HISTORY OF CONSTRUCTION W.H. Sammis Coal Plant North and South Ponds Stratton, Ohio

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1 Prepared for: FirstEnergy Generation, LLC 76 South Main St Akron, OH HISTORY OF CONSTRUCTION Stratton, Ohio Prepared by: Wincopin Circle, Floor 4 Columbia, Maryland October 2016 pdf 1 of 24

2 TABLE OF CONTENTS 1. INTRODUCTION Purpose Site Location Impoundment Description CCR RULE REQUIREMENTS FOR HISTORY OF CONSTRUCTION (C) HISTORY OF CONSTRUCTION Owner and Unit Identification Unit Location on USGS Map Purpose of the CCR Unit Name and Size of the Watershed Description of Foundation and Abutment Materials Overview Regional Geology Foundation Materials Abutment Materials Description of the Materials, Methods, and Dates of Construction Overview Initial Construction Circa Pond Modifications Circa Pond Plans Circa Pond Modification and Discharge Piping Upgrades Circa Pond Outlet Modification and Discharge Piping Upgrades Drawings Type, Purpose, and Location of Instrumentation Area-Capacity Curves Spillway Description and Calculations Construction Specifications and Provisions for Operations and Maintenance Record of Structural Instability REFERENCES...13 ME1292/257.73(c)(1) History of Construction FNL i October 2016 pdf 2 of 24

3 LIST OF FIGURES Figure 1 Site Location Map: North and South Ponds Figure 2 Site Plan: North and South Ponds LIST OF APPENDICES Appendix A Drawing Appendix B Stage-Storage Curves ME1292/257.73(c)(1) History of Construction FNL ii October 2016 pdf 3 of 24

4 1. INTRODUCTION 1.1 Purpose Geosyntec Consultants (Geosyntec) has prepared this History of Construction Report for FirstEnergy Generation, LLC (FirstEnergy) for the existing W.H. Sammis Coal Plant North and South Ponds (North and South Ponds) in Stratton, Ohio. This report is prepared for compliance with the Federal Coal Combustion Residuals (CCR) Rule, 40 CFR 257. This Regulation is referred to herein as the CCR Rule. In this History of Construction Report, the requirements of (c) are addressed. 1.2 Site Location The North and South Ponds are located at the W.H. Sammis Plant (Plant) in Stratton, Jefferson County, Ohio. The Plant can be found on the United States Geological Survey (USGS) 7.5-minute topographic map for the Wellsville, Ohio Quadrangle (Figure 1). The Plant is located adjacent to Ohio State Route 7 and the Ohio River. The North and South Ponds are located in the southeast quadrant of the generating facility. 1.3 Impoundment Description The North and South Ponds were initially constructed circa 1959, modified in 1971, and further modified into their current configuration in The ponds are used for temporary storage of bottom ash (i.e., CCR) and treatment of other wastewater produced by plant operations. Each pond is typically in service for approximately six to nine months (depending on the volume of CCR and waste produced by the Plant s generating units) before being taken out of service for removal of accumulated CCR s, at which time the adjacent pond is used for temporary storage of CCR and plant wastewater. General maintenance activities are performed when a pond is out of service. When in service, water and bottom ash enter one corner of the North or South Pond and flows around the perimeter to the opposite corner where the water discharges through a concrete outlet riser. The North Pond outlet riser is fitted with a weir plate that governs the pond elevation. The water elevation in the South Pond is, historically and currently, controlled by timber stop logs and an inline valve. As part of planned upgrades to the South Pond hydraulic structures, the outlet riser is to be fitted with a weir plate to control the water elevation. The modification is expected to occur at a future time when the Pond is removed from service for regular cleaning and maintenance. Water passes from the base of the outlet risers through buried conveyance pipes and enters into a storm drain buried along the northern perimeter of the North Pond, which discharges at an NPDES permitted outfall. The storm drain pipe is part of a network which passes run-on water from the west side of the Plant to the Ohio River. The storm drain network terminates at an endwall structure located adjacent to State Route 7 at the northeast corner of the North Pond. The discharge immediately enters a concrete box culvert beneath the road and enters into the Ohio River at the upstream side of the New Cumberland Lock and Dam. A site plan identifying the primary features of the North and South Ponds is presented on Figure 2. ME1292/257.73(c)(1) History of Construction FNL 1 October 2016 pdf 4 of 24

5 The culvert outlet at the endwall of the storm drain network, which discharges the combined stormwater and CCR impoundment effluent, is a permitted discharge point under the Ohio Environmental Protection Agency (OEPA), National Pollutant Discharge Elimination System (NPDES), Permit No. OH The North Pond is regulated by the Ohio Department of Natural Resources (ODNR) Dam Safety Program as a Class II Dam, File No ME1292/257.73(c)(1) History of Construction FNL 2 October 2016 pdf 5 of 24

6 2. CCR RULE REQUIREMENTS FOR HISTORY OF CONSTRUCTION (c) The CCR Rule requires the owner or operator of an existing CCR unit to compile a history of construction containing, to the extent feasible, the information specified by the CCR Rule. The CCR Rule states that, for existing units, the history of construction is required to include the specified information only to the extent that it is readily available and that no new information should be generated as part of the history of construction. Part 3 of this document presents the documentation required for compliance with (c). The table below summarizes the information to be included in the history of construction and identifies the location in this report where the information is provided. RULE SECTION RULE REQUIREMENT LOCATION WHERE ADDRESSED IN DOCUMENT (c)(1)(i) Owner and Unit Identification Section (c)(1)(ii) Unit Location on USGS Map Section (c)(1)(iii) Purpose of the CCR Unit Section (c)(1)(iv) Name and Size of the Watershed Section (c)(1)(v) (c)(1)(vi) Description of Foundation and Abutment Materials Description of the Materials, Methods, and Timeframe of Construction Section 3.5 Section (c)(1)(vii) Drawings Section (c)(1)(viii) Instrumentation Section (c)(1)(ix) Area Capacity Curves Section (c)(1)(x) Spillway Description and Calculations Section (c)(1)(xi) Construction Specifications and Provisions for Operations and Maintenance Section (c)(1)(xii) Record of Any Structural Instability Section 3.12 ME1292/257.73(c)(1) History of Construction FNL 3 October 2016 pdf 6 of 24

7 3. HISTORY OF CONSTRUCTION 3.1 Owner and Unit Identification The North and South Ponds are owned and operated by FirstEnergy Generation, LLC located at 76 S. Main Street, Akron, Ohio W.H. Sammis Coal Plant is located at State Route 7, Stratton, Ohio The units are commonly referred to as the North and South Ponds, respectively. The North Pond, which is regulated by the ODNR Dam Safety Program, is identified by the ODNR as the Sammis Station North Bottom Ash Pond with File No Unit Location on USGS Map The ponds are located in Stratton, Jefferson County, Ohio. A 7.5-minute United States Geological Survey (USGS) map of the Wellsville Quadrangle showing the location of the ponds is provided as Figure Purpose of the CCR Unit The North and South Ponds are used for temporary storage of CCR bottom ash and treatment of process wastewater produced as byproducts of the coal-fired electric generating units of the W.H. Sammis Coal Plant. 3.4 Name and Size of the Watershed The units are located in the Upper Ohio watershed (ID ) 1. The North and South ponds are each located on the right bank of the Ohio River, above the FEMA 100-yr flood elevation, and directly adjacent to the upstream side of the New Cumberland Lock and Dam. Despite the close proximity of the units to the Ohio River, historic flood information reveals that river elevations have only reached the toe of the embankments two times in the last 74 years 2. Therefore, the Ohio River is not considered to be a significant influence on the operation or stability of the North and South Ponds. The contributing drainage area to the North and South Ponds includes only the immediate industrial areas of the Plant surrounding the ponds. The contributing drainage areas to the North and South Ponds, including the surface area of the ponds, are approximately 7.3 acres 6.5 acres, respectively ME1292/257.73(c)(1) History of Construction FNL 4 October 2016 pdf 7 of 24

8 3.5 Description of Foundation and Abutment Materials Overview The North and South Ponds are formed by multiple upground embankments abutted to placed fill soil. The North Pond is formed by upground embankments to the east and south with its west and north embankment formed by at-grade fill material. The South pond is formed by upground embankments to the north (shared with the North pond), east, and south with its west embankment formed by at-grade native or fill material. Geotechnical investigations indicate that fill placement within the pond footprints extends from ground surface down to approximate elevations between 660 and 670 f (L.R. Kimball, 2007; Geosyntec, 2016a). The remainder of this section presents documentation of the regional geology and location-specific information pertaining to the foundation and abutment soils Regional Geology Details of the regional geology are obtained from the map of Ohio Bedrock Geology (Ohio Division of Geological Survey, 2006). The bedrock in Jefferson County is sedimentary rock laid down during the Pennsylvanian and Permian periods and the rock strata are not horizontal or regularly sloping. Shale, siltstone, and sandstone are the most common types of bedrock to outcrop. The Allegheny and Conemaugh Formations have a higher proportion of sandstone and clay shale and a lower proportion of limestone than the Monongahela and Dunkard Group. Information about the regional geologic units is summarized below: Allegheny and Pottsville Groups, Undivided: this geologic unit is as much as 700 feet thick and consists of shale, siltstone, claystone, sandstone, limestone, and coal. The shale is calcareous in part, and locally contains marine fossils. Siltstone in this group is thin bedded to medium bedded and locally contains marine fossils. The sandstone is mostly very fine to medium grained with limestone in the upper third of unit, conglomeratic in the lower third of the unit. Coal is mostly banded bituminous and generally in discrete beds. Conemaugh Group: this geologic unit contains a calcareous shale, a thin bedded to nonbedded siltstone, mudstone, fine to medium grained and thin to massive cross bedded sandstone, and thin layers of limestone and coal. The unit is as much as 500 feet thick and lateral and vertical lithic variability and gradation is common. Monongahela Group: this unit is as much as 350 feet thick and contains shale, siltstone, mudstone, sandstone, limestone, and coal. Similar to the Conemaugh group, lateral and vertical lithic variability and gradation is common. Dunkard Group: Around two thirds of this 600 feet thick unit is composed of mudstone, shale, and siltstone. Approximately one third is a fine grained to locally conglomeratic sandstone. The small remaining portion is limestone and coal, which are best developed in the lower 90 to 200 feet of the unit. Quaternary Alluvium: this unit contains alluvial deposits of sand, gravel, silt, and clay. ME1292/257.73(c)(1) History of Construction FNL 5 October 2016 pdf 8 of 24

9 3.5.3 Foundation Materials Field and laboratory data relevant to the physical and engineering properties of the foundation materials is available from previous site investigations. A summary of those properties, as indicated by various subsurface investigations, is presented below. A project report from the US Army Corps of Engineers summarizes the subsurface investigation supporting the design and construction of the New Cumberland Lock and Dam located on the Ohio River adjacent to the North and South Ponds (USACE, 1945). The report and accompanying boring logs indicate that the native soils beneath the embankment fill are comprised of brown silt and sand with some clay to an elevation of approximately 650 ft and a gravel, sand, and silt stratum to an approximate elevation of 605 ft. Bedrock is identified at an elevation of approximately 605 ft with firm rock indicated at an elevation of 602 ft. L.R. Kimball (2006, 2007) presents the results of a geotechnical investigation of various areas outside of the North and South Pond embankments performed in support of general site construction. The boring logs presented by L.R. Kimball (2006, 2007) show that the native soil consists of various layers of clay, silty clay, sandy clay, silty sand, and sand and gravel. Both sand and gravel ranged from fine to coarse particles. Laboratory tests on the fine-grained native material indicate that the materials generally comprise low-plasticity silts and clays and silty sand (United Soil Classification System [USCS] classifications CL, ML, and SM) with plasticity index less than 20. Fill material overlying the native soil generally comprises coal ash, slag, silty clay, clayey sand, sand, gravel, and cobbles. Boring logs presented by L.R. Kimball (2007) and Geosyntec (2016a) show the east embankment foundation soils to be similar to the native soils described above for the areas outside of the North and South Pond embankments. That is, foundation soils comprise silt and clay underlain by sand and gravel. Laboratory testing results presented by Geosyntec (2016a) indicate the fine-grained material is low-plasticity clay (CL) with plasticity index less than 20. All boring logs show the consistency or stiffness of the foundation soil, as indicated by the Standard Penetration Test (SPT) blowcount (N) to vary with depth. Further discussion of the engineering properties of the foundation soils is presented in the Periodic Safety Factor Assessment, Stratton, Ohio (Geosyntec, 2016a) Abutment Materials The North and South Ponds are formed on two sides and one side, respectively, by at-grade embankments that also act as abutments to the upground embankments forming the remaining sides of the ponds. The at-grade abutments consist of fill materials as indicated by the results of geotechnical investigations of the areas to the north and west of the ponds performed by L.R. Kimball (2006, 2007). A description of physical and engineering properties of the native and fill materials observed during those investigations is presented in Section ME1292/257.73(c)(1) History of Construction FNL 6 October 2016 pdf 9 of 24

10 3.6 Description of the Materials, Methods, and Dates of Construction Overview The results of subsurface investigations of the North and South Pond east embankments are presented by L.R. Kimball (2007), GAI (2009), and Geosyntec (2016a). Field observations indicate that the embankment fill material generally consists interbedded deposits of sand, gravel, and low-plasticity clay and fly ash. Embankment fill was observed from the ground surface at approximately elevation 695 ft-msl to elevations between 660 ft-msl and 670 ft-msl. Sand and gravel particle sizes range from fine to coarse. SPT blowcounts indicate very loose to dense sands and gravels, very soft clays, and very soft to very stiff fly ash deposits. Further discussion of the engineering properties of the embankment materials is presented by Geosyntec (2016a). Records of the construction methods and dates of construction of the North and South Pond were obtained from historical and contemporary design drawings provided by FirstEnergy and design drawings of the North Cumberland Locks and Dam. A listing of the specific drawings reviewed is provided in Section 3.7. The drawings provide an approximate timeline of the development of the North and South Ponds. The following is a description of the construction sequence and primary features associated with development of the Ponds Initial Construction Circa 1959 The North and South Ponds are absent from design documents dated June 1945, which illustrate construction of the New Cumberland Lock and Dam. The earliest identified engineering drawing to make reference to CCR management in the current location of the North and South Ponds, is a 1959 Yard Grading Plan (Drawing No. O-ST-780-G1907) prepared by Commonwealth Associates Inc. This drawing identifies construction of two disposal areas (Fill Area #1 and Fill Area #2) for management of Ash. The drawing illustrates grading for construction of two east to west oriented dikes which are approximately coincident with the southern embankments of the current South and North Ponds. A topographic rise provides containment to the north of the fill area, while the embankment of State Highway Route 7 provides containment to the east. A third dike along the west side completes the containment area. Along the eastern boundary construction of a 24-inch RCP is proposed. The inlet to the pipe is identified as a permanent manhole and skimming weir. Along the northern boundary construction of a 48-inch diameter reinforced culvert pipe (RCP) oriented west to east is proposed. The inlet to the pipe is adjacent to existing railroad tracks and appears to convey run-on from off-site areas. These two pipes meet in a depressed area outside of the containment areas in the northeastern corner of the site. Discharge from the pipes is directed into a 7-ft by 5-ft existing box culvert beneath State Route 7. Cross sections through the site illustrate proposed leveling of the fill areas using existing ash, placement of future ash to an elevation of approximately 689 ft-msl and subsequent capping of the ash fill with six inches of earth cover. ME1292/257.73(c)(1) History of Construction FNL 7 October 2016 pdf 10 of 24

11 Information regarding the construction materials, methods, and specific timeframes for the initial construction phases is not available Pond Modifications Circa 1967 A series of drawings for the South Ash Disposal Area project, prepared Commonwealth Associates Inc. and dated May 1967, identify modifications to the North and South Pond. These plans identify multiple revisions continuing from May 1967 through April The drawings are titled South Ash Disposal Areas Plan and Section, Details, and Dewatering and Diking (Drawing Nos. O-ST- 780-G2911-1, -2, and -3, respectively). These plans show the location and increased height of the perimeter embankments, include grading of the current east-west oriented finger berms within each pond, and indicate relocation of the 48- in RCP north of the previously installed location. Details include construction of new North and South Pond concrete discharge structures, which are connected to the previously-constructed 24-in and 48-in diameter concrete pipes. Crosssections through the site illustrate existing ash at elevations at 691 ft-msl and indicate excavation of ash is required to an elevation of 680 ft-msl. Information regarding the construction materials, methods, and specific timeframes for this series of pond modifications is not available Pond Plans Circa 1980 A series of drawings prepared by Commonwealth Associates, dated April 1979 and April 1980, show further development and modification of the North and South Ponds. These drawings provide a general overview of site drainage and topography circa 1979 by showing the location of the 48-in and 24-in concrete pipes and backfilling of the northeastern corner of the site. The April 1980 drawings titled North Ash Pond Dike Rehabilitation and South Yard Ash Piping Relocation Plan and Details (Drawing Nos. S780G and S780G , respectively) provide information pertaining to grading and reconstruction of the North Pond north embankment to accommodate placement of at-grade pipe racks to support process water effluent piping. Information regarding the construction materials, methods, and specific timeframes for this series of pond modifications is not available Pond Modification and Discharge Piping Upgrades Circa 2007 During the mid-2000 s new facilities were constructed at the western end of the North and South Ponds. Construction of the new facilities required backfilling portions of the North and South Ponds. The resulting grades are consistent with the topography illustrated on the drawing titled Ash Ponds from Aerial Photography Dated April 28, 2015 (L.R. Kimball, 2016). A copy of this drawing is provided in Appendix A. ME1292/257.73(c)(1) History of Construction FNL 8 October 2016 pdf 11 of 24

12 In 2007 the existing 24-in RCP South Pond discharge pipe was modified by slip lining the initial 270 feet of the pipe with a high-density polyethylene (HDPE) liner and replacing another 270 of the pipe RCP with a new 30-in diameter SDR 11 HDPE pipe. The abandoned RCP pipe was sealed and backfilled using flowable fill. Additional information regarding the construction materials, methods, and specific timeframes for the South Pond discharge pipe modification are not available Pond Outlet Modification and Discharge Piping Upgrades 2016 In June 2016, several alterations were made to the hydraulic structures discharging from and beneath the North and South Ponds. The alterations were approved, prior to construction; by the ODNR Dam Safety Program. The following modifications were made to the hydraulic features of the North and South Ponds: Replacement, slip-lining, and grouting of various section of the existing reinforced concrete stormwater conveyance pipe located along the north embankment of the North Pond; Installation of three new manholes along the stormwater pipe at north embankment of the North pond; Installation of an ungated overflow parallel to the normal North Pond discharge structure; Replacement of the existing 24-in reinforced concrete North Pond discharge pipe; Installation of an ungated 12-in diameter overflow pipe between the South Pond and North Pond; and Installation of stainless steel fixed-elevation weir plates in the North Pond discharge structure. A similar weir plate is to be installed in the South Pond discharge structure at a future time when the South Pond is out of service for cleaning and maintenance. The existing reinforced concrete stormwater pipe was replaced with HDPE pipe for the total length of the North Pond north embankment (approximately 450 ft). Pipe sections upstream and downstream of the north embankment were slip lined with HDPE pipe. The north embankment of the North Pond was reconstructed following the modifications to the hydraulic structures. The embankment was reconstructed to the design lines and grades shown on Drawing No. 3 of the construction drawings set, Stormwater and North Pond Discharge Pipe Replacement (Geosyntec, 2016c). Materials and methods of construction of the 2016 modifications conform to the specifications discussed in Section Drawings Available drawings relevant to the design, construction, operation, and maintenance of the North and South Ponds are identified in the table below. Note that not all of the drawings listed below ME1292/257.73(c)(1) History of Construction FNL 9 October 2016 pdf 12 of 24

13 represent the current configuration of the North and South Ponds but were retained here as they provide relevant information regarding the history of the construction history of the units. Drawings that have been completely superseded (i.e., all aspects of the drawing are no longer applicable) are highlighted with a double asterisk (**) in the table below. IMPOUNDMENT FEATURE Plan view and Cross-Sections of Unit Foundation Improvements Drainage Provisions Spillways Diversion Ditches Outlets Instrument Locations Slope Protection Normal Operating Pool Elevation Maximum Pool Surface Elevation Expected Maximum Depth of CCR Features that could adversely affect the operation of the unit O-ST-780-G O-ST-780-G O-ST-780-G S780G RELEVANT DRAWING(S) Foundation improvements are not identified on any available drawings. OST-780-G OST-780-G G-ST ** S780G OST-780-G O-ST-780-G S780G ** Diversion ditches are not identified on available drawings. Drawing Nos. 1 & 2 from Inflow Design Flood Control System Plan,, Stratton Ohio (Geosyntec, 2016b) Ash Ponds from Aerial Photography Dated April 28, 2015 (L.R. Kimball, 2016) Figure 1 Location of Piezometers (GAI, 2009) Slope protection measures are not shown on available drawings. Drawing Nos. 1 & 2 from Inflow Design Flood Control System Plan,, Stratton Ohio (Geosyntec, 2016b) Drawing Nos. 1 & 2 from Inflow Design Flood Control System Plan,, Stratton Ohio (Geosyntec, 2016b) The depth of CCR is managed according to the effluent characteristics and cleaned from each basin on a regular basis. O-ST-780-G (South Pond discharge pipe leak) S780G (process piping leak) Drawing Nos. 3, from Inflow Design Flood Control System Plan,, Stratton Ohio (Geosyntec, 2016b) (stormwater pipe leak) ME1292/257.73(c)(1) History of Construction FNL 10 October 2016 pdf 13 of 24

14 3.8 Type, Purpose, and Location of Instrumentation Ten piezometers, all less than 12 feet in depth, were installed in the east embankments of the North and South Ponds and in the south embankment of the South Pond in February 2009 (GAI, 2009). The piezometers were installed approximately at the crest and toe of the downstream slopes of the embankments. The piezometer locations are shown on Figure 1, Location of Piezometers (GAI, 2009). The purpose of the piezometers is to monitor the water elevations in the embankment in support of a stability analysis (GAI, 2009). Two additional piezometers and eight groundwater monitoring wells were installed at various locations around the North and South ponds in May These instruments were installed to obtain groundwater elevation and groundwater samples for testing to support compliance demonstrations required by the CCR Rule. 3.9 Area-Capacity Curves Area-capacity curves (also known as Stage-Storage curves) provide a means to estimate the volume of material or water within an impoundment based upon the elevation of the material or water. The curves are a necessary input for computational evaluation of basin hydraulics and are a useful tool for estimating day-to-day volume of material or water within the impoundment based on easily obtainable measurements of elevation from a fixed staff gauge. Stage-Storage curves for the North and South Ponds, developed using the stage-area data compiled by Geosyntec (2016b) are presented in Appendix B. A review of the curves indicates a peak storage, as measured from the base of the pond to the lowest point of the embankment, of approximately 31 ac-ft and 60 ac-ft for the North and South Pond, respectively. Storage volumes associated with other key elevations, such as the weir elevation and normal and peak operating water surface elevations, can be read from the curves. For reference, key elevations are also provided on the stage-storage curves Spillway Description and Calculations The North Pond outlet riser is fitted with a weir plate to control the water elevation. The maximum water elevation is controlled by a 48-in open stand pipe which is set six inches above the normal operating water level. Water passes from the base of the outlet riser through a buried 24-in diameter HDPE pipe end enters into a concrete manhole in the northern embankment of the pond. The manhole is part of a storm drain network which is buried along the northern perimeter of the North Pond. The storm drain network passes run-on water form west side the Plant to the Ohio River and terminates at an endwall structure located adjacent to State Route 7 at the northeast corner of the North Pond. As noted in Section 1.3, water is discharged from the North and South Ponds under an OEPA NPDES permit. The South Pond outlet riser is intended to be retrofitted with a weir plate to control the water elevation, as noted in Section 1.3, and illustrated on drawing 2 from Inflow Design Flood Control System Plan,, Stratton Ohio (Geosyntec 2016b). ME1292/257.73(c)(1) History of Construction FNL 11 October 2016 pdf 14 of 24

15 The maximum water elevation will be controlled by an overflow pipe positioned six inches above the normal operating water level and set into the northern embankment of the South Pond. Water passes from the base of the outlet riser into a buried a culvert buried within the eastern embankment of the South and North Ponds. This culvert consists of multiple segments separated by manholes. The segments are constructed of either RCP that has been sealed with an HDPE liner and segments constructed of solid wall pipe manufactured from high density polyethylene (HDPE). This culvert intersects the same 48-in diameter storm drain network to which the North Pond discharge is connected. Further information on hydraulic computations supporting the design of the North and South Pond outlet structures are provided by Geosyntec (2016b) Construction Specifications and Provisions for Operations and Maintenance Other than the identification of material types on the available drawings, no specifications pertaining to the initial construction of the North or South Pond were identified. Material and construction specifications for construction activities related to the 2016 modifications to pond outlet and discharge structures are included as part of the drawing set titled, Stormwater and North Pond Discharge Pipe Replacement Drawings (Geosyntec, 2016c). Provisions for the operation and maintenance of the Ponds are described in the document, Operations and Maintenance Manual for Sammis Station North Bottom Ash Dam (First Energy, 2014b). Additional information regarding provisions for action to be taken in the event of an emergency are presented in the document Emergency Action Plan (EAP) for Sammis Station North Bottom Ash Dam (First Energy, 2014a) Record of Structural Instability GAI (2009) indicates that a sink hole occurred in the eastern embankment of the north pond during construction of the 30-in HDPE discharge pipe beneath the east embankment of the North Pond. GAI (2008, 2009) indicates that the sinkhole was backfilled with concrete. ME1292/257.73(c)(1) History of Construction FNL 12 October 2016 pdf 15 of 24

16 4. REFERENCES FirstEnergy Generation, LLC (First Energy) (2014a). Emergency Action Plan for Sammis Station North Bottom Ash Dam, Jefferson County, Village of Stratton, ODNR, DSWR File Number: April FirstEnergy Generation, LLC (First Energy) (2014b). Operations and Maintenance Manual for Sammis Station North Bottom Ash Dam, Jefferson County, Village of Stratton, ODNR, DSWR File Number: Draft. April GAI (2008). Dike Inspection North and South Ash Ponds W.H. Sammis Power Plant, Stratton, Ohio. GAI Consultants, Homestead, PA. August GAI (2009). Piezometer Installation and Stability Analyses, North and South Ash Ponds, W.H. Sammis Plant, Stratton, Ohio. GAI Consultants, Homestead, PA. November Geosyntec (2016a). Safety Factor Assessment W.H. Sammis Coal Plant, North and South Ponds, Stratton, Ohio. Geosyntec Consultant s, Inc. 17 October Geosyntec (2016b). Inflow Design Flood Control System Plan, W.H. Sammis Coal Plan North and South Ponds, Stratton, Ohio. Geosyntec Consultants, Inc. 17 October Geosyntec (2016c). Stormwater and North Pond Discharge Pipe Replacement. Geosyntec Consultant s, Inc. 24 May L.R. Kimball (2006). W.H. Sammis Plant Geotechnical Investigation. L. Robert Kimball & Associates. February L.R. Kimball (2007). First Energy Sammis Project. L. Robert Kimball & Associates. May L.R. Kimball (2016). Ash Ponds from Aerial Photography Dated April 28, L. Robert Kimball & Associates. February Ohio Division of Geological Survey (2006). Bedrock geologic map of Ohio: Ohio Department of Natural Resources, Division of Geological Survey Map BG-1. United State Army Corps of Engineers (USACE) (1945). Definite Project Report on New Cumberland Locks and Dam Ohio River. US Engineer Office, Pittsburgh, PA. June United States Environmental Protection Agency (USEPA) (2015). Hazardous and Solid Waste Management System; Disposal of Coal Combustion Residuals from Electric Utilities; Final Rule. Title 40 Code of Federal Regulations, Parts 257 and 261. ME1292/257.73(c)(1) History of Construction FNL 13 October 2016 pdf 16 of 24

17 pdf 17 of 24 FIGURES

18 ³ P:\GIS\Sammis Power Station - ME1292\Report 1\Figure 1 - Site Location Map N&S Ponds.mxd; RDW/MS; 13-Oct-2016 North and South Ponds Notes: Topographinc map provided by U.S Geological Survey on 13 October East Liverpool South, West Virginia (1985), and Wellsvill, Ohio (1986) 2,000 1, ,000 Feet Site Location Map: North and South Ponds Sammis Power Station Stratton, Ohio Figure Columbia, Maryland pdf 18 of 24 October

19 ³ Discharge at Headwall Ohio Route 7 48-in RCP 30-in HDPE 24-in RCP with HDPE Liner 24-in HDPE Outlet Riser and Valve Vault Primary Outlet 3 Outlet Riser and Valve Vault Primary Outlet 48-in HDPE Overflow Outlet 12" HDPE Overflow Outlet 48" HDPE North Pond South Pond 3 48" RCP with HDPE Liner P:\GIS\Sammis Power Station - ME1292\Report 1\Figure 2 - Site Plan N&S Ponds.mxd; MS/RDW; 13-Oct-2016 pdf 19 of 24 3 Legend 3 Manhole 24 inch pipe 30 inch pipe 48 inch pipe Notes: RCP - Reinforced Concrete Pipe HDPE - High-Density Polyethylene 1. Aerial imagery accessed via ArcGIS Online and provided by the United Stated Department of Agriculture on 13 October Image is dated 24 October All pipe and structure locations are approximate Feet Site Plan: North and South Ponds Sammis Power Station Stratton, Ohio Columbia, Maryland October 2016 Figure 2

20 APPENDIX A Drawings pdf 20 of 24

21 N LEGEND OF SYMBOLS AND ABBREVIATIONS MAJOR CONTOUR PIEZOMETER W E MINOR CONTOUR UNDERGROUND DRAINAGE LINE GUARD RAIL MANHOLE POST SIGN S 615 West Highland Ave. Ebensburg, Pa FENCE LINE LIGHT POLE EDGE OF WATER UTILITY POLE CONSULTANTS: PROJECT NAME: FIRST ENERGY W.H. SAMMIS PLANT STRATTON, OH OWNER: FIRST ENERGY W.H. SAMMIS PLANT STATE ROUTE 7 STRATTON, OH NOTES: 1. Source of topographic information: From ground control surveys January 18 and 29, 2016 and from aerial photography dated April 28, Horizontal control is based on OH North NAD83, State Plane Coordinates by the KeyNET VRS Network. All coordinates are true state plane. 3. Vertical control is based on NAVD88 vertical datum, GEOID12A by the KeyNET VRS Network. 4. Underground utility locations are by others and were not verified by L.R. Kimball using remote sensing techniques. C 2/22/2016 ADDITIONAL MAPPING B 2/15/2016 ADD. UG PIPE PER A 2/2/2016 ADD. UG PIPE / PIEZO. REV. DATE DESCRIPTION ISSUE: 1/22/2016 PROJECT NO: SCALE: DRAWN BY: CHECKED BY: WRB JAW CDI Infrastructure, LLC dba L.R. Kimball SHEET TITLE ASH PONDS FROM AERIAL PHOTOGRAPHY DATED APRIL 28, Feet pdf 21 of 24

22 APPENDIX B Stage-Storage Curves pdf 22 of 24

23 Geosyntec Consultants 696 Stage-Storage Curve FirstEnergy W.H. Sammis Coal Plant North Pond Impoundment 694 Top of Embankment; ft msl Elevation (ft-msl) Water Surface Elev. at 0.5 PMF Water Surface Elev at Normal Operations Crest of Overflow Bottom of Fixed Weir Pond Storage (ac-ft) Curve is based on elevation-area data presented in the report, pdf 23 of 24 Inflow Design Flood Control System Plan, (Geosyntec, 2016b).

24 Geosyntec Consultants 698 Stage-Storage Curve FirstEnergy W.H. Sammis Coal Plant South Pond Impoundment 696 Top of Embankment; ft-msl Water Surface Elev. at 0.5 PMF Water Surface Elev at Normal Operations Crest of Overflow Elevation (ft-msl) Bottom of Fixed Weir Pond Storage (ac-ft) Curve is based on elevation-area data presented in the report, pdf 24 of 24 Inflow Design Flood Control System Plan, (Geosyntec, 2016b).