central & western ma cluster study and aso study update

1National Grid

Central & Western MA Cluster Study and ASO Study Update

December 5, 2019

Marlboro, MA

2National Grid

Agenda

02 ASO study Update

- Potential/On-going ASO studies

- GNF/PPA Process

- Prioritization

03 MA Data Portal Demo

04 Questions

00 Welcome/Safety

01 Transmission Study Update

- Total Study Overview

- Part 1: Study Overview

- Part 2: Study Plan

- Transmission Asset Management

- Next Steps

- Distribution Study Update

- Estimates by D-Study Area

3National Grid

Safety Message – Winter Driving Safety

Prepare Your Car –

❅ Keep a bundle of cold-weather gear in your car, such as extra food and water, warm clothing, a flashlight, an ice scraper,

blankets, medications, jumper cables, and more.

❅ Make certain your tires are properly inflated and have plenty of tread.

❅ Keep at least half a tank of fuel in your vehicle at all times.

❅ Never warm up a vehicle in an enclosed area, such as a garage.

❅ Be sure your cellphone is charged before traveling incase you get stuck.

Avoid a Crash –

❅ Avoid using cruise control in wintry conditions.

❅ Steer in the direction of a skid, so when your wheels regain traction,

you don’t have to overcorrect to stay in your lane.

❅ Accelerate and decelerate slowly.

❅ Increase following distance to 8 to 10 seconds.

❅ Stay home. Only go out if necessary.

4National Grid

This presentation has been prepared solely as an aid to

discussions between National Grid and interested

stakeholders, and should not be used for any other purposes.

This presentation contains high-level, general information (not

project specific) which may not be applicable in all

circumstances. National Grid makes no guarantees of

completeness, accuracy, or usefulness of this information, or

warranties of any kind whatsoever, express or implied.

National Grid assumes no responsibility or liability for any

errors or omissions in the content. Nothing contained in this

presentation shall constitute legal or business advice or

counsel.

No party is authorized to modify this presentation.

The Webex is being recorded.

Disclaimer:

01Central/Western MA Cluster StudyTransmission Update

Barry Ahern – Transmission Planning, NEP

Mike Porcaro – Distribution Planning, MECo

6National Grid

Goal: Progress a high volume of projects the most effective and efficient way

possible while identifying the appropriate upgrades to the system.

Transmission: Total Study Overview (May 2019)

40

200

180

760

0 100 200 300 400 500 600 700 800

>5MW

>1MW - 4.99MW

Magnitude of Applications in Western MA

MWs No. of Applications

Total: 937MW (240 Projects)

Part 1: 372MW

Part 2: 565MW

7National Grid

Part 1 of the study appears to be the most efficiently completed Non-FERC

transmission interconnection study in the USA with the most points of

interconnection.

• Part 1: 372 MW scope

• Projects: 90+ Projects

• Substations: 30+ Substations

• Timeframe: 6 months

Transmission: Part 1 Overview

Study Start: May 2019

Steady State Analysis - Stability Analysis

Short Circuit Analysis - PSCAD Analysis

8National Grid

Category 1: 14.5 MW

Category 2: 75.5MW

Transmission: Part 1 – Category 2 Initial Results

No Thermal Overloads

Overvoltages on • E-205

• A1/B2

• E5/F6

• A127/B128

• Y-25

9National Grid

Transmission: Part 1 – Category 2 Re-Evaluation

Assumptions (external)

• Commenced re-evaluating study assumptions within/outside of area

• We observed a number of reactive devices that could be switched off out side of the area

• The tweaks outside of area resolved a number of the voltage issues observed

• It resolved the voltages issues on a number of the offending circuits

• Brought the magnitude of the issues on the worst circuits down

Assumptions (Internal)

Working with Distribution Planning, we reviewed:

• Would shifting load at certain stations be possible

• Would moving Gen address the issues

Validation of Impacts

10National Grid

Transmission: Part 1 – Category 2 Potential Solutions

Solutions Assessed for Category 2

1. Utilization of Inverters

• Issues with Voltage coordination

2. Utilization of Distribution Capacitor Banks (SMART)

• Proven to be viable

3. Distribution Reactors

4. Transmission Reactors

SMART Capacitor Bank Solution

• Utilization of existing capacitor banks on feeders was an innovative method to resolve the adverse

impacts observed

• This is not a fully scalable solution

• This work also fit the Grid Mod program.

Result

In 4 months (August 2019) - NG brought 90MW of GNFs to the RC for approval.

11National Grid

Stakeholder Meeting (August 13) – Adverse Impacts Observed

Thermal Solutions (1 of 3 Options):

1. Reconductor 10 mile of the B2 line between Otter River and Pratts Junction

2. Installation of a Battery at East Westminster

3. Limited Operation: Preventing approximately 20MW from interconnecting on eastern section of B2 line

Voltage

1. Direct Transfer Trip Schemes between Pratts Junction and Both Otter River and Crystal Lake on the A1

and B2 circuits

2. All other types of solution identified when assessing Category 2

Affected Party Engagement

• Challenge to ISO-NE that one of the assumptions being utilized was not accurate

• Subsequent letter to ISO-NE

• Assumptions were re-evaluated and remained unchanged

Transmission: Part 1 – Category 3 (282MW)

12National Grid

New Study Inputs

1. Continued review = PP5-6: Section 3.4 No Increase in Conditional Dependence

• Increased dependency on Vernon Hydro following N-1 event

• Result: New Upgrade

A1: Span remediation between Royalston - Otter River ($)

2. Attrition – 372MW to 325MW

Transmission: Part 1 (Finalizing Report)

Scorecard in September 2019:

1. Thermal: Reconductoring/Battery (millions of $)

2. Voltage: Reactors (millions of $)

3. Stability: Protection schemes ( millions $)

4. PSCAD – Potentially not feasible in timeframe

5. Short Circuit: No issues identified

13National Grid


October 2019: 325MW

1. Thermal: Reconductoring/Battery on B2 Circuit (millions of $)

2. Voltage: Reactors multiple locations (millions of $)

3. Stability: Protection schemes involving multiple stations ( millions $)


5. A1: Span remediation between Royalston - Otter River ($)

Thermal: Re-ran All Cases

1. Revised MW numbers did not trigger the overload

2. No thermal remediation was deemed necessary

14National Grid


October 2019: 325MW



3. Stability: Protection Schemes involving multiple stations ( millions $)



Voltage: Internal Review

Transmission

• Assessed the settings of equipment in the area

• Identified is reasonable action could be taken to improve voltages in the area

Distribution

• Applied all of the SMART Cap solutions available in this area

15National Grid


October 2019: 325MW






Residual Voltage Issues: Reviewed 6 solutions

1. Operator Action - Discussed with NG control centers and formally proposed to ISO-NE

2. Inverters – Coordination not possible

3. Distribution Cap. Banks – Reliability concern with this occurring at Peak

4. Direct Transfer Trip – Determined optimal

5. Distribution Reactors

6. Transmission Reactors

16National Grid


October 2019: 325MW





5. A1: Span Remediation between Royalston - Otter River ($)

Stability: Reviewed All Related Standards

This included

• ISO-NE SRD

• NG ESB 756

• IEEE 1547

• Identified if Momentary Cessation was applied - adverse impacts relating to ISO-NE PP3 could be mitigated

• ISO-NE confirmed that this change would be appropriate

• Letter to Developers in Mid-October/NG ESB 756 to be re-written

17National Grid


October 2019: 325MW






PSCAD

• Reviewed final scope with contractor

• Agreed on assumptions to implement in order to complete study

• Set expectations for outputs

18National Grid


October 2019: 325MW





5. A1: Span Remediation between Royalston - Otter River ($)

A1 Remediation: 3 Potential Solutions

• Transmission Tower Replacement

• Tensioning

• Distribution Relocations

Scope Change (4.9MW withdrew)

Re-ran the cases and the remediation was deemed not necessary

19National Grid

Reliability Committee - November 19

• Submission of Agenda on October 31

• Submission of 56 Proposed Plan Applications by November 5

• Following Reliability Committee recommendation for approval

• ISO-NE made determination that an alternative solution as discussed with NG in October would be

acceptable

Part 1 - Conclusion

End Results for Part 1

Category 1 (14.5MW – No Cost to Developer)

- No requirement for study

Category 2 (75.5MW – No Cost to Developer)

- Utilization of SMART Caps. to mitigate voltage issues

Category 3 (230MW – No Cost to Developer)

- Tap Change on at Adams and maximized utilization of SMART Caps.

Lessons Learned

• More time is required to review PPA prior to RC

meeting

• Big changes or changes too late in the process will

impact this timeframe

20National Grid

Part 2 – Scope Review

Scope – May 2019

• Total: 937MW

• Part 1: 372MW

• Part 2: 565MW

• Projects: 90+ Projects (Part 1)


Scope – November 2019

• Total: 751MW

• Part 1: 325MW

• Part 2: 431MW

• Projects: 120+ Projects (Part 2)


Notes:

• Part 2 will include 5 new distribution substations & 9 rebuilds

• The impact of the attrition is being assessed relative to the distribution solutions

• A population of the developments in Part 1 will be mapped to new stations

• Transmission need to proceed with the study assuming no changes

21National Grid

December 2019 – January 2020

Draft Steady State Analysis Results Dec 15

Validate all PSCAD Models Dec 9

Validate all Stability Models Dec 21

Determine Steady State Analysis Solutions Dec 15 – Jan 1

Commence PSCAD and Stability Study Jan 6

Commence Short Circuit Analysis Jan 12

Part 2 – Timeline (0-6 weeks)

22National Grid

January 2020 – February 2020

Finalize Short Circuit Analysis Feb 7

Determine Short Circuit Analysis Solutions Feb 7 – Feb 24

Draft PSCAD and Stability Reports for review Feb 10

Finalize Stability Study & Solutions Feb 10 – March 1

Draft Study Complete March 10

Part 2 – Timeline (6-10 Weeks)

23National Grid

March 2020 – April 2020

Complete All PPAs (120) March 1 – March 25

Complete all analysis prompted by review March 15

Final Cycle by Affected Parties March 1 to March 25

Submit Agenda, PPAs and Study March 13

Comments from ISO-NE/Affected Parties March 25 – April 12

Present Study at April RC April 15

Part 2 – Timeline (10-14 Weeks)

24National Grid

What is an Asset?

What are National Grid’s Transmission Assets?

Transmission Asset Management?

Asset Management focuses on embedding risk-based, value-driven, whole life decision-making for our assets. All decisions to spend should be prudent

The management system back-bone and platform that unifies all facets of National Grid

• Bridges siloed decision-making stakeholders and processes to make holistic decisions on assets

“An item, thing or entity that has potential or actual

value to an organization” – ISO 55000

“…the coordinated activity of an organization to

realize value from assets.” – ISO 55000

Substation, Circuits, Breakers, Switches, Communications, Security

25National Grid

Transmission Asset Management Framework

26National Grid

• Illustration of Asset Condition Projects in next 5 years in Western/Central MA

• Overlap on assets targeted with potential DG prompted upgrades

• If DG prompts an upgrade where an asset condition is planned

• DG will only pay for what is not already in the scope

Map of Transmission Asset Projects

27National Grid

High Level Cluster Timeline

Jan 2020 Identify the final transmission upgrades required for thermal/voltage

Feb 2020 Conclude Study (PSCAD/Stability/Short Circuit) with relevant upgrades

March 2020 Submit all of the PPAs to ISO for review

Determine overlap with Asset Projects and Upgrades

Determine cost allocation for upgrades

April 2020 Final Presentation to Reliability Committee

Transmission Next Steps

28National Grid

Distribution Area Study Update

Michael Porcaro – Distribution Planning, MECo

29National Grid

Areas requiring MECo Distribution System upgrades

• Barre >48 MW

• Belchertown >32 MW

• Athol >42 MW

• Gardner >85MW

Total in excess of 315MW

Upstream affect on additional substations that connect to the transmission lines

serving above areas

• Considering these additional affected subs, >750MW seeking to interconnect

Perspective:

• Vermont Yankee, Nuclear Power Plant, Vernon VT: 620 MW (decommissioned 2014)

• Typical “Heavily Loaded” 15kV Feeder: ~10 MW

• “Worcester Area Load”: approx. ~165 MW (low period)

Level of DG Saturation

• Leicester >48 MW

• Brookfield >16 MW

• Palmer >43 MW

30National Grid

Distribution Planning identified 7 specific concentrated areas currently

encompassing over 20 substations in MECo’s service territory.

◦ 5 new substations

◦ 9 substations to be significantly expanded and/or rebuilt

◦ 2 substations to be retired

◦ Remaining substations to undergo upgrades in support of feeder level system

modifications

Current expectations for Distribution Level solutions

◦ New substations and/or expansion of existing

◦ Rearrangement of distribution feeders

◦ Alternative distribution feeder voltage class

Total approximately $370M of infrastructure modification

Distribution Area Preliminary Analysis

31National Grid

Gardner Area - $96M; 5yrs

Total of 22 applications comprising >85MW

Rebuild East Winchendon Substation at existing location:

• Replace (1) existing 115kV:13.8kV substation transformer with 55MVA unit

• Install (1) new 55 MVA 115 kV:13.8 kV and (1) new 75 MVA 115 kV:34.5 kV substation transformers

Retire existing Westminster Substation & replace with new at new location:

• Install (2) new 55 MVA 115 kV:13.8 kV and (1) new 75 MVA 115 kV:34.5 kV substation transformers

New transmission taps to new substation transformers

New distribution feeder installation and area feeder reconfiguration

Values shown are approximate, for reference purposes of this presentation. Work scope describes the preliminary

proposed distribution solution which will be reviewed by the ASO. This solution is subject to change in whole or part

pending the results of the ASO studies. Does not reflect required system modifications for ASOs.

Ashburnham

Crystal Lake

E. Westminster

E. Winchendon

Whitmanville (New

Replacing Westminster)

Area Substations

32National Grid

Leicester Area - $39M; 5yrs


Upgrade North Oxford Substation at existing location:

• Install (1) new 55 MVA 115 kV:13.8 kV substation transformer

Retire existing Leicester Substation and replace with new near Stafford St in Leicester:

• Install (2) new 55 MVA 115 kV:13.8 kV substation transformers

Install 3V0 at Pondville Substation


New distribution Feeder installation and area feeder reconfiguration


proposed distribution solution which will be reviewed by ASO. This solution is subject to change in whole or part pending

the results of the ASO studies. Does not reflect required system modifications for ASOs.

Pondville

N. Oxford

Webster St.

Stafford St. (New Replacing

Leicester)

Area Substations

33National Grid

Brookfield Area - $54M; 4yrs


Upgrade Meadow St Substation at existing location:

• Install (1) new 55 MVA 69kV:13.2kV substation transformer

Install new substation near Cronin Rd in Brookfield:

• Install (2) new 55 MVA 115 kV:13.2 kV substation transformers






Lashaway

Brookfield (New)

Meadow St.

Area Substations

34National Grid

Athol Area - $52M; 4yrs


Upgrade Royalston Substation at existing location:

• Replace existing 3.75MVA, 69kV:4kV transformer with 40MVA, 69kV:13.2kV

Install new substation in New Salem:


Upgrade Wendell Depot Substation at existing location:

• Replace (1) existing 20MVA, 115kV:13.8kV substation transformer with 55MVA unit

• Install (1) new 55 MVA 115 kV:13.8 kV substation transformer






Chestnut Hill

Wendell Depot

Royalston

New Salem (New)

Area Substations

35National Grid

Palmer Area - $62M; 4yrs


Upgrade Palmer Substation at existing location:

• Replace (1) existing 20MVA, 115kV:13.2kV substation transformer with 55MVA unit


Upgrade Little Rest Rd Substation at existing location:








Little Rest Rd.

Palmer

Shearer’s Corner

Area Substations

36National Grid

Belchertown Area - $14M; 4yrs

Total of 13 applications comprising 32MW

Upgrade Five Corners Substation at existing location:


Upgrade Thorndike Substation at existing location:







Belchertown

Five Corners

Thorndike

Area Substations

37National Grid

Barre Area - $53M; 4yrs


Upgrade Barre Substation at existing location:

• Replace (2) existing 12.5MVA and 9.375MVA, 115kV:13.8kV substation transformers with 55MVA units

Install new Substation in Barre (tentatively named Powder Mill):


New Transmission taps to new substation transformers

New Distribution Feeder installation and area feeder reconfiguration




Barre

Powder Mill (New)

Ware

Area Substations

38National Grid

Next Steps:

• Continue to collaborate with ASO’s as needed

• Finalize distribution line reconfigurations, load flow, and protective device analyses

• Continue coordination to ensure viable solution

- Constructability

- Operational requirements

- Cost effective

- Maintaining overall safety and reliability

• Commence Detailed Studies after Cluster study has been reviewed and approved by ISO

• Adjust distribution interconnection solutions as needed based on results of ASO study

MECo Distribution Study Status Summary

02ASO Study Update

Pending/On-Going ASO Studies

GNF/PPA Process

Project Prioritization

National Grid

Will Kern – Customer Energy Integration

40National Grid

Due to the stagnant load growth and the increase in DG interconnections on

the Distribution System in MA, ISO-NE has a growing concern about the

back feed of generation onto the Transmission System. Because of this

concern and the desire to operate the Transmission EPS safely and reliably,

there has been an increase in the need for Affected System Operator (ASO)

studies. Generation thresholds have been communicated to help

Massachusetts Electric Company (MECo) identify potential issues and

where ASO studies may be required. MECo, New England Power (NEP), and

ISO-NE continue to work closely to determine the most expedient path

forward for each interconnection project.

Due to the DG saturation levels in MA, delays during the study stage of the

interconnection process should be expected in all National Grid territories.

MA Transmission Saturation

41National Grid

Northern (NEMA) ASO Studies

• Billerica (Non-Comprehensive)

- 5.43MW to be studied and 3 projects

- Study/payment status – in progress

- Impacted Distribution Substations

◦ Meadowbrook

◦ Billerica

• King St / W. Amesbury (Comprehensive)


- Study/payment status – not commenced


◦ W Newbury

◦ Topsfield

• W Amesbury/Ward Hill (Non-Comprehensive)




◦ W Amesbury

◦ King St

◦ Newburyport

◦ Beech St

◦ N Haverhill

◦ Whittier

42National Grid

Southern (SEMA) ASO Studies

• Swansea (Non-Comprehensive)


- Study/payment status- commenced


◦ Swansea

◦ Mink St

• Attleboro/Uxbridge (Non-Comprehensive)


- Study/payment status – commenced


◦ Depot St

◦ S Wrentham

◦ West St

• Brockton (Non-Comprehensive)

- 11.39MW to be studied, 4 projects

- Study/payment status –commenced


◦ Belmont

◦ Easton

◦ Mill St

• Dighton (Non-Comprehensive)

- 5.37MW to be studied, 2 projects

- Study/payment status –commenced


◦ Dighton

43National Grid

Southern (SEMA) ASO Studies

• Uxbridge/Whitins Pond (Comprehensive)


- Study/payment status – commenced


◦ Uxbridge

◦ Whitins Pond

◦ Mendon

• Chartley Pond (Non-Comprehensive)


- Study/payment status - commenced


◦ Chartley Pond

| [Insert document title] | [Insert date]

44National Grid

Western MA ASO Studies

• Fiskdale – (Level TBD)




◦ Fiskdale

• Laurel Cir – (Non-Comprehensive)




◦ Laurel Circle

• North Marlboro – (Level TBD)



• Pleasant St (Level TBD)


- Study/payment status


◦ Sheffield

◦ Stockbridge

◦ Risingdale

◦ W.M.E.Co substations

• Florence Jct (Level TBD)


- Study/payment status


◦ Florence Jct (W.M.E.Co substations)

45National Grid

National Grid GNF/PPA Process*

• For Interconnection applications between 1MW - 5MW

• Screening will review for potential of ASO Study and provide screening memo and Distribution

System Impact Study (DSIS) costs

• At or around 20BD mark, ISO-NE will be contacted and consulted on need for ASO study

- If customer chooses to move forward and pay the DSIS fee

- The Distribution study will continue unless/until the need for ASO study has been determined

◦ This may be identified at screening and the DSIS will go on ASO Hold at this time

• ISO-NE will review the GNF to determine the potential for impact to the Transmission system

• ISO-NE will determine level of study required:

- Level 0,1 – no adverse impact, GNF can progress to RC

◦ Non-comprehensive study may be required as required by ISO-NE – 3-5 month study timeframe

- Level 3 (comprehensive) – 4-6 month study timeframe

- MECo and NEP will group applications if necessary for expediency

- Study will be scoped and ASOs will be engaged by NEP

*This process subject to change due to MA DPU Docket 19-55

46National Grid

National Grid GNF/PPA Process* (continued)

• ASO study fees will be determined (based on level of study requires) and invoiced to the customer

- Will have 20 BD to make ASO study fee payment

- Customer will be requested for any required information to proceed with the ASO study

- If payments are not received on time, the project will be removed from the current ASO study

◦ The project will be given a 1 time, 10 BD opportunity to make payment to reserve inclusion in future ASO studies

◦ Failure to make this payment will result in the application being withdrawn

• ASO Study will commence

• Once ASO study is complete, GNF/PPA will be submitted to the ISO for inclusion on RC agenda

- Customer will be notified if Transmission modifications will be required

• Once GNF/PPA is approved by the RC, the ASO hold will be removed and DSIS will continue

- GNF is considered “approved” once the company receives the approval letter from ISO-NE

• If Transmission modifications are required they will be included in the Interconnection Service Agreement

(ISA)

- These modification will be expected to be completed before the project can interconnect

*This process subject to change due to MA DPU Docket 19-55

47National Grid

GNF/PPA process Update

Implications:

• Additional time required during

the study stage

• Limitation on project changes

• Need to update the ISO-NE if a

project is withdrawn

• Earlier notification of potential

Transmission impacts

• ISA will include all total (T&D)

cost estimate, scope, and

schedule

ASO Study Communications:

• DPU Interim Guidance

- Customer(s) will be notified of need for study as soon as company is made aware

◦ Including: level and expected timeline of study, area/region impacted, # of MW

and applications in the study, and if additional project info is required

- ASO study specific communication bi-weekly until study is kicked-off

- ASO study specific communication monthly once study has started

• ISA will include total (T&D) cost estimate, scope, and schedule

48National Grid

• Has customer paid its full construction advance for system

modifications

• When did the MECo receive customer payment?

• What is the date of the customer’s anticipated authority to

interconnect?

• What stage is the project within the MECo’s construction

process?

• How far along is the customer’s construction (developers may

need to self-certify the responses to these questions)?

- Does customer have all necessary local permits to construct?

- Does customer have site control?

Post-ISA Prioritization System

49National Grid

• What date was the application deemed complete?

• Has the customer filled out, signed, and returned the Land Use

Certification delivered on November 4th?

- This is not just about “site control”

- This is about project maturity and prioritization.

- The certification is not mandatory

- no projects will be withdrawn if not returned

- More mature projects will be prioritized if opportunities to progress

projects presents during Part 2 of the Cluster Study

Pre-ISA Prioritization System

03Data Portal Map Demo

National Grid

Vishal Ahirrao – Customer Energy Integration

51National Grid

What is the MA System Data Portal?

A new web-based tool that houses a collection of interactive maps hosted on ARCGIS.

Each map provides the location and specific information for

selected electric distribution lines and associated substations

within the National Grid electric service area in Massachusetts.

Find the MA System Data Portal at the National Grid Project

Guidance Page for Massachusetts:

https://ngus.force.com/s/article/Massachusetts-

System-Data-Portal ( best used in Chrome)

https://ngus.force.com/s/article/Massachusetts-System-Data-Portal

52National Grid

Major Features

• The map sets have been updated on October 25 with CY Electric Grid Configurations and 2018 Feeder Peaks. 2019 Peaks will be uploaded before End of Year 2019Electric Map

• National Grid now posts our Annual Reliability Report (ARR) which contains much of the information in the MA Portal but in tabular form. Located in the “Company Reports” tab.

Annual Reliability Report

• National Grid has posted a color coded map which highlights Feeders that are close to their max rating based on 2018 Loads. This can help developers locate NG’s desirable places for interconnection.Heat Map

• National Grid has posted a DG Hosting Capacity Map which is color coded by Available Hosting Capacity (Under Development). It also shows aggregate connected and pending DG by Feeder.

Hosting Capacity Map

• National Grid is also including 3V0 information and aggregate connected and pending DG of transformer banks on an individual Feeder level.

Substation Information

53National Grid

Massachusetts Distribution Assets Overview

54National Grid

Massachusetts Heat Map Overview

55National Grid

Massachusetts Hosting Capacity Overview

56National Grid

Stakeholder Involvement

Please reach out to [email protected] with any questions or

suggestions for improvement regarding the Portal.

Please contact [email protected] for

questions regarding NWA and to request to be added to our NWA

Stakeholder distribution list.

mailto:[email protected]

mailto:[email protected]

04QUESTIONS?

central & western ma cluster study and aso study update

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