mm ONFIDENTIAL A TTORNE WORK PR 0D UC HYDROLOGIC EVALUATION OF JULY 17, 2010 FLOODING IN THE HARLESS CREEK WATERSHED PIKE COUNTY, KENTUCKY Prepared for Ned Pillersdorf, Esq. Pillersdorf, DeRossett 8: Lane 124 West Court Street Prestonsburg, VA 41653 Prepared by John]. Eichenberger, P.E., CIH Senior Consultant Faulkner 8: Inc. 101 South Jefferson Street, 2??1 Floor Roanoke, VA 24011 August 24, 2011 \mu NN Con?dential Attorney Work Product TA 3 LE OF CONTENTS EXECUTIVE SUMMA SI 12 TE INS OF DATA REL IEDUP 1 BASE PECTIONS No 1.3 momemm 2 1-3.1 Radar Data 8 IFLOWS 8 .3 NOAA 8 1.4 Olnt Estlmates sgii?ligig?g?m SOIL GROUP DATA 11.6 SURVEYW VE NUMBERS 9 .7 FLOOD 9 RD CLAS 2,0 METHODOLOGY SIFICATION 9 2-1 11 2?2 11:11 2- 3 RA INF EVALUATION 2.4 DEL 11 2 5 INEATION OF MINED AREAS 12 - PEAK STORMWATER RUNOFF MODELING 12 2-5-1 Sub-Watershed Areas 13 2.5.2 SCS Runoff Curve Numbers 13 2.5.3 Time of Concentration and Lag 14 2.5.4 Routing Reaches 15 2'5 FLOOD RECURREN CE INTERVAL EVALUATION 15 2.7 SEDIMENTATION POND PERFORMANCE EVALUATION 15 2.8 HARLESS CREEK HYDRAULIC MODELING 16 3.0 RESULTS AND OPINIONS 17 3.1 PEAK STORMWATER RUNOF EVALUATION 17 3.2 FLOOD FREQUENCY EVALUATION 19 3.3 SEDIMENTATION POND PERFORMANCE EVALUATION 20 3.4 HARLESS CREEK HYDRAULIC MODELING 21 4.0 PROFESSIONAL QUALIFICATIONS 2 5.0 REFERENCES 2 List 01' Figures Figure 1 Harless Creek Watershed Site Loeation Map . Figure 2 Permitted Surface Mining Operations, Harless Creek Watershed, Pike County, Kentuc' Figure 3 Rainfall Distribution for July 17, 2010 Storm Event, Harless Creek Watershed, P1 County, Kentucky Figure 4A Kentucky Figure 4B Current Pre-Mning Watershed Drainage Areas, Harless Creek Watershed, Pike Cou Mining Watershed Drainage Areas, Harless Creek Watershed, Pike C011 Kentucky an In FAULKNER Gr. Con?dential Attorney Work Product TABLE OF CONTENTS (continued) Tabl . ble 1 Permitted Surface Mini 0 . a 2 Sub?Watershed A 11g Peratlons, Harless Creek Watershed, Pike County, Kentucky Conditicm 1 reas Characteristics for the Pre?Mining and Current?Mirang Land Use Table 3 Peak ar ess Creek Watershed, P1ke County, Kentucky Based 2:01?- Floivs and Percent Change in Peak Runoff for Seven Sub?Watershed Areas Mo (1 e1 St and Current-mining Land Use Conditions For the )uly ?17, 2010 Orm'and the 2, 5, 10, 25, 50 and 100 Recurrence Interval Storms. Harless Creek Table 4 Chatershed, Pike County, Kentucky. 1n Peak Flow and Flooding Risk from Pre-Mining and Current?Mining 110115 based on a based on a 1 (1000/0), 2 5 (250/0) ,10 (100/0), 25 50 0) and 100. Year Recurrence Interval SCS 24-Hour Storm Event. Harless Creek atershed, Plke County, Kentucky. L15 01" Appendices ?ppendix 1 January, 2011 Hairless Creek Survey Data ppendrx 2 Precipitation Data and Hyetograph, IFLO Appendix 3 Photographs Appendix 4 Harless Creek Cross-Sections for the July Ws Station East Ridge High School, Statio ID 17, 2010 Model Storm Based on Pre?Mini and Current Mining Land Use Conditions Appendix 5 Professional Quali?cations Con?dential Attorney Work Product XECUTIVE SUMWY In Au gm? 2010, Faulk net I lynn, Inc. (142) was retained by Fillersdorf, at Lane minin the Harless Creek ?Watershed on peak stormwatcr to valuate the effect of surface On july 17, 2010, Harless Creek experienced a catastrophic run 0 and ?ooding of Harless Creek. tha seVereI - . 3 amaged or destroyed a signi?cant number of homes and outbuildings within the Hat-less Cr eek atershed. The location of the Harless Creek \?C?atershed is shown on Figure 1. The mining operations located within the Hat-less Creek \V?atershed are listed in Table 1 and Show . lgure 2. F2 prepared representative hydrologic and hydraulic models of the Harless Creek Watershed for the penod prior to surface mining (pro?mining land use condition) and at the time . the July 17, 2010 ?ooding (current mining land use condition). 'l'hesc models were used to evalu at - - . a . how the surface operations of Cambrian (.oal Corporation and Kentuc ky Coal, LLC affected the balance and flooding within the Hat-less Creek Watershed. TABLE 1 Permitted Surface Mining Operations Harless Creek Watershed Pike County, Kentucky 898?0660 AEP Kentucky Coal, LLC Permit released 893?0649 AEP Kentucky Coal, LLC Phase I release A 898-0618 Cambrian Coal Corporation Active, currently being mined A 898?061 9 Cambrian Coal Corporation Active, currently being mined 898?0819 Cambrian Coal Corporation Active, currently being mined F2 used the HEC-HMS modeling software models of pre-mining and current mining land surface conditi to surface mining related activities such as topso conditions due and construction of valley ?lls and grading, runoff ?ows is attributed to the surface mining operational methods used Corporation and AEP Kentucky Coal, LLC. The Harless Cre hear (if) an? (HEC-HMS) to construct representative hydrologic ons within the Harless Creek Watershedm The current mining hydrologic models incorporated the changes in land sur il removal, mass excavation and face haul roads. The difference in the peak stormwater by Cambrian Co ek Hydrologic Model was used 08/24/ FAULKNER Con?dential Attorney Work Product compute the peak Stormwater . . runoff for the prc-mltung and current mining land uses for the conditions listed below. The m? :mg 2010 model storm) as well as th 0! at ?55 (Steak Watershed 011W 17, (Chane standard 24?hour 1 year (100% annual probability 2 Year (500/0), 5 Far 10 Year 25 year 50 Year and 100 Year average recurrence interval storms (standard recurrence interval storms). This hyC-h'degic evaluation assessed the probable Cumulative hydrologic impacts of all mining actlv1t1es within the Creek W?atershed and addressed elements of the cumulative 11 ch- Olog?t unpact assessment (CI-ILA) process, as set forth in 30 CFR 780.21(ffect of the permitted surface coal mining operations on peak stormwater runoff for re . . . presentanve sub-watershed areas was quann?ed. The determination of the impact urface coal mining operational methods on ?ooding is required as part of a probable hydrologic consequences determination (PHCD) as set forth in 30 CFR and 405 KAR 8:30.323. The peak stormwater runoff for the standard recurrence interval storms was evaluated to determine how the Cambrian Coal Corporation and AEP Kentucky Coal, LLC surface mining operations affected the frequency and intensity of ?ooding in the Harless Creek Watershed. The Harless Creek hydrologic model was used to determine if the sedimentation ponds located in Permit Area No. 898?0619 were adequately designed, constructed and maintained to attenuate peak runoff ?ows generated during the July 17, 2010 model storm and the standard 10?year recurrence interval storm. 3 constructed using the HEC-RAS modeling software (HEC- The Hadess Creek hydraulic model wa EP Kentucky Coal, LLC RAS) and used to determine how the Cambrian Coal Corporation and A affected the water depths and ?ow velocities within Harless Creek and surface mining operations The Harless Creek hydraulic model results and guidance published by 8 ining overbank areas. adjo rtrnent of Interior Bureau of Reclamation (U Bureau of Reclamation), were the United States Depa 03/24/11 PDL.612.567 FAULKNER G: Con?dential Attorney Work Product used to det . ermine how the Cambrian Coal Corporation and AEP Kentucky Coal, LLC surface minim Operations affected ?ood flow hazards during the July 17, 2010 The 11 . Owrng Conclusions have been reached based on this hydrologic study of the Harless Creek Watershed: l. - . . The change 11'] land cover conditions resulting from the Cambrian Coal Corporation and AEP Kentucky Coal, LLC surface mining operations and failure to properly reclaim mined areas resulted in a 44% increase in peak stormwater runoff during the July 17, 2010 model storm, The peak stormwater runoff increased from 3,020 cubic feet per second (cfs) to 4,360 for the current mining condition. The peak runoff generated within seven representative sub~Watershed areas was signi?cantly increased during the current mining Condition for the July 17, 2010 model storm and the standard recurrence interval storms. These increased peak ?ows are the direct result of the Cambrian Coal Corporation and AEP Kentucky Coal, LLC surface mining operations and the failure to properly reclaim surface mined areas. The increased peak stormwater runoff ?ows exacerbated ?ooding and Signi?cantly increased the destructive force of the ?ood water during the July 17, 2010 ?ood. The AEP Kentucky Coal, LLC and Cambrian Coal Corporation surface mining activities and the failure to properly reclaim mined areas increased the intensity and frequency of ?ooding within the Harless Creek Watershed. The speci?c increase for each ?ood recurrence interval storm is as follows: The ?ooding risk for the 2 year storm (50% annual probability (chance)) increased by . more than 200% during the current mining period. Areas within the pics?mining 2 year ?oodplain are now at risk of ?ooding more than once a year. The ?ooding risk for the 5 year storm (20% annual probability (chance)) increased 450% during the current mining period. Areas within the pre-mining 5 year ?oodplain are now at risk of ?ooding every 1.1 years (91% annual probability (chance)). The ?ooding risk for the 10 year storm (10% annual probability (chance)) increased 450% during the current mining period. Areas within the pre-mining 10 year 08/24/1 PDL.612.567 Con?dential Attorney Work Product ?oodplain are now at ri - (Chance). 5 of ?ooding every 2.2 years annual probability . The ?oodin th . . 4700/0 du?n th or 25 year storm (40/0 annual probability (chance)) increased - - - . . ?OOdplain are urren-t mining period. Areas Within the pre?rnining 25 year now (Cl/lance?. a risk of ?ooding every 5.4 years (19% annual probability 0 Th . 4 OOd-mg 115k for the 50 year storm annual probability (chance)) increased 70W . . . 0 dumg the current mining period. Areas Within the pre-mining 50 year 0 - . 0 plain are now at risk of ?ooding every 11.2 years annual probability (Chance)). '1 . . he ?ooding risk for the 100 year storm annual probability (chance)) increased 0 . . . 460 /0 du?ng the current mining period. Areas within the pro-mining 100 year ?oodplain are now at risk of ?ooding every 21.7 years annual probability (chance)). The likelihood of severe ?oods causing property damage and the potential loss of life has increased signi?cantly as a direct result of the failure of Cambrian Coal Corporation and AEP Kentucky Coal, LLC to properly reclaim surface mined areas. Catastrophic ?ooding similar to the magnitude experienced on July 17, 2010 can now be expected to occur repeatedly during the typical lifespan a resident living within the Harless Creek Watershed. 3. The representative sedimentation ponds located on Cambrian Coal Corporation Permit Area 898?0619 were not properly designed, constructed and maintained to reduce peak stormwater ?ows during the July 17, 2010 model storm and the 10-year average 21 storm. These data con?rm that the sedimentation ponds located on recurrence interv Cambrian Coal Corporation Permit Area 898?0619 were inadequate to signi?cantly reduce peak stormwater ?ows and did not protect against ?ooding during the luly 17, 2010 storm. The change in land cover conditions associated with the Cambrian Coal Corporation and erly reclaim mine AEP Kentucky Coal, LLC surface mining operations and failure to prop areas signi?cantly increased the water depth and ?ow velocities widiin Harless Creek durin 08/24/ $1311.612567 Confidential Attorney Work Product the July 17, 2010 model stonn. The average ?ow depth increased approximately 1.25 feet (ft) while the flow velocities in the left and right overbank areas increased approximately 54 percent and 31%, respectively. The increased water depths and velocities expanded thfi high danger zone for the left and right over-bank areas by 286% and 156%, respectively. The high danger zones are areas where lives were in jeopardy due the combined flow depth and conditions.(15) The increased ?ow depth and velocities exacerbated flooding Within the Harless Creek Watershed, placed lives in jeopardy and signi?candY increased the destructive energy of the July 17, 2010 ?ood waters. r81 1.0 1.1 1.2 PDL.612.567 Con?dential Attorney Work Product SUMMAR OF DATA RELIED UPON The foll ?3an data as relied upon to develop the conclusions stated in this report SITE INSPEC TIONS F2 ins ecte inspe (31:10:13 3::Zsejrsek Watershed ?on August 11 2010 and January 19, 2011. The Shimp, RE.) and area reSid Mr. John P.E., Mr. jack Spadaro, Mr. jus?? features, Vegeta?Ve COV l?nt Mr- Freddie Coleman. The local topography and geographic Watershed were dire ?er? :nd use Conditions and mining practices Within the Harless Creek inspection F2 0 served during these inspections. During the August 11, 2010 completed a ?yover of the permitted surface mining operations within the Harless Cr eek Watershed. F2 also attempted to drive up Harless Creek Road, but could not sed by a 2?year recurrence interval storm. F2 pass due to the ?ooding of Harless Creek can and inspected the full length of Harless Creek returned to Harless Creek on January 19, 2011 from Route 460 to its con?uence with Powell Hollow. BASE AND AERIAL PHO T0 GRAPHY DA TA Two base site maps of the Harless Creek Watershed were prepared using numerous publicly available data sources. The pre?mining base map represented the Harless Creek Watershed prior to surface mining (pm?mining land use co Harless Creek Watershed at the time of the ndition) and the current mining map july 17, 2010 ?ood (current Kentucky State Plane maps for the represented the mining land use condition). The Base Maps were geo-referenced to data and mine reclamation plan Coordinates to align with ?eld survey Base Map was manipulated using either All data included in th software and data obtained from th ur Data: Elevation contours for the tes Geological Survey (USGS) (DTM) is a 30?meter gri permitted surface mines. ARCview G18 or AutoCA 1. Pre?Mining Elevation Conto derived from the United Sta This digital terrain model the USGS quadrangle record best available elevation data th following sources: pre?mining Base Map Wet national elevation dataset 1 based on photographs fro model is considered to be the mode 5 maps for th subject area. This the USGS will provide to the public. Con?dential Attorney Work Product 2 . - urrent Nlmin - . levatlon Contour Data: Elevation data and contours for the current minin conditions were derived from Intennap 5 meter resolution digital elev ti - - a on models. A bare earth digital terrain model (DTM) of the Harless Creek Watershed was obtained and 20 foot interval contours were created from the DTM. 3. EOgraphic Site Features: All roads, streams, USGS gauge stations and t0 ?7115/ Communities were gathered from multiple sources GeOgraphic Names: All geographic names were obtained from the USGS Geographic Names Information System This system was developed by the USGS and is the of?cial repository of domestic geographic names data for the Federal government. Stream and River Data: All stream and river data was obtained from the USGS through its National Hydrography Datasetfm) 4- Mme Reclamation Plan Maps: Mine Reclamation Plan (MRP) maps of all pennitted surface mining areas in the Harless Creek Watershed (Surface Nline Area Maps) were obtained from the Commonwealth of Kentucky, Department for Natural Resources, Division of Mine Permits?) The MRP maps are scanned and goo-referenced and made available for downloading via FTP. The most current I MRP for each permitted area was downloaded and overlaid on the current mining Base Map using ARCview GIS. Aerial Photography: A 1-meter aerial photograph taken on july 24, 2010 was obtained from the United States Department of Agriculture (USDA) National Agriculture Imagery Program This aerial imagery is compiled in the continental United States for the purpose of making digital photography available to governmental agencies and the public. This imagery dataset has been projected into Kentucky Single Zone, NAD 83, US Survey Feet, FIPS 1600. The aetia photography was then exported from ARCview GIS into as a big resolution TIFF image for use with both the pre?mining and current mining Ba Maps. 08/ 24 PDL.612.567 Con?dential Attorney Work Product 1.3 Rainfall data for the Harless Creek Watershed was compiled from the following sources: Radar Data; and . - I National Oceanic and Atmospheric Administration (NOAA) Point Precipitation Estimates. 1-3.1 Radar-Data Radar Data from the National Mosaic Q2 System was used to determine the depth of rainfall within the Harless Creek Watershed for the July 17, 2010 stormy?) The National Mosaic Q2 System collects data from a variety of sources including 128 radar sites. The Stage II Q2 (Radar Only) quantitative precipitation estimation (QPE) was used to quantify the depth of precipitation within the Harless Creek Watershed during the July 17, 2010 and August 11, 2010 storm events. 1.3.2 W5 Precipitation data for the former IFLOWS Station East Ridge High School (Station ID Latitude: 37? 20' 43.0008" Longitude: ?82? 19' which was located approximately 4.2 miles east of the Harless Creek Watershed, was used to develop the july 17, 2010 model sweat?) (Appendix 1) 1.3.3 NOAA Point Precipitation Estimates Precipitation frequency estimates for the Harless Creek Watershed were obtained from NOAA Atlas 14, Volume 2, Version 3 (N 0AA Atlas The NOAA Atlas 14 serves as the of?cial documentation of precipitation frequency estimates and associated information for the United States and contains precipitation frequency estimates for Kentucky. The 24? hour rainfall precipitation depths for the 2 year 5 year 10 year 25 year 50 year and 100 year average recurrence interval storms (standard recurrence interval storms) were used with the Harless Creek hydrologic model to determine ows for these standard recurrence interval storms. The recurrence interval is based peak fl 08/24/11 1.4 1.5 1.6 1.7 Con?dential Attorney Work Product on the probab?j - ty (chance) that the given event will be equaled or exceeded in any given YearChance that a lOO-year storm will occur in any given Yeat- SO IL YDROLOGIC SOIL GROUP DATA . . 0:8:6 hydrologicsoil groups (HSG) within the Harless Creek Watershed data prov1ded on the Natural Resources Conservation Service 3011 The survey provides detailed information on the makeup, and HSG classi?cation of the various soil types within the Harless Creek Wat ershed, These data were used to develop runoff curve numbers for land unaffected by surface mining. SCS RUNOFF CURVE NUMBERS he SCS I'ImOff curve numbers (curve numbers) for the presniining land use condition and unreclaimed surface mine areas were obtained from the NRCS Engineering Handbook and the SCS Manual.(9? 12) The curve numbers for the reclaimed surface mined areas were obtained from Wagner et all?) All curve numbers were developed based on these references, the HSG and direct inspection of the Harless Creek Watershed. SUR The hydraulic model of Harless Creek was developed using data collected during a ?eld survey completed by R.R. Crawford Engineering, Inc. in January, 2011. During the survey, twelve (12) cross?sections were surveyed along Harless Creek from immediately of the most residence up to the con?uence of Harless Creek with Oney Fork. All survey data was collected in Kentucky State Plane South, NAD1983 Coordinates. The copy of the survey coordinate points is included in Appendix 1. FLOOD HAZARD CLASSIFI CA TI 0N Guidance published by the U.S. Bureau of Reclamation (USBOR) was used to evaluate the July 17, 2010 model storm due to water depth (15) The Harless Creek Hydraulic Model was used to Creek Stud hazards created by the ?velocity conditions within Harless Creek overbank areas. calculate the water depths and ?ow velocities along the length of the Harles 08/24/1 PDL.612.567 a! Con?dential Attorney Work Product Area. ?l'hese water depth and flow Velocity ?ood danger level relations built on foundations to identify W11 elocitjes were compared to the depth hips for passenger vehicles. mobile homes and houu-?s ere high danger zones existed within the Harless (Creek ox'el'bank area during july 17, 2011 model storm. high danger zone is de?ned as a here hves are geopardy due 3 Combination of ?ow depth and velomty. 10 03:24:11 PDLMESE Con?dential Attorney Work Product 3. 0 RESULTS AND OPINIONS 3. I AK STORMWA TER UN OFF EVALUATION The . . LLC :1:1:Iga :oal Corporation and AEP Kentucky Coal, surface the fa?me to properly radium permitted mlne areas resulted in a 44% mcrease in peak stormwater runoff for the Harless Creek Watershed based on the July 17, 2010 model storm. The peak stormwater runoff for the PIC-mining condition was approximately 3,020 cubic feet per second (cfs) and increased to 4,360 during the current mining condition. This increase in peak stormwater runoff Exacerbated ?ooding during the July 17, 2010 storm event and signi?cantly increased the destructive energy of the ?ood waters. . . . he peak stormwater runoff for seven sub?watershed areas increased Signi?cantly from the pie?mining to the current mining land use conditions based on the july 17, 2010 model The seven sub?watershed areas included Permit Nos. 898-0660 8: 898?0649), Slate Right Fork Harless Creek storm and standard recurrence interval storms. Burnt Tree Hollow (Sub?watershed Area 15, Dump Hollow (Sub?watershed Area 10, Permit No. 898?0649), ermit No. 898?0649), 88?39 contributing area ?watershed Area 11 Permit (Sub?watershed Area 7, (Sub?watershed contributing area (Sub ?Watershed Area 8, Permit Nos. 898?0618 8: 898-0619), 05. 898?0618 8: 898?0619 The ?ows Area 13, Permit No. 898?0919 No. 898?0919), Oney Fork (Sub Frankie Fork (Sub?watershed Area 5, Permit and 3. These increased peak ?watershed areas are summarized in Table event and will exacerbated ?ooding during the july 17, 2010 storm oding in the Harless Creek Watershed now and in th for the seven sub stormwater runoff flows result in more frequent and intense ?o future. EP Coal Kentucky, LLC failed to properly surface 0 the july 17, 2010 ?ood. The failure al and caused signi?ca Cambrian Coal Corporation and A the Harless Creek Watershed prior ce mined areas increased the runoff potenti This exacerbated ?ooding during the ]uly 17, 2 nergy and widespread darn areas Withi properly reclaim surfa peak stormwater runoff ?ows. higher storm event, signi?cantly increased the ?oods destructive 6 08/2 17 tantra-2,567 81 FLY DI a Con?dential Attorney Work Product The failur - . Properly reClaim surface mined areas is corroborated by Kentucky Division of Mine Enfo rcernent and Reclamation (DMR) records and the direct inspection of surface mining activities. 0 I . August 2010, the DMR Cited the Cambrian Coal Corporation Permit No. 898- 0619 (NOn?Compliance Number 53?2478) for failing to complete contemporaneous reck?natiO? work in six mine increments within the prescribed time period. The failure '50 pIOperly reclaim these areas exposed these high runoff areas to the )uly 17, 2010 storm. F2 inspected Permit No. 898?0619 in August, 2010 and observed Wldespread erosion damage. This con?rmed that the Cambrian Coal Corporation?s fallure to complete contemporaneous reclamation work increased the peak runoff ?ows from the surface mine areas which signi?cantly increased ?ooding during the July 17, 2010 storm event. arless Creek Watershed, F2 observed 0 During the August 2010 inspection of the large reclaimed surface mine areas with poorly vege These conditions were tated surfaces, signi?cant erosion present in both the damage and numerous landslides. mines (Table 1). a1 Corporation and AEP Kentucky Coal, LLC surface Cambrian Co con?rms that the Cambrian Coal Corporation and The widespread erosion damag AEP Kentucky Coal, LLC failed to properly runoff potential and significantly increased the reclaim these surface mine areas which increased th peak runoff flows during July 17, 2010 storm. for Cambrian Coal Corporation and AEP Kentucky Coal, Harless Creek Watershed, which the july 17 The surface Mg operations dversely affected the hydrologic balance of th I runoff and exacerbated ?ooding durin al Corporation have failed LLC have a increased cumulative peak stormwate t. AEP Kentucky Coal, LLC and Cambrian Co tect the hydrologic balance outside the pe peak storrnwa 2010 storm even take the adequate measures necessary to pro 405 KAR and which has increased the This increased risk will continue into areas as required by flows and the likelihood of destructive ?ooding. the surface mines are properly reclairne nan Coal Corporation and Kentucky d. Further surface disturbance wi future unless the I-Iarless Creek Watershed by the Camb -?-vuu Con?dential Attorney Work Product Th . . . . ?3 failure to properly reclaim surface mined areas is corroborated by Kentucky Diwslon of Mme Enforcement and Reclamation (DMR) records and the direct inspection of surface milling activities. In August 2010, the DMR cited the Cambrian Coal Corporation Permit No. 898- 0619 (N on-Compliance Number 53?2478) for failing to complete contemporaneous reclamation work in six mine increments within the prescribed time period. The failure to properly reclaim these areas exposed these high runoff areas to the july 17 2010 storm. F2 inspected Permit No. 898-0619 in August, 2010 and observed Widespread erosion damage. This con?rmai that the Cambrian Coal Corporation?s failure to complete contemporaneous reclamation work increased the peak runoff ?ows from the surface mine areas which signi?cantly increased ?ooding during the July 17, 2010 storm event. Harless Creek Watershed, F2 observed 0 During the August 2010 inspection of the (1 surfaces, signi?cant erosion large reclaimed surface mine areas with poorly vegetate These conditions were present in both the damage and numerous landslides. Cambrian Coal Corporation and AEP Kentucky Coal, LLC surface mines (T able 1) The widespread erosion damage con?rms that the Cambrian Coal Corporation an AEP Kentucky Coal, LLC failed to properly reclaim these surface mine areas whic increased the runoff potential and signi?cantly increased the peak runoff ?o during July 17, 201 0 storm. The surface mining operations for Cambrian Coal Corporation and AEP Kentucky LLC have adversely affected the hydrologic balance of the Harless Creek Watershed, increased cumulative peak stonnwater runoff and exacerbated ?ooding during the july 2010 storm event. AEP Kentucky Coal, LLC and Cambrian Coal Corporation have fail take the adequate measures necessary to protect the hydrologic balance outside the areas as required by 405 KAR and which has increased the peak storm ?ows and the likelihood of destructive ?ooding. This increased risk will continue in future unless the surface mines are properly reclaimed. Further surface disturbance the Harless Creek Watershed by the Cambrian Coal Corporation and AEP Kentuck 3.2 Con?dential Attorney Work Product LLC Surface mining Operations will adversely affect the cumulative hydrologic balance and further exacerbate these risks. FL 000 FREQUENCY VAL UA TION The freqUency and intensity of ?ooding within the Harless Creek Watershed has been operations of Cambrian Coal Corporation and AEP exacerbated due to the surface minin Kentucky Coal, LLC. The Speci?c increases in the peak flow and ?00d recurrence interval Storm for the standard recurrence interval storm are summarized below and in Table 4. These results con?rm that the Cambrian Coal Corporation and AEP Kentucky Coal, LLC surface mining operations have adversely changed the hydrologic conditions for signi?cant reclaim the surface mined Portions of the Harless Creek Watershed and failed to properly This has adversely affected the cumulative hydrologic balance for the Harless Creek areas. Watershed such that ?ooding will occur more frequently and with greater intensity. The ?ooding risk for the 2 year storm (50% annual probability (chance)) increased by more than 200% year ?oodplain are now at risk of ?ooding more than once a year. 0 The ?ooding risk for the 450% ?oodplain are now at risk of ?ooding every 1.1 years (91% annual (chance)). during the current mining period. Areas within the pre?mining 2 5 year storm (20% annual probability (chance)) increased during the current mining period. Areas within the pre-mining 5 year probability The ?ooding risk for the 10 year storm (10% annual probability (chance)) increased 0 450% during the current mining period. Areas within the pre?mining 10 year ?oodplain are now at risk of ?ooding every 2.2 years (45% annual probability (chance)). 0 The ?ooding risk for the 25 year storm annual probability (chance)) increased 470% ?oodplain are now at risk of ?ooding every 5.4 years (chance)). during the current mining period. Areas within the pre?mining 25 year (19% annual probability 19 1.612.567 08/24/11 3.3 FAULKNER S: Con?dential Attorney Work Product The ?OOding risk for the 50 year Storm annual probability (chance)) increased 470% during the current mining period. Areas within the pro-mining 50 year ?OOdPla?ln are now at risk of ?ooding every 11.2 years annual probability (ChanceJ). The flooding risk for the 100 year storm annual probability (chance)) increased 460% during the current mining period. Areas within the pre-rnining 100 year ?oodplain are now at risk of ?ooding every 21.7 years annual probability (chance)). The likelihood of severe ?oods causing property damage and the potential loss of life has increased signi?cantly as a direct result of the failure of Cambrian Coal Corporation and AEP Kentucky Coal, LLC to properly reclaim surface mined areas. Catastrophic ?ooding similar to the magnitude experienced on July 17, 2010 can now be expected to occur repeatedly during the typical lifespan of a resident living within the Harless Creek Watershed. SEDIMEN TA TION POND PERF ORAJAN CE VAL UA TI 0N Three sedimentation ponds, 88?32, 88?33 and 88?39, are located at the base of hollow ?lls on the Harless Creek side of Cambrian Coal Corporation Permit Area 898?0619. One representative sedimentation pond, 88-39, was evaluated to determine its capacity to reduce peak flows from the July 17, 2011 model storm and the 10?year average recurrence interval storm. 88?39 reduced the peak stormwater ?ows by only approximately 12%. Therefore, 38?39 did not protect against ?ooding during the July 17, 2010 storm and does not meet the basic requirements of 405 KAR 16:090 Section In July 2010, following the July 17, 2010 ?ood event, the Kentucky Division of Mine Enforcement and Reclamation (DMR) cited the Cambrian Coal Corporation Permit No. 898?0619 (Non-Compliance Number 53-1556) for allowing the sediment level in 88?39 to exceed the cleanout capacity elevation as set forth in the permit plan. This failure to adequately maintain SS-39 further reduced its peak flow reduction capacity. During the January 2011 inspection, F2 noted that 88-33 was constructed with only a spillway and no culvert outlet. The lack of a culvert outlet would signi?cantly reduce capacity to 20 52.612567 FAUIKNER GI Con?dential Attorney Work Product These data con?rm that the sedimentation ponds located on control peak stonnwater ?ows. Cambria :1 Coal Corporation Permit Area 8980619 were inadequate to signi?cantly reduce Peak . Stomiwater ?ows and did not protect against ?ooding during the July 17, 201 stonn. 3.4 CREEK HITRA ULIC MODELING The accuracy of the Hat-less Creek Hydraulic Model was con?rmed by comparing the Computed water surface elevations for july 17, 2010 model storm with three known high July 17, 2010 ?ood. The high water marks were located on three water marks from the structures located within Harless Creek overhank areas that were not destroyed Separate Ont?ght during the july 17, 2010 ?ooding. The elevations of the high water marks were January, 2011 survey data (see Section 1.6). Photographs of the determined based on the high Water mark locations are provided in Appendix 3. At all three locations, the computed total water depths were within 1 to 5% of the measured high water marks. These data con?rm that the Harless Creek hydraulic model accurately represented ?ood flow conditions Within Harless Creek. The Harless Creek hydraulic model was also used to evaluate ?ood ?ows with Harless Creek during the August 11, 2010 storm. On this date F2 observed signi?cant flows within Harless Creek and evidence of minor overtopping of Harless Creek (Appendix 3). According to the Stage II radar data, the August 11, 2010 storm was a 2?year recurrence interval storm. Similarly the Harless Creek hydraulic model results for the 24-hour 2?year recurrence interval storm showed that no ?ooding occurred during the pre?mining condition and minor overtopping of the Harless Creek channel during the current mining land use condition. This is consistent with the results of the Flood Frequency Evaluation (Section 3.2) and con?rms that the Cambrian Coal Corporation and AEP Kentucky Coal, LLC surface mining operations have adversely affected the cumulative hydrologic balance such that ?ooding of Harless Creek will occur more frequently and with greater destructive energy. Representative cross-sections from July 17, 2010 Harless Creek hydraulic model were used to evaluate the water depth, ?ow velocities, and extent of the high danger zones for the right 08X 24/ 11 512.567 21 FAULKNEH Gr Con?dential Attorney Work Product and . . overb??k areas during the pre?mining and current land use conditions (Appendix 4 . - - . The majority of the resrdences impacted by the July 17, 2010 ?ood were located within The high danger zones were delineated based on USBOR published these over-bank areas. . . epth velocity ?ood danger level relationships for passenger vehicles and identify locations Where the combined destructive energy of the ?ood ?ow depths and velocity put lives in . JEDpar-dy, 15) The destructive energy of ?ood ?ows was also evaluated based on the USBOR depth~velocity ?ood danger level relationships for mobile homes and houses built on The Harless Creck hydraulic model results con?rm that the Cambrian Coal Corporaljo? and AEP Kentucky Coal, LLC surface mining operations exacerbated ?ooding during the July 17, 2010 model storm and signi?cantly increased the ?ood?s destructive Energy Within the Harless Creek overbank areas by signi?cantly increasing the depth and velocity of the ?ood ?ows. In summary, Flow Depth: The ?ow depth increased by an average of 1.25 a during the July 17, 2010 model storm due to the Cambrian Coal Corporation and AEP Kentucky Coal, LLC surface mining operations. The increased ?ow depths increased ?ood related damage during the July 17, 2010 ?ood by increasing the area inundated by ?ood waters as well as the destructive energy of the ?ood waters. Flow Velocities: The ?ow velocities in the overbank areas were increased during the july 17, 2010 model storm due to the Cambrian Coal Corporation and AEP Kentucky Coal, LLC surface mining operations. The average velocity for the left and right overbank areas of Harless Creek increased by 53% and 31%, respectively during the current mining condition. This increase in ?ow velocity signi?cantly increased the destructive energy of the July 17, 2010 ?ood and the associated ?ood related damages. High Danger Zone: The increased ?ow depths and velocities within the Harless Creek overbank areas signi?cantly increased the extent of the high danger zone (locations where lives were in danger). The average width of the high danger zone for the left and right overbank areas increased 286% and 156%, respectively. The elevated ?ow depths and velocities created high danger conditions for houses built on foundations, mobile homes and passenger vehicles. The increased peak 22 08/24/11 ?612.56? Con?dential Attorney Work Product Stormwater runoff resulting from Cambrian Coal Corporation and AEP Kentucky C031, LLC surface mining operations increased the high danger zone for the Harless Creek overbank areas, exposed the residents of Hal-less Creek to life-threatening COHditions and exacerbated the destructive energy of the july 17, 2010 ?ood. .ll - I ?3 km in 9693. I . I P?illah?l, Kenn: ?t 5I Irr?sage courtesy aFthe LLB. Geological Survey 1.5' 2010 Microsa?: Corporation. Privacy Statement Terms of Us: FAULKNER 81. FL EHVIIDIHEITIL COHSUL for latitudinal} and iongltudmal coordmatesNew SMDH IN MANIA. 7X5 5.05 wiFJ IDGTI: . 88 aDeaO mF?Db 6 Y5 data-05 chm: .0 ELSE, Hadess Creek Cunant Mining WatershedsL Au. Cambn'an Coal Corporation 8980618 i 8980819 8980619 Cambrian Coal Corporat Ion Cambrian Coal Corporat AE Kentucky Coal, LLC Ion 4 8980660 8980649 - AEP Kentucky 0081. LLC Permi 8. Company namran LIV. HF: FAULKNERGIFL ENVTIONMENTAL MANAGEMENT CONSULTANT HARLESS CREEK WATERSHED FIRE COUNTY, KENTUCKY PERMITTED SURFACE OPERATIONS f? recipitatian [in1.2m 0.40 11:31] {fan 12: 1'5 2-5 2.0 4.0 5'0 571:1 .- SUb-Wate rshed Areas Characteris?cs for the Pro-Mining and Cunent Mining TABLE 2 Land Use Conditions Harless Creek Watershed Pike County, Kentucky Current Mining 0 . Total Com osi Total . Viz-1:913 Area Cuprve te Drainage Mined Mining Coa??o?s?e 1 (acre) Num ber Area (acre) TYPE Numbeer 2 3:3; 23.3 1 36.69 0-00 - i 56.5 3 11001 60.1 65.26 3.50 3 1 63.7 4 76 .26 60.9 4 114.16 2.26 3 1 60.5 . . 74.93 5.47 3 1 62.2 5 31632 62] 5 160.04 13.69 Q0 - 5A 195.66 172.23 3 63.2 6 106.62 60.6 6 105.01 14.56 3 i 52.6 7 33281 61.0 7 130.50 12.15 3 63.2 7A 196.00 177.15 3 64.2 8 112.75 62.6 6 111.69 25.46 1.3 67.7 9 46.94 57.4 9 46.94 7.63 1 i 62.2 10 200.67 37.19 2222+ 66.0 10 307.76 65.2 10A 105.09 60.51 2.3 73.4 1 1 60.63 64.9 11 60.63 50.21 1 67.6 12 17.32 56.7 12 14.91 0.00 - i 56.7 13 26.53 66.1 13 29.73 22.60 1 64.1 14 11.99 57.6 14 10.19 0.00 - 57.6 15 61.65 2.3 66.9 15 180'80 65'8 15A 59.75 3 76.4 16 46.14 67.9 16 49.17 32.66 i 1 64.3 17 287.14 66.2 17 284.97 74.17 2,3 71.8 16 120.22 65.4 16 120.62 46.59 1,2,3 74.4 NOTES: Mining Type 1: Active Strip Mining (CN: 93) 2: Active Contour Mining 3: Reclaimed Mined Areas PDL.612.567 Table 2 Peak Runoff Flows for Representative Sub ABLE 3 -Watershed Areas for the Pr . e-Mlnm - . . Burmg July 17' 201? ?Odd Storm and 2. 5. 10, 15, 50, use commons ?11$ Harless Creek Watershed Pike County, Kentucky Sub-Watershed Area/ pgradient Permitted Surface Mine Area Burnt Tree Land Use Condition Right Fork Slate Frankie Dump Fork Hollow 898-0618 898-0649 898-0518 898-0619 898-0619 8 8?06 - 898-0660 9 49 898-0649 898?0619 898 0619 Z-year Pre-Mining 33 21 48 29 12 Z-year Current Mining Percent Increase (2-year) 186% 1171% 86% 1005% 225% 873% 878% 5~year Pre-Mining 5~year Current Mining 151 383 159 454 75 149 62 Percent Increase (S-Vear) 119% 598% 53% 555% 155% 492% 555% 10?year Pre-Mining 105 94 161 11L 48 15 10-year Current Mining 204 491 228 581 109 180 73% Percent Increase (10-year) 93% 425% 41% 412% 127% 360% 43 Pre?Mining 163 160 253 187 79 62 22 Precipitation Event Oney Fork Harless 55-33!? 55-39?) 25-year PEI cent ?10 ease (ZS-veal) 73% 306% 32% 311% 10590 25390 338% 29 Pre?Mining 217 226_ 339 82 a 73; ?"455 ?933 211 ?251 115 50-year Current Mining 353 93% 217% 294% ent Increase (50?year) 63% 251% 27% 264% 277 Pre-Mmmg 14 263 534 11 100 year Current Mining 429 942 230% 85% #13496 25329.6 100 Percent Increase (loo-year) 276 365 ?51? 15? . 7?54 1179/ 134%; MW 109% 14% 105% 37% 4 6 38 300 434 33g? 142: 10 loo-year 55% 214% 23% - 1 7/17/2010 514 793 209 2 Percent Increase (July 17, 2010) Change in Peak Flow an 5 .10 25 (4 24-Hour Recurrence Interval Storm Annual Probability . (Chance)} Peak Flow (cfs) - Pre-Mining Flooding Risk from Pre- 50 and 100 1 Year (100%) Pike County, Kentucky 2 years TABLE 4 Mining and Curr Year Recurrence Harless Creek Water shed a 5 years 10 years ent Mining Conditions based a 1 2 Storm Event nterval SCS 24-Hour 25 years 50 years 100 years Land Use Condition Peak Flow (cfs) - Current 100 262 600 958 1551 2117 2752 Mining Land Use Condition Pro-Mining Flood Plain Based 563 912 1510 2074 2946 3733 4590 on Pre-Mining Land Use Condition (Year) Flooding Frequency of Pre- 10 25 50 100 Mining Floodplain Based on Current Mining Land Use Conditon (Year) <1 <1 1.1 2.2 5.4 11.2 21.7 Increase Flooding Risk from 200% 200% 450% 470% 470% 460%