SUMMARY REPORT. 10 Year Transmission System Assessment

2018 SUMMARY REPORT 10 Year Transmission System Assessment

Agility, flexibility needed to plan for Long term transmission planning has always been a complex undertaking, but it was relatively consistent in the days of steady load growth and a stable generation mix. But conditions in the early 21st century are no longer as predictable as they were in the past, adding new challenges to the process. As a transmission only electric utility, we collaborate with our customers to determine needed replacements, expansions and connections to the grid. Recent changes in generation and the energy marketplace have required us to be flexible and agile in our planning to accommodate customer needs. In today s marketplace, our customers expect us to respond quickly. In fall 2017, Foxconn selected Wisconsin for its first U.S. based manufacturing facility for flat screen technology. The Mount Pleasant Tech Interconnection Project was developed to respond to the needs of a facility that would constitute the largest load at a single substation in ATC s service territory. We filed an application in January to build a new substation and associated transmission lines with the Public Service Commission of Wisconsin, which approved the project in July. Construction will start this fall and the project will be in service in late 2019. Transmission investments Projections from past and current Transmission System Assessments 2014 2015 2016 2017 2018 Specific Network Projects Regional Multi Value Projects $1.4B $1.4B $1.3B $0.7B / $1.0B* $0.5B $0.5B $0.5B $0.5B $0.4B $0.3B Asset Maintenance $1.2B $1.4B $1.4B $1.4B $1.5B Other Capital Categories $0.2B / $0.8B $0.4B / $1.2B $0.4B / $1.2B $0.3B / $0.8B $0.5B / $1.1B Total 10 Year Capital Cost $3.3B / $3.9B $3.7B / $4.5B $3.6B / $4.4B $2.8B / $3.6B $2.8B / $3.4B * The Specific Network Projects range in 2017 reflects the fact that Northern Area Reliability Assessment projects in the 10 Year Assessment project list and in the MISO Transmission Expansion Plan database may be replaced by generation being considered in the Midcontinent Independent System Operator generation queue. 2 AMERICAN TRANSMISSION CO.

Minnesota Kingsford Michigan changing energy marketplace Wisconsin De Pere Madison Cottage Grove Illinois Pewaukee Headquarters ATC Offices Upper Michigan Energy Resources Corp., a subsidiary of WEC Energy Group, proposed in early 2017 to add 180 megawatts of generation at two sites in the Upper Peninsula. The project was approved later that year, and construction began immediately. This allowed us to scale back projects identified in our Northern Area Reliability Assessment. UMERC s two plants are located near existing transmission infrastructure and will require two new substations and only a short segment of transmission line to connect the facilities. Generation retirements have a large impact on the transmission grid. We anticipate that more than 30 percent of the coal fired generation in our service territory will be retired by the end of 2019. With the retirement of the Kewaunee Nuclear Station in 2013, we canceled a pair of 50 mile, 138 and 345 kv lines that had been in the planning stages for several years the change in generation allowed the need to be satisfied instead with a new substation that went into service this year. The announced closing of the Pleasant Prairie Power Plant in southeastern Wisconsin meant that another transmission connection into northern Illinois was no longer needed, and the Wisconsin Illinois Electric Reliability Project was canceled. We also work with our customers to evaluate cost effective non transmission solutions when examining the condition of our aging assets. Recently, we made the decision to retire a 69 kv line in northeastern Wisconsin that was in poor condition when we determined, with Wisconsin Public Service, that the local distribution company s two substations served by the line could be tied into a nearby rebuilt 138 kv line for about half the cost. These examples demonstrate the dynamic nature of the electric industry today. That s why it s prudent to conduct an annual review of market conditions and transmission needs. Our 10 year forecast calls for a slight decrease in capital expenditures from last year, with $2.8 to $3.4 billion in system improvements. This document contains a summary of ATC s planning initiatives, and an overview of asset renewal and network driven projects in each of our planning zones. For more detailed information, please visit www.atc10yearplan.com. Jim Vespalec Director, Asset Planning & Engineering Ron Snead Vice President, System Planning 2018 10-YEAR ASSESSMENT 3

Regional and economic planning ATC is an active participant in a variety of efforts to address regional and inter regional planning initiatives to maintain a reliable grid and capture economic benefits in a dynamic energy marketplace. Policy initiatives to curb greenhouse gas emissions and expand the use of renewable energy continue to evolve, and we work closely with our customers to plan for an electric transmission system that will serve their needs well into the future. MIDCONTINENT INDEPENDENT SYSTEM OPERATOR TRANSMISSION EXPANSION PLANNING MISO planning studies address long and short term issues as well as targeted needs. Long term studies primarily look at value based options that provide economic benefits in the 10 to 20 year horizon. Short term planning is primarily driven by transmission owners reliability and North American Electric Reliability Corporation compliance needs in a five to 10 year period. ATC staff participates in the MISO short term reliability and economic studies in a variety of ways: ensuring accurate project information is included in the MISO database, building and reviewing models, correlating needs identified by MISO analyses with specific ATC projects and participating in various studies and stakeholder forums. MARKET CONSTRAINTS Two of the five narrowly constrained areas identified in the MISO region are associated with ATC, and we continue to track these as well as other constraints. Such tracking assists in planning projects that alleviate congestion within the MISO market. OTHER MISO PLANNING ACTIVITIES Our planning staff participates in various technical and policy discussions and provides future direction for Midwest Transmission Expansion Plan activities. We also are involved in joint planning studies with neighboring regional transmission organizations, including PJM and SPP. MISO and PJM coordinate, conduct and analyze several market efficiency project studies. This analysis is reviewed by an inter regional planning stakeholder advisory committee, which typically examines economic projects that could benefit both Regional Transmission Organizations and qualify for cross border cost sharing. 4 AMERICAN TRANSMISSION CO.

Major projects update BADGER COULEE This fall, we expect to energize the 180 mile, 345 kv Badger Coulee transmission line, one of MISO s 17 Multi-Value Projects designed to deliver significant benefits to electric consumers throughout the Upper Midwest. A portion of the project from the Cardinal Substation to the North Madison Substation was placed in service in fall 2017. Developed jointly with Xcel Energy, the line will: offset the need for about $190 million in lower-voltage upgrades in western Wisconsin, increase access to the wholesale energy market and provide between $118 million and $700 million in net economic benefits over the life of the line, and establish another pathway for renewable energy into Wisconsin with a connection to key load centers. BAY LAKE The Bay Lake Project is a package of proposals that address the delicate, shifting balance between generation, load and transmission in the northern portion of our service area. The North Appleton Morgan project was placed in service in September 2018, ahead of schedule and under budget. It includes 345 kv and 138 kv lines from our North Appleton Substation in Outagamie County to the Morgan Substation in Oconto County, Wis. Both substations have been expanded and additional work was required at 11 other substations. A new substation, Benson Lake in Marinette County, was placed into service in July 2017. It includes a large voltage control device. North Appleton Morgan was approved by the Public Service Commission of Wisconsin in May 2015, with an authorized cost of $328 million. (continued on page 6) 2018 10-YEAR ASSESSMENT 5

Major projects update continued The Mount Pleasant Tech Interconnection Project will serve up to 230 MW of load, the largest load connected to a single substation on our system. CARDINAL HICKORY CREEK ATC, ITC Midwest LLC and Dairyland Power Cooperative filed an application in April with the Public Service Commission of Wisconsin for a 102- to 120 mile, 345 kv transmission line connecting Dubuque County, Iowa, to Dane County, Wis. The Cardinal-Hickory Creek Project is another MISO Multi-Value Project. Studies indicate that it will deliver benefits to local communities and the Midwest region by: improving electric system reliability locally and regionally, delivering $23.5 million to $350.1 million in net economic benefits, and connecting to other 345 kv transmission lines in the Upper Midwest and helping to enable 25 gigawatts of cost effective renewable energy to be delivered to communities in the region. If approved by Wisconsin and Iowa regulators, the project is estimated to be in service in 2023. SPRING VALLEY NORTH LAKE GENEVA Construction is underway on the $71 million Spring Valley North Lake Geneva Project, which was approved by the Public Service Commission of Wisconsin in spring 2016. This project is needed to meet an increase in electric demand in Walworth and Kenosha counties in Wisconsin. The project involves: construction of a new 138 kv transmission line of approximately 23 miles, stretching from the North Lake Geneva Substation in southern Walworth County to the Spring Valley Substation in western Kenosha County, construction of a new 138 kv and 69 kv substation on an ATC owned parcel along Highway 50 in the Town of Wheatland, construction of a new 69 kv transmission line to connect the new substation to the existing Twin Lakes Substation in Twin Lakes, and other power line modifications. The project is expected to be placed into service in 2019. 6 AMERICAN TRANSMISSION CO.

FINGER ROAD CANAL The rebuild of a 69 kv line in northeastern Wisconsin, along with associated substation work, was approved by the Wisconsin Public Service Commission in spring 2017 at a cost of $60.7 million. About 55 miles of line on 1950s vintage wood poles between Finger Road Substation and Canal Substation will be rebuilt. The line serves seven distribution substations in northern Kewaunee County and Door County. The project includes: the replacement of 834 wood pole structures, the replacement of line conductor and addition of a fiber optic shield wire, the update at terminal end substations of jumpers, selective bus conductor, and disconnect switches. Construction is scheduled to complete in January 2021. MOUNT PLEASANT TECH INTERCONNECTION This project is designed to support Foxconn, which upon completion will be one of the largest manufacturing facilities in the nation with a campus build out anticipated to be approximately 22 million square feet. The initial projected electric usage would be 200 megawatts at this manufacturing facility, with an additional 30 MW of expected economic growth in the surrounding area. The electric load required for Foxconn s operations will be the largest connected to ATC s transmission system at a single substation. The project cost is estimated to be about $117 million and includes: constructing a new 345 /138 kv Mount Pleasant Substation, looping the Racine Pleasant Prairie 345 kv line into the new substation, stringing a new Racine Pleasant Prairie 345 kv circuit in the vacant position on existing structures and looping this new circuit into the new substation, reconfiguring the Racine Substation 345 kv bus, rerouting the Pleasant Prairie and Bain 345 kv line, uprating the Elm Road Racine 345 kv line, and constructing four new 138 kv underground lines (~400 feet) from the Mount Pleasant Substation to serve a customer owned substation. ATC submitted the CPCN application in late January 2018 to the Wisconsin Public Service Commission, which approved the project in July. Construction is underway. All electrical infrastructure has an expected in service date of late 2019. MACKINAC MCGULPIN 138 k V SUBMARINE CABLE REPLACEMENT ATC has plans to replace the two 4 mile, 138 kv submarine transmission lines connecting the Upper Peninsula of Michigan to lower Michigan at an estimated cost of $105 million. The Mackinac McGulpin 138 kv submarine cable replacement project was submitted for MISO review in the MTEP18 planning cycle. The project was developed for the following reasons: Two 138 kv submarine circuits were damaged by an anchor strike on April 1, 2018. Three working cables have been reconfigured to form one 138 kv circuit. The project will restore the eastern UP to the level of reliability it had before the April 1 event. The integrity of the remaining cables is of concern. The remaining cables contain a mineral oil based dielectric fluid; a submarine cable failure could result in a fluid leak into Lake Michigan and Lake Huron. As proposed, the project is estimated to be in service in 2021. (continued on page 8) 2018 10-YEAR ASSESSMENT 7

Major projects update continued BAYPORT PIONEER The rebuild of a 69 kv transmission line in northeastern Wisconsin, along with associated substation work, will be submitted to the Wisconsin Public Service Commission in spring 2019 at a cost of $51.7 million. Approximately 22 miles of line on 1910s vintage wood poles running between Bayport Substation and Pioneer Substation will be rebuilt. The line will serve three distribution substations in Brown County and Oconto County. The Bayport Pioneer asset renewal project consists of the following: rebuilding the line between Bayport and Pioneer substations with double circuit structures, stringing both Bayport Pioneer lines, combine, and operate as one line at 138 kv, converting Suamico and Sobieski substations to 138 kv operation, and de energizing the Pulliam Bayport 69 kv section of line. The project is scheduled to be in service in December 2021. JUNEAUTOWN INTERCONNECTION The Juneautown Interconnection Project is a 138 kv distribution transmission interconnection needed to meet We Energies growing reliability and economic needs. The cost of the project is estimated to be $34.1 million and includes: a new Juneautown 138 / 13.2 kv gas insulated substation, looping the 138 kv line between Haymarket and Harbor substations to feed the new substation, and routing the new line segments through new underground corridors. An application for a Certificate of Authority was filed with the Public Service Commission of Wisconsin in January 2018 and was approved in August. Construction is scheduled to begin in fall 2019. The facilities are scheduled to be in service approximately 12 months after construction begins. 8 AMERICAN TRANSMISSION CO.

By focusing on life-cycle cost, our asset management program helps us efficiently maintain and upgrade our older transmission assets. Our progress One of ATC s top priorities has always been electric reliability. With that focus, ATC has strengthened the grid to enable our customers to participate in and reap the benefits of the wholesale energy market. As we continue to use our system wide planning process to effectively and economically improve reliability, more emphasis is being placed on the need to efficiently maintain and upgrade our older assets. Our asset management program is focused on the life cycle management of transmission assets. The objective is to ensure assets perform the required function in a sustainable manner while managing life cycle cost. Coordination of design, commissioning, operation and maintenance is crucial to developing the replacement strategy of the assets. Asset renewal is mainly driven by public and worker safety, regulatory compliance, reliability, condition and operational performance. Our single focus, transmission only business model has produced significant results for our customers over the years. Over the past ten years, we have: upgraded more than 895 miles of transmission line, improved 105 electric substations, built 25 new transmission lines (367 miles) connected 1,980 MW of new generation at 12 sites, Includes 430 MW of renewable generation at 6 sites saved customers millions in reduced energy costs with access to the marketplace and lower line losses, increased import and export capability, and improved transmission reliability. Due in large part to our asset management efforts, ATC consistently achieves better reliability performance than our industry peers in all voltage classes. 2018 10-YEAR ASSESSMENT 9

What drives the need for transmission system improvements? Early in our operational existence we focused on creating a smooth flowing electrical highway to more reliably serve our customers. This involved finding the logical places in our service area to develop transmission projects. Major, network driven projects accounted for significant investment in our 345 kv system. As we were making our network more interconnected and reliable, we also analyzed the life cycle maintenance of our existing assets, focusing on an asset management strategy to complement and create synergies with our network additions. Today, our effective management of transmission assets complements our planning strategy for electric reliability and economic benefits. In a collaborative process, our asset management and planning teams work with other functional groups and stakeholders to achieve the best solutions to transmission system needs. Asset management staff monitor the system through maintenance and inspection programs to identify issues related to equipment performance or condition. Equipment needing attention is discussed internally and with customers to determine if replacement in kind is required and if other reliability needs exist within the geographic area. Needs are evaluated using various options to determine the best means of maintaining reliability. These discussions with customers occur at 10-Year Assessment stakeholder meetings and MISO System Planning Meetings. COMMON NEEDS THAT DRIVE SYSTEM IMPROVEMENTS INCLUDE: New or retiring generation changes in the generation impact on the transmission system, the location and amount of power flowing as well as system stability Economics greater access to the wholesale energy marketplace provides economic opportunities to utility customers Enhanced NERC reliability standards require a greater degree of redundancy and analysis to assure reliable, resilient operation Public policy renewable energy mandates and pending air quality regulations will affect how the transmission system will be built and used Asset renewal maintaining the system in good operating condition extends its life and improves safety and performance Interconnections changes in how our customers distribute electricity to consumers require new or modified transmission facilities Load changes while overall load growth is low, loads are appearing and disappearing, changing power flows on the system New technologies synchronized phasor measurements, demand side management and distributed energy resources affect how the grid is planned and operated to maintain reliability Communications improvements in communication technology, such as fiber optics, are incorporated to support an ever increasing need to see and control what is happening on the transmission system in real time 10 AMERICAN TRANSMISSION CO.

Plans and proposals for the transmission system For planning purposes, ATC s service area is divided into five zones representing distinct geographic or usage areas. Within each zone, we compile and assess transmission system needs. PROJECT CLASSIFICATIONS Network and asset renewal projects have targeted in service dates that are designed to address system limitations and condition needs. The network projects are classified into one of three possible categories Planned, Proposed or Provisional, depending upon the stage of the project. Planned Proposed Provisional Status of ATC Studies complete Studies not complete Studies not complete planning activities Application for Application pending None None regulatory approval or order issued Project status Project in construction Project identified Project is not planning phase or under as preferred necessarily the preferred construction alternative alternative Asset renewal projects generally fall into the Provisional or Planned categories. Project is not necessarily the preferred project alternative 2018 10-YEAR ASSESSMENT 11

WOOD JUNEAU LINCOLN ONEIDA MARATHON ADAMS PORTAGE LANGLADE WAUSHARA SHAWANO WAUPACA LAKE NORTH CENTRAL WISCONSIN Zone 1 MARQUETTE GREEN Transmission system characteristics in Zone 1 ATC delivers power in Zone 1 with various transmission facilities including: East west 345 kv line from the Village of Arpin through Stevens Point extending to the Appleton area, 345 kv line extending from Stevens Point, north to Wausau, and east toward Shawano County, 345 kv line extending from Wausau to northeastern Minnesota, 115 kv network in the northern portion of the zone and 138 kv and 69 kv network in the southern portion of the zone. Transmission system limitations in Zone 1 Zone 1 has a few key system performance issues. Low voltages that are a result of potential multiple contingency events will continue to be monitored, high voltages in the northern portion of the zone, and other studies have identified thermal limitations in the northern portion of the zone. The most severe limitations occur during both peak and off peak periods. ELECTRIC SYSTEM OVERVIEW Small increases expected in population, employment Population in Zone 1 is projected to grow at 0.5 percent annually between now and 2027. Employment is projected to grow at 0.9 percent annually between now and 2027. Marathon County is projected to realize the largest increase in population and employment, while Adams County is projected to have the highest growth rate in population and employment. Electricity usage Peak electric demand typically occurs during the summer months, with some winter peaks appearing in the northern portion of the zone. Primary electricity users in Zone 1 include several large paper mills and food processing plants. Electric load is forecasted to grow approximately 0.4 percent annually through 2028. COUNTIES INCLUDED IN ZONE 1 NORTH CENTRAL WISCONSIN Adams Forest (southwestern portion) Fond du Lac (northwestern portion) Green Lake Juneau Langlade Lincoln Marathon Marquette Monroe (eastern portion) Oneida Portage Shawano (western portion) Vernon (eastern portion) Vilas (southern portion) Waupaca Waushara Winnebago (western portion) Wood 12 AMERICAN TRANSMISSION CO.

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WOOD JUNEAU LINCOLN ONEIDA MARATHON ADAMS PORTAGE LANGLADE WAUSHARA SHAWANO WAUPACA NORTH CENTRAL WISCONSIN MARQUETTE GREEN LAKE Zone 1 TRANSMISSION PROJECTS IN ZONE 1 The most notable planned, proposed and provisional network projects and asset renewal projects in Zone 1, along with their projected year of completion and the factors driving the need for the projects, are listed below. PROJECT DESCRIPTION IN SERVICE YEAR NEED DRIVER 1 Planned Projects Wild Rose Harrison 69 kv line (Y 19) partial rebuild 2020 Condition and performance 2 Chaffee Creek Lincoln Pump Station 69 kv line (Y 18) rebuild 2021 Condition and performance 3 Wautoma Chaffee Creek 69 kv line (Y 49) rebuild 2021 Condition and performance Additional projects may be found in the full 10 Year Assessment at atc10yearplan.com. SUBSTATION KEY TRANSMISSION LINE KEY EXISTING TRANSMISSION LINES KEY New substation Supports transmission system expansion Substation modifications Upgrades equipment ratings to avert facility overloads Transformer Supports local growth and improves voltage levels Capacitor bank or reactor Relieves low voltages or high voltages T-D interconnection Supports local growth SYSTEM SOLUTIONS KEY 345-kV transmission line 115-, 138- or 161-kV transmission line 69-kV transmission line Rebuilt 115- or 138-kV transmission line Rebuilt 69-kV transmission line 115- or 138-kV transmission line rating upgrade 69-kV transmission line rating upgrade 69 kv 115 kv 138 kv 161 kv 230 kv 345 kv Lines of proposed projects on the map are for illustrative purposes only and do not reflect actual routes. For information on project status and routes, see atc projects.com. 14 AMERICAN TRANSMISSION CO.

e Saratoga Wood Plainfield Arrowhead (ALTE) Wildrose Plainfield Sherwood Springwater Sand Lake Wild Wild Cottonville Rose Fountain Rose Pump Sawyer Hancock Valley Wautoma Waushara Hancock Pershing Adams Red Granite Coloma!3 3 Wautoma Coloma Silver Friendship Lake Lincoln Pump Richford (ALTE) Spring STA! 2 Chaffee CreekTaylor Lake Friendship Price Adams Line 61 Turtle Grand Marsh Westfield Lake Mckenna Brooks Winnebago Jackson Crawford Seneca Rusk Vernon Monroe County Gays Mills DPC Bell Center Grant AshlandGolden Sands Wautoma Area Portage Chateau Glen Neenah Creek Oxford Clark T Corners Wien SW STA Stratford McMillan Wildwood (MEWD) Mill Creek Hume Rozellville Auburndale Eastom Tomahawk - Skanawan ATC 115kV SW STR Tomahawk Grandfather Falls Grandfather Falls Hydro Cassel Lincoln Pine (WPS) Maine Hilltop (WPS) Sherman St Sunnyvale Kelly Weston SW YD Morrison Ave Gardner Park Cedar Creek Mosinee Paper Mill Kronen Guenther CWEC Dewey Richfield Arpin Northpoint CWEC Iola Lawn Portage Rudolph Iola Rocky Run Hoover Pittsville Vesper Sigel Amherst Jct Whiting Ave CWEC Sannes Arnott Waupaca Manawa Wood Consulated Okray Lakehead West Water Power Plover Vesper Werner West Wisconsin (rrn) Sheridan Werner Outagamie Rapids Coyne St (ALTE) Harrison Hintz North Ellington Wisconsin Rapids Golden Sands 138kV Hartman Creek White Port Edwards Baker St Waupaca Harrison Lake (WE) Vulcan Chem 69kV Apple Hills Hollywood Grant Saratoga Casaloma Butte Des!1 1 Morts Arrowhead Plainfield Northside Plainfield (ALTE) Wildrose M Neevin Sherwood Tayco Melis Wild Rose Winnebago Badger West Springwater Sand Lake Woodenshoe Cottonville Wild Fountain Hancock Rose Pump Valley Winneconne Warrens Waushara Wautoma Mears Corners Hancock Sunset Point Big Pond Wautoma Spring Bowen St Adams Red Granite Omro Coloma Lake Coloma!3 3 Pearl Ave Silver Oshkosh Tunnel City Necedah Omro Cardinal Lake Ellinwood River Run Industrial North Tomah Glass Tomah Dellwood Richford (ALTE) Lincoln Park Friendship Council Creek Pump Berlin Tomah Chaffee Creek Juneau STA!2 2 Fox River Fitzgerald Industrial Pk Houghton Rock Friendship Aviation Timberwolf Camp Douglas Adams Line 61 Turtle Mckenna Grand Marsh Westfield Lake Ripon Dartford DPC Buckhorn Brooks Ind Park Marquette Dorset DPC New Green Lake Corners Lisbon Castle Rock Quincy Northwest Fond Du Lac North Ripon Hilltop Chateau Ripon Fond Du Sadoff Roeder Metomen Lac West Mauston (ALTE) Montello Rosendale Forest Co Eas Winnebago Neenah Creek Green Lake Mauston Glen Montello Mercury SW STA Oxford Brandon Marine Mar Lyndon Mackford Station Markesan Prairie Fairwater South Fond Koch Oil Du Lac Wind G Union Center SW YD DPC Lyndon Endeavor Alto Roslin Oakfield Wonewoc Station Wisconsin Creek Hillsboro Dells Waupun Forward Wisconsin Muni 1 Lakehead Westside Energy Dells Muni 2 Platt Portage Center Buttern Finnegan Dell Creek Kilbourn Loch Mirror Lewiston Cambria North Friesland Reedsburg Zobel Birchwood Hamilton St Randolph Fox Lake Nishan Trienda (ALTE) Staff Portage Ind Pardeeville Didion Reedsburg Fox Hills Portage Sanborn Cambria Artesian Park Randolph Mayville Lake Delton Manley North Rock Springs Sand Wyocena Beaver Dam Spring Brook Island Caledonia Beaver Dam Horicon Baraboo Rio Pumping 3rd St Ind Park Kirkwood (ALTE) Columbia Station Hubbard Loganville SW YD Center St Beaver Dam East Juneau Skillet Creek Calamus (ALTE) Northside Horicon Merrimac Sauk Doylestown South Richland Columbia Beaver Dam Juneau Downtown Poynette Fall River Fountain Prairie Dodge Juneau Industrial Okee Academy Columbus Richland Hustisford Lodi Muni 1 Ha Arlington Center Maple Street Industrial Columbus Butler Ridge Richland Dam Heights Park Lodi Hampden Columbus (ALTE) Brewer Rubicon Pine South River Ninth Street North Madison (ALTE) Troy Sauk City Sauk City Phillips St 345/138 kv North Madison Oak St Dane Dane Deforest Monroe Marquette Harrison Waupaca Iron Hartman Creek 69kV Harrison North 138kV! 1 Montello Montello Waupaca Roeder Green Lake Green Lake SW STA Markesan Marathon Ackley Groenier Venus Antigo Aurora St Birnamwood Metonga 2018 10 YEAR ASSESSMENT Summit Lake (WPS) Langlade Polar Deer Trail Brooks Corners Forest Menominee Middle Vlg Oconto Mountain Silver Cli Wittenberg CWEC Wittenberg White Cla Whitcomb Shawano East Shawano CWEC Tigerton West Shawano Highway 22 Badger Caroline Cloverleaf Marion Belle Plaine Rosholt Clintonville Rosholt CWEC 15 Hills S 2018 10-YEAR ASSESSMENT 15

MICHIGAN S UPPER PENINSULA AND NORTHERN WISCONSIN Zone 2 Transmission system characteristics in Zone 2 ATC delivers power in Zone 2 with various transmission facilities including: Morgan Plains, Plains Arnold, and Arnold Dead River 345 kv lines, Plains Stiles 138 kv double circuit line, Lakota Road Plains 138 kv line, Holmes Old Mead Rd 138 kv line, and 138 kv facilities tying the Upper Peninsula of Michigan to lower Michigan. Transmission system limitations in Zone 2 There are a number of transmission system performance issues in Zone 2, including limited ability to import or export power, generator instability, overloaded lines and equipment, low and high system voltages and chronic limitations to transmission service. Primary drivers of these issues include a mismatch of load to generation in the Upper Peninsula and aging facilities in poor or deteriorated condition. In addition, other ongoing studies, including northern area studies performed by ATC and MISO, have identified several voltage and thermal limitations. The most severe limitations occur during both peak and off peak periods. ELECTRIC SYSTEM OVERVIEW Small increases expected in population, employment Population in Zone 2 is projected to grow about 0.2 percent annually between now and 2027, and employment is expected to grow about 0.8 percent each year in the same time period. Marquette County (Michigan) is projected to realize the largest increase in population and employment. Florence County (Wisconsin) is projected to have the highest growth rate in population while Keweenaw County (Michigan) is projected to have the highest growth rate in employment. Electricity usage Zone 2 typically experiences peak electric demand during the winter months. Ore mining and paper mills are the largest electricity users in the zone. In the recent past, there have been some load reductions in Zone 2. From these reduced levels, electric load is forecasted to increase by 0.4 percent annually through 2028. Also, locally generated electricity is declining in the area with smaller, coal fired generators most at risk. This includes generation owned by industry, municipalities and utilities. COUNTIES INCLUDED IN ZONE 2 MICHIGAN S UPPER PENINSULA AND NORTHERN WISCONSIN Alger, Mich. Baraga, Mich. Chippewa, Mich. Delta, Mich. Dickinson, Mich. Florence, Wis. Forest, Wis. (northern portion) Gogebic, Mich. (eastern portion) Houghton, Mich. Iron, Mich. Keweenaw, Mich. Luce, Mich. Mackinac, Mich. Marinette, Wis. (northern portion) Marquette, Mich. Menominee, Mich. (northern portion) Ontonagon, Mich. (eastern portion) Schoolcraft, Mich. Vilas, Wis. (northern portion) 16 AMERICAN TRANSMISSION CO.

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MICHIGAN S UPPER PENINSULA AND NORTHERN WISCONSIN Zone 2 TRANSMISSION PROJECTS IN ZONE 2 The most notable planned, proposed and provisional network projects and asset renewal projects in Zone 2, along with their projected year of completion and the factors driving the need for the projects, are listed on page 19. L a k e S u p erior UPSCO Ontonagon Winona Osceola Boston Elevation St MTU Atlantic Henry St. Portage (UPPCO) (UPPCO) Toivola Donken Houghton Keweenaw Keweenaw SYSTEM SOLUTIONS KEY SUBSTATION KEY New substation Supports transmission system expansion Substation modifications Upgrades equipment ratings to avert facility overloads Transformer Supports local growth and improves voltage levels Capacitor bank Relieves low voltages or high voltages T-D interconnection Supports local growth TRANSMISSION LINE KEY 345-kV transmission line 115-, 138- or 161-kV transmission line 69-kV transmission line Transmission line voltage conversion Rebuilt 115- or 138-kV transmission line Rebuilt 69-kV transmission line 115- or 138-kV transmission line rating upgrade 69-kV transmission line rating upgrade EXISTING TRANSMISSION LINES KEY 69 kv 115 kv 138 kv 161 kv 230 kv 345 kv White Pine Mine hite Vlg gebic Eagle River St Germain Cranberry Clear Lake (WPS) Rhinelander Paper Hodag Highway Eight om Skanawan SW STR oln ine Vilas Pine (WPS) herman St Kelly Morrison Ave Cedar Creek Lake Mine Rockland Mass (UPP) Victoria Hy Ontonagon Land O Lakes Oneida Ackley Marathon Lakota Rd Conover Bruce Crossing Watersmeet Venus 6 Twin Lake Three Lakes Summit Lake (WPS) Langlade Polar Antigo Aurora St Brooks Birnamwood Corners Wittenberg CWEC Wittenberg Whitcomb Metonga Deer Trail Forest Shawano M-38 JH Warden L'anse Baraga Vlg 3 Lakehead Iron River Homer Road Iron Grove Menominee Middle Vlg West Shawano Iron Baraga Florence Crystal Falls Sagola Felch Peavy Randville Nordic Mountain Falls Hy Brule SW STA Michigamme Aspen Falls Hy Twin Falls Florence SW STA Pine Hy Bass Lake Armory Plains Norway Grede Foundries Aragon Kingsford Champion Bluff Metals Niagra View Paper Of Wisconsin Goodman White Clay Way Plant Greenstone Humboldt Mine Perch Lake Lena Oconto Falls Stiles SW STA Pioneer (WPS) Dead River Presq (WE) Isle S Big Bay Marqu North Diese Lake Barnum Huron National Empire Mine Tilden Mich Transmitter Facility Nathan Sawyer Lumber K I Gwinn Forsyt Arnold Watso Watson Powers Amberg White Chalk Hill Hy Benson Lake Rapids Hy Holmes Silver Cliff Marinette Fox Hills SW Grand STA Rapids Hy Ingalls Caldron Falls Hy High Falls Hy Sandstone Thunder Rapids Hy Mountain Crivitz Bay De Noc 30th Ave Pound Peshtigo Sherwood Oconto 5 Marquette Dickinson 2 4 Menomin Sawye SW STA Redwood Industria Brusbay 18 AMERICAN TRANSMISSION CO.

PROJECT DESCRIPTION IN SERVICE YEAR NEED DRIVER 1 2 3 4 Planned Projects Munising Blaney Park 69 kv line (Inland) rebuild 2019 Condition and performance J703: Huron Substation, new G T interconnection 2019 G T interconnection J704: Silver River Substation, new G T interconnection 2019 G T interconnection Plains Arnold 138 kv uprate 2019 Network integration transmission service request 5 Proposed Project J711 Silver River Substation, network upgrades 2020 G T interconnection 6 Provisional Projects Lakota Winona 138 kv conversion 2021 Overloads and low voltages 7 Mackinac McGulpin 138 kv submarine cables (9901, 9903), replacement 2021 Condition Additional projects may be found in the full 10 Year Assessment at atc10yearplan.com. ue W YD ette l Sawyer h Timber Munising Products Chatham Alger Forest Lake Shingleton Hiawatha (AD-REA) Alger 1 Schoolcraft Magazine Portage St Hy 3 Mile Sault Pine Grove Luce Brimley Dafter 9 Mile SW STA Raco Eckerman Newberry Vlg Hulbert Seney (UPPCO) Lou Pac Newberry Hulbert Chippewa Tone Seney Newberry Kincheloe (AD-REA) Correctional Trout SW STA Facility Pickford Lake (CEC) Rudyard Pickford Pine River Rockview Engadine Lakehead Rexton Frank Mackinac Talentino Gould City Limeston Hiawatha Lakehead SW STA Curtis Goetzville (ESE) Naubinway Mich Frank Detour Gould City Brevort Blaney Limestone Talentino SW STA Park Quarry Mich Limestone SW STA Loading Dock n Lakehead Indian Lake Perkins Valley (ESE) Rapid Delta Evergreen River Garden Manistique Glen Jenks Mackinac Corners St Ignace Cornell-UP Mackinac Converter Masonville Straits (UPPCO) Chandler Gladstone McGulpin Old Mead Road 7 Mead Paper North Bluff Mead Pump Delta (UPPCO) Escanaba Steam Plant Harris West Side Emmet Cheboygan ee Door Dunn Rd r Michigan St Canal l Sister Bay Egg Harbor L a k e M i c higan Leelanau Charlevoix Antrim Kalkaska Alpena Lines of proposed Montmorency projects on the Otsego map are for illustrative purposes only and do not reflect actual routes. For information on project status and routes, see atc projects.com. Crawford Oscoda Presque Isle Alcona 2018 10-YEAR ASSESSMENT 19

SOUTH CENTRAL/SOUTHWEST WISCONSIN AND NORTH CENTRAL ILLINOIS Zone 3 Transmission system characteristics in Zone 3 ATC delivers power in Zone 3 with various transmission facilities including: Columbia North Madison 345 kv lines, Columbia Rockdale 345 kv line, Paddock Rockdale 345 kv line, Paddock Wempletown 345 kv line, Rockdale Wempletown 345 kv line, Rockdale Cardinal 345 kv line, and 138 kv facilities from Nelson Dewey, around the Madison area, and in the northwest and southeast portions of Zone 3. Transmission system limitations in Zone 3 ELECTRIC SYSTEM OVERVIEW Increases expected in population, employment Population in Zone 3 is projected to grow about 0.8 percent annually between now and 2027, and employment is projected to grow about 1.3 percent each year for the same time period. Dane County is projected to realize the largest increase in population and employment. Dane County is also projected to have the highest growth rate in population and employment. Electricity usage Electric load is forecasted to grow approximately 0.7 percent annually through 2028 in Zone 3. In our analysis of Zone 3, we identified a number of transmission facility overloads. These overloads are due to new generation in the Janesville and Darlington areas. In addition, other emerging issues resulting in facility overloads include steady growth in certain areas and different generation dispatches. The most severe limitations occur during both peak and off peak periods. COUNTIES INCLUDED IN ZONE 3 SOUTH CENTRAL/SOUTHWEST WISCONSIN AND NORTH CENTRAL ILLINOIS Columbia Crawford (southern portion) Dane Dodge Grant Green Iowa Lafayette Jefferson Richland Rock Sauk Walworth Winnebago, Ill. (northern portion) 20 AMERICAN TRANSMISSION CO.

2018 10 YEAR ASSESSMENT 21

SOUTH CENTRAL/SOUTHWEST WISCONSIN AND NORTH CENTRAL ILLINOIS Zone 3 TRANSMISSION PROJECTS IN ZONE 3 The most notable planned, proposed and provisional network projects and asset renewal projects in Zone 3, along with their projected year of completion and the factors driving the need for the projects, are listed on page 23. Briggs Road Sauk La Crosse Monroe County Monroe Timberwolf Industrial Pk Dorset Corners Vienna Sun Prairie Waunakee Business Park Mazomanie Industrial Token Creek Division Street Industrial Park Mazomanie Yahara River Colorado Bird St Centennial Wick Drive Park Highway 151 Waunakee SW South STA Sun American Prairie Black Earth Westport Dane Huiskamp Burke Stage Coach SW STA Walnut GIS! Sycamore Reiner Rd Pheasant SW YD West Branch Mendota Gaston Rd Ruskin East Towne Middleton Walnut Royster Sprecher Cross Plains Gateway (MGE) 9 Blount Cottage Grove Cardinal Blackhawk (MGE) Pflaum Pleasant View AGA Gas East Campus Wingra Femrite Tokay McFarland Wally Road Syene Nine! Timberlane West Towne Femrite East 10 Fitchburg 138/69 kv Lincoln St Springs Mount Horeb Colladay Cross Country Oak Ridge Point Kegonsa Verona Vernon! North 8 Stoughton Sun Valley Oregon Iowa Madison Area Hillsboro Camp Douglas DPC New Lisbon Union Center West Mau Wonewoc Jun SYSTEM SOLUTIONS KEY SUBSTATION KEY New substation Supports transmission system expansion Substation modifications Upgrades equipment ratings to avert facility overloads Transformer Supports local growth and improves voltage levels Capacitor bank Relieves low voltages or high voltages T-D interconnection Supports local growth TRANSMISSION LINE KEY 345-kV transmission line 115-, 138- or 161-kV transmission line 69-kV transmission line Rebuilt 115- or 138-kV transmission line Rebuilt 69-kV transmission line 115- or 138-kV transmission line rating upgrade 69-kV transmission line rating upgrade EXISTING TRANSMISSION LINES KEY 69 kv 115 kv 138 kv 161 kv 230 kv 345 kv Lines of proposed projects on the map are for illustrative purposes only and do not reflect actual routes. For information on project status and routes, see atc projects.com. Allamakee Clayton Brisbois Nelson Dewey SW YD Seneca Hillside DPC Gran Grae Gran Grae La Pointe Prairie Du Chien Glen Haven Cassville Crawford DPC Stoneman Wauzeka Bloomington Gays Mills DPC Bell Center Grant Boscobel Muni Boscobel Boscobel Boscobel Muni Eastside Lancaster Distribution Potosi Lancaster Blue River 4 Pioneer(ALTE) Hillman Richland Muscoda Hill Valley Brewer Elmo Richland Center Muscoda Industrial Sub Eden Cuba City Pine River (ALTE) Rewey Richland Avoca Belmont 9 Falcon Lone Rock Iowa Lands End Mineral Point Red Bird Kieler Cuba City South Benton Shullsburg DPC Shullsburg to Dubuque County area Miners Delaware Dubuque 22 AMERICAN TRANSMISSION CO.

Wyoming Valley Dodgeville Rock Branch Darlington 1 2 3 4 5 6 Spring Green Lafayette DPC Gratiot PROJECT DESCRIPTION IN SERVICE YEAR NEED DRIVER Planned Projects Badger Coulee: Briggs Rd North Madison Cardinal 345 kv line construction Lone Rock Friendship Boscobel Pump STA 69 kv line (Y 124) rebuild 2019 Condition and performance Mckenna Grand Marsh Westfield Lake Portage Staff North Randolph 138 kv lines (X 6), (X 98), rebuild 2020 Condition Dartford Ripon and performance Ind Park Adams Brooks Quincy Sheepskin Stoughton 69 kv line (Y 12) rebuild Green Lake 2021 Condition and performance Troy Arena Wiota Sauk New Hollandale Mazomanie Industrial Wick Drive Blanchardville Jennings Rd SW STA Mazomanie Black Earth Stage Coach SW STA Cross Plains Browntown Forward Dam Heights Wally Road Mount Horeb Dane Green Idle Hour South Monroe Lodi Industrial Park Pleasant View New Glarus Okee Monticello (ALTE) Lodi North Monroe North Madison 345/138 kv Tokay Blacksmith Walnut GIS Syene Brodhead Spring Grove Poynette Blount AGA Gas Wingra Pflaum Femrite Albany (ALTE) Nine Springs Brooklyn Brodhead SW STA REC Orfordville Hampden McFarland Stoughton South Union Townline Vinburn Kegonsa REC Newark Cottage Grove North Stoughton Stoughton Stoughton East Footville Bass Creek Fall River Fountain Prairie Academy Columbus Maple Street (ALTE) Dana Corp Paddock Columbus South Christiana Sheepskin Lakehead Waterloo Rock McCue Boxelder London Russell Traxler Viking Columbus Muni 1 Rockdale Stony Brook Milton Lawns Venture Tripp Rd REC LaPrairie Rock River Turtle Marine Lakehead Cambridge LaMar Sunrise Scot Forge 2 Crawfish River Scot Forge 1 Dodge Jefferson Colley Rd REC Clinton East Beloit Shirland Park Ave Ave REC East Rockton Shaw Fort Atkinson REC Red Hawk Juneau Industrial Jefferson REC Bradford University (WE) Concord SW YD Walworth Sharon Delavan Bluff Creek Hustisford Bristol (ALTE) West Southwest Delavan Williams Darien Bay Brick Church Walworth Butler Ridge Rubicon Cooney Sugar Creek Elkhorn Fond Du Lac Castle Rock DPC Buckhorn 7 Northwest Ripon North Hilltop Chateau Ripon Fond Du Roeder Metomen Lac Sadoff ston (ALTE) Proposed Projects Montello Rosendale Forest Co East Scott St Ledgeview Mauston Winnebago Neenah Creek eau Marquette Green Lake Macy St 8 Northern Lights Substation, Glen new T D interconnection 2020 T D interconnection SW STA Mercury Marine Ohmstead Oxford Brandon Willow Lawn Rienzi Road 9 Cardinal Hickory Creek 345 kv line construction 2023 Reliability, economics and public Martin policy Mackford Rd South Fond Markesan Prairie Fairwater Koch Oil Oakfield Du Lac SW YD Lyndon Provisional Project Station Forward Endeavor Alto Roslin Energy Creekview 10 Cardinal DPC Lyndon Blount 138 kv line construction 2029 Overloads and low voltages Station Wisconsin Center Dells Waupun Wisconsin Muni 1 Lakehead Additional Dells Muni projects 2 Platt may be found in the full 10 Year Assessment at atc10yearplan.com. Waupun Portage Butternut Finnegan Kilbourn Westside Dell Creek Loch Mirror Lewiston Cambria Zobel Hamilton St Staff Friesland Reedsburg Birchwood North Fox Lake Trienda Nishan Randolph (ALTE) Portage Ind Pardeeville Sanborn Cambria Didion Randolph Reedsburg Artesian Fox Hills Portage Park Mayville Lake Delton 6 North Rock Springs Manley Sand Beaver Dam 1 Horicon Spring Brook Rio Pumping Island Beaver Dam Beaver Caledonia Ind Baraboo Columbia Wyocena Station 3rd St Dam East Park Kirkwood (ALTE) SW YD Center St Hubbard Loganville Skillet Creek (ALTE) Columbia Juneau Calamus Northside Horicon Merrimac Doylestown South Beaver Dam Hooterville Sauk City Phillips St East Lincoln St Ninth Street Sauk City Oak St Timberlane Dane West Towne North Madison Cross Country Fitchburg Verona Belleville Oak Ridge Brodhead South Arlington Vienna Sun Prairie Business Park Division Yahara River Street Centennial Park Bird St Token Creek South Waunakee SW Burke Sun Prairie STA American Highway 151 Westport Sycamore Reiner Rd Pheasant SW YD West Branch East Towne Ruskin Middleton Gaston Rd Walnut Royster Cardinal (MGE) Sprecher Monroe Central Sun Valley Brodhead North Colladay Point Oregon Deforest Evansville Muni Brodhead Central Orfordville REC Center REC Fulton Cambridge Saunders Creek REC Harmony Tyranena Janesville General SW YD Whitewater Lakehead Delavan Juneau Downtown Lakehead Pipeline North Lake Geneva Lake Geneva Zenda Cobblestone Hartford Summit Waukesha Mukwonago St Lawrence Washington Bark River Cottonwood (WE) South Lake Geneva Katzenberg Cedar Ridge Wind Generation Arthur Road Merrill Hills Burlington Waukesha Air Liquide Balsam New Holstein SW STA Houghton Rock Adams Line 61 Spring Valley North Lake Geneva 138 kv line construction 2019 Overloads and low voltages, provide network service Turtle Cypress SW YD Esker View 3 8 10 I L L I NOIS Stoughton West 7 2 Lakehead Waterloo 2 Edgerton Business Park 2018 Reliability, economics and public policy J390: Kittyhawk Substation, new G T interconnection 2019 G T interconnection J395: Darlington North Monroe 138 kv line (X 49), Uprate 2019 G T interconnection Lakehead Delavan T2 Tiger 23 5 Auburn Glacier Sussex Edgewood Barton Pleasant Valley Racine Kettle Morraine (ALTE) Maple (WE) Tamarack Duplainville Tichigan Mill Rd Kenosha Twin Lakes (ALTE) Richmond Road Germantown SW YD 2018 10 YEAR 10-YEAR ASSESSMENT 23

NORTHEAST WISCONSIN Zone 4 Transmission system characteristics in Zone 4 ATC delivers power in Zone 4 with various transmission facilities including: four 345 kv lines extending from the Point Beach Nuclear Plant, two 345 kv lines extending from the Edgewater Power Plant to South Fond du Lac and Cedarsauk, two additional 345 kv lines connecting the South Fond du Lac Power Plant to Columbia and Fitzgerald, four 345 kv lines connecting the Gardner Park, Werner West, Morgan, and Plains Substations, four 345 kv lines from North Appleton to Kewaunee, Fox River, Werner West and Fitzgerald, and a 138 kv network throughout the zone. Transmission system limitations in Zone 4 In our analysis of Zone 4, we found high voltages in Calumet County and impending low voltages in Brown County. In addition, other ongoing studies have identified several voltage and thermal limitations. The most severe limitations occur during both peak and off peak periods. ELECTRIC SYSTEM OVERVIEW Increases expected in population, employment Population in Zone 4 is projected to grow at 0.6 percent annually between now and 2027. Employment is projected to grow at 1.0 percent annually between now and 2027. Brown County is projected to realize the largest increase in population and employment. Calumet County is projected to have the highest growth rate in population and Sheboygan County is projected to have the highest growth rate in employment. Electricity usage Peak electric demand typically occurs during the summer months, although the northern portion of Zone 4 typically experiences nearly equal summer and winter peaks. Paper mills and foundries in and around the Green Bay and Appleton metropolitan areas are some of the largest electricity users in the zone. Electric load is forecasted to grow at approximately 0.3 percent annually through 2028. Also, locally generated electricity is declining in the area with smaller, coal fired generators most at risk. This includes generation owned by industries, municipalities and utilities. Several area projects are related to the underlying condition and performance of assets in Zone 4. COUNTIES INCLUDED IN ZONE 4 NORTHEAST WISCONSIN Brown Calumet Dodge (northeastern corner) Door Fond du Lac (eastern portion) Kewaunee Manitowoc Marinette (southern portion) Menominee, Mich. (southern portion) Menominee, Wis. Oconto Outagamie Shawano (eastern portion) Sheboygan Winnebago (eastern portion) 24 AMERICAN TRANSMISSION CO.

2018 10-YEAR ASSESSMENT 25

NORTHEAST WISCONSIN Zone 4 TRANSMISSION PROJECTS IN ZONE 4 The most notable planned, proposed and provisional network projects and asset renewal projects in Zone 4, along with their projected year of completion and the factors driving the need for the projects, are listed below. PROJECT DESCRIPTION IN SERVICE YEAR NEED DRIVER 1 Planned Projects Bay Lake: North Appleton Morgan 345 kv and 138 kv line construction 2018 Overloads and low voltages 2 3 4 Cedar Ridge Wind Mullet River 138 kv line (X 97) rebuild 2020 Condition and performance Edgewater SS, 345 kv bus reconfiguration 2020 Condition and performance Goodman Caldron Falls 69 kv line (J 88) rebuild 2020 Condition and performance 5 Butte des Morts Sunset Point 138 kv lines (40321), (80952), (A 79), (MCRG21) rebuild 2021 Condition and performance 6 7 8 9 10 Finger Rd Canal 69 kv line (J 10) rebuild 2021 Condition and performance Ogden St. Bayshore 69 kv line construction 2021 Provide network service Hwy V Oak St 69 kv line (Z 26) rebuild 2022 Condition and performance Proposed Projects Bayport area Pioneer, rebuild as double circuit 138 kv 2021 Condition, performance and provide network service Pioneer Crivitz (E 83/B 2), retire 69 kv and 2022 Condition, performance, reconfigure load to 138 kv and provide network service Additional projects may be found in the full 10 Year Assessment at atc10yearplan.com. New substation Supports transmission system expansion Substation modifications Upgrades equipment ratings to avert facility overloads Transformer Supports local growth and improves voltage levels Capacitor bank or reactor Relieves low voltages or high voltages T-D interconnection Supports local growth SYSTEM SOLUTIONS KEY SUBSTATION KEY TRANSMISSION LINE KEY EXISTING TRANSMISSION LINES KEY 345-kV transmission line 115-, 138- or 161-kV transmission line 69-kV transmission line Transmission line voltage conversion Rebuilt 115- or 138-kV transmission line Rebuilt 69-kV transmission line 115- or 138-kV transmission line rating upgrade 69-kV transmission line rating upgrade 69 kv 115 kv 138 kv 161 kv 230 kv 345 kv 26 AMERICAN TRANSMISSION CO.

Metonga Forest Amberg Benson Lake Chalk Hill Hy White Rapids Hy Holmes Menominee Fox Hills Silver Cliff SW STA 4 Caldron Falls Hy Grand Rapids Hy Ingalls Langlade High Falls Hy Thunder High Falls Hy Marinette Sandstone Rapids Hy r Brooks Corners Polar Deer Trail CWEC Tigerton EC Iola Harrison North 138kV Waupaca rrison 9kV Green Lake SW STA Markesan Fountain Valley Waushara d Granite North Friesland Randolph a Randolph Didion Manawa Waupaca Green Lake mbia Shawano White Lake (WE) River Run Fox River Berlin Marion Ripon Dartford Northwest Ind Park Ripon Ripon Mackford Prairie Fox Lake (ALTE) Caroline Fairwater Werner West Hintz Werner Metomen Middle Vlg Brandon Alto Menominee West Shawano East Shawano Highway 22 Badger Cloverleaf Belle Plaine Clintonville Winnebago Winneconne Rosendale Woodenshoe White Clay Lawn Rd Lawn Rd Casaloma Maes Kaukauna Central Butte Des Combined City Morts Locks Limits Lake Park Northside Meadows Neevin Tayco Melissa Mears Corners Omro Sunset Point Industrial Bowen St Omro Park Pearl Ave Oshkosh Ellinwood 12th Progress Fitzgerald Waupun Waupun Westside Dodge Koch Oil Aviation Ellington 5 North Fond Du Lac Sadoff Forest Co East Scott St Ledgeview Macy St Hickory St Mercury Marine Ohmstead Cedar Ridge Willow Lawn Rienzi Wind Generation Road Martin Rd South Oakfield Fond Du Lac SW YD Forward Energy Creekview Center Mayville Mountain Outagamie Butternut 1 North Appleton Apple Hills Oconto Fond Du Lac Morgan Auburn Falls Fox River SW YRD Kaukauna North Calumet Cypress SW YD Pound Pioneer (W PS) Crivitz Stiles SW STA Little Suamico Sobieski Forest Ryan St Junction Glenview Iron Foundry Brillion Iron Works Gravesville Suamico Ford Drive Tecumseh Rd New Holstein New Roosevelt Holstein SW STA Oconto Bayport Maplewood SW STA Howard Pulliam SW YD Velp Ave Mason St 7th St Preble Liberty St Finger Rd SW STA Highway V Ontario Ashland Ave Glory Rd Oak St De Pere Red Maple Rockland (W PS) Lost Dauphin Kettle Morraine (ALTE) 2 Washington Lena 8 Greenleaf 10 9 Esker View Brown Wesmark Branch River St Nazianz Howards Grove Elkhart Lake Plymouth Sub 4 Erdman North Gate Northside Plymouth Plymouth Sub 3 (sfm) 32nd St Muncipal (ALTE) 20th St Riverside (ALTE) Mullet River Sheboygan Bemis Falls Energy North Nicolet Edgewater SW YD Center SW YD Mullet River Monroe St South Sheboygan Falls Lyndon Sheboygan Fredonia Holland Ozaukee Bay De Noc Menominee 30th Ave Wells Scott Paper Co St Ogden St West Marinette Peshtigo SW YD Sherwood L a k e M i c higan Dyckesville Kellnersville Manitowoc Luxemburg Rosiere Kewaunee Booster Brusbay East Krok Kewaunee SW YD Apollo Point Beach SW YD Mishicot Columbus St Shoto Mirro Northeast Rapids Revere Dr Manrap Lakefront SW YD Custer Mpu Plant Dewey 3 7 6 Sawyer Michigan St SW STA Redwood First Ave Industrial Canal Algoma Algoma City Algoma South Barnett Beardsley St Door Dunn Rd Mason St Bayport SW STA Egg Harbor Howard Sister Bay Green Bay Area Velp Ave Pulliam SW YD Tower Dr Danz James St Ave SW Van Buren St STA Eastman Ave Henry St Brown 7th St (WPS) Liberty St Preble South Broadway Finger Rd Potts Avenue SW STA Highway V! 8 Glory Ashland Ave Road North Bluestone Glory Rd De Pere Oak St De Pere Nicolet Paper Co Mystery Hills Lines of proposed projects on the map are for illustrative purposes only and do not reflect actual routes. For information on project status and routes, see atc projects.com. # 2018 10 YEAR ASSESSMENT 27

SOUTHEAST WISCONSIN Zone 5 Transmission system characteristics in Zone 5 ATC delivers power in Zone 5 with various transmission facilities including: the southern portion of 345 kv lines from Point Beach and Edgewater, the Saukville, Arcadian, Granville, Oak Creek, and Racine 345 /138 kv substations, the transmission lines emanating from the Oak Creek power plant, 230 kv facilities near Milwaukee, and a significant 138 kv network in the Milwaukee area, a portion of which is underground. Transmission system limitations in Zone 5 Transmission system performance issues in Zone 5 include heavy market flows to and from the south, resulting in high 345 kv and 138 kv line loadings and the need to monitor potential multiple contingency conditions. ELECTRIC SYSTEM OVERVIEW Increases expected in population, employment Population in Zone 5 is projected to grow 0.5 percent annually between now and 2027, and employment is projected to grow 1.1 percent in the same time period. Waukesha County is projected to realize the largest increase in both population and employment. Waukesha County is also projected to have the highest growth rate in employment while Ozaukee County is projected to have the highest growth rate in population. Electricity usage Peak electric demand typically occurs during the summer months. Large industrial loads in the Milwaukee metropolitan area are among the largest electricity users in the zone. Electric load is forecasted to grow approximately 0.7 percent annually through 2028. COUNTIES INCLUDED IN ZONE 5 SOUTHEAST WISCONSIN Kenosha Milwaukee Ozaukee Racine Washington Waukesha 28 AMERICAN TRANSMISSION CO.

AMERICAN TRANSMISSION CO. 2016 10 YEAR ASSESSMENT 2018 10-YEAR ASSESSMENT 29