? In some cases deterministic methods may be good enough but in others the Problem Formulation will show us that PRA is the technique needed.  Key issues are the need to do "good enough" assessments to address needs.  Education is needed on all aspects of risk assessment and effective action as the concepts evolve.

Will we see an analysis of the historical guidelines, conceptual models and approaches and protection goals and pull together a unified EFED approach

 Current tier 2 aquatic risk assessment IS probabilistic but we have only been using a single point.?

Did the presentation on the CA water bodies reflect the scenario specific modeling?  No there may have been some confusion here.

Need to be very specific in the PF on what biology and water body types need to be protected - different

What next?  Get panel report back.  Assumed no show stoppers - will then move to sensitivity analyses and revised models for alpha and beta testing and training etc.  May be a meeting with SAP sooner rather than later on next steps and links to ORD/OPP research goals.  There may currently be a mismatch between exposure efforts and aquatic effects side and what pathways are most sensible to follow for EFED and research partners.

EXAMS has variable volume components - should we expose this to user community? Yes. The code in the EXAMS model will be made available.

Introduction and Demonstration of EFED's Pesticide Database - Mah Shamim and Larry Liu

Mah provided an update on progress on the database that is nearly ready for public release on the Web - will be announced on the list when available.  There will be a mechanism put in place to handle comments and corrections.  Now in Oracle and currently limited to 188 compounds registered pesticides with data that has been reviewed by EFED and/or AD and is viewed as sound.  The entries have been QA/QC'd.  Some product chemistry and field dissipation data remains to be added to fill in the data gaps.  Focus has been to get the interface optimized.  Will re-evaluate the file room to find other chemicals that are not included.  The data will be the half lives reported in the DER.  Units are not yet expressed in SI units.  Exportable into Excel.

Basically the whole gamut of useful data is included.  About 200 more actives may need to be added.

Questions asked by NRCS regarding the processing of the data - the database does not include any manipulated information.  Larry Liu showed examples of queries. The question was asked as to how the public can get information that links the active ingredient with the associated trade names.

ACTION: Kathleen Hapeman will send new address of ARS database that will continue to be maintained presently - Done

http://www.arsusda.gov/acsl/services/ppdb

Top of page

Next Meeting

Next meeting options include July 13 or 14 or following week.  Jim Lin will send around a voting email and then circulate the final date ASAP.

Top of page

ACTIONS

Old Items Carried through

Michael will schedule progress reports on the EFED research programs at the next EMWG meeting - cover in July

Don will circulate an Excel spreadsheet of combined databases when available - aiming for the end of month  (Don will circulate an Excel spreadsheet of combined databases when available - aiming for the end of month  ) - PH to remind Don again - Done

Michael Barret still to circulate PGW database templates and, if appropriate, Michael will arrange for a discussion topic on this at the January EMWG - Jim to cover for July

Ron Parker to update FIFRA EMWG on progress of the FAO comparative model at the next meeting - Cover in July

Michael Barrett to add a discussion of the details of the kinetics policy to the agenda of the first FIFRA EMWG after management has approved the draft as well as circulating the proposal itself. - ACTION: Betsy to progress with Efate Tech team

EPA to review CARES and PLUS - add CARES as a standard topic for updates to future meetings - Beth is ISLI is now the conduit for the model - ACTION: Jim to invite Beth to report back on CARES progress at a future meeting

There will be a presentation on USGS GW model evaluation program at the next EMWG meeting, this will link with the old action item on Tier 2 GW needs and conceptual model  - Jack Barbash will make a presentation in July (see Jan 2004 minutes)

New Items

Industry will hold review of EXPRESS until EFED release the manual and report that key aspects of the final ORD revisions to the code are fixed

ORD and EFED to agree whether the volatilization feature should be turned on in PRZM/EXPRESS and EFED to make an internal decision on whether to use a constant soil temperature.  Decision to be communicated over list server or via reporting at the next EMWG.

Jim Lin will put the presentations from the DW treatment workshop on the EMWG website.

PH to feed back the collection of presentations from the ACS TFSD meeting to Mark Corbin for inclusion on the web site

Russell Jones to mention EPA availability to attend Landscape and Mitigation 2 group (starts 2005) at upcoming EEASG meeting in Europe to formally obtain an invitation.

All to try to download the revised PRZM model and try it out with their own datasets. Discuss at July Meeting

All to download and read relevant PowerPoint slides from Probabilistic SAP

Jim Lin will confirm date and place of next meeting

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[Federal Register Volume 88, Number 222 (Monday, November 20, 2023)]
[Proposed Rules]
[Pages 80647-80648]
[FR Doc No: 2023-25700]

=======================================================================
-----------------------------------------------------------------------

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2023-1893; Project Identifier AD-2023-00389-A]
RIN 2120-AA64

Airworthiness Directives; FS 2001 Corp, FS 2002 Corporation, FS
2003 Corporation, Piper, and Piper Aircraft, Inc. Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM); extension of comment
period.

-----------------------------------------------------------------------

SUMMARY: This document announces an extension of the comment period for
the referenced NPRM, which proposed the adoption of a new airworthiness
directive (AD) for certain FS 2001 Corp, FS 2002 Corporation, FS 2003
Corporation, Piper, and Piper Aircraft, Inc. (Piper) airplanes. This
NPRM invited comments concerning the proposed requirement of replacing
any rudder equipped with a rudder post made from a certain carbon steel
with a rudder equipped with a rudder post made from a certain low-alloy
steel. This extension of the comment period is necessary to provide all
interested persons an opportunity to present their views on the
proposed requirements of this NPRM.

DATES: The comment period for the NPRM published on October 6, 2023, at
88 FR 69556, and scheduled to close on November 20, 2023, is extended
until February 20, 2024.

ADDRESSES: You may send comments, using the procedures found in 14 CFR
11.43 and 11.45, by any of the following methods:
     Federal eRulemaking Portal: Go to regulations.gov. Follow
the instructions for submitting comments.
     Fax:<PHONE_NUMBER>.
     Mail: U.S. Department of Transportation, Docket
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New
Jersey Avenue SE, Washington, DC 20590.
     Hand Delivery: Deliver to Mail address above between 9
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
    AD Docket: You may examine the AD docket at regulations.gov by
searching for and locating Docket No. FAA-2023-1893; or in person at
Docket Operations between 9 a.m. and 5 p.m., Monday through Friday,
except Federal holidays. The AD docket contains this NPRM, any comments
received, and other

information. The street address for Docket Operations is listed above.

FOR FURTHER INFORMATION CONTACT: Joseph Zuklic, Aviation Safety
Engineer, FAA, 2200 South 216th Street, Des Moines, WA 98198; phone:
(206) 231-3858; email: [email protected].

SUPPLEMENTARY INFORMATION:

Comments Invited

    The FAA invites you to send any written relevant data, views, or
arguments about this proposal. Send your comments to an address listed
under ADDRESSES. Include ``Docket No. FAA-2023-1893; Project Identifier
AD-2023-00389-A'' at the beginning of your comments. The most helpful
comments reference a specific portion of the proposal, explain the
reason for any recommended change, and include supporting data. The FAA
will consider all comments received by the closing date and may amend
this proposal because of those comments.
    Except for Confidential Business Information (CBI) as described in
the following paragraph, and other information as described in 14 CFR
11.35, the FAA will post all comments received, without change, to
regulations.gov, including any personal information you provide. The
agency will also post a report summarizing each substantive verbal
contact received about this NPRM.

Confidential Business Information

    CBI is commercial or financial information that is both customarily
and actually treated as private by its owner. Under the Freedom of
Information Act (FOIA) (5 U.S.C. 552), CBI is exempt from public
disclosure. If your comments responsive to this NPRM contain commercial
or financial information that is customarily treated as private, that
you actually treat as private, and that is relevant or responsive to
this NPRM, it is important that you clearly designate the submitted
comments as CBI. Please mark each page of your submission containing
CBI as ``PROPIN.'' The FAA will treat such marked submissions as
confidential under the FOIA, and they will not be placed in the public
docket of this NPRM. Submissions containing CBI should be sent to
Joseph Zuklic, Aviation Safety Engineer, FAA, 2200 South 216th Street,
Des Moines, WA 98198. Any commentary that the FAA receives which is not
specifically designated as CBI will be placed in the public docket for
this rulemaking.

Background

    The FAA issued an NPRM to amend 14 CFR part 39 by adding an AD that
would apply to certain FS 2001 Corp, FS 2002 Corporation, FS 2003
Corporation, Piper, and Piper Aircraft, Inc. (Piper) airplanes, as
listed in the NPRM. The NPRM published in the Federal Register on
October 6, 2023 (88 FR 69556). The NPRM was prompted by reports of two
non-fatal accidents involving airplanes designed and built by Piper
that were caused by broken rudder posts that structurally failed above
the upper hinge in flight. Both accidents occurred in Anchorage,
Alaska. The first accident occurred on June 8, 2020, and involved an FS
2003 Model PA-12 airplane and the second accident occurred on July 23,
2021, and involved an FS 2002 Model PA-14 airplane. Both airplanes
sustained substantial damage when the rudder structurally failed. After
examination, it was determined that the rudder posts fractured above
the upper hinge, the top portion of the rudder folded over the upper
tail brace wires, and the rudder posts were made from 1025 carbon steel
and fractured due to fatigue. This condition, if not addressed, could
result in a broken rudder and consequent reduced ability of the flight
crew to maintain the safe flight and landing of the airplane.
    In the NPRM, the FAA proposed to require replacing any rudder
equipped with a rudder post made from 1025 carbon steel with a rudder
equipped with a rudder post made from 4130N low-alloy steel.

Actions Since the NPRM Was Issued

    Since issuance of the NPRM, the FAA has received a request from the
Airplane Owners and Pilots Association (AOPA), the Short Wing Piper
Club, and other commenters to extend the comment period. The commenters
state that the NPRM is controversial and could drive substantial costs,
among other things. To be able to prepare informed and meaningful
comments with coordinated consensus among its members, AOPA requested
an extension of 90 days to the comment period.
    The FAA agrees with the request and has determined that it is
appropriate to extend the comment period for the NPRM to give all
interested persons additional time to examine the proposed requirements
and submit comments. The FAA has determined that extending the comment
period an additional 90 days will not compromise the safety of the
affected airplanes.

Extension of Comment Period

    The FAA has reviewed the requests for extension of the comment
period for this notice. The commenters have shown a substantive
interest in the proposed policy and good cause for the extension of the
comment period. Therefore, in accordance with 14 CFR 11.47(c), the FAA
has determined that an extension of the comment period for an
additional 90 days to February 20, 2024 is consistent with the public
interest, and that good cause exists for taking this action.
    Accordingly, the comment period for Docket No. FAA-2023-1893 is
extended until February 20, 2024.
    Because no other portion of the proposal or other regulatory
information has been changed, the entire proposal is not being
republished.

    Issued under authority provided by 49 U.S.C. 106(g), 40113, and
44701.

    Issued on November 16, 2023.
Caitlin Locke,
Director, Compliance & Airworthiness Division, Aircraft Certification
Service.
[FR Doc. 2023-25700 Filed 11-16-23; 4:15 pm]
BILLING CODE 4910-13-P