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Home My WebLink AboutNCG021046_Erosion & Sediment Control Plan_20240923 Erosion and Sediment Control Plan Addendum 2. 1 Kings Mountain Mining Project Report Date: June 25, 2024 Report Prepared for A ALBEMARLE' Albemarle Corporation 4250 Congress Street Charlotte, NC 28209 Report Prepared by =%*opff srk consulting SRK Consulting (U.S.), Inc. 999 171h Street, Suite 400 Denver, CO 80202 SRK Project Number: USPR000576 Albemarle Document Number: KM60-EN-RP-9052 North Carolina Firm License Number: C-5030 Author: David Hoekstra, BS, PE, NCEES, SME-RM, Principal Consultant Reviewed by: Gary Hurban, M.S., PE, Principal Consultant SRK Consulting(U.S.), Inc. Erosion and Sediment Control Plan Template—Kings Mountain Page ii Table of Contents 1 Project Description...................................................................................................... 1 1.1 Site Description...................................................................................................................................1 1.2 Property History ..................................................................................................................................3 1.3 Project Overview.................................................................................................................................3 1.3.1 Adjacent Properties.................................................................................................................4 1.3.2 Existing Drainage System.......................................................................................................6 1.4 Soils 6 MapUnit Legend ............................................................................................................... 8 2 Site Development Plan ................................................................................................ 9 3 Construction Schedule.............................................................................................. 11 4 Planned Erosion and Sedimentation Control Practices ......................................... 12 4.1 Permanent Development and Operational Stage Practices.............................................................12 4.1.1 Permanent Sediment Control Ponds.....................................................................................12 4.1.2 Sediment Control Pond 1 (Skimmer Sediment Basin-Practice 6.64)....................................13 4.1.3 Sediment Control Ponds 62 and 63 (Skimmer Sediment Basin-Practice 6.64)....................13 4.1.4 Sediment Control Pond 64 (Skimmer Sediment Basin-Practice 6.64)..................................13 4.1.5 Permanent Grass-Lined Channels (Practice 6.21 and Practice 6.30)..................................13 4.1.6 Permanent Riprap-Lined Channels (Practice 6.21 and Practice 6.31).................................13 4.1.7 Permanent Outlet Protection Level Spreader (Practice 6.40)...............................................14 4.1.8 Operational Dust Control (Practice 6.84)..............................................................................14 4.1.9 Permanent Revegetation Practices.......................................................................................14 4.1.10 Closure Surface Grading (Practice 6.02)..............................................................................14 4.1.11 Closure Surface Topsoiling, Roughening, and Revegetation (Practices 6.04, 6.03, and 6.11) 14 5 Maintenance Plan....................................................................................................... 15 6 Detail Drawings and Specifications for Practices Specified.................................. 16 7 Vegetation Plan.......................................................................................................... 17 8 Supporting Calculations............................................................................................ 18 9 Financial Responsibility/Ownership Form......................Error! Bookmark not defined. 10 Checklist............................................................................Error! Bookmark not defined. 11 References.................................................................................................................. 19 Disclaimer........................................................................................................................ 20 Copyright ......................................................................................................................... 20 MH/DH April 2024 SRK Consulting(U.S.), Inc. Erosion and Sediment Control Plan Template—Kings Mountain Page iii List of Tables Table 4.1: Summary of Sediment Ponds Characteristics.................................................................................13 Table 7.1: Preliminary Seed Mix Composition and Schedule ..........................................................................17 List of Figures Figure1-1: Location Map....................................................................................................................................2 Figure 1-2: Stream Network and Adjacent Properties........................................................................................5 Figure1-3: Soil Survey Map...............................................................................................................................7 Figure 1-4: Soil Survey Map Legend..................................................................................................................8 Figure2-1: Site Location Map ..........................................................................................................................10 Figure 6-1: Skimmer and Riser Sediment Basin with Permanent Wet Pond .... Error! Bookmark not defined. Figure 6-2: Section through Sediment Pond 1 .................................................. Error! Bookmark not defined. Figure 6-3: Section through Sediment Pond 62 ................................................ Error! Bookmark not defined. Figure 6-4: Section through Sediment Pond 63 ................................................ Error! Bookmark not defined. Figure 6-5: Section through Sediment Pond 64 ................................................ Error! Bookmark not defined. Figure 6-6: Typical Riprap Channel Cross Section ........................................... Error! Bookmark not defined. Figure 6-7: Outlet Stabilization Structure........................................................... Error! Bookmark not defined. Appendices Appendix E-1A: Runoff Estimation for the Kings Mountain Mining Project Appendix El-B: Channel Design for the Kings Mountain Mining Project Appendix El-C: Sediment Pond Designs MH/DH April 2024 SRK Consulting(U.S.), Inc. Erosion and Sediment Control Plan Template—Kings Mountain Page iv List of Abbreviations The US System for weights and units has been used throughout this report. Tons are reported in short tons of 2,000 lbs. All currency is in U.S. dollars (US$) unless otherwise stated. Abbreviation Unit or Term AOI area of interest ° degree(degrees) dia. diameter ECP erosion and sediment control plan ft foot feet ft2 square foot feet ft3 cubic foot feet al gallon m gallons per minute HAV horizontal to 1 vertical HDPE high density of eth lene lb pound LI li ht industrial LoM life-of-mine MSHA Mine Safety and Health Administration PAG potentially acid generating % percent PFS prefeasibility stud PMP probable maximum precipitation PMF probable maximum flood RoM run-of-mine sec second sed pond Sedimentation Pond SG specific gravity SR suburban residential t/d tons per day t/Y tons per year Tailings finely ground waste rock from which valuable minerals or metals have been extracted. TSF tailings storage facility TSP total sus ended particulates m micron or microns WSB water storage basin year MH/DH April 2024 SRK Consulting(U.S.), Inc. Erosion and Sediment Control Plan Template—Kings Mountain Page 1 1 Project Description The Kings Mountain Mining Project(the Project) is a legacy open pit lithium mining operation located in the city of Kings Mountain, North Carolina, in the southeastern United States.The Project is a lithium pegmatite deposit being investigated for redevelopment by Albemarle Corporation (Albemarle)as part of a prefeasibility-level analysis. Albemarle commissioned SRK Consulting (U.S.), Inc. (SRK) to develop prefeasibility-level (evaluate and Select phases, per Albemarle's internal conventions) designs for an expansion of the existing pit, waste rock management, water management, and ancillary infrastructure to aid Albemarle in making informed decisions concerning advancement of the Project. As part of this study, SRK is developing a prefeasibility study surface water design of stormwater management controls to divert clean, non-contact water around the facilities. At the same time, the design intercepts waters that have encountered mining activities and routes them to monitoring or treatment facilities prior to discharge into the existing natural drainage system. The Surface Water Management Plan (SWMP) for the project is expected to be a living document, and as such will include occasional addendums to address modifications to the SWMP that do not warrant a complete revision of the original SWMP. The current SWMP for the project is Version 2.0 and this document is Addendum 2.1, representing the first addendum to SWMP Version 2.0. 1.1 Site Description Situated in Cleveland County, the mine is approximately 35 miles west of Charlotte, North Carolina. Located amidst rolling hills of the Piedmont Plateau, the Project is in a rural setting within the city of Kings Mountain. The mine site covers a significant area of land, which includes both the proposed extraction areas and associated processing infrastructure. Figure 1.1 shows the location of the mine. MH/DH April 2024 SRK Consulting(U.S.), Inc. Erosion and Sediment Control Plan Template—Kings Mountain Page 2 a� main �f.ce4 p.r -----, rr � BeaaemerGlCy `_------______..,_ Yanlitle 1 h. A� ti� 91ue Riuge 7-0 ti Pa kNMy Rntlt.y, � S� f Oak Grove Gr6}r9 hi. Sk Ly cunl:ain vlow �� Ifings hAountairi ' I Cmeyders MlriFs�� I Mountain Sieie Kings • Park y f Mountain A,cr,UlIE Project 5rd[eWllie � Idr4ry •hniilc L� South Mountains State Park Mavresville North Carolina t f ~ r Gasmnia ChdfiQCte 4 17Ay 0Spartar burg 1000�' O M1+#} GreerwIlle South Carolina 371 Source:Environmental Systems Research Institute,Inc.(ESRI),2023(modified by SRK) Figure 1-1: Location Map MH/DH April 2024 SRK Consulting(U.S.), Inc. Erosion and Sediment Control Plan Template—Kings Mountain Page 3 1.2 Property History The following summary highlights the history of the site, compiled from records available to SRK: • Mining started in 1883 with the discovery of cassiterite, a tin-bearing mineral, within the outcropping pegmatites. • Subsequently, open pit mining for tin occurred sporadically between 1903 and 1937 (Horton and Butler, 1988). • Between 1943 and 1945, under the sponsorship of the U.S. government, Solvay established a processing plant and mined for spodumene from the outcropping pegmatites(Garrett,2004). • In the early 1950s, Foote Mineral Company (Foote), a subsidiary of Newmont Mining Corporation, purchased the property and began open pit mining (assumed at the beginning of 1955) and extracting lithium from the spodumene. • In 1993, exploration and mining operations ceased when the open pit bottom reached approximately 660 feet(ft) above mean sea level (amsl). • In early 1994, an open pit lake started to form due to rebounding groundwater, and the pit lake reached an elevation of 818.67 ft amsl (as of November 2023). • During the groundwater recovery period (1994 to present), water was sporadically pumped from Kings Mountain pit lake to a nearby quarry (Martin Marietta)to support quarry operation. • Albemarle acquired the site in 2015, resuming exploration and mine development activities. 1.3 Project Overview The Project ore deposit is a lithium-bearing rare-metal pegmatite intrusion that has penetrated along the Kings Mountain shear zone, a regional structural feature known to host multiple lithium-bearing pegmatites along its trend. The pegmatite field at Kings Mountain is approximately 1,500 ft wide at its widest point in the legacy pit area and narrows to approximately 400 to 500 ft in width at its narrowest point south of the legacy pit. The field has a lithium mineralization strike length of approximately 7,500 ft and is predominantly contained in the mineral spodumene. The spodumene pegmatite bodies exhibit a texture-based variation in lithium grade, spodumene grain size, mineral alteration, and rock hardness. After dewatering the legacy pit, the lithium deposit is to be mined using conventional open pit mining techniques. Overburden soils associated with pre-mining activities and foundation preparation will be removed and stockpiled in the Overburden Stockpile Facilities (OSF). Blasting will fragment the ore and waste rock where it will be loaded and hauled to either the processing facilities (ore) or the rock storage facilities (RSF) (overburden). The current plan includes mining in the existing pit and expanding the pit to the southwest. Ore will be drilled, blasted, loaded, and transported by haul truck to a new processing plant at a rate of approximately 2.98 million tons per annum of ore (approximately 8,150 tons per day) and processed to produce 380 to 420 thousand tons per annum of spodumene concentrate. The concentrate will be filtered to approximately 11 percent (%) moisture by weight and transported off-site for further refinement into lithium hydroxide monohydrate at a separate facility. Tailings from the spodumene concentrate process will be filtered to approximately 10% to 15% moisture content by weight and transported off-site to a nearby facility for disposal. A portion of the waste rock with economic value as aggregate will also be transported off-site for sale. MH/DH April 2024 SRK Consulting(U.S.), Inc. Erosion and Sediment Control Plan Template—Kings Mountain Page 4 1.3.1 Adjacent Properties The natural drainage network near the Project is heavily influenced by legacy and active mining activities. Land use in the area is a mix of suburban residential(SR)and light industrial (LI).The Project area is bounded by Battleground Avenue to the north, Tin Mine Road to the west, Church and York roads to the south and east, and Cardio Hill (a legacy RSF) to the northeast. Properties to the north and east of the Project site are typically residential along Tin Mine Road and Battleground Avenue, while the Martin Marietta Kings Mountain quarry bounds the Project area to the east and southeast. The Project area is bisected by Interstate Highway 85 (185), passing northeast to southwest to the property, with most Project construction activities occurring north of the highway. Commercial properties are located south of 185 and north of Water Storage Basin (WSB)-1, a remnant from previous mining activities. The southern edge of the property is bounded by York Road and Galilee Church Road, with residential and commercial properties along these roads. South of Galilee Church Road lies the Kings Mountain Number One Lake. Figure 1.2 shows these features. MH/DH April 2024 . ..- r Kiwgsm,,'Iur-tain rt• .. - .; - - - flayry ■ x eV U� - �n JS`J!7 ��c9j�' i■ f .c +F i • • a 5 ti� � '=f0 i111Y21aY'hZ�� MIB mom& @* Ub Q' k o a M1 F 4. e�q Ra. r O SRK Consulting(U.S.), Inc. Erosion and Sediment Control Plan Template—Kings Mountain Page 6 1.3.2 Existing Drainage System The Project areas include two major drainages: Kings Creek passing from the northeast to the southwest of the Project and South Creek, which forms within the northwestern portion of the Project area and joins with Kings Creek north of 185. The Project area includes a number of constructed water bodies remaining from previous mining activities, including the Kings Mountain pit lake(a closed water body in the legacy Kings Mountain open pit), the South Creek reservoir (a reservoir constructed adjacent to the legacy mine tailings facility), and WSB-1 (a shallow water body formed by the remnants of a legacy mine tailings facility). South Creek flows along the west side of the Project area before entering the South Creek reservoir. The spillway from the South Creek reservoir is two 32-inch-diameter culverts that discharge into a rock-lined downchute that routes flow to the confluence with Kings Creek. The closed depression formed by the existing tailings facility (also known as Foote Mineral Tailings Pond) has no overland outlet, but increased groundwater contributions to South Creek are observed in the vicinity of the tailing's embankment. Kings Creek is intercepted upstream of the Project area by the Martin Marietta quarry, and most flow in Kings Creek is the result of pumping from the existing Martin Marietta quarry (also known as Kings Mountain Mica Company Lake) into Kings Creek. The pumping system was recently upgraded to 2,500 gallons per minute (gpm). Kings Creek passes to the south of the existing Kings Mountain pit in a steep ravine and is routed under the Albemarle research building through an existing 4-ft-diameter culvert. Downstream of the culvert, Kings Creek joins with the discharge from the South Creek reservoir before crossing under 185 through three 7-ft x 10-ft concrete box culverts. Flowing to the southwest, Kings Creek joins with the discharge from WSB-1 before flowing off the Project area to the southwest. There are numerous small ponds in the Project area; the most significant is Pond#1, centrally located, which intercepts runoff from the area before intermittently discharging to Kings Creek. Figure 1.2 shows the stream network. 1.4 Soils Soil mapping provided by the United States Department of Agriculture — Natural Resources Conservation Service (USDA NRCS) (2023) indicates that the soil composition in the Kings Mountain area is characterized by a mixture of loamy and clayey soils with varying degrees of organic matter content, gravels, and sands. Figure 1.3 shows the soil unit mapping, with the map legend included as Figure 1.4. Within the area of interest, the soil mapping indicates approximately 50% of the soil is represented by two soil types: 24% of the area of interest (AO1) is the Madison-Bethlehem complex, and 25% of the AO1 is the Uwharrie silt loam. Both the Madison and Uwharrie soils are classified as Hydrologic Soil Group B, while the Bethlehem soil unit is Hydrologic Soil Group C. MH/DH April 2024 �K ya adowtiroo'f ! ` _ � -4 v OS G� 'q` .) "9� r � eiy ,•S ,f �, It I 73, .Mb62 • '�Y k tgd y.. UxB r, ` Y. 7;�r�3 ��B W Pw � �r - - .l _� �rowdgr$.G�eO U.dC �. . C Mb62 � 5... ` �•" mtc• f c+rr McC2 Y f vG MbB2�' f �aa GrQ� - i4l TaQ UTT`2 f ar ` 3 UdC MCC2 i. v w• ,+ MnB ^1 UtB' McC2 Z TaB H ChA � w � if r. MbB2' Tao W ChA F . MbB2 t7AM � UtB McC2 CaB2 Uvo ChA USG �( TaC '-aB \ 'LItB \ U 2 uB UwC2' Tal]• U0 2AL • tm r TaDI �• 'k. '4*. LwG UDC � u � A. R: SRK Consulting(U.S.), Inc. Erosion and Sediment Control Plan Template-Kings Mountain Page 8 MAP LEGEND MAP INFORMATION Area of Ini1erest(AOI) Spoil Area The soil surveys that comprise your ADl were mapped at 0 Area at Interest(AOI) 1:24 X0. � �°"'� ot Map Unit Legend s01lsIM very Stony spot Please rely on the bar scale on each rnap sheet far map 0 Sail Map Unit Polygons measurements. Map Unit Map Unit Name Acreage in Percentage r.o Sail Map Unit Lines Symbol Cecil sandy clay loam,2%to 8%slopes,moderately Wet Spot bol AOI(acres(ac)) of AOI Other Source of Map: Natural Resources Conservation Service eroded 18.2 0.8 Sail Map Unit Points Web Soil Survey URL: ° ° /° �. Special Line Features ChA Chewacla loam,0/°to 2 slopes,frequently flooded 37.2 1.7 Special Point Features Coordinate System: Web Mercator(EPSG:3657) DAM Dam 31.1 1.4- VO Blowout Yhrter Features GrD Grover gravelly sandy loam, 15%to 30%slopes,rocky 44.2 2.0 Borrow Pit Streams and Canals Maps from the Web Soil Survey are based on the Web Mercator HhB Hulett gravelly sandy loam,2%to 8%slopes 10.1 0.5 projection,which preserves direction and shape but distorts Transportation HtC Hulett gravelly sandy loam,8%to 15%slopes,stony 28.6 1.3 X distance and area_A projection that preserves area,such as the Clay SW Rails Albers equal-area conic projection,should be used if more Madison-Bethlehem complex,2%to 8%slopes,stony, � P ] MbB2 179.0 8.2 ' Closed Depression accurate calculations of distance or area are required. moderate) eroded Interstate Highways very Madison-Bethlehem complex,8%to 15%slopes,ve McC2 100.9 4.6 Gravel pit US Rolfes stony,moderate) eroded This product is generated from the USDA-MRCS certifies data a- Madison-Bethlehem-Urban land complex,2%to 8% Gravelly Spat M3JOr Roads of the version date(s)listed below. MnB slopes 252.5 11.5 tyi Landfill MoE Montonia very channery silt loam,25%to 60%slopes, 1.8 0.1 Local toads Soil SunreyArea: Cleveland County,North Carolina very stony Lava Flow Background Survey Area Data. Version 26,Sep S, 2022 Pw Pits,quarry 105.7 4.8 Marsh or swamp Aerial Photography TaB Tatum-Montonia complex,2%to 8%slopes 19.4 0.9 Sail map snits are labeled(as space allows)for map scales TaC Tatum-Montonia complex,8%to 15%slopes 13.1 0.6 4* Mine or Ouarry 1:50,000 or larger_ TaD Tatum-Montonia complex, 15%to 30%slopes 55.2 2.5 Miscellaneous Water UdC Udorthents,loamy,0%to 15%slopes 652.7 29.7 Date(s)aerial images were photographed: Apr 22,2022-May UtB Uwharrie silt loam,2%to 8%slopes 120.9 5.5 0 Perennial Water 10, 2022 Uwharrie silty clay loam,2%to 8%slopes,moderately UuB2 eroded 178.E 8.1 Rock Outcrop The orthophoto or other base map on which the soil lines were UvC Uwharrie-Tatum complex,8%to 15%slopes 146.1 6.7 Saline Spot compiled and digitized probably differs from the background UwC2 Uwharrie-Tatum complex,8%to 15%slopes, 90.9 4.1 imagery displayed on these maps_As a result,some minor moderate) eroded _'• sandy Spat shifting of map unit boundaries may be evident_ UxB Uwharrie-Urban land,2%to 8%slopes 9.8 0.4 Severely Eroded Spot W Water 99.4 4.5 Sinkhole Totals for Area of Interest 2,195.4 100.0 Slide or Slip Sodic Spot Source:USDA NRCS,2023 Figure 1-4: Soil Survey Map Legend MH/DH April 2024 SRK Consulting(U.S.), Inc. Erosion and Sediment Control Plan Template—Kings Mountain Page 9 2 Site Development Plan Figure 2.1 shows the Kings Mountain Lithium Mine site development plan and shows facilities addressed in Version 2.0 SWMP (April 2024) and included in the associated Erosion control plan that are expected to be constructed by the end of Mine Year 8. The existing pit and pit lake are in the northeast corner of the site. The ultimate (Phase 1) open pit outline is shown in the northeast area of the Project. Haul roads are shown connecting the pit to the RSFs; RSF-X, located south-centrally for potentially acid generating(PAG)waste, and RSF-A, located in the southwest for non-PAG (NAG) waste. All PAG waste will be re-mined and used as pit backfill during reclamation and closure. The haul roads will also connect to the non-processing infrastructure (NPI), located in the northwest portion of the site, and the ore sorting area and the ore stockpiles, located on the east side of the Project just north of 185. A bridge over 1-85 will connect the ore stockpile area to the processing area, located immediately south of 1-85. WSB-1 will be constructed by restoring WSB-1 in the far southern portion of the Project area. WSB-1 will collect all contact water produced within the Project area before being discharged from the site. Linear infrastructure, such as access roads, haul roads, railroads, pipelines, water management ponds, and diversion channels, are located throughout the site, as needed. Facility expansion will occur over the life-of-mine, but, where feasible, surface water features will be constructed to address the final configuration. This addendum Version 2.1 addresses the addition of three overburden stockpiles (OSF-1,2, and 3) and their ancillary surface water management infrastructure. OSF-1 located north of RSF-A in a watershed contributing to South Creek, OSF-2 immediately west of the Pit Haul Roads in a watershed primarily contributing to Kings Creek, and OSF-3 located immediately south of RSF-A in a watershed contributing to South Creek. MH/DH April 2024 PERIMETER pJ�j N POND71 CIA LEGEND LAYARE OWN 56p- SEDIMENT FENCE � 003 NCG02 DISCHARGE PERIMETER �j POINT ID POND 72 PROPERTY / LINE GROWTH MEDIA STORAGE LAYDOWN / AREA TRUCK MAINTENANCE SHOP MINE PIT WAREHOUSE- I / - r � EXISTING ROM PAD FACILITY/LABORATORY \J- NATURAL GAS LINE RE-ROUTE — ♦ ,� ��P o READY LINE HAUL ROAD o , �o CONCENTRATE \\ / RAIL LOADOUT 1 81 EXISTING ( / \ PROCESS / BOOSTER PUMP FACILITY ki , OVERBURDEN STORAGE \ FACILITY 2 (OSF-2) \ SED POND 1 °� , OVERBURDEN � _ ® � / •��' STOCKPILE STORAGE SEDIMENT FACILITY 1 (OSF-1) � WETLAND AREA FENCE (TYP.) RAIL CAR 010� SETBACK FUELING STATION & INFRA STORAGE �'I SOUTH CREEK OSF-1 WATER CULVERT�� _ ❑ CRUSHING FACILITIE MANAGEMENT PONDS — \� _ / 063 a, / 163 MUD POND#2 V - 10671 GRADE TO DRAIN KING S CREEK ��, �� • j� 62 162 J _ CONCENTRATE TRUCK O SOUTH CREEK LOADING BUILDING - f � HAULROAD i - _ / FILL CHECKDAM PROPOSED ROCK 066 , ROCK 0 STORAGE FACILITY X =:_CONCENTRATOR -� - � ' FACILITIES , v p OF / '9\ ROCK rWRC POND 51 STORAGE G�- FACILITY A / 101 003 151 - - WATER STORAGE 068 �� /00, / BASIN 1 (CURRENT 102 OUTLINE) WRC POND 61 161 �'"—' i EXISTING 230kV 164 POWERLINE ALIGNMENTOSF-3 WATER � ` - MANAGEMENT POND WETLAND AREA 1 03 / SETBACK — � � PROPOSED WATER � STORAGE - -- EMBANKMENT SEDIMENT _ VERBURDEN STORAGE FACILITY 3 (OSF-3)- FENCE (TYP.) �� LAYDOW MAX WATER LEVEL ♦ YARD PIMP EVENT �004 PROPOSED TOE (845 FT AMSL) � BUTTRESS / I 230/24.9KV ELECTRICAL PROPOSED SUBSTATION SPILLWAY REVISIONS DESIGN:EL/JO REVIEWED:DPH PREPARED BY: DRAWING TITLE: ISSUE: REV. DESCRIPTION DATE DRAWN:EL APPROVED:JO SITE LOCATION MAP WITH TEMPORARY 0 ISSUED FOR PERMITTING 07/02/2024 Srk consultingDATE: COORDINATE SYSTEM: SURFACE WATER MANAGEMENT AND 7/2/2024 NC83F PREPARED FOR: SEDIMENT CONTROL FEATURES SRK PROJECT NO.: REVISION: PROJECT: USPR576.800 0 0 250 500 1000 KINGS MOUNTAIN MINING PROJECT DRAWING NO. FEET IF THE ABOVE BAR .1 ALBEMARLE KINGS MOUNTAIN MINING PROJECT Operated by: DOES NOT MEASURE 1 INCH, FIGURE 2. 1Albemarle-Lithium FILE NAME: Site Map_Rev 8_Silt Fencing_Linked.dwg THE DRAWING SCALE IS ALTERED C:\Users\elynn\SRK Consulting\NA USPR000576 Albemarle Corporation Kings Mountain 2022 Pre Feasibility Study-GIS\04 CAD\20240619_Simplified SiteMap\Site Map_Rev 8—Silt Fencing_Linked.dwg SRK Consulting(U.S.), Inc. Erosion and Sediment Control Plan Template—Kings Mountain Page 11 3 Construction Schedule Construction at the Project will be significant and are still in the feasibility stage when this ECP was developed. The individual stages of the Project are described in the Kings Mountain surface water management plan version 2.0 at the time this document was prepared (SWMP) (SRK, 2024) and are summarized below: • Stage A: Early Works and Pre-Development: Construction activities that are planned prior to the start of mine development • Stage B: Development: Construction activities that are planned during mining but prior to lithium production • Stage C: Mining: phased development of the pit that will take place during active mining • Stage D: Closure: closure activities that will commence upon the completion of lithium production Individual ECPs for the various facilities of the mine have or will be provided as the necessary information is developed. This document addresses the ECP for the construction of the OSFs during Stage B, which will be required prior to the development of the RSFs and subsequent mine development. MH/DH April 2024 SRK Consulting(U.S.), Inc. Erosion and Sediment Control Plan Template—Kings Mountain Page 12 4 Planned Erosion and Sedimentation Control Practices Sediment and erosion control practices will be implemented at the site for OSFs as they are developed during Stage B of the Project. The sediment and erosion control features, including the non-contact discharge structures around the OSFs will be permanent and will remain after the Project enters the post-closure phase. Other features, such as the sediment control basins and outlet works associated with discharges from the OSFs,will be in use during the operational period of the mine, approximately 10 years when the development stage is included. Permanent and operational features of the ECP for the OSFs will be implemented as they are constructed during the development phases of the Project and are described in detail below. Additional temporary practices are recommended for the individual components as necessary during their initial construction until vegetation has been established. • Removal and stockpiling of growth media within the footprint of the OSFs and associated infrastructure • Installation of silt fences at the toe of any fill slope until vegetation has been established • Stabilization and revegetation of the slopes and grading associated with native ground • Temporary sediment controls at the outlet of the sediment ponds until the outlet structures are completed Specific practices numbers identified in the erosion and sediment control practices reference the North Carolina Erosion and Sediment Control Planning and Design Manual (NCCCC) (2013), Chapter 6, Practice Standards and Specifications. 4.1 Permanent Development and Operational Stage Practices During the development stage of the Project, surface water management structures will be developed to control flows and sediment during the life of the Project (operational) or during operations and through the post-closure (permanent). These controls are shown in the surface water features drawings include with version 2.1 of the SWMP that this document is supporting. Temporary controls will be removed or reconfigured once they have been supplanted by the operational or permanent surface water controls. Figure 2-1 above shows silt fence locations recommended for temporary sediment control practices required until more permanent controls are implemented. Appendix E-1A includes supporting calculations for the erosion control measures. Discharge from the OSF facilities will be controlled through the release of impacted water at designated points only as much as possible. Those designated points are labeled on Figure 2-1 for the OSFs discharges presented in this Addendum, as well for the other discharges associated with the Kings Mountain Project. 4.1.1 Permanent Sediment Control Ponds Permanent sediment basins are designed to serve areas larger than 5 ac and remain in function for longer than 1 year. Three permanent sediment ponds (Sediment Ponds 62, 63, and 64) are required for the development of the OSFs during the Project. The Sediment Ponds will receive non-contact water from the disturbed and undisturbed natural soils and runoff from the overburden material both prior to and after the surfaces being revegetated after placement. Non-contact runoff collected by these MH/DH April 2024 SRK Consulting(U.S.), Inc. Erosion and Sediment Control Plan Template—Kings Mountain Page 13 channels will be diverted around the OSFs into the sediment ponds prior to release the waters into the existing South Creek as it passes through the Project area. Table 4.1: Summary of Sediment Ponds Characteristics Storage (cubic Design Surface Skimmer Name Contributing Disturbed feet ft3 x 1,000 Area(square Depth Size Area(ac) Area(%) Required Design feet(ft2)x (ft) (Float/ 1,000 Orifice Sed_Pond 1 (described in 112 90% 181.4 417 52.5 11 8"/6.5" SWMP V2.0 Sed_Pond_62 9.3 13% 16.7 20.4 20.7 4 3"/3" Sed_Pond_63 30.6 27% 55.1 57.0 22.6 6 6"/5" Sed_Pond_64 13.3 54% 23.9 24.8 13.4 4 6"/3.5" Source:SRK,2024 4.1.2 Sediment Control Pond 1 (Skimmer Sediment Basin-Practice 6.64) Sediment Pond 1 will be constructed as a skimmer sediment basin at the downstream portion of the non-contact water channel system to manage flows from the pit perimeters, haul roads, NPI areas and OSF-2. All runoff from the OSF-2 associated with Addendum 2.1 will be conveyed to Sediment Pond 1 before being released into Kings Creek. The primary outlet for Sediment Pond 1 will be a Floating skimmer with an emergency outlet culvert as shown in Detail X of Figure XX. 4.1.3 Sediment Control Ponds 62 and 63 (Skimmer Sediment Basin-Practice 6.64) Sediment Ponds 62 and 63 will be constructed as skimmer sediment basins at the downstream portion of the non-contact water channel system associated with OSF-1.All runoff from the OSF-1 associated with Addendum 2.1 will be conveyed to either Sediment Pond 62 or Sediment Pond 63 before being released into an unnamed tributary of South Creek. The primary outlet for Sediment Ponds 62 and 63 will be Floating skimmers with an emergency overflow weir. 4.1.4 Sediment Control Pond 64 (Skimmer Sediment Basin-Practice 6.64) Sediment Pond 64will be constructed as a skimmer sediment basin at the downstream portion of the non-contact water channel system associated with OSF-3. All runoff from the OSF-1 associated with Addendum 2.1 will be conveyed to Sediment Pond 64 before being released into an unnamed tributary of South Creek.The primary outlet for Sediment Pond 64 will be Floating skimmers with an emergency overflow weir. 4.1.5 Permanent Grass-Lined Channels (Practice 6.21 and Practice 6.30) Permanent non-contact diversions channels will be constructed to route non-contact flow through the Project area, as shown on Figure 4.1. Where calculations indicate that grass-lined channels will have adequate erosion resistance, these channels will be stabilized and revegetated as part of the channel construction. 4.1.6 Permanent Riprap-Lined Channels (Practice 6.21 and Practice 6.31) Permanent non-contact diversions channels will be constructed to route non-contact flow through the Project area, as shown on Figure 4.1. Where calculations indicate that riprap-lined channels will be MH/DH April 2024 SRK Consulting(U.S.), Inc. Erosion and Sediment Control Plan Template—Kings Mountain Page 14 required to provide adequate erosion resistance, these channels will be constructed with riprap channel armoring. Emergency overflow spillway weirs will be designed as permanent riprap channels. 4.1.7 Permanent Outlet Protection Level Spreader (Practice 6.40) Permanent pond Sediment Ponds will discharge into either South or Kings Creek using a skimmer as well as an emergency spillway. The outlet pipe from the skimmer and the discharge from the emergency spillway will use a riprap apron leading to a level spreader at the discharge point into the downstream drainage to minimize erosion. 4.1.8 Operational Dust Control (Practice 6.84) Haul traffic on dirt roads between the mine facilities will be ongoing during the mine development, operations, and closure activities and will require regular application of water for dust control. Dust control water will be supplied by the pit dewatering forcemain prior to discharging into WSB-1 or directly from WSB-1 if needed. Air monitoring will be implemented at the site to evaluate the effectiveness of the dust control and adjust sprinkling application rates as necessary to meet Mine Safety and Health Administration (MSHA) guidelines. 4.1.9 Permanent Revegetation Practices During development, the OSFs will be graded to final surface configuration. When placement is complete, the surfaces will be revegetated as described below: 4.1.10 Closure Surface Grading (Practice 6.02) Final OSF surfaces will be constructed at an overall slope of 3H:1V. 4.1.11 Closure Surface Topsoiling, Roughening, and Revegetation (Practices 6.04, 6.03, and 6.11) OSF Surfaces that will remain at closure will consist of overburden soils and are not anticipated to require the addition of growth media.The surfaces will be roughened prior to permanent seeding using a vegetation plan developed and validated for the mine. MH/DH April 2024 SRK Consulting(U.S.), Inc. Erosion and Sediment Control Plan Template—Kings Mountain Page 15 5 Maintenance Plan Regular maintenance practices are important to prevent adverse negative impacts to the environment. Routine inspections of all sediment control facilities will be conducted at least once per week and after every rainfall event that results in observable runoff. An inspection report template will be prepared. Based on the observations, the following activities will be conducted. • Sediment ponds: o All erosion and sediment control measures, including sediment ponds, seepage ponds, check dams, silt curtains will be checked for stability and operation. Any needed repairs or adjustments will be implemented immediately. o The three permanent sediment basins associated with the OSF ECP: Sediment Pond 62, Sediment Pond 63 and and Sediment Pond 64 will be cleaned out when the sediment accumulation reaches 50% of the available storage. For each facility the cleanout level will be pre-determined in the inspection report. o Floating trash and debris will be removed. o Vegetation at the top and faces of the embankment will be removed. o All outlet structures from the sediment ponds will be inspected for clogging and/or structural damage. Debris will be removed, and any repairs needed will be done immediately. Outflow locations will be inspected to make sure tailwater conditions are not impeding discharge from the pond. • Riprap channels: o Riprap channels will be inspected at least once a year and after every major storm event for displaced stones, slumping and erosion at edges, particularly in steeper segments. o Woody vegetation will be removed from the riprap annually to avoid potential impacts associated with the roots, such as dislodgement of the rocks • General guidance: o Placement of field markers to denote areas of concern and in need of repairs or maintenance. o A plan to access appropriate riprap (e.g., on site stockpiles) will be in place, to allow for timely repairs of eroding channels. o For each inspection, the inspector should bring a copy of the as-built drawings to mark potential corrections and problem areas. The marked-up drawings will be stored digitally so that confirmation of the works needed were completed in subsequent inspections. The reports will also include photographic records to document the following: - Vehicle access - Overview of facility - Overview of spillway - Overview of discharge infrastructure - Upstream view of the facility - Downstream view of the facility MH/DH April 2024 SRK Consulting(U.S.), Inc. Erosion and Sediment Control Plan Template—Kings Mountain Page 16 6 Detail Drawings and Specifications for Practices Specified References have been made to specific sections of the NC Erosion and Sediment Control Manual. Detail drawings and specifications are provided on the included Figures C3.01, C3.02, C3.03 and C3.04. Detail D on Drawing C3.03 shows a typical Sediment Pond plan and profile with riser and skimmer outlet. Detail A on Drawing C3.04 presents sections through Sediment Ponds 62 and 63, associated with OSF-1. Detail B on Drawing C3.04 presents a section through Sediment Ponds 64, associated with OSF-3 Detail C on Drawing C3.01 shows a section through a typical permanent riprap-lined channels (Practice 6.21). Dimensions for the channels are shown in the table adjacent to the detail. Detail D on Drawing C3.01 shows the permanent and operational outlet stabilization structure(Practice 6.41). MH/DH April 2024 A B C D E F G H I J NON CONTACT WATER CHANNEL DIMENSIONS BOTTOM WIDTH Depth Bottom Sideslope Bed Slope D50 (in.) Channel ID (ft) Width (ft) (xH:1V) (ft/ft) Revetement Level Spreader (not to scale) NC-P62 Steep 2.00 8 2 0.085 Riprap 10 NC-P62 Mod 2.00 8 2 0.049 Riprap 8 \/ NC-P62 Low Grass-lined �.- �j\ 2.00 12 2 0.01 (•. Rr ►�.�+•vlwt- ��• �i,� DEPTH NC-P63 SteepRiprap 2.00 12 2 0.084 p p 10 l ,his, .��.• �,...- NC-P63 Mod 2.00 12 2 0.061 Ri ra 12 Ve '"' "� ' ' �`<< �.,��'N•'.►""�'' ..: Transition p p 9 etated 2.50 12 2 0.01 diversion � �� •� •�- "� w,••••` NC-P63 Low Grass-lined �`."'�"'Yy+� ys�''•f, "`"`;; �• "' to 0 grade NC-P64 Steep 2.50 12 2 0.166 Riprap 16 �'ek k- ^�" �� J ''`�• 4• , .•� " GRASS LINED CHANNEL NC-P64 Mod 2.50 12 2 0.059 14 Riprap 14 �', 1'11+h�awt,�;,� 3 ,, ��^• �1` l ,,1�►• SEE TABLES NC-P64 Low 3.00 12 2 0.01 ►'� �....`4.,.v- '�-`I �. " `�" , �� ►�'' �► ��.. ,fir 1�� BELOW FOR Grass-lined ; `,Si�+ ��'�'' „�,."tl• :Q ,..4; / � . ` �'" CHANNEL NC-P65 Steep1 2.00 10 2 0.136 Riprap 14 A'�s--4L :;+ �.�' y1'' "''�.'•""� '• v �� 45�. y w \"' ►fit' DIMENSIONS NC-P65 Steep2 2.00 10 2 0.086 Riprap 10r �,. �A�, .�4,�,.1., ;*` ,:� �""---`f a `' � ,� ,,' �' .��`• ' f�. NC-P65 Mod 2.00 10 2 0.036 Riprap 6 ' �.�' ;�� + ,):,'+ 'At, I ''t`• \ /ram ' 'k%b RIPRAP SIZE ,+p• „1• + k "' ' ' �.' „4 BOTTOM WIDTH 2.50 10 2 0.01 ��'^ 1"r" �r•"� '14. ,k"� ;• +A '`j�,. ► �w " ' , Ha Stabilized NC P65 Low Grass-lined � ti�� ,u• +�� >.d•• .•� .��. „fh►• � ,��• M� (SEE TABLE) ,a; ,vMl• �,. slope NC-P66a Steep 2.00 8 2 0.062 Riprap 6 ,1. ' �►�' �� '' 1n •1• �v a� �"• NC-P66a Mod 2.00 8 2 0.031 Riprap 6 Stable i � . �`' ,�,? Y. `+ ` /'� SIDE undisturbed ,. 1� d�.b �t. (1' „l,- 1 , ,. � SLOPE NC-P66a Low 2.00 8 2 0.0081 Grass-lined Outlet �I, u,. µ�, %"" '•-� �X' j�, V. "I' .a"' �1 DEPTH i NC-P67 2.00 0 2 0.052 Grass-lined 1,.1i wl, ,. 1,• t•. '�` ii..,l.. �' I r)```� \.11 �'' �`` off,.. ;0 1 0 0 NC-P68 Steep 2.00 0 2 0.09 Riprap 9 `l' n�, v.ia Ali, NC-P68 Mod 2.00 0 2 0.045 Grass-lined ��I w�l'" `� ��'• ' \u. �''' �� `� ,� NC-P69 Steep 2.00 8 2 0.117 Riprap 9 �' k"' �'� wlr.. +„ xl`�'• ti, „l NC-P69 Mod 2.00 8 2 0.069 Riprap 8 k�• +' �5�� .4• �� .1 ,Wt n" ti+� '��' 101, FILTER FABRIC NC-P69 Low 2.00 8 2 0.017 Grass-lined 1 �� .A • �'• r I'�`` 11`` +� RIPRAP THICKNESS 1.5X �, � �, �l�• .a�.. 1 �+. w RIPRAP D co NC-P66b Steep 2.00 8 2 0.081 Riprap 10 + t��' � ,,� wi`` w'• NC-P66b Mod 2.00 8 2 0.031 Riprap 6 ( �� "' �, ��• Its.• l„' �+� RIPRAP CHANNEL NC-P66b Low 2.00 8 2 0.02 Grass-lined NC-DV6 Mod 4.00 0 2 0.044 Riprap 12 Figure 6.40a Level spreader is designed to disperse small volumes of concentrated flow across stable slopes. NC-DV6 Low 5.00 0 2 0.008 Grass-lined C TYPICAL CHANNEL DETAIL C3.01 NOT TO SCALE Cross Section Material Variable stapled in {glace 6 � I11101 rein f Level lip � 0 o spreader --� `._., r l = , Buried min 3 v J WI Figure 6.44b Detail Of level spreader cross Section- CA m O O W PSOURCE: Erosion and Sediment Control Planning and Design Manual, North Carolina Department of Environmental and Natural Resources W W Cn J_ Q W coo o B TYPICAL LEVEL SPREADER DETAIL AND SECTION U00 La C3.O1 NOT TO SCALE LO 0 C) O Cn B o �� O� B Q �� x C3.01 0 o O C3.01 C�RvP DIA. ;I 11,„III-III '_ ` III=1 I I I I 1-1 i I- LL o 0 0 0 0 -III-I �� - III-III=1 - ROAD/BERM ARMOR 111-1 11-111=111= _ - - - - - SEE TABLE o�o � � -III-I 11=1 11=1 11=1 11=1 I IJ I IJ I I-1 I I-1 I I-1 I I-1 I I o 0 0 oQU ooU o 0 � o 0 a FILTER FABRIC ao y o SECTION D-D N RIPRAP CLASS B POND '" 0�0�0 O SEE DETAIL C ON THIS SHEET = FOR RIPRAP SPECIFICATIONS \/ LEVEL of �\\�\//\y/ / MAN co ////j i//i PLAN /\\�\\�\��..� .. 40% TYPICAL OUTLET PROTECTION �' /%\"/ �, �,�\,�\\r �\,�\,/\\,/\\//\ o DISCHARGE TO D STABILIZATION DETAILNATURAL DRAINAGE ,� C3.01 NOT TO SCALE FILTER FABRIC \ � \\�\\\\\ ---------- N No TOP OF BERM cli 3 3 0 /N/ LEVEL SPREADER RIPRAP CLASS B 1� \\�/ SEE DETAIL D, SHEET C3.01 25�\�\i�\i\\j/\\\/�\j/�\j/�//�/� Q FILTER FABRIC 0 O U a E POND SPILLWAY DETAILS Q C3.O1 NOT TO SCALE Q0 C) 0 0 0 a- A PREPARED FOR CLIENT REVIEW DPH DPH 12/15/2023 ISSUED FOR: DPH DPH 3/21/2024 PERMIT - consulting A\\ ALBEMARLE � DPH 6/25/2024 DRAWING TITLE: 0 DRAFT SURFACE WATER CHANNEL PLANS U IF THE ABOVE BAR SURFACE WATER CHANNEL Y DOES NOT MEASURE 1 INCH, DESIGN: DRAWN: REVIEWED: c��n PREPARE PREPAREP FOR CLIEN f�FgVWINGSCALEISALTERED MEH DLB JLH KINGS MOUNTAIN MINING DETAIL SHEET (1 OF 4) CHECKED: APPROVED: DATE: DPH DPH 6/25/2024 N DRAWING NO. DRAWING TITLE NO. DESCRIPTION CHK'D APP'D DATE DRAWING NO. SHEET REVISION NO. 0 REFERENCE DRAWINGS REVISIONS PROFESSIONAL ENGINEERS STAMP FILE NAME: USPR000576-C3.01-C3.02 DETAIL SHEETS REVOOB2_EL.dwg SRK JOB NO.: USPR000576 C3.01 30 of 33 B U A B C D E F G H I J SEE TABLES ON SHEET C3.01 FOR CHANNEL RUNOFF FROM DIMENSIONS HAUL ROAD 80 FT TYP NATURAL GROUND NON—CONTACT WATER DITCH SAFETY BERM 1.5 (TYP.) HAUL ROAD 80 FT TYP SEE TABLES ON � SAFETY BERM F SHEET C3.01 FOR Fx/S NC C 3 DEPTH SAFETY BERM CHANNEL C Ti GRO Tc� �. 4 1 DIMENSIONS SAFETY BERM RUNOFF AND SEEPAGE WASTE ROCK �1 -RCN �5 FT MIN I �---WIDTH� \�/,\� 2% TYP.) CONTACT WATER DITCH FROM WASTE ROCK 3 e)kle�AoGGVOv ALTERNATE SECTION �iV4/4/ 4/4 ��CATCH BENCH 4/�4j�4j�4j�4j�4j4 2% Typ.) IF HAUL ROAD IN FILL V�444�` 1 4 DE TH 4��4��4/�� 4��4��44V�4V�/ I I 3 WII TYPICAL HAUL ROAD SECTION D TYPICAL HAUL ROAD SECTION IN FILL ('A' ADJACENT TO ROCK STORAGE FACILITY c3.O2 SCALE: 1"=5' M C3.O2 SCALE: 1"=5' SEE TABLES ON SHEET C3.01 FOR RUNOFF FROM CHANNEL HAUL ROAD 80 FT TYP NATURAL GROUND DIMENSIONS NON—CONTACT WATER DITCH SAFETY BERM SEE TABLES ON 4 4 SHEET C3.01 FOR CHANNEL F'rSTNCTOc3 1 DEPTH �1 SAFETY BERM DIMENSIONS OFF FROM 4 NON—CONTACT WATER DITCH NAT RALGROUND 5 FT MI �WIDTH� V��V� Na��Go�No EX�� GGR ALTERNATE SECTION DEPTH IF HAUL ROAD IN FILL /�4/ // 4 3 I D TH LO B TYPICAL HAUL ROAD SECTION IN CUT C3.O2 SCALE: 1"=5' 3 J W N Ca O O Uj W H W W _ Cn SEE TABLES ON SHEET C3.01 FOR o CHANNEL o DIMENSIONS HAUL ROAD 80 FT TYP SEE TABLES ON SHEET C3.01 FOR co RUNOFF FROM CHANNEL 0 NATURAL GROUND NON—CONTACT WATER DITCH SAFETY BERM DIMENSIONS RUNOFF FROM PERIMETER ROAD 35 FT TYP r� NATURAL GROUND SAFETY BERM 0 1� DEPTH �1 SAFETY BERM NON—CONTACT WATER DITCH SAFETY BERM ry IL 3 4 ' 4 2% TYP.) 2% ------- -Willi T �444�4� 2% TYP.) 4�S��iypl4l DEPTH �1 �/4�/4� 4 4 .L T7 O�R O'Cti /��4 4 44 3 C14 / � � 1 3 �G� �5 FT MIN-► do �—WIDTFYf4� �j� co �X(EN0G GRO��O ALTERNATE SECTION IF PERIMETER ROAD IN FILL F TYPICAL PIT RIM ROAD SECTION a, C3.O2 SCALE: 1"=5' 00 N 0 U 0 TYPICAL HAUL ROAD zi ( C' SECTION IN PARTIAL CUT CD C3.O2 SCALE: 1"=5' 0 U) a a .N rn m - m d N N 0 N C C 7 O N O C Y c 0 `O a `O O U m m E am Q 0 LO CD 0 0 0 A PREPARED FOR CLIENT REVIEW DPH DPH 12/15/2023 ISSUED FOR: Z) B PREPARED FOR CLIENT REVIEW DPH DPH 3/21/2024 PERMIT r kconsulting J\ ALBEMARLE DRAWING TITLE: N SURFACE WATER CHANNEL PLANS 0 0 U IF THE ABOVE BAR DRAFT SURFACE WATER CHANNEL ry DOES NOT MEASURE 1 INCH, DESIGN: DRAWN: REVIEWED: THE DRAWING SCALE IS ALTERED MEH DLB JLH KINGS MOUNTAIN MINING DETAIL SHEET (2 OF 4) CHECKED: DPH APPROVED: DPH DATE: 3/21/2024 u, DRAWING NO. DRAWING TITLE NO. DESCRIPTION CHK'D APP'D DATE DRAWING NO. SHEET REVISION NO. REFERENCE DRAWINGS REVISIONS PROFESSIONAL ENGINEERS STAMP FILE NAME: USPR000576-C3.01-C3.02 DETAIL SHEETS REVOOB2_EL.dwg SRK JOB NO.: USPR000576 C3.02 31 of 33 B U A B C D E F G H I J HAUL ROAD WIDTH 80 FT. TYP. SAFETY SAFETY BERM 2% BERM TYP.� 3 HAUL ROAD H51 } CENTERLINE EL. 917 FT. N HAUL ROAD FILL MULTI-PLATE ARCH CULVERT SEE DETAIL C3.03 EXISTING SOUTH CREEK CHANNEL M CULVERT INLET ON NATURAL STREAM BOTTOM EXISTING SOUTH EXISTING CHANNEL INVERT 0 EL. 867 FT. RESTORED ORIGINAL CHANNEL BED a v�o�Lvr>� � '; � �� ,r��' � � - � CREEK CHANNEL CULVERT LENGTH 461 FT. \ CULVERT OUTLET ON EXISTING CHANNEL INVERT EL. 857 FT. HAUL ROAD SURFACE MULTI-PLATE ARCH CULVERT AT HAUL ('A_" ROAD H51 CROSSING SOUTH CREEK / C3,Q3 SCALE: 1"=20' HAUL ROAD FILL LO MULTI-PLATE ARCH CULVE STEEL POSTS STONE PAD SELECT FILL PER DESIGN FLOW DEPTH 100-YR,24-HR BELOW SKIMMER STORM EVENT-4.2 ft RISE 10.76 ft SKIMMER EMBANKMENT DEPTH 2 24FLOW HR STORM EVENT / ORIGINAL GROUND PLASTIC SLOPE ORIGINAL GROUND J FOOTER DRAIN PIPE remove RISER NI STRUCTURE Ca 0 0 0 0 0 0 o PERMANENT DITCH RESTORED ORIGINAL w CHANNEL BED Ww> 1 = SPAN 27.3 ft ft U) wROAD p WIDTH N O co MULTI-PLATE ARCH CULVERT c c STONE ENERGY o C3.03 C3.03 M DISSIPATOR B AT SOUTH CREEK CROSSING DETAIL APPROACH CORRUGATED STEEL DISCHARGE BELOW SKIMMER STONE PAD C3.03 SCALE: 1"=5' CHANNEL PIPE(CSP)CULVERT CHANNEL 0 ry COIR FIBRE BAFFLES U) ROPE EMERGENCY o SPILLWAY 0 WOOD STAKE OR cli METAL POST INLET PROTECTION SEE DETAIL C3.01 OUTLET PROTECTION co SEE DETAIL C3.01 PLAN VIEW o- P PLAN VIEW 00 N 0 TOP OF EMBANKMENT U 0 0 TRASH BACK 1 SKIMMER Z iii-- =l I=1T=I I=I I— o RISER - f EMERGENCY SPILLWAY o ROAD STRUCTURE Q =I 1 I—I I I—I —I I I—I I I—I I I—III=III=Tf=I WIDTH m- 2 5 —I I=III—III—III—I I I=III=I I I=I I I=III=I I I=I I I — 2.5 I I—III—III=1 I I=1 I I=1 I I=1 I I=1 I I=1 I I=1 I I=1 I I=1 I I=1 I I—III—I w t III—III—I11=III=III=III=III=III=III=11 I=III=1 I=I I I=1I1=I I=I I I— 1 BARREL PIPE Aw - - I=1 I-1 I-1 I-1 I-1 I-1 11=1 11=1 1=1 1=1 11=1 11-1 I, I I� I II i II I II II — Y � =111=—=—IJ�I 11=1 11=1 11=1 11=1 11=1 11=1 11=1 11=1 11=1 11=1 I I - - �I I_I N SAFETY If 4'¢M//V _ — — — — — — — — — — STABILIZED OUTLET Ca BERM / ROAD FILL APPROACH ti CHANNEL CORRUGATED STEEL ��- j�� /a - N �� PIPE(CSP)CULVERT GRADE— DISCHARGE �� FMF��1 �� No �V /% CHANNEL C � CLASS B STONE PAD ANTI-SEEP COLLAR DIAMETER (4'X 4'X 1'MIN.) o (SEE TABLE) INLET PROTECTION D ANTIPLOTATION BLOCK CUT-OFF TRENCH U) SEE DETAIL C3.01 OUTLET PROTECTION 2'DEEP SEE DETAIL C3.01 SECTION C-C 0 a SECTION VIEW `o O LD C TYPICAL CULVERT DETAIL D TYPICAL SEDIMENT BASIN PLAN AND SECTION a C3.03 NOT TO SCALE C3,03 NOT TO SCALE LO CD 0 0 0 A PREPARED FOR CLIENT REVIEW DPH DPH 12/15/2023 ISSUED FOR: Z) B PREPARED FOR CLIENT REVIEW DPH DPH 3/21/2024 PERMIT ;rkconsulting J\ ALBEMARLE DRAWING TITLE: N SURFACE WATER CHANNEL PLANS 0 U IF THE ABOVE BAR DRAFT SURFACE WATER CHANNEL ry DOES NOT MEASURE 1 INCH, DESIGN: DRAWN: REVIEWED: THE DRAWING SCALE IS ALTERED MEH DLB JLH KINGS MOUNTAIN MINING DETAIL SHEET (3 OF 4) CHECKED: DPH APPROVED: DPH DATE: 3/21/2024 u, DRAWING NO. DRAWING TITLE NO. DESCRIPTION CHK'D APP'D DATE DRAWING NO. SHEET REVISION NO. REFERENCE DRAWINGS REVISIONS PROFESSIONAL ENGINEERS STAMP FILE NAME: USPR000576-C3.01-C3.02 DETAIL SHEETS REVOOB2_EL.dwg SRK JOB NO.: USPR000576 C3.03 32 of 33 B U A B C D E F G H I J D TYPICAL SEDIMENT BASIN C3.03 PLAN AND PROFILE x O k O O — OVERFLOW SPILLWAY SEE DETAIL C3.01 / 840•D0 TLAND BU ER ZONE r7 _ -- ----- rn O Z SKIMMER D ------------ O Z' O O U W 0 �A �,V -- 920.00 -- O� M OVERFLOW SPILLWAY E TYPICAL SEDIMENT BASIN SEE DETAIL C3.01 3.03 PLAN AND PROFILE \ N 0 0 Ln \ `' S50 0 O I O WETLAND BUFFER k0 SKIMMER ZONE O i --------------------- 0 00 2 2� O20 0 j OVERFLOW SPILLWAY E SEE DETAIL C3.01 D TYPICAL SEDIMENT BASIN C3.03 PLAN AND PROFILE i 2 0 1 BERM 2 > 1 POND 2 EXISTING GROUND w BOTTOM _ 1 ml SECTION C-C' j OSF-1 SLOPE WETLAND BUFFER � BERM BOUNDARY w 1 POND BOTTOM B WETLAND BUFFER OSF-3 SEDIMENT PONDS PLAN AND PROFILE Q SECTION A-A' BOUNDARY 1C,3,04 1" = 30' w 0 N O M U 0 M U BERM LO 2 1 2 2 EXISTING GROUND o BOTTOM ----- r <Un SECTION B-B' g WETLAND BUFFER 0 BOUNDARY v N a) LL 0) A OSF-1 SEDIMENT PONDS PLAN AND PROFILE co 00 C3.04 1" = 30' 0 U 0 0 2-o 2 0 0 M 0 U) a a .N rn as a) LL m d N N O N C C 7 O N C Y c 0 p `o a `o O U m m E m Q LO CD 0 0 0 A PREPARED FOR CLIENT REVIEW DPH DPH 12/15/2023 ISSUED FOR: Z) DPH DPH 3/21/2024 PERMIT Q z srkconsulting0 DPH 6/25/2024 J� ALBEMARLE DRAWING TITLE: U) SURFACE WATER CHANNEL PLANS r_ C U IF THE ABOVE BAR DRAFT SURFACE WATER CHANNEL aryi FOR CLIEN MEH DLB JLH DOES NOT MEASURE 1 INCH, DESIGN: DRAWN: REVIEWED: PEPARE l / WINGSCALEISALTERED KINGS MOUNTAIN MINING DETAIL SHEET (4 OF 4) CHECKED: DPH APPROVED: DPH DATE: 6/25/2024 u, DRAWING NO. DRAWING TITLE NO. DESCRIPTION CHK'D APP'D DATE DRAWING NO. SHEET REVISION NO. REFERENCE DRAWINGS REVISIONS PROFESSIONAL ENGINEERS STAMP FILE NAME: USPR000576-C3.01-C3.02 DETAIL SHEETS REVOOB2_EL.dwg SRK JOB NO.: USPR000576 C3.04 33 of 33 B U SRK Consulting(U.S.), Inc. Erosion and Sediment Control Plan Template—Kings Mountain Page 17 7 Vegetation Plan In accordance with the North Carolina Application for a Mining Permit, a reclamation plan must include plans for year-round seeding, including the time of seeding and the amount of seed, type of seed, fertilizer, lime, and mulch per acre. The recommendations must include general seeding instructions for both permanent and temporary revegetation. A preliminary seed mix and schedule provided by SWCA is included in Table 7.1. Table 7.1: Preliminary Seed Mix Composition and Schedule Seed Mix Type Seeding Dates Seeding Rates NC Steep Slope Mix ERNMX-310 All dates 45 Ibs/acre Native Habitat Strip Mine Mix ERNMX-111 All dates 20 Ibs/acre Native Steep Slope w annual rye(ERNMX-181) Feb 15-Aug 15 60 Ibs/acre Native Steep Slope w grain rye ERNMX-181-2 Aug15-Feb 16 75 Ibs/acre Source:SRK,2023 Temporary cover species for erosion control would include: • Brown Top Millet: Feb 15-Aug 15 20 lb/acre • Annual Rye Grain: Aug 15- Feb 15 30 lb/acre No fertilizer is recommended at the site due to the success of volunteer regrowth seen during site visits. Seed would be procured from Ernst Conservation Seeding or other approved seeding contractor. Wildlife habitat is typically established by creating ecosystems of native species, and reshaping landscapes to create suitable habitat. Monitoring and measurement criteria for vegetation and wildlife success will be developed as mine plans progress. MH/DH April 2024 SRK Consulting(U.S.), Inc. Erosion and Sediment Control Plan Template—Kings Mountain Page 18 8 Supporting Calculations Hydrological and hydraulic calculations were primarily conducted using WinTR-55 models developed for the project. Appendices E-1A ("Runoff Estimation") and E-11B ("Channel Design") present a summary of hydrological and hydraulic calculations and modeling results used for the design of erosion and sediment control measures.Appendix E-1 C presents a summary of calculations conducted for the design of the sediment ponds with skimmers. MH/DH April 2024 SRK Consulting(U.S.), Inc. Erosion and Sediment Control Plan Template—Kings Mountain Page 19 9 References North Carolina Sedimentation Control Committee, North Carolina Department of Environmental and Natural Resources, and the North Carolina Agricultural Extension Service. Erosion and Sediment Control Planning and Design Manual, May 2013. Surface MINING Manual (1996). State of North Carolina, Department of Environment, Health and Natural Resources, February 1996. SRK, 2024. Conceptual Report Closure Plan Kings Mountain Mining Project September 2024 SWCA, (2023a). Baseline Soil Sampling and Analysis for the Albemarle Kings Mountain Lithium Mining Project Cleveland County, North Carolina, prepared for Albemarle U.S., by SWCA Environmental Consultants, Kelley House, Andrew Harley Broomfield, Colorado, April 2023. SWCA, (2023b). Biological Resources Summary Report for the Kings Mountain Lithium Mine, Cleveland County, North Carolina Interim Draft, prepared for Albemarle U.S., by SWCA Environmental Consultants, Colorado, April 2023. USDA Agricultural Research Service (2019). Small Watershed Hydrology (WinTR-55). United States Department of Agriculture. Model. https://hdl.handle.net/l0113/AA22714 MH/DH April 2024 SRK Consulting(U.S.), Inc. Erosion and Sediment Control Plan Template—Kings Mountain Page 20 Disclaimer The opinions expressed in this Report have been based on the information supplied to SRK Consulting (U.S.), Inc. (SRK) by Albemarle Corporation (Albemarle). These opinions are provided in response to a specific request from Albemarle to do so, and are subject to the contractual terms between SRK and Albemarle. SRK has exercised all due care in reviewing the supplied information. Whilst SRK has compared key supplied data with expected values, the accuracy of the results and conclusions from the review are entirely reliant on the accuracy and completeness of the supplied data. SRK does not accept responsibility for any errors or omissions in the supplied information and does not accept any consequential liability arising from commercial decisions or actions resulting from them. Opinions presented in this report apply to the site conditions and features as they existed at the time of SRK's investigations, and those foreseeable. These opinions do not necessarily apply to conditions and features that may arise after the date of this Report. Copyright This report is protected by copyright vested in SRK Consulting (U.S.), Inc. It may not be reproduced or transmitted in any form or by any means whatsoever to any person without the written permission of the copyright holder, SRK. MH/DH April 2024 SRK Consulting(U.S.), Inc. Erosion and Sediment Control Plan Template—Kings Mountain Appendices Appendix E-1A: Runoff Estimation for the Kings Mountain Mining Project MH/DH April 2024 BMK USPR0576 Albemarle KM OSF-1 Hydrology Cleveland NOAA-B County, North Carolina Storm Data Rainfall Depth by Rainfall Return Period 2-Yr 5-Yr 10-Yr 25-Yr 100-Yr 500-Yr 9999-Yr (in) (in) (in) (in) (in) (in) (in) -------------------------------------------------------------------------------- 3.63 4.56 5.3 6.32 7.98 10.1 28.5 Storm Data Source: User-provided custom storm data Rainfall Distribution Type: Type II Dimensionless Unit Hydrograph: <standard> WinTR-55, Version 1.00.10 Page 1 6/24/2024 2:43:49 PM BMK USPR0576 Albemarle KM OSF-1 Hydrology Cleveland NOAA-B County, North Carolina Watershed Peak Table Sub-Area Peak Flow by Rainfall Return Period or Reach 10-Yr 100-Yr Identifier (cfs) (cfs) ---------------------------------------------------------------------------------- SUBAREAS RF1 21.89 42.76 RF2 25.29 49.40 RO1 55.87 140.51 RO2 24.94 60.82 RF3 8.35 15.45 RF4 5.52 9.14 REACHES OUTLET 89.92 218.81 WinTR-55, Version 1.00.10 Page 1 6/24/2024 2:43:49 PM BMK USPR0576 Albemarle KM OSF-1 Hydrology Cleveland NOAA-B County, North Carolina Sub-Area Summary Table Sub-Area Drainage Time of Curve Receiving Sub-Area Identifier Area Concentration Number Reach Description (ac) (hr) -------------------------------------------------------------------------------- RF1 6.46 0.134 71 Outlet RF2 7.30 0.121 71 Outlet RO1 60.90 0.655 59 Outlet RO2 23.12 0.571 60 Outlet RF3 2.01 0.100 75 Outlet RF4 1.00 0.100 85 Outlet Total Area: 100.79 (ac) WinTR-55, Version 1.00.10 Page 1 6/24/2024 2:43:49 PM BMK USPR0576 Albemarle KM OSF-1 Hydrology Cleveland NOAA-B County, North Carolina Sub-Area Time of Concentration Details Sub-Area Flow Mannings's End Wetted Travel Identifier/ Length Slope n Area Perimeter Velocity Time (ft) (ft/ft) (sq ft) (ft) (ft/sec) (hr) -------------------------------------------------------------------------------- RF1 SHEET 100 0.2163 0.150 0.059 SHALLOW 198 0.3110 0.050 0.006 CHANNEL 1608 0.0385 0.040 10.00 12.00 6.473 0.069 Time of Concentration .134 RF2 SHEET 100 0.2120 0.150 0.060 SHALLOW 200 0.3114 0.050 0.006 CHANNEL 1280 0.0381 0.040 10.00 12.00 6.465 0.055 Time of Concentration .121 RO1 SHEET 100 0.0100 0.400 0.443 SHALLOW 1458 0.0383 0.050 0.128 CHANNEL 1273 0.0409 0.050 14.00 24.00 4.210 0.084 Time of Concentration .655 RO2 SHEET 100 0.0100 0.400 0.443 SHALLOW 865 0.0341 0.050 0.081 CHANNEL 853 0.0291 0.050 20.00 20.00 5.041 0.047 Time of Concentration .571 RF3 User-provided 0.100 Time of Concentration 0.100 RF4 User-provided 0.100 Time of Concentration 0.100 WinTR-55, Version 1.00.10 Page 1 6/24/2024 2:43:49 PM BMK USPR0576 Albemarle KM OSF-1 Hydrology Cleveland NOAA-B County, North Carolina Sub-Area Land Use and Curve Number Details Sub-Area Hydrologic Sub-Area Curve Identifier Land Use Soil Area Number Group (ac) -------------------------------------------------------------------------------- RF1 Meadow -cont. grass (non grazed) C 6.46 71 Total Area / Weighted Curve Number 6.46 71 RF2 Meadow -cont. grass (non grazed) C 7.3 71 Total Area / Weighted Curve Number 7.3 71 RO1 Residential districts (2 acre) B 23 65 Woods (good) B 37.9 55 Total Area / Weighted Curve Number 60.9 59 RO2 Residential districts (2 acre) B 12 65 Woods (good) B 11.12 55 Total Area / Weighted Curve Number 23.12 60 RF3 Paved parking lots, roofs, driveways D .31 98 Meadow -cont. grass (non grazed) C 1.7 71 Total Area / Weighted Curve Number 2.01 75 RF4 Paved parking lots, roofs, driveways D .5 98 Meadow -cont. grass (non grazed) C .5 71 Total Area / Weighted Curve Number 1 85 WinTR-55, Version 1.00.10 Page 1 6/24/2024 2:43:49 PM BMK USPR0576 Albemarle KM OSF Hydrology Cleveland NOAA-B County, North Carolina Storm Data Rainfall Depth by Rainfall Return Period 2-Yr 5-Yr 10-Yr 25-Yr 100-Yr 500-Yr 1000-Yr (in) (in) (in) (in) (in) (in) (in) -------------------------------------------------------------------------------- 3.63 4.56 5.3 6.32 7.98 10.1 11.0 Storm Data Source: User-provided custom storm data Rainfall Distribution Type: Type II Dimensionless Unit Hydrograph: <standard> WinTR-55, Version 1.00.10 Page 1 6/24/2024 2:47:21 PM BMK USPR0576 Albemarle KM OSF Hydrology Cleveland NOAA-B County, North Carolina Watershed Peak Table Sub-Area Peak Flow by Rainfall Return Period or Reach 10-Yr 100-Yr Identifier (cfs) (cfs) ---------------------------------------------------------------------------------- SUBAREAS RF1 77.22 150.26 RF2 30.40 59.07 RF3 4.54 12.82 REACHES OUTLET 110.79 218.44 WinTR-55, Version 1.00.10 Page 1 6/24/2024 2:47:21 PM BMK USPR0576 Albemarle KM OSF Hydrology Cleveland NOAA-B County, North Carolina Sub-Area Summary Table Sub-Area Drainage Time of Curve Receiving Sub-Area Identifier Area Concentration Number Reach Description (ac) (hr) -------------------------------------------------------------------------------- RF1 26.45 0.247 71 Outlet RF2 9.44 0.173 71 Outlet RF3 3.39 0.100 53 Outlet Total Area: 39.28 (ac) WinTR-55, Version 1.00.10 Page 1 6/24/2024 2:47:21 PM BMK USPR0576 Albemarle KM OSF Hydrology Cleveland NOAA-B County, North Carolina Sub-Area Time of Concentration Details Sub-Area Flow Mannings's End Wetted Travel Identifier/ Length Slope n Area Perimeter Velocity Time (ft) (ft/ft) (sq ft) (ft) (ft/sec) (hr) -------------------------------------------------------------------------------- RF1 SHEET 100 0.0300 0.130 0.116 SHALLOW 360 0.3000 0.050 0.011 CHANNEL 3120 0.0353 0.035 12.00 14.00 7.222 0.120 Time of Concentration 0.247 RF2 SHEET 100 0.0300 0.130 0.116 SHALLOW 360 0.3000 0.050 0.011 CHANNEL 1458 0.0520 0.035 12.00 14.00 8.804 0.046 Time of Concentration .173 RF3 SHEET 50 0.3000 0.130 0.027 SHALLOW 270 0.3000 0.050 0.008 CHANNEL 343 0.1310 0.045 10.00 15.00 9.528 0.010 Time of Concentration 0.1 WinTR-55, Version 1.00.10 Page 1 6/24/2024 2:47:21 PM BMK USPR0576 Albemarle KM OSF Hydrology Cleveland NOAA-B County, North Carolina Sub-Area Land Use and Curve Number Details Sub-Area Hydrologic Sub-Area Curve Identifier Land Use Soil Area Number Group (ac) -------------------------------------------------------------------------------- RF1 Meadow -cont. grass (non grazed) C 26.45 71 Total Area / Weighted Curve Number 26.45 71 RF2 Meadow -cont. grass (non grazed) C 9.44 71 Total Area / Weighted Curve Number 9.44 71 RF3 Meadow -cont. grass (non grazed) B 1.695 58 Brush - brush, weed, grass mix (good) B 1.695 48 Total Area / Weighted Curve Number 3.39 53 WinTR-55, Version 1.00.10 Page 1 6/24/2024 2:47:21 PM BMK USPR0576 Albemarle KM SSP Hydrology Cleveland NOAA-B County, North Carolina Storm Data Rainfall Depth by Rainfall Return Period 2-Yr 5-Yr 10-Yr 25-Yr 100-Yr 500-Yr 1000-Yr (in) (in) (in) (in) (in) (in) (in) -------------------------------------------------------------------------------- 3.63 4.56 5.3 6.32 7.98 10.1 11.0 Storm Data Source: User-provided custom storm data Rainfall Distribution Type: Type II Dimensionless Unit Hydrograph: <standard> WinTR-55, Version 1.00.10 Page 1 6/24/2024 2:51:12 PM BMK USPR0576 Albemarle KM SSP Hydrology Cleveland NOAA-B County, North Carolina Watershed Peak Table Sub-Area Peak Flow by Rainfall Return Period or Reach 10-Yr 100-Yr Identifier (cfs) (cfs) ---------------------------------------------------------------------------------- SUBAREAS RF1 6.96 13.57 RF2 5.64 11.01 RF3 2.67 5.21 RF4 4.03 7.86 RF5 6.45 12.58 RO1 7.01 15.85 RO2 3.85 8.76 REACHES OUTLET 32.42 66.43 WinTR-55, Version 1.00.10 Page 1 6/24/2024 2:51:12 PM BMK USPR0576 Albemarle KM SSP Hydrology Cleveland NOAA-B County, North Carolina Sub-Area Summary Table Sub-Area Drainage Time of Curve Receiving Sub-Area Identifier Area Concentration Number Reach Description (ac) (hr) -------------------------------------------------------------------------------- RF1 1.93 0.100 71 Outlet RF2 1.57 0.100 71 Outlet RF3 .74 0.100 71 Outlet RF4 1.12 0.100 71 Outlet RF5 1.79 0.100 71 Outlet RO1 4.52 0.426 63 Outlet RO2 1.61 0.100 62 Outlet Total Area: 13.28 (ac) WinTR-55, Version 1.00.10 Page 1 6/24/2024 2:51:12 PM BMK USPR0576 Albemarle KM SSP Hydrology Cleveland NOAA-B County, North Carolina Sub-Area Time of Concentration Details Sub-Area Flow Mannings's End Wetted Travel Identifier/ Length Slope n Area Perimeter Velocity Time (ft) (ft/ft) (sq ft) (ft) (ft/sec) (hr) -------------------------------------------------------------------------------- RF1 SHEET 100 0.2500 0.150 0.056 SHALLOW 43 0.3300 0.050 0.001 CHANNEL 803 0.0520 0.035 10.00 12.00 8.579 0.026 Time of Concentration 0.1 RF2 User-provided 0.100 Time of Concentration 0.100 RF3 User-provided 0.100 Time of Concentration 0.100 RF4 User-provided 0.100 Time of Concentration 0.100 RF5 User-provided 0.100 Time of Concentration 0.100 RO1 SHEET 100 0.0020 0.150 0.385 SHALLOW 396 0.0700 0.050 0.026 CHANNEL 472 0.0520 0.035 10.00 12.00 8.741 0.015 Time of Concentration .426 RO2 User-provided 0.100 Time of Concentration 0.100 WinTR-55, Version 1.00.10 Page 1 6/24/2024 2:51:12 PM BMK USPR0576 Albemarle KM SSP Hydrology Cleveland NOAA-B County, North Carolina Sub-Area Land Use and Curve Number Details Sub-Area Hydrologic Sub-Area Curve Identifier Land Use Soil Area Number Group (ac) -------------------------------------------------------------------------------- RF1 Meadow -cont. grass (non grazed) C 1.93 71 Total Area / Weighted Curve Number 1.93 71 RF2 Meadow -cont. grass (non grazed) C 1.57 71 Total Area / Weighted Curve Number 1.57 71 RF3 Meadow -cont. grass (non grazed) C .74 71 Total Area / Weighted Curve Number .74 71 RF4 Meadow -cont. grass (non grazed) C 1.12 71 Total Area / Weighted Curve Number 1.12 71 RF5 Meadow -cont. grass (non grazed) C 1.79 71 Total Area / Weighted Curve Number 1.79 71 RO1 Woods (good) B 2.25 55 Woods (good) C 2.27 70 Total Area / Weighted Curve Number 4.52 63 RO2 Woods (good) B .805 55 Woods (good) C .805 70 Total Area / Weighted Curve Number 1.61 62 WinTR-55, Version 1.00.10 Page 1 6/24/2024 2:51:12 PM SRK Consulting(U.S.), Inc. Erosion and Sediment Control Plan Template—Kings Mountain Appendices Appendix E1-13: Channel Design for the Kings Mountain Mining Project MH/DH April 2024 TABLE A-3a FLOW RESULTS FROM HEC-HMS Albemarle Kings Mountain PFS Archdale Channel Design Date: 6/25/24 PROJECT NO.:USPR000576 I By:GKH Chkd:DPH HMS Run Description 700(Data Range Name:HECHMS_100) V Copy entire HTML Output from Standard Report(Global results ONLY)and paste in cell below: From Win TR-55,manually entered Global Results Summary Hydrologic Element Drainage Area Peak Discharge(AC) (CFS) Time of Peak Volume(AC-FT) OFSI NV-DV6 60.9 140.5 na na OSFI NC-P62 7.3 49.4 na na OSFI NC-P63 29.58 103.56 na na OSF2 NC-P64 26.45 150.26 na na OSF2 NC-P65 9.44 59.07 na na OSF3 NC-P66a 3.4 21.34 na na OSF3 NC-P66b 6.83 45.42 na na OSF3 NC-P67 1.12 7.86 na na OSF3 NC-P68 0.74 5.21 na na OSF3 NC-P69 6.45 29.42 na na Page 1 of 1 SRK Consulting h[tps://srk.sh..p.int.."siW./NAUSPR000576/Internal/0300_Hydrology/_SSP hydrology/020_Prolect data(m*ing)/Hydraulics/BasiuH&H Woftheet 08F Perim June 2024.,Ism 6/25/2024 Table A-4 Channel Hydraulic Calculations Albemarle Kings Mountain PFS SSL \ Date: 6/25/24 Archdale Channel Design 0 SSR By:GKH PROJ NO.:USPR000576 'E 8y,/ 3' Chkd: Apprvd: Channel Design Geo etry Channel Roughness Parameters egmres Left Right Minimum Channel Hydraulic Mannings'n' Mannings'n' HEC HMS Channel Bed Side Side Bottom Channel Curvature Jumpllmpact Riprap for Capacity for Stability Design Storm Element ID Length Slope Slope Slope Width Depth Radius Block Colo Calculation Design Channel (Depth (Velocity Reach Designation IHMS Run for (ft) (ftlft) (HAV) (H:1V) (ft) (ft) (ft) (Jump/Block) Methodology Lining Calculation) Calculation) NC-P62 Steep 100 OSF1 NC-P62 290 0.0850 2.0 2.0 8.0 2.00 0 USACE Steep R Riprap 0.040 0.035 NC-P62 Mod 100 OSF1 NC-P62 665 0.0490 2.0 2.0 8.0 2.00 0 USACE Steep R Riprap 0.040 0.035 NC-P62 Low 100 OSF1 NC-P62 410 0.0100 2.0 2.0 12.0 2.00 0 None G Grass-lined 0.035 0.030 NC-P63 Steep 100 OSF1 NC-P63 150 0.0840 2.0 2.0 12.0 2.00 0 Robinson R Riprap 0.040 0.035 NC-P63 Mod 100 OSF1 NC-P63 730 0.0610 2.0 2.0 12.0 2.00 0 USACE Steep R Riprap 0.040 0.035 NC-P63 Low 100 OSF1 NC-P63 725 0.0100 2.0 2.0 12.0 2.50 0 None G Grass-lined 0.035 0.030 NC-P64 Steep 100 OSF2 NC-P64 370 0.1660 2.0 2.0 12.0 2.50 0 Robinson R Riprap 0.040 0.035 NC-P64 Mod 100 OSF2 NC-P64 805 0.0590 2.0 2.0 12.0 2.50 0 USACE Steep R Riprap 0.040 0.035 NC-P64 Low 100 OSF2 NC-P64 1993 0.0100 2.0 2.0 12.0 3.00 0 None G Grass-lined 0.035 0.030 NC-P65 Steepl 100 OSF2 NC-P65 68 0.1360 2.0 2.0 10.0 2.00 0 USACE Steep R Riprap 0.040 0.035 NC-P65 Steep2 100 OSF2 NC-P65 750 0.0860 2.0 2.0 10.0 2.00 0 USACE Steep R Riprap 0.040 0.035 NC-P65 Mod 100 OSF2 NC-P65 200 0.0360 2.0 2.0 10.0 2.00 0 USACE Steep R Riprap 0.040 0.035 NC-P65 Low 100 OSF2 NC-P65 590 0.0100 2.0 2.0 10.0 2.50 0 None G Grass-lined 0.035 0.030 NC-P66a Steep 100 OSF3 NC-P66a 200 0.0620 2.0 2.0 8.0 2.00 0 USACE Steep R Riprap 0.040 0.035 NC-P66a Mod 100 OSF3 NC-P66a 320 0.0310 2.0 2.0 8.0 2.00 0 USACE Steep R Riprap 0.040 0.035 NC-P66a Low 100 OSF3 NC-P66a 530 0.0081 2.0 2.0 8.0 2.00 0 None G Grass-lined 0.035 0.030 NC-P67 100 OSF3 NC-P67 425 0.0520 2.0 2.0 0.0 2.00 0 None G Grass-lined 0.035 0.030 NC-P68 Steep 100 OSF3 NC-P68 130 0.0900 2.0 2.0 0.0 2.00 0 USACE Steep R Riprap 0.040 0.035 NC-P68 Mod 100 OSF3 NC-P68 230 0.0450 2.0 2.0 0.0 2.00 0 None G Grass-lined 0.035 0.030 NC-P69 Steep 100 OSF3 NC-P69 190 0.1170 2.0 2.0 8.0 2.00 0 USACE Steep R Riprap 0.040 0.035 NC-P69 Mod 100 OSF3 NC-P69 315 0.0690 2.0 2.0 8.0 2.00 0 USACE Steep R Riprap 0.040 0.035 NC-P69 Low 100 OSF3 NC-P69 305 0.0170 2.0 2.0 8.0 2.00 0 None G Grass-lined 0.035 0.030 NC-P661b Steep 100 OSF3 NC-P66b 220 0.0810 2.0 2.0 8.0 2.00 0 USACE Steep R Riprap 0.040 0.035 NC-P661b Mod 100 OSF3 NC-P66b 90 0.0310 2.0 2.0 8.0 2.00 0 USACE Steep R Riprap 0.040 0.035 NC-P661b Low 100 OSF3 NC-P66b 340 0.0200 2.0 2.0 8.0 2.00 0 None G Grass-lined 0.035 0.030 NC-DV6 Mod 100 OFS1 NV-DV6 565 0.0440 2.0 2.0 0.0 4.00 0 Robinson R Riprap 0.040 0.035 NC-DV6 Low 100 OFS1 NV-DV6 540 0.0080 2.0 2.0 0.0 5.00 0 None G Grass-lined 0.035 0.030 Page 1 of 2 SRK Consulting hnps://srk.shampdnt.coMsiW.INAUSPR000576/InWe .V0300_Hyd dogy/_SSP hyd dogy/020_Pnge data(w kingYHydraulic fflwinHBH Worksheel OSF Pen,June 2024.As, 6/25/2024 Table A-4 Channel Hydraulic Calculations Albemarle Kings Mountain PFS Date: 6/25/2024 Archdale Channel Design By:GKH PROJ NO.:USPR000576 Chkd: rvd: Hydraulic Calculations Channel Evaluations a cu ate y rau is Maximum Maximum Wave Runup Normal Flow Width Nominal Jump Depth/ Hydraulic Peak Flow Velocity in Normal Flow at Channel Depth Shear Top Width Top Width at Median Rlprap Size Impact Block Jump/Impact from HMS Channel Depth Froud Bends Stress (')Available Freeboard of Channel of Flow Depth (2)Channel Is Dsa Width Block Length Reach Designation (cfs) (ft/sec) (ft) Number (ft) (lbs/sq ft) (ft) (ft) (ft) (ft) Stable? (In) (ft) (ft) NC-P62 Steep 49.40 8.3 0.7 1.97 0.00 3.7 1.3 16.0 10.8 9.4 See Calc 10 NC-P62 Mod 49.40 6.9 0.8 1.53 0.00 2.5 1.2 16.0 11.3 9.6 See Calc 8 NC-P62 Low 49.40 4.1 1.0 0.83 0.00 0.6 1.0 20.0 15.8 13.9 Stable NC-P63 Steep 103.56 9.6 0.9 2.04 0.00 4.5 1.1 20.0 15.4 13.7 See Calc 10 NC-P63 Mod 103.56 8.7 0.9 1.76 0.00 3.6 1.1 20.0 15.8 13.9 See Calc 12 NC-P63 Low 103.56 5.3 1.5 0.89 0.00 0.9 1.04 22.0 17.9 14.9 Stable NC-P64 Steep 150.26 13.7 0.9 2.87 0.00 9.0 1.6 22.0 15.5 13.7 See Calc 16 NC-P64 Mod 150.26 9.7 1.2 1.79 0.00 4.3 1.3 22.0 16.7 14.4 See Calc 14 NC-P64 Low 150.26 5.9 1.8 0.91 0.00 1.1 1.2 24.0 19.2 15.6 Stable NC-P65 Steepl 59.07 9.7 0.6 2.45 0.00 5.0 1.4 18.0 12.4 11.2 See Calc 14 NC-P65 Steep2 59.07 8.4 0.7 1.99 0.00 3.6 1.3 18.0 12.7 11.4 See Calc 10 NC-P65 Mod 59.07 6.3 0.9 1.33 0.00 2.0 1.1 18.0 13.5 11.7 See Calc 6 NC-P65 Low 59.07 4.5 1.2 0.85 0.00 0.7 1.3 20.0 14.7 12.3 Stable NC-P66a Steep 21.34 5.6 0.5 1.59 0.00 1.8 1.5 16.0 9.9 8.9 See Calc 6 NC-P66a Mod 21.34 4.5 0.6 1.16 0.00 1.1 1.4 16.0 10.3 9.1 See Calc 6 NC-P66a Low 21.34 3.2 0.8 0.72 0.00 0.4 1.2 16.0 11.1 9.6 Stable NC-P67 7.86 5.8 0.9 1.69 0.00 2.8 1.1 8.0 3.5 1.7 Stable NC-P68 Steep 5.21 5.7 0.7 1.84 0.00 4.0 1.3 8.0 2.8 1.4 See Calc 9 NC-P68 Mod 5.21 5.0 0.8 1.53 0.00 2.2 1.2 8.0 3.1 1.5 Stable NC-P69 Steep 29.42 7.7 0.5 2.18 0.00 3.4 1.5 16.0 9.9 8.9 See Calc 9 NC-P69 Mod 29.42 6.5 0.5 1.72 0.00 2.3 1.5 16.0 10.2 9.1 See Calc 8 NC-P69 Low 29.42 4.5 0.8 1.04 0.00 0.8 1.2 16.0 11.0 9.5 Stable NC-P66b Steep 45.42 7.9 0.7 1.92 0.00 3.4 1.3 16.0 10.7 9.3 See Calc 10 NC-P66b Mod 45.42 5.8 0.9 1.23 0.00 1.7 1.1 16.0 11.5 9.8 See Calc 6 NC-P66b Low 45.42 5.5 0.9 1.16 0.00 1.2 1.1 16.0 11.7 9.9 Stable NC-DV6 Mod 140.50 10.0 2.8 1.61 0.00 7.7 1.2 16.0 11.2 5.6 See Calc 12 NC-DV6 Low 140.50 5.9 3.7 0.84 0.00 1.8 1.3 20.0 14.6 7.3 Stable Page 2 of 2 SRK Consulting hnps://srk.shampdnlcoMsiW.INAUSPR000576/i.We .V0300_Hyd dogy/_SSP hydrdogy/020_Prge Gala(-khgyHydrauli.M.inHBH Workshe OSF P.H.June 2024.A- 6/25/2024 Table A-5a Robinson Method Riprap Size Calculation Albemarle Kings Mountain PFS Date:1 6/25/24 Archdale Channel Design By: GKH PROJECT NO.: USPR000576 Chkd: Apprvd: Robinson Design of Rock Chutes Riprap Calculations for Steep Riprap(Bed Slopes>2%but<40%) Calculated Particle Size Calculated Nominal Design Flow Unit Width D50 Riprap Size Riprap Flow Q Concentration Flow q (2) Factor of D50 Size D50 Reach Designation (cros) Factor (cros/m) (mm) Safety (in) (in) NC-P63 Steep 2.932 1.25 0.877 198 1.20 9.35 10 NC-P64 Steep 4.254 1.25 1.269 324 1.20 15.30 16 NC-DV6 Mod 3.978 1.25 2.925 224 1.20 10.58 12 Design of Rock Chutes(ASAE Paper No.982136 7/98) Determine unit flow at incipient motion for rock particle size Unit flow rate is Q/median width,adjusted by a flow concentration factor of 1.25 (USAGE steep riprap method recommends a factor of 1.25) (2)Bed Slope<10%: q =9.76x10-7D501.89S-1.50 10%<=Bed Slope—40%: q=8.07x10-6D501'89S-0.58 1.2 Factor of Safety over incipient motion Page 1 of 1 SRK Consulting https://srk.sharepoint.com/sites/NAUSPR000576/Internal/0300_Hydrology/_SSP hydrology/020_Project data(working)/Hydraulics/BasinH&H Worksheet OSF Perim JUne@.ftI2024 Table A-5c U.S. Corps of Engineers (Steep) Method Riprap Size Calculation Albemarle Kings Mountain PFS Date: 6/25/24 Archdale Channel Design By: GKH PROJECT NO.: USPR000576 Chkd: Apprvd: USACE Method for flow in Channel Section Only Riprap Calculations for Steep Riprap (Bed Slopes>2%but<20%) Normal Calculated, Nominal Design Flow Flow Depth Flow Unit Flow Particle Riprap Riprap Reach Designation Q in Channel d Concentration q0) Size D30 Size D50 Size D50 (cfs) (ft) Factor (cfs/ft) (ft) (in) (in) NC-P62 Steep 49.4 0.69 1.25 6.58 0.64 9.9 10 NC-P62 Mod 49.4 0.81 1.25 6.41 0.46 7.2 8 NC-P63 Mod 103.6 0.94 1.25 9.33 0.67 10.4 12 NC-P64 Mod 150.3 1.18 1.25 13.09 0.82 12.8 14 NC-P65 Steep1 59.1 0.59 1.25 6.60 0.83 12.9 14 NC-P65 Steep2 59.1 0.68 1.25 6.50 0.63 9.9 10 NC-P65 Mod 59.1 0.87 1.25 6.29 0.38 6.0 6 NC-P66a Steep 21.3 0.47 1.25 2.99 0.32 4.9 6 NC-P66a Mod 21.3 0.57 1.25 2.92 0.21 3.3 6 NC-P68 Steep 5.2 0.71 1.25 4.59 0.52 8.1 9 NC-P69 Steep 29.4 0.47 1.25 4.12 0.56 8.7 9 NC-P69 Mod 29.4 0.55 1.25 4.05 0.41 6.4 8 NC-P66b Steep 45.4 0.67 1.25 6.08 0.59 9.2 10 NC-P66b Mod 45.4 0.88 1.25 5.81 0.33 5.2 6 USACE Paper EM 1110-2-1601,6/30/94 1.95So.55sg2/3 Where: D30=Rock size 30%passing,S=bed slope, D30 1 gee /3 q=unit flow,gee=gravity Inputs below as determined in EM 1110-2-1601,6/30/94 Unit flow rate is Q/median width,adjusted by a flow concentration factor of 1.25 (USAGE steep riprap method recommends a flow concentration factor of 1.25) Riprap D50 determined as recommended in EM 1110-2-1601,6/30/94 (D85 1/3 Where: Dx=rock size X%passing, Dso=D3a Dis 2.2 Cg: Gradation Coefficient(45015) �{�Page 1 ofII}2 https://srk.sharepoint.com/sites/NAUSPR000576/Internal/0300_Hydrology/_SSP�proQogS/t}20_%ject data(working)/Hydraulics/BasinH&H Worksheet OSF Perim June 2024.xism 6/25/2024 SRK Consulting(U.S.), Inc. Erosion and Sediment Control Plan Template—Kings Mountain Appendices Appendix El -C: Sediment Pond Designs MH/DH April 2024 Design Criteria,NDEQ Erosion Control Design Manual Practice Standard 6.61-Sediment Basin Design Criteria Summary: NOTE:Input data are blue text Primary Spillway: Riser/Barrel Pipe Maximum Drainage Area: 100 ac Minimum Sediment Storage Volume: 1800 ft3/ac of disturbed area Minimum Surface Area: 435 ft2/cfs of Q10 peak inflow Minimum L/W Ratio: 2 :1 Maximum L/W Ratio: 6 :1 Minimum Depth: 2 ft Dewatering Mechanism: Skimmer(s)attached at bottom of riser pipe or flashboard riser Minimum Dewatering Time: 48 hrs Baffles Required: 3 baffles (*Note:Basins less than 20 feet in length may use 2 baffles.) 0SF-1 Sediment Basin 62 Contributing Watershed 9.31 acres Check 10_YR Peak flow to Sediment Pond 34.00 cfs 100_YR Peak Channel Design Flow 65.00 cfs Design Pond Capacity to Spillway: 16,758 ft3 0.38 ac-ft Surface Area to Spillway: 14,790 sq ft 0.340 acres Top Dimensions Pond Top LengthEj ft Pond Top Widthft Pond Depth to Crestft Pond Depth to Spillwayft 2.00 ft spillway depth Pond Side SlopesH:1 V Depth at spillway 2.00 Check L/W Ratio 3.3 Check Pond Length at Spillway 240 Pond Width at Spillway 65 Pond Top Area at Spillway 15.600 x 1000 ft2 Pond Top Area at Spillway 0.358 acres Check 105% of Req'd Pond Bottom Length 230 ft Pond Bottom Width 55 ft Time to Drain.38 ac-ft pond with 3 in Skimmer Float Pond Bottom Area 0.29 acres with 3 in orifice Pond Volume at Spillway 0.65 ac-ft Check 169% of Req'd 7 2.5 0.2 0.291666667 Rymar Marlee Float Size 3 in 0.1 0.267253542 Rymar Marlee Orifice Size 3 in 2.0 w x 0.1 Initial Depth in Pond 2.0 ft a 3 Dewatered when Depth<= 0.1 ft o 1.5 0.1 0 Peak Outflow 0.146 cfs 0.1 0 66 gpm t 1.0 0.1 v Time to Dewater 57.0 hrs Check 119% of Req'd o 0.0 E 0.5 0.0 PMP Spillway Width 20 ft 0.0 0.0 PMP Spillway Side Slopes 2.5 H:1 V o 10 20 30 40 50 60 70 80 Weir Coefficient 3.09 Elapsed Time(hours) Peak Head in Spillway 1.00 ft 100_YR Peak Inflow to Pond 65.0 -Depth in Pond -Skimmer Outflow Peak Outflow from Spillway 68.0 cfs Check 105% of 100_YR Freeboard in Spillway 1.00 ft Design Criteria,NDEQ Erosion Control Design Manual Practice Standard 6.61-Sediment Basin Design Criteria Summary: NOTE:Input data are blue text Primary Spillway: Riser/Barrel Pipe Maximum Drainage Area: 100 ac Minimum Sediment Storage Volume: 1800 ft3/ac of disturbed area Minimum Surface Area: 435 ft2/cfs of Q10 peak inflow Minimum L/W Ratio: 2 :1 Maximum L/W Ratio: 6 :1 Minimum Depth: 2 ft Dewatering Mechanism: Skimmer(s)attached at bottom of riser pipe or flashboard riser Minimum Dewatering Time: 48 hrs Baffles Required: 3 baffles (*Note:Basins less than 20 feet in length may use 2 baffles.) 0SF-1 Sediment Basin 63 Contributing Watershed 30.58 acres Check 10_YR Peak flow to Sediment Pond 52.00 cfs 100_YR Peak Channel Design Flow 113.00 cfs Design Pond Capacity to Spillway: 55,044 ft3 1.26 ac-ft Surface Area to Spillway: 22,620 sq ft 0.519 acres Top Dimensions Pond Top Length 300 ft Pond Top Width 110.0 ft Pond Depth to Crest 6.00 ft Pond Depth to Spillway 4.00 ft 2.00 ft spillway depth Pond Side Slopes 2.5 H:1 V Depth at spillway 4.00 Check L/W Ratio 2.7 Check Pond Length at Spillway 290 Pond Width at Spillway 100 Pond Top Area at Spillway 29.000 x 1000 ft2 Pond Top Area at Spillway 0.666 acres Check 128% of Req'd _ Pond Bottom Length 270 ft Pond Bottom Width 80 ft Time to Drain 1.26 ac-ft pond with 6 in Skimmer Float Pond Bottom Area 0.50 acres with 5 in orifice Pond Volume at Spillway 2.32 ac-ft Check 184% of Req'd 7 5 0.6 0.291666667 Rymar Marlee Float Size 6 in 4 0.267253542 Rymar Marlee Orifice Size 5 in 4 o.s Initial Depth in Pond 4.0 ft a 3 0.4 3 Dewatered when Depth<= 0.1 ft `0 3 Peak Outflow 0.523 cfs ` 2 0.3 0 235 9pm Time to Dewater 57.5 hrs Check 120% of Req'd o 2 o.z £ 1 0.1 1 PMP Spillway Width 35 ft 0 0.0 il PMP Spillway Side Slopes 2.5 H:1 V 0 10 20 30 40 so 60 70 80 Weir Coefficient 3.09 Elapsed Time(hours) Peak Head in Spillway 1.00 ft 100_YR Peak Inflow to Pond 113.0 -Depth in Pond -Skimmer Outflow Peak Outflow from Spillway 114.3 cfs Check 101% of 100_YR Freeboard in Spillway 1.00 ft Design Criteria,NDEQ Erosion Control Design Manual Practice Standard 6.61-Sediment Basin Design Criteria Summary: NOTE:Input data are blue text Primary Spillway: Riser/Barrel Pipe Maximum Drainage Area: 100 ac Minimum Sediment Storage Volume: 1800 ft3/ac of disturbed area Minimum Surface Area: 435 ft2/cfs of Q10 peak inflow Minimum L/W Ratio: 2 :1 Maximum L/W Ratio: 6 :1 Minimum Depth: 2 ft Dewatering Mechanism: Skimmer(s)attached at bottom of riser pipe or flashboard riser Minimum Dewatering Time: 48 hrs Baffles Required: 3 baffles (*Note:Basins less than 20 feet in length may use 2 baffles.) 0SF-1 Sediment Basin 64 Contributing Watershed 13.30 acres Check 10_YR Peak flow to Sediment Pond 47.00 cfs 100_YR Peak Channel Design Flow 96.00 cfs Design Pond Capacity to Spillway: 23,940 ft3 0.55 ac-ft Surface Area to Spillway: 20,445 sq ft 0.469 acres sio ns Pond Top Le�gth 220 ft Pond Top Width 110.0 ft Pond Depth to Crest 4.00 ft Pond Depth to Spillway 2.00 ft 2.00 ft spillway depth Pond Side Slopes 2.5 H:1 V Depth at spillway 2.00 Check L/W Ratio 2.0 Check Pond Length at Spillway 210 Pond Width at Spillway 100 Pond Top Area at Spillway 21.000 x 1000 ft2 Pond Top Area at Spillway 0.482 acres Check 103% of Req'd Pond Bottom Length 200 ft Time to Drain.55 ac-ft Pond with 6 in Skimmer Float with 3.5 in orifice Pond Bottom Width 90 ft Pond Bottom Area 0.41 acres 18000 Time to Drain .55 ac-ft pond with 6 in Skimmer Float Pond Volume at Spillway 0.90 ac-ft Check 163%of Req'd with 3.5 in orifice 7 0.291666667 Rymar Marlee Float SizeEN in 3 0.3 0.267253542 Rymar Marlee Orifice Sizein Initial Depth in Pondft2 0.2 Dewatered when Depth- ft 3 0 2 Peak Outflow 0.2211 cfs 2 0.2 o 9Pm Time to Dewater 53.0 hrs Check 110% of Req'd a i 0.1 v E 0i o.iy PMP Spillway Width 30 ft PMP Spillway Side Slopes 2.5 H:1 V 0 0.0 Weir Coefficient 3.09 0 10 20 30 40 50 60 70 80 Peak Head in Spillway 1.00 ft Elapsed Time(hours) 100_YR Peak Inflow to Pond 96.0 Peak Outflow from Spillway 98.9 cfs Check 103%of 100_Y -Depth in Pond -skimmer outflow Freeboard in Spillway 1.00 ft