Allegheny Energy

R. Paul Smith Station

Williamsport, MD

Prepared for

Lockheed Martin

2890 Woodridge Ave #209

Edison, New Jersey 08837

April 21, 2010

  

CHA Project No. 20085.1020.1510

Assessment of Dam Safety

Coal Combustion Surface Impoundments (Task 3)

Final Report

 -iii- Final Report 

Assessment of Dam Safety of 

Coal Combustion Surface Impoundments 

 Allegheny Energy 

R. Paul Smith Station 

Williamsport, Maryland & 

Falling Waters, West Virginia 

TABLE OF CONTENTS 

SECTION PAGE NUMBER 

1.0 INTRODUCTION & PROJECT DESCRIPTION........................................................ 1 

1.1 Introduction............................................................................................................. 1 

1.2 Project Background................................................................................................. 2 

1.2.1 State Issued Permits ................................................................................................ 2 

1.3 Site Description and Location................................................................................. 2 

1.3.1 Ash Pond #3............................................................................................................ 3 

1.3.2 Ash Pond #4............................................................................................................ 4 

1.3.3 Other Impoundments .............................................................................................. 4 

1.4 Previously Identified Safety Issues......................................................................... 4 

1.5 Site Geology............................................................................................................ 5 

1.6 Bibliography ........................................................................................................... 5 

2.0 FIELD ASSESSMENT................................................................................................... 13 

2.1 Visual Observations.............................................................................................. 13 

2.2 Visual Observations – Ash Pond #3 ..................................................................... 14 

2.2.1 Ash Pond #3 – Embankments and Crest............................................................... 14 

2.2.2 Ash Pond #3 – Outlet Control Structure............................................................... 15 

2.3 Visual Observations – Ash Pond #4 ..................................................................... 16 

2.3.1 Ash Pond #4 – Embankments and Crest............................................................... 16 

2.3.2 Ash Pond #4 – Outlet Control Structure............................................................... 18 

2.4 Monitoring Instrumentation.................................................................................. 18 

3.0 DATA EVALUATION ................................................................................................... 46 

3.1 Design Assumptions ............................................................................................. 46 

3.2 Hydrologic and Hydraulic Design ........................................................................ 46 

3.2.1 Ash Pond #3 – Hydrologic and Hydraulic Design................................................ 46 

3.2.2 Ash Pond #4 – Hydrologic and Hydraulic Design................................................ 47 

3.2.3 Flooding from the Potomac River......................................................................... 47 

3.3 Structural Adequacy & Stability........................................................................... 49 

3.3.1 Ash Pond #3 – Structural Adequacy & Stability .................................................. 49 

3.3.2 Ash Pond #4 – Structural Adequacy & Stability .................................................. 52 

3.3.3 Instrumentation Review Relative to Stability....................................................... 53 

3.4 Operations, Maintenance, and Inspections ........................................................... 54 

3.4.1 Inspection Procedures ........................................................................................... 54 

3.4.2 Inspections by West Virginia Dam Safety............................................................ 55 

3.4.3 Maintenance.......................................................................................................... 55 

3.5 Foundation Conditions.......................................................................................... 56 

4.0 CONCLUSIONS/RECOMMENDATIONS ................................................................. 67 

4.1 Acknowledgement of Management Unit Condition............................................. 67 

4.2 Upstream Slopes ................................................................................................... 67 
 -iv- Final Report 

Assessment of Dam Safety of 

Coal Combustion Surface Impoundments 

 Allegheny Energy 

R. Paul Smith Station 

Williamsport, Maryland & 

Falling Waters, West Virginia 

TABLE OF CONTENTS - continued 

SECTION PAGE NUMBER 

4.3 Downstream Slopes on Ash Pond #4.................................................................... 68 

4.4 Tree Removal on Ash Pond #3 Buttress............................................................... 68 

4.5 Monitoring Instrumentation.................................................................................. 69 

4.6 Evaluation of Conditions from Potomac River Flooding ..................................... 69 

5.0 CLOSING ........................................................................................................................ 70 

TABLES 

Table 1 - Approximate Precipitation Prior to Site Visit ............................................................... 13 

Table 2 - Ash Pond #3 Soil Parameters Used in Stability Analyses............................................. 50 

Table 3 - Ash Pond #3 Engineering Comparison to Design Criteria............................................ 50 

Table 4 - Ash Pond #4 Soil Parameters Used in Stability Analyses............................................. 52 

Table 5 - Ash Pond #4 Engineering Comparison to Design Criteria............................................ 53 

LIST OF FIGURES

Figure 1- Project Location Map...................................................................................................... 7 

Figure 2 - Photo Site Plan ............................................................................................................... 8 

Figure 3 - Critical Infrastructure Map............................................................................................. 9 

Figure 4A - Typical Cross Section Ash Pond #3 North Dike....................................................... 10 

Figure 4B - Typical Cross Section Ash pond #3 East Dike.......................................................... 11 

Figure 5 - Typical Cross Section Ash Pond #4............................................................................. 12 

Figure 6A - Photo Location Plan Ash Pond #3............................................................................. 19 

Figure 6B - Photo Location Plan Ash Pond #4............................................................................. 20 

Figure 7A - Stability Analyses Ash Pond #3................................................................................ 57 

Figure 7B - Stability Analyses Ash Pond #3 Dam ....................................................................... 58 

Figure 8A - Stability Analyses Ash Pond #4................................................................................ 59 

Figure 8B - Stability Analyses Ash Pond #4 ................................................................................ 60 

Figure 8C - Stability Analyses Ash Pond #4 ................................................................................ 61 

Figure 8D - Stability Analyses Ash Pond #4................................................................................ 62 

Figure 8E - Stability Analyses Ash Pond #4 ................................................................................ 63 

Figure 8F - Stability Analyses Ash Pond #4................................................................................. 64 

Figure 8G - Stability Analyses Ash Pond #4................................................................................ 65 

Figure 8H - Stability Analyses Ash Pond #4................................................................................ 66 

APPENDIX 

Appendix A - Completed EPA Coal Combustion Dam Inspection Checklist Forms & Completed 

EPA Coal Combustion Waste (CCW) Impoundment Inspection Forms 
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Assessment of Dam Safety of 

Coal Combustion Surface Impoundments 

 Allegheny Energy 

R. Paul Smith Station 

Williamsport, Maryland & 

Falling Waters, West Virginia 

1.0 INTRODUCTION & PROJECT DESCRIPTION 

1.1 Introduction 

CHA was contracted by Lockheed Martin (a contractor to the United States Environmental 

Protection Agency) to perform site assessments of selected coal combustion surface 

impoundments (Project #0-381 Coal Combustion Surface Impoundments/Dam Safety 

Inspections). As part of this contract, CHA was assigned to perform a site assessment of 

Allegheny Energy’s Ash Pond #3 and Ash Pond #4 at the R. Paul Smith Power Station. The 

Power Station is located in Williamsport, Maryland, and the ash lagoons are in Falling Waters, 

West Virginia as shown on Figure 1 – Project Location Map. 

CHA made a site visit on October 20, 2009 to inventory coal combustion surface impoundments 

at the facility, perform visual observations of the containment dikes, and collect relevant 

information regarding the site assessment. 

CHA Engineers Katherine Adnams, P.E., and Khalid Abed, P.E. were accompanied by the 

following individuals: 

Company or Organization Name and Title 

Allegheny Energy Gary Haag, Environmental Manager 

Allegheny Energy Erik Johnsson, Engineer 

Allegheny Energy Mark Vindivich, Manager Production 

GAI Consultants Barry Newman, PE, Vice President – Geotechnical and 

Structural Engineering 
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Assessment of Dam Safety of 

Coal Combustion Surface Impoundments 

 Allegheny Energy 

R. Paul Smith Station 

Williamsport, Maryland & 

Falling Waters, West Virginia 

1.2 Project Background 

Ash Ponds #3 and #4 are under the jurisdiction of the State of West Virginia Department of 

Environmental Protection (WVDEP). According to the West Virginia Title 47 Legislative Rule, 

Series 34 Dam Safety Rule, the dikes for these impoundments have a Hazard Classification of 

Class 2 (Significant Hazard) meaning the failure of the dam may cause minor damage to 

dwellings, commercial or industrial buildings, important public utilities, main railroads, or cause 

major damage to unoccupied buildings, or where a low risk highway may be affected or 

damaged. The potential for loss of human life resulting from failure must be unlikely. 

1.2.1 State Issued Permits 

Ash Ponds #3 and #4 were constructed prior to WVDEP requiring Certificates of Approval, 

which became a requirement in 1992. Allegheny Energy received a Certificate of Approval for 

Ash Pond #3 in 1996 and another in 1999 for repair to the outlet works. 

Allegheny Energy received an initial Certificate of Approval for work at Ash Pond #4 in 1981, 

and another in 1997 for repair to the outlet works. 

A National Pollutant Discharge Elimination System (NPDES) permit, MD0000582 has been 

issued to Allegheny Energy authorizing discharge to the Potomac River in accordance with 

effluent limitations, monitoring requirements and other conditions set forth in the permit. The 

permit became effective on August 16, 2008 and is set to expire on July 16, 2013. 

1.3 Site Description and Location 

Ash Ponds #3 and #4 (also referred to in some documents as Lagoons #3 and #4) are located on 

the west bank of the Potomac River in Falling Waters, West Virginia. Pond #3 is located to the 

north of Pond #4. Figure 2 shows a site plan, and Figures 3 and 4 shows a typical cross section 
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Assessment of Dam Safety of 

Coal Combustion Surface Impoundments 

 Allegheny Energy 

R. Paul Smith Station 

Williamsport, Maryland & 

Falling Waters, West Virginia 

of the dams. Allegheny Energy alternates use of the ponds, pumping to one until it is full, and 

then switching to the other while the full impoundment is dewatered and dredged with the ash 

taken to a nearby landfill. 

A map of the region indicating the location of the R. Paul Smith Power Station and Ash Ponds 

#3 and #4 identifying schools, hospitals, or other critical infrastructure located within 

approximately five miles down gradient of the ash pond is provided as Figure 3. The community 

of Falling Waters, West Virginia is about 5 miles downstream from the dam. 

1.3.1 Ash Pond #3 

Ash Pond #3 is impounded on three sides (north, east, and south) by an earthen embankment 

dike. The west side is impounded by natural topography. The Ash Pond #3 dikes have a 

maximum height of approximately 46 feet resulting in a maximum storage capacity of 104 acrefeet. The east dike is buttressed with rock fill, while the north and south dike sections are 

armored with rock fill, but not buttressed (i.e., the rock fill was not placed to contribute to the 

structural stability). The toe of the east dike buttress extends approximately to the shoreline of 

the Potomac River at normal water level in the river. The water level in Lagoon #3 is controlled 

by an HDPE spillway riser pipe at the south end of the lagoon. Originally constructed in the 

1960s (exact year unknown) this impoundment has been modified several times; in 1980 the 

crest of the dike was raised after flooding of the Potomac River related to Hurricane Agnes 

(1972) came near the dam crest elevation, and in 1999 the corrugated metal pipe (CMP) outlet 

corroded through and caused increased flow through the discharge. Repair work was performed 

in 1999 without release of CCW. Figures 4A and 4B show typical cross sections of the Ash 

Pond #3 dikes. 
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Assessment of Dam Safety of 

Coal Combustion Surface Impoundments 

 Allegheny Energy 

R. Paul Smith Station 

Williamsport, Maryland & 

Falling Waters, West Virginia 

1.3.2 Ash Pond #4 

Ash Pond #4 is impounded on three sides (north, east, and south) by an embankment dike. The 

west side is impounded by natural topography. The Potomac River lies approximately 70 to 100 

feet east of the lagoon. The Ash Pond #4 dikes have a maximum height of approximately 41 feet 

resulting in a maximum storage capacity of 218 acre-feet. The dikes have downstream slopes of 

about 2H:1V, and upstream slopes of about 1.7H to 2H:1V. The upstream slope is partially lined 

with a hypalon geosynthetic liner. The downstream slope is grasses and weedy vegetation. The 

water level in Ash Pond #4 is controlled by an HDPE spillway riser pipe at the south end of the 

spillway. Originally constructed in the early 1960s (exact year unknown) this impoundment had 

repairs performed in 1997 on the spillway outlet pipe after corrosion through the CMP outlet 

pipe resulted in increased flows discharging from the pond. Figure 5 shows a typical cross 

section of the Ash Pond #4 dikes. 

1.3.3 Other Impoundments 

There were no other impoundments observed at the R. Paul Smith Power Station Site. CHA 

inquired as to whether Ponds #1 and #2 existed, and Allegheny Energy responded that these were 

formerly in Maryland at the physical plant site and that they were retired in the 1960s. Pond #1 

was removed and Pond #2 was filled with soil and grass covered. 

 

1.4 Previously Identified Safety Issues 

In 1997 and 1999, failures of the original CMP outlet pipes occurred in Ash Pond #4 and Ash 

Pond #3, respectively. Routine observations by plant personnel found increased flows from the 

outlet pipes, which suggested failure within the outlet structure. During each situation, 

Allegheny Energy hired an outside consultant to investigate where the failure had occurred and 

develop repairs to be implemented. In both cases, the riser structure was replaced with a 42-inch 
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Assessment of Dam Safety of 

Coal Combustion Surface Impoundments 

 Allegheny Energy 

R. Paul Smith Station 

Williamsport, Maryland & 

Falling Waters, West Virginia 

diameter HDPE riser, and the 18-inch CMP pipes were slip lined with 14-inch HDPE pipes with 

the annulus between CMP and HDPE grouted. 

Based on our review of the information provided to CHA and as reported by Allegheny Energy, 

there have been no additional safety issues identified at Ponds #3 and #4 in the last 10 years. 

1.5 Site Geology 

According to U.S. Geological Survey Open-File Report 01-188, Geology of the Chesapeake and 

Ohio Canal National Historical Park and Potomac River Corridor, District of Columbia, 

Maryland, West Virginia, and Virginia, the geology of the area of Ponds #3 and #4 is likely 

shale, siltstone and sandstone bedrock with possible layers of limestone within the Great Valley 

geologic region. This region is likely part of the Martinsburg formation which is surrounded by 

other geologic formations of limestone and dolomite formations that include abundant caves and 

sinkholes. The bedrock is overlain by Holocene and Pleistocene era terraces of sand, gravel and 

boulders, and Holocene era alluvium consisting of unconsolidated clay, silt, sand and gravel 

underlying modern era floodplains. 

CHA observed road signs in Falling Waters, West Virginia indicating that sinkholes due to karst 

topography were common, but did not see evidence of such features at the Ash Pond sites. 

1.6 Bibliography 

CHA reviewed the following documents provided by WVDEP and Allegheny Energy in 

preparing this report: 

 R. Paul Smith Power Station, Lagoon/Dam No. 3, letter from GAI Consultants, March 

13, 2009. 
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Assessment of Dam Safety of 

Coal Combustion Surface Impoundments 

 Allegheny Energy 

R. Paul Smith Station 

Williamsport, Maryland & 

Falling Waters, West Virginia 

 Results of Supplemental Stability Analyses, Wastewater Treatment/Ash Storage 

Lagoon/Dam No. 4, GAI Consultants, October 2009. 

 Order of Compliance, issued by West Virginia Department of Environmental Protection, 

January 30, 2009. 

 Modification to Certificate of Approval – Outlet Works Reconstruction, Lagoon No. 4, SE 

Technologies, September 1997. 

 Outlet Works Reconstruction Wastewater/Ash Storage Lagoon No. 3, GAI Consultants, 

January 1999. 

 WVDEP Inspection Reports for R. Paul Smith Power Station Lagoons #3 and #4, 

WVDEP 2009, 2006. 

 Biannual Independent Consultant Inspection Report – R. Paul Smith Power Station 

Lagoons #3 and #4, Various consultants, 2004, 2006, 2008, 2009. 

 Dam Safety Maintenance Plans for Wastewater/Ash Storage Lagoons No. 3 and No.4, 

Allegheny Energy, May 2006. 
Figure 1 

Project Location Map 

Allegheny Energy 

R. Paul Smith Station 

Williamsport, MD 

Scale: 1" = 1 mile Project No.: 

20085.1020.1510 

R. Paul Smith Station

IMAGE DATE: 07/01/1981 
ASH POND #3

R. PAUL SMITH STATION

ALLEGHENY

ENERGY

LANDFILL

ASH POND #4

POTOMAC RIVER SMALTZ DR
R. PAUL SMITH STATION

ASH POND #3

ASH POND #4 POTOMAC RIVER

FLOW

ORIGINAL DOWNSTREAM SLOPE

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Assessment of Dam Safety of 

Coal Combustion Surface Impoundments 

 Allegheny Energy 

R. Paul Smith Station 

Williamsport, Maryland & 

Falling Waters, West Virginia 

2.0 FIELD ASSESSMENT 

2.1 Visual Observations 

CHA performed visual observations of Ash Ponds #3 and #4 following the general procedures 

and considerations contained in Federal Emergency Management Agency’s (FEMA’s) Federal 

Guidelines for Dam Safety (April 2004), and Federal Energy Regulatory Commission (FERC) 

Part 12 Subpart D to make observations concerning settlement, movement, erosion, seepage, 

leakage, cracking, and deterioration. A Coal Combustion Dam Inspection Checklist and Coal 

Combustion Waste (CCW) Impoundment Inspection Form, prepared by the US Environmental 

Protection Agency, were completed on-site during the site visit. Copies of the completed forms 

were submitted via email to a Lockheed Martin representative approximately three days 

following the site visit to the R. Paul Smith Power Station. Copies of these completed forms are 

included in Appendix A. Photo logs and Site Photo Location Plan (Figures 6A and 6B) for Ash 

Ponds #3 and #4 are located at the end of Section 2.4. 

CHA’s visual observations were made on October 20, 2009. The weather was sunny with 

temperatures between 40 and 70 degrees Fahrenheit. Prior to the days we made our visual 

observations, the following approximate rainfall amounts occurred (as reported by 

www.weather.com). 

Table 1– Approximate Precipitation Prior to Site Visit 

Date of Site Visit – October 20, 2009 

Day Date Precipitation (inches) 

Monday October 13, 2009 Trace 

Tuesday October 14, 2009 0.00 

Wednesday October 15, 2009 0.56 

Thursday October 16, 2009 0.15 

Friday October 17, 2009 0.45 

Saturday October 18, 2009 0.06 

Sunday October 19, 2009 0.00 

Total Week Prior to Site Visit 1.22 

Total 30 Days Prior to Site Visit 1.80 
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Assessment of Dam Safety of 

Coal Combustion Surface Impoundments 

 Allegheny Energy 

R. Paul Smith Station 

Williamsport, Maryland & 

Falling Waters, West Virginia 

2.2 Visual Observations – Ash Pond #3 

CHA performed visual observations of Ash Pond #3. Ash Pond #3 is about 1,700 feet long with 

a maximum height of 46 feet. The pond is impounded by dikes on the north, east and south 

sides, and by natural ground on the west side. 

2.2.1 Ash Pond #3 – Embankments and Crest 

In general, the alignments of the crest of Ash Pond #3 dikes do not show signs of change in 

horizontal alignment. The crest is typically about 12 feet wide and is grass covered as shown in 

Photos 2, 6, and 15. The crest is slightly wider at the west end of the north dike because of ash 

left against the upstream slope during past dredging operations. 

The upstream slope is grass covered to the elevation corresponding to maximum storage, and 

exposed ash below that elevation due to recent 2008 dredging operations. The upstream slope of 

the north dike is shown in Photo 4, the upstream slope of the east dike is shown in Photo 7, and 

the upstream slope of the south dike is shown in Photos 16 and 17. The north end of the east 

dike was over excavated to an overly steep slope during recent dredging operations. This over 

excavation during dredging operations appears, from reports reviewed, to occur frequently. The 

2009 GAI report notes that this condition was discussed in a 1978 and 1995 stability reports. 

Non-disturbed slopes are about 3H:1V. A bench remains in the southeast corner of the pond 

adjacent to the outlet structure. This bench is a remnant of access ramps constructed to perform 

upgrades to the outlet structure in 1999. The upstream slope between the top of the ramp and the 

crest of the dike is quite steep, with contours on a May 2009 survey showing the slope at about 

1.3 to 1.4 horizontal to 1 vertical. The remaining portions of the south dike upstream slope are 

about 2.5H:1V. 
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Assessment of Dam Safety of 

Coal Combustion Surface Impoundments 

 Allegheny Energy 

R. Paul Smith Station 

Williamsport, Maryland & 

Falling Waters, West Virginia 

The downstream slope is armored with rip rap generally about 6 to 8 inches in diameter. The 

east dike is buttressed with an approximately 20- to 25-foot wide stone bench which then slopes 

to the shore of the Potomac River. Access to the downstream slope of the buttress is hindered by 

tree growth and the proximity to the river, with some sections of the buttress extending to the 

water line, while in other areas there was a narrow strip of shoreline beyond the toe of slope. 

Photo 5 shows the downstream slope of the north dike, Photos 8, 11 and 12 show the 

downstream slope of the east dike, Photos 9, 10 and 14 show the east dike buttress, and Photos 

18, 19 and 20 show the downstream slope of the south dike. In general the dike slope was free of 

vegetation, although areas of grass had established along the south dike. 

An area of possible seepage has been noted and observed in past inspection reports about 35 feet 

from the toe of the south dike near the outlet pipe discharge point. This area is shown in Photos 

21 and 22. CHA did not observe flow or deposition of sediment in the seepage area, and 

Allegheny Energy indicated that it is likely related to natural drainage between Ponds #3 and #4, 

but that they had not definitively determined this so they continue to make observations as if it 

were seepage. The ground surface in this seepage area is about 4 feet below the elevation of 

standing water in the recently dredged pond that was observed in the pond during CHA’s visit. 

2.2.2 Ash Pond #3 – Outlet Control Structure 

Ash Pond #3 discharges through an HDPE decant structure with multiple ports in the riser as 

shown in Photo 16. As the water/ash level rises when the pond is in service, Allegheny Energy 

personnel install blind flanges when they are ready to raise the level to the next port. This riser 

discharges below the south dike via a 14-inch HDPE which was sliplined into the original 18-

inch CMP pipe. The discharge end of the pipe is shown in Photo 23. It discharges into a 

Fabriform® lined channel which discharges to the Potomac River as shown in Photo 24. 
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Assessment of Dam Safety of 

Coal Combustion Surface Impoundments 

 Allegheny Energy 

R. Paul Smith Station 

Williamsport, Maryland & 

Falling Waters, West Virginia 

2.3 Visual Observations – Ash Pond #4 

Ash Pond #4 is about 2,020 feet long with a maximum height of 41 feet. The pond is impounded 

by dikes on the north, east and south sides, and by natural ground on the west side. 

2.3.1 Ash Pond #4 – Embankments and Crest 

In general, the alignments of the crest of Ash Pond #4 dikes do not show signs of change in 

horizontal alignment. The crest is about 10 feet wide and is grass covered as shown in Photos 27, 

33, 34 and 42. The surface has moderate rutting from vehicle traffic on the crest. An 

approximately 14-inch diameter, 2-inch deep depression was observed on the crest in the area 

where the discharge pipe passes beneath the east dike. The discharge pipe was slip-lined in 

1997, as described in Section 1.3.2. 

The upstream slope at the east end of the north and south dikes, and the entire length of the east 

dike is lined with a hypalon liner as shown in Photos 29, 33, and 43. Reports reviewed by CHA 

indicated this liner was installed in 1981 to control the phreatic surface within the embankment 

to maintain adequate slope stability. Allegheny Energy maintains the liner, routinely patching 

small holes made by animals walking on the liner as shown in Photo 30. The western ends of the 

north and south dike are covered with weedy vegetation, which had been freshly cut prior to our 

site visit. The surface of vegetated upstream slope on the north dike was soft to about 18 inches 

and irregularly graded. Allegheny Energy indicated that some of the soft material was likely ash 

left after various dredging operations that became weed covered. This slope is shown in Photos 

27 and 28. The vegetated portion of the upstream slope on the south dike is steep and Allegheny 

Energy indicated that this slope will be regraded and buttressed as part of upcoming work to be 

performed when the pond is next taken out of service (i.e., when they switch to sluicing ash into 

Pond #3). 
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Assessment of Dam Safety of 

Coal Combustion Surface Impoundments 

 Allegheny Energy 

R. Paul Smith Station 

Williamsport, Maryland & 

Falling Waters, West Virginia 

The downstream slopes are weed covered which was freshly cut at the time of our site visit. 

Photo Nos. 31, 35, and 46 show the general condition of the downstream slope. Many features 

of deterioration of the downstream slopes were noted as listed below: 

• Several areas of surface erosion and sloughing were observed. Near the northeast corner, 

surface erosion has occurred at the fence line as shown in Photo 36. This feature was 

noted in previous inspection reports and according to Allegheny Energy personnel, has 

remained unchanged in many years. A similar area of surface erosion was noted near 

location marking tag #30. Between marking tags #56 and #57, a clump of woody 

vegetation stumps appeared to be inhibiting sheet flow along the slope surface but rather 

forcing erosion rills to develop around it. 

• A bench with a top elevation about 2 feet lower than the crest that is located near the 

middle portion of the east dike appeared to have a surface slump with bulging and 

steepening of the toe. This feature was located near location marking tag #48. 

• In general the surface soils on the east downstream slope were soft, and shifted when 

walked on. Significant rain had been received in the week preceding our site visit and 

Allegheny Energy personnel indicated that some of the surface sloughing such as that 

shown in Photo 38 may have occurred while contractor crews were weed-whacking the 

slope. 

• The natural slope between the toe of the Ash Pond #4 dike and the Potomac River is 

covered with trees. For the most part, these trees start at the toe of the dike. However, in 

a few locations, such as that shown in Photo 37, large trees are actually within the toe of 

the east dike. Low hanging branches from these trees beyond the toe of the dike are 

encroaching on the dike as shown in Photo 40. Small shrubs were observed on the south 

dike as shown in Photo 47. 

• Filled in rodent holes were observed on the downstream slopes as shown in Photo 39. 

Allegheny Energy described burrowing rodents as an ongoing problem at this site, and 

that they routinely fill rodent burrows as found, and each spring perform rodent control 
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Assessment of Dam Safety of 

Coal Combustion Surface Impoundments 

 Allegheny Energy 

R. Paul Smith Station 

Williamsport, Maryland & 

Falling Waters, West Virginia 

finding that performing removal of the animals around mating season has had a positive 

impact on gaining control on the rodent population. 

CHA did not observe seepage and the drainage swale at an apparent toe drain along the south 

dike was dry. CHA also took a reading in a piezometer at about the mid point of the east dike, 

which indicated water in the dike was between 28 and 30 feet below the crest surface. The dike 

in this area is about 22 feet high. Allegheny Energy’s consultant, GAI Consultants, indicated 

that they had found similar piezometer readings during a 2009 review of the stability of the Ash 

Pond #4 dike, which is more thoroughly discussed in Section 3.3.2. 

2.3.2 Ash Pond #4 – Outlet Control Structure 

Ash Pond #4 discharges through an HDPE riser in the southeast corner of the pond as seen in 

Photo 48. Allegheny Energy indicated this structure was the same as the one observed in Ash 

Pond #3. At the time of CHA’s site visit the water level in Ash Pond #4 was at the top crest of 

the decant structure. The decant structure discharges beneath the east dike through a 14-inch 

diameter HDPE sliplined into the original CMP pipe as described in Section 1.3.2. The 

discharge end of the pipe is seen in Photo 49 and discharges into a rip rap lined channel to the 

Potomac River as shown in Photo 50. 

2.4 Monitoring Instrumentation 

There are a few piezometers on the Ash Pond #4 dikes. These piezometers were installed in 

1997 as part of the outlet riser repair project, and have not been monitored until 2009 when they 

were used by GAI to determine the phreatic surface in the dam for stability analyses to meet 

requirements of a WVDEP Order of Compliance issued in the wake of the TVA Kingston event. 

There is no monitoring instrumentation on Ash Pond #3 dikes. 
1

2

3

7

4

5

6

12

13

14

10

8

9

17

16

11

15 24

23

21, 20

22

19

18
46

45

44

47

43

42 41 48

37

49

50

34

35

40

36 33

29

31

32

27

25 26

28
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Pond #3, looking southeast from the north abutment. West side of pond (right side of photo) is in natural ground.

 

Crest of north dike at Pond #3, looking east. 

ALLEGHENY ENERGY 

R. PAUL SMITH STATION 

POND #3 

WILLIAMSPORT, MD

CHA Project No.: 20085.1020.1510 October 20, 2009 

1 

2 
Page 22 

Upstream slope of north dike at Pond #3, looking east. 

Irregularity of slope related to remaining ash from recent dredging operations.

 

Upstream slope of north dike at Pond #3, looking west. Pond was dredged in 2008. 

ALLEGHENY ENERGY 

R. PAUL SMITH STATION 

POND #3 

WILLIAMSPORT, MD

CHA Project No.: 20085.1020.1510 October 20, 2009 

3 

4 
Page 23 

Downstream slope of north dike at Pond #3, looking west towards north abutment.

 

Crest of east dike at Pond #3, looking south 

ALLEGHENY ENERGY 

R. PAUL SMITH STATION 

POND #3 

WILLIAMSPORT, MD

CHA Project No.: 20085.1020.1510 October 20, 2009 

5 

6 
Page 24 

Upstream slope of east dike at Pond #3, looking south. Irregularity in 

slope related to over excavation during recent dredging operations. 

 

Downstream slope of east dike at Pond #3 looking north.

ALLEGHENY ENERGY 

R. PAUL SMITH STATION 

POND #3 

WILLIAMSPORT, MD

CHA Project No.: 20085.1020.1510 October 20, 2009 

7 

8 
Page 25 

Trees growing in stone buttress on east dike of Pond #3, looking north.

 

Stone buttress on east dike of Pond #3 extends to the edge of the Potomac River. 

ALLEGHENY ENERGY 

R. PAUL SMITH STATION 

POND #3 

WILLIAMSPORT, MD

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Downstream slope of east dike at Pond #3, looking north.

 

Sluice lines from R. Paul Smith Station at northeast corner of Pond #3 service both Pond #3 and Pond #4. 

Hardened steel lines to dike crest and they are replaced approximately every 15 years as routine maintenance. 

ALLEGHENY ENERGY 

R. PAUL SMITH STATION 

POND #3 

WILLIAMSPORT, MD

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Slice lines from R. Paul Smith Station traverse the Potomac River are hardened steel and protected with rip rap. 

The sluice lines are replaced approximately every 15 years as routine maintenance.

 

Stone buttress looking south from northeast corner of Pond #3.

ALLEGHENY ENERGY 

R. PAUL SMITH STATION 

POND #3 

WILLIAMSPORT, MD

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Crest of south dike at Pond #3, looking west toward south abutment.

 

Upstream slope of south dike of Pond #3 looking south and decant structure. 

Bench is remnant of an access road built when the decant structure was replaced in 1997.

ALLEGHENY ENERGY 

R. PAUL SMITH STATION 

POND #3 

WILLIAMSPORT, MD

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Upstream slope of south dike of Pond #3 looking southwest. South abutment at right of photo.

 

Downstream slope of south dike of Pond #3, looking east. 

ALLEGHENY ENERGY 

R. PAUL SMITH STATION 

POND #3 

WILLIAMSPORT, MD

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Downstream slope of south dike of Pond #3, looking east.

 

Typical patchy vegetation on rip rap armor of downstream slopes of Pond #3. Mostly grasses, occasional saplings.

ALLEGHENY ENERGY 

R. PAUL SMITH STATION 

POND #3 

WILLIAMSPORT, MD

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Possible (and previously noted) seepage area south of south dike of Pond #3 looking north. 

Possibly related to natural drainage between Ponds #3 and #4.

 

Close up of possible seepage area. No obvious flow and no observed deposition of sediment. 

ALLEGHENY ENERGY 

R. PAUL SMITH STATION 

POND #3 

WILLIAMSPORT, MD

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Outlet pipe from the decant structure. Pond currently dewatered/dredged below the decant elevation.

 

Fabriform lined discharge channel from Pond #3 to the Potomac River.

ALLEGHENY ENERGY 

R. PAUL SMITH STATION 

POND #3 

WILLIAMSPORT, MD

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West side of Pond #4 is in natural ground, looking south.

 

Pond #4, looking southeast. 

ALLEGHENY ENERGY 

R. PAUL SMITH STATION 

POND #4 

WILLIAMSPORT, MD

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Crest of the north dike at Pond #4, looking east.

Upstream slope of north dike at Pond #4, looking northeast. 

ALLEGHENY ENERGY 

R. PAUL SMITH STATION 

POND #4 

WILLIAMSPORT, MD

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Hypalon liner on the upstream slope of the north dike at Pond #4.

 

Routine maintenance includes patching holes on the hypalon liner created by animals walking on the liner. 

ALLEGHENY ENERGY 

R. PAUL SMITH STATION 

POND #4 

WILLIAMSPORT, MD

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Downstream slope of north dike at Pond #4, looking north.

 

Sluice lines at north abutment.

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R. PAUL SMITH STATION 

POND #4 

WILLIAMSPORT, MD

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Crest of east dike at Pond #4, looking south.

 

Crest of east dike at Pond #4, looking south. 

ALLEGHENY ENERGY 

R. PAUL SMITH STATION 

POND #4 

WILLIAMSPORT, MD

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Downstream slope of east dike at Pond #4, looking south.

 

Surface erosion at downstream slope/crest on east dike at Pond #4. 

This erosion has been noted in previous inspection reports and has not changed in many years. 

ALLEGHENY ENERGY 

R. PAUL SMITH STATION 

POND #4 

WILLIAMSPORT, MD

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Large tree at toe of east dike slope at Pond #4, looking north.

 

Erosion/surficial sloughing on east dike at Pond #4. Surface soil soft.

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R. PAUL SMITH STATION 

POND #4 

WILLIAMSPORT, MD

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Filled in rodent holes on east dike at Pond #4. Rodent control is performed each 

spring and observed holes are filled as part of routine maintenance of the dikes.

 

Adjacent tree branches near east dike slope at Pond #4.

ALLEGHENY ENERGY 

R. PAUL SMITH STATION 

POND #4 

WILLIAMSPORT, MD

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Depression about 2 inches deep and 18 inches in diameter on crest of east dike in approximate area of outlet pipe.

 

Crest at southeast corner of Pond #4. 

ALLEGHENY ENERGY 

R. PAUL SMITH STATION 

POND #4 

WILLIAMSPORT, MD

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Upstream slope of south dike at Pond #4, looking southwest.

 

Upstream slope of south dike at Pond #4, looking east.

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R. PAUL SMITH STATION 

POND #4 

WILLIAMSPORT, MD

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Upstream slope of the south dike at Pond #4, looking west toward the south abutment.

 

Downstream slope of the south dike at Pond #4, looking east. 

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R. PAUL SMITH STATION 

POND #4 

WILLIAMSPORT, MD

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Small trees on downstream slope on south dike at Pond #4, looking east.

 

Decant structure in the southeast corner of Pond #4.

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R. PAUL SMITH STATION 

POND #4 

WILLIAMSPORT, MD

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Discharge pipe from Pond #4.

 

Rip rap channel from the Pond #4 outlet to the Potomac River.

ALLEGHENY ENERGY 

R. PAUL SMITH STATION 

POND #4 

WILLIAMSPORT, MD

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 -46- Final Report 

Assessment of Dam Safety of 

Coal Combustion Surface Impoundments 

 Allegheny Energy 

R. Paul Smith Station 

Williamsport, Maryland & 

Falling Waters, West Virginia 

3.0 DATA EVALUATION 

3.1 Design Assumptions 

CHA has reviewed the design assumptions related to the design and analysis of the stability and 

hydraulic adequacy of the Ash Ponds #3 and #4, which were available at the time of our site 

visits and provided to us by Allegheny Energy. The design assumptions are listed in the 

following sections. 

3.2 Hydrologic and Hydraulic Design 

Dams in West Virginia are governed by West Virginia Rule 47CSR34. Under this legislation the 

Ash Ponds #3 and #4 are classified as Class 2, significant hazard, dams. This classification 

requires the dam to safely pass or store the inflow from 50 percent of the 6-hour duration 

Probable Maximum Precipitation (PMP), discharge 90% of the stored storm volume within 10 

days after the storm event, and emergency spillway operation frequency shall be no more than 

once in 50 years, if included. Ash Ponds #3 and #4 were constructed with only primary drop 

inlet type spillways and do not have emergency spillways. In this case the West Virginia 

regulations require that the impoundment have adequate storage to contain the full inflow from 

the design storm (i.e., assumes the outlet becomes clogged during a storm event). 

3.2.1 Ash Pond #3 – Hydrologic and Hydraulic Design 

CHA reviewed hydrologic and hydraulic analyses performed by GAI Consultants in 1999 when 

the spillway was repaired. These analyses suggest that 50 percent of the PMP at the R Paul 

Smith site is 14 inches, and the drainage area is about 64 acres. When accounting for infiltration 

within the watershed, the resulting volume of inflow to Ash Pond #3 was determined by GAI to 
 -47- Final Report 

Assessment of Dam Safety of 

Coal Combustion Surface Impoundments 

 Allegheny Energy 

R. Paul Smith Station 

Williamsport, Maryland & 

Falling Waters, West Virginia 

be 37.4 acre-feet. From a maximum operating pool of El. 373, the resulting peak water surface 

elevation is 377.5. 

3.2.2 Ash Pond #4 – Hydrologic and Hydraulic Design 

CHA reviewed hydrologic and hydraulic analyses performed by SE Technologies, Inc. in 1997 

when the spillway was repaired. These analyses used 50 percent of the PMP reported to be 

13.75 inches, and a drainage area of about 74 acres. The maximum reported elevation in Ash 

Pond #4 was determined to be El. 372.9 with discharge through the spillway. The outflow 

hydrograph ordinates were included in the report, so CHA evaluated the volume which this 

analysis assumed would discharge from the pond and determined that during the storm event, 

approximately 6.1 acre-feet had been estimated to drain from the pond. From the elevationvolume rating curve included in the SE Technologies report, CHA determined that even without 

outflow from the outlet structure, the design storm will be stored within the pond. With outflow 

the peak water surface elevation will be about El. 372.9, and without outflow the peak water 

surface elevation will be slightly below El. 375 with the top of the dikes at El. 378. 

3.2.3 Flooding from the Potomac River 

The Potomac River is susceptible to flooding. The highest recorded flooding occurred in 1936 

when the River rose to El. 377.6 at the ash ponds. In 1972, runoff from Hurricane Agnes 

reportedly resulted in peak river flows in the area of Ash Ponds #3 and #4 of approximately El. 

365. Having been inactive for several years, prior to return to service,in 1980, the rock buttress 

was added to the Pond #3 east dike and the crest of the dikes were raised to El. 380. The crest of 

Pond #4 is at El. 378. 
 -48- Final Report 

Assessment of Dam Safety of 

Coal Combustion Surface Impoundments 

 Allegheny Energy 

R. Paul Smith Station 

Williamsport, Maryland & 

Falling Waters, West Virginia 

CHA reviewed data readily available on the internet on historic flooding in the Potomac River at 

Williamsport, Maryland and Falling Waters, West Virginia. Available references from USGS 

and FEMA indicate: 

• 100-yr flood elevation is estimated on FIRM maps to be El. 371 adjacent to the upstream 

end of Pond #4 and at El. 372 at the power plant dam, slightly upstream from the 

upstream end of Pond #3. 

• Top five historic crests on Potomac between 1936 and present do not include Hurricane 

Agnes in 1972. These five events ranged from crest stage 34.8 to 48.6. Flood stage is 

reportedly at 23 feet (or approximately El. 329 based on the peak stage and elevation 

associated with the 1936 event). No specific correlation between River stage and 

elevation was found for this section of the Potomac River. 

• Top five historic crests reported in Williamsport were also listed as the top five in 

Hancock the nearest upstream USGS gauging station. Four of the top five in 

Williamsport were in the top five at Shepherdstown, the nearest downstream USGS 

gauging station. Data available suggested that it was possible that during a 1996 event 

the gage in Shepherdstown was not in service. At Shepherdstown a 1985 event had about 

the same river stage level as Hurricane Agnes; the 1985 event at Hancock was about 5 

feet lower than the rise at Hancock as a result of Hurricane Agnes. 

Hurricane Agnes dropped 6.3 inches of rain on Hagerstown, Maryland (about 6 miles to the 

northeast from Williamsport) between June 20 and 23, 1972. Reportedly, despite the rain, flood 

levels on the Potomac did not come close to the record floods of 1936, which resulted from a 

combination of heavy rain on top of heavy snow packs. A similar rain on snow event occurred 

in 1996, which produced one of the top five flood events in this area of the Potomac River. 

Reports about the impact of Hurricane Agnes indicated that above Hancock, no unusual flooding 

was observed and that most of the flooding occurred in tributaries of the Potomac River 
 -49- Final Report 

Assessment of Dam Safety of 

Coal Combustion Surface Impoundments 

 Allegheny Energy 

R. Paul Smith Station 

Williamsport, Maryland & 

Falling Waters, West Virginia 

downstream of the confluence with the Shenandoah River. On tributaries between the 

Conococheague Creek at Fairview, Maryland, which joins the Potomac River in Williamsport, 

and the Rock Creek at Washington, DC, flooding exceeded the 100-year frequency elevations. 

Peak flows in some of the larger streams ranged from 2 to 6 times greater than previously 

recorded maximums. 

Given the relatively frequent number of flooding events between 1936 and the present at 

Williamsport, CHA recommends quantifying the risk to Ash Ponds #3 and #4 from high waters 

on the Potomac River. 

3.3 Structural Adequacy & Stability 

CHA has reviewed engineering reports for slope stability in comparison to the criteria 

established by West Virginia Rule 47CSR34 for Ash Ponds #3 and #4 as indicated in the 

following subsections. 

3.3.1 Ash Pond #3 – Structural Adequacy & Stability 

GAI reviewed the structural stability of Ash Pond #3 as part of Allegheny Energy’s response to 

WVDEP’s Order of Compliance following the TVA Kingston incident. This review was largely 

performed by reviewing previous engineering reports by GAI and others dating back to 1978. 

The analyses were performed looking at downstream slopes of 2H:1V, and “as designed” 

upstream slopes of 3H:1V. The upstream slope was much steeper below the maximum ash 

disposal line during CHA’s site visit due to over excavation during 2008 dredging operations, 

and this type of condition was described by GAI as being noted in 1978 and 1995 as well. 

The general soil profile at Ash Pond #3 consists of the homogeneous silty clay fill embankment 

founded on natural silty clay overlying sand and gravel overlying bedrock. Table 2 summarizes 
 -50- Final Report 

Assessment of Dam Safety of 

Coal Combustion Surface Impoundments 

 Allegheny Energy 

R. Paul Smith Station 

Williamsport, Maryland & 

Falling Waters, West Virginia 

the soil properties used in the stability analyses. The year in parentheses indicates properties 

used in the respective reviews of stability. 

Table 2 – Ash Pond #3 Soil Parameters Used in Stability Analyses 

Soil Stratum Unit Weight 

(pcf) 

Friction Angle 

(degrees) 

Cohesion 

(psf) 

Embankment Fill 130 (‘95) 

125 (‘99) 

32 (’95) 

28 (’99) 

100 (’95) 

200 (’99) 

Ash 95 (’95,’99) 31 (’95,’99) 0 (’95,’99) 

Proposed Shale Fill 125 (’99) 34 (’99) 400 (’99) 

Rip Rap 140 (’95,’99) 40 (’95,’99) 0 (’95,’99) 

Natural Silty Clay 130 (’95) 

125 (‘99) 35 (’95,’99) 0 (’95,’99) 

Natural Sand and Gravel1 135 (’95) 39 (’95) 0 (’95) 

1. Sand and gravel layer not included in 1999 analyses 

Cross sections of the north, south and buttressed east dikes were evaluated for stability. The 

results of these analyses are presented in Table 3 below and graphical interpretation is presented 

in Figures 4B (Section 2), 7A and 7B. 

Table 3 – Ash Pond #3 Engineering Comparison to Design Criteria 

Design Consideration Criteria Engineering Results 

North Dike East Dike South Dike 

Downstream Slope Steady State 

Conditions (1995): 

Pond surface @ El. 378 

Potomac River @ Normal Pool 

1.5 SS1

1.2 EQ2

1.8 SS 

1.5 EQ 

1.5 SS 

1.3 EQ 

2.0 SS 

1.7 EQ 

Downstream Slope Steady State 

Conditions (1995): 

Pond surface @ El. 378 

Potomac River @ El. 376

-- 1.9 SS 

1.5 EQ 

1.9 SS 

1.5 EQ 

2.0 SS 

1.5 EQ 
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Assessment of Dam Safety of 

Coal Combustion Surface Impoundments 

 Allegheny Energy 

R. Paul Smith Station 

Williamsport, Maryland & 

Falling Waters, West Virginia 

Table 3 – Ash Pond #3 Engineering Comparison to Design Criteria - continued 

Design Consideration Criteria Engineering Results 

North Dike East Dike South Dike 

Upstream Slope Steady State 

Conditions (1999): 

Pond surface @El. 372 

Potomac River @ Normal Pool

1.5 2.2 2.2 2.2 

Upstream Slope Steady State 

Conditions (1995): 

Pond surface @ El. 360 

Potomac River @El. 376

-- 1.5 SS 

1.3 EQ 

1.5 SS 

1.3 EQ 

1.5 SS 

1.3 EQ 

Upstream Slope Steady State 

Conditions (1999): 

Pond surface @ El. 360 

Potomac River @El. 376

-- 1.6 1.6 1.6 

Upstream Slope Rapid Drawdown 

Conditions (1999): 

Pond drawdown to El. 360 

(Approx. discharge pipe elev.) 

Pond drawdown to El. 347 

1.2 1.4 

1.1 

1.4 

1.1 

1.4 

1.1 

Analyze liquefaction potential and safeguard 

against if needed 

No conclusion provided to CHA. 

1. SS = Steady State loading conditions 

2. EQ = Earthquake loading conditions 

The upstream slope stability analyses performed in 1999 indicate that the upstream slopes would 

be regraded with shale fill to return the slopes to a 3H:1V slope angle following over excavation 

during dredging operations. CHA did not observe shale fill along slopes still apparently at 

approximate 3H:1V slopes although deposited ash from successive years of pond use may have 

buried this fill. However, the northeast corner of the impoundment was severely over excavated 

during 2008 dredging operations resulting in an upstream slope between 1.6H:1V to steeper than 

1:1 based on a May 2009 survey and field observations by CHA. Based on the May 2009 

survey, slopes not over excavated during the last dredging operation were between 2.5H:1V and 

3H:1V. 
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Assessment of Dam Safety of 

Coal Combustion Surface Impoundments 

 Allegheny Energy 

R. Paul Smith Station 

Williamsport, Maryland & 

Falling Waters, West Virginia 

An evaluation of liquefaction was not provided to CHA. However, subsurface information 

provided does not appear to suggest liquefaction susceptible foundation soils are found at this 

site. 

3.3.2 Ash Pond #4 – Structural Adequacy & Stability 

GAI reviewed the structural stability of Ash Pond #4 as part of Allegheny Energy’s response to 

WVDEP’s Order of Compliance following the TVA Kingston incident. To evaluate the stability 

of the Ash Pond #4 dikes, GAI began by reviewing past reports by SRW in 1980 and SE 

Technologies in 1997. From soil borings performed by SRW in 1980, the strata and associated 

engineering properties were identified at the site as shown in Table 4. 

Table 4 – Ash Pond #4 Soil Parameters Used in Stability Analyses 

Soil Stratum Unit Weight 

(pcf) 

Friction Angle 

(degrees) 

Cohesion 

(psf) 

Shale Fill 135 38 0 

Clay (Embankment Fill) 135 35 0 

Soft to Medium Stiff Clay, 

some silt and sand 130 32 0 

Medium Stiff to Stiff Clay, 

some silt and sand 135 35 0 

Medium Stiff to Very Stiff 

Clay and Silt, some sand 135 31 0 

Stiff to Very Stiff Clay and 

Silt, some sand 135 35 0 

Sand and Gravel 140 38 0 

Fly Ash 75 30 0 

Note: not all strata were represented in each cross section analyzed. 

GAI reproduced cross sections of the Ash Pond #4 dikes based on strata boundaries and soil 

propertied from the SRW cross section with the exception of including a friction angle of 30 

degrees for the fly ash, whereas SRW did not assume strength within the fly ash and a peak 
 -53- Final Report 

Assessment of Dam Safety of 

Coal Combustion Surface Impoundments 

 Allegheny Energy 

R. Paul Smith Station 

Williamsport, Maryland & 

Falling Waters, West Virginia 

ground acceleration of 0.08g was used as compared to SRW 0.05g. Cross sections of the north, 

east, and south dikes were evaluated for stability. The results of these analyses are presented in 

Table 5 below and graphical representation is presented in Figures 8A through 8H. The 

proposed bench listed in the table is a proposed modification by GAI to meet upstream slope 

required factors of safety. The bench is proposed to be “left in place” fly ash. This bench will be 

created each time the pond is dredged through a modification to the cleanout procedures and 

field survey indicating the limits of dredging to occur. 

Table 5 – Ash Pond #4 Engineering Comparison to Design Criteria 

Design Consideration Criteria North Dike East Dike South Dike 

Steady State Normal Pool 1.5 1.5 1.5 1.5 

Earthquake and 

Normal Pool 

1.2 1.3 1.2 1.2 

Upstream Steady State 

Normal Pool with 

Proposed Bench 

1.5 2.2 (deep) 

1.4 (shallow) 2.6 (deep) 

1.5 (shallow) Not Performed 

Upstream Earthquake 

Normal Pool with 

Proposed Bench 

1.2 1.6 (deep) 

1.2 (shallow) 

1.8 (deep) 

1.2 (shallow) Not Performed 

Upstream Slope Rapid 

Drawdown with 

Proposed Bench 

1.2 2.4 2.4 Not Performed 

3.3.3 Instrumentation Review Relative to Stability 

There are inactive piezometers on the Ash Pond #4 dikes that were installed in 1997. GAI found 

several of these piezometers and found water levels to be 30 or more feet below the dam crest, 

which is consistent with the hypalon liner effectively preventing seepage through the 

embankment. 

There are no monitoring instruments on the Ash Pond #3 dikes. 
 -54- Final Report 

Assessment of Dam Safety of 

Coal Combustion Surface Impoundments 

 Allegheny Energy 

R. Paul Smith Station 

Williamsport, Maryland & 

Falling Waters, West Virginia 

3.4 Operations, Maintenance, and Inspections 

West Virginia Rule 47CSR34 15.4 requires periodic safety inspections of dams as follows for 

Class 2, significant hazard dams: 

• Monthly or more frequently by the Owner; 

• At least every three years by the Owner’s engineer; and 

• At any time as desired by the State. 

According to our conversations with WVDEP, these inspections are only required to be visual 

inspections. Inspection reports for those inspections performed by the Owner’s engineer are to 

be submitted to WVDEP and are to include descriptions of maintenance work to be performed as 

a result of the inspection findings. These reports are to be certified by an engineer to verify that 

the dam and its appurtenances are functioning as designed. Special inspections are required 

following a storm event equal to or greater than a 50-year, 6 hour rainfall following the same 

reporting criteria, which at Ash Ponds #3 and #4 is about 4.5 inches according to National 

Weather Service’s Technical Paper No. 40 - Rainfall Frequency Atlas of the Eastern United 

States for Duration from 30 minutes to 24 hours and Return Periods from 1 to 100 years (TP40). 

3.4.1 Inspection Procedures 

Allegheny Energy hires an outside consultant to inspect the dams every two years. CHA was 

provided with copies of inspection reports for 2004, 2006, 2008 and 2009. Although earlier than 

usual, an additional inspection was performed in 2009 as a proactive measure following the TVA 

Kingston incident. These inspections are typically performed following vegetation clearing in 

the spring. These inspection reports are submitted to WVDEP. 
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Assessment of Dam Safety of 

Coal Combustion Surface Impoundments 

 Allegheny Energy 

R. Paul Smith Station 

Williamsport, Maryland & 

Falling Waters, West Virginia 

Typical items of note during these inspections included small saplings taking root on the 

embankments, animal burrows, over excavation of upstream slopes during dredging, small holes 

in the hypalon liner at Ash Pond #4, sparse vegetation in some areas, minor surface sloughing 

from runoff. 

3.4.2 Inspections by West Virginia Dam Safety 

WVDEP dam safety personnel make periodic inspections of Ash Ponds #3 and #4. Over the last 

five years, West Virginia Dam Safety personnel have made inspections in 2009, and 2006. The 

most recent inspection in 2009 was performed in follow-up to the TVA incident, and was part of 

a West Virginia Dam Safety initiative to have current site visits to each of the coal waste 

impoundments at power plants in the State. 

Typical items of note during these inspections included removing animals and filling burrows, 

repair holes in the upstream liner at Ash Pond #4, monitor movement of the downstream slope 

where fence post foundations are exposed from surficial sloughing, and over excavation during 

dredging of the upstream slopes. 

Brian Long, PE (WVDEP) indicated to CHA that the recommendations are of maintenance needs 

only. They do not use the inspection report as a medium for transmitting more serious concerns 

or needs at the dam. More serious issues, not addressed in a timely manner by the Owner on 

their own accord would be addressed via the Civil Administrative Penalties section of 47CSR34. 

3.4.3 Maintenance 

Allegheny Energy provided CHA with a copy of their Dam Safety Maintenance Plans for Ash 

Ponds #3 and #4 which were approved by WVDEP in May 2006. These maintenance plans 
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Assessment of Dam Safety of 

Coal Combustion Surface Impoundments 

 Allegheny Energy 

R. Paul Smith Station 

Williamsport, Maryland & 

Falling Waters, West Virginia 

provide a matrix of maintenance activities and the month in which these maintenance tasks are to 

be performed. The maintenance matrices are attached at the end of this section. 

3.5 Foundation Conditions 

Data reviewed by CHA indicates that Ash Ponds #3 and #4 were constructed on natural clay, silt 

and sand alluvial deposits. Constructed in the 1960s, no foundation preparation plans were 

available for CHA’s review. 










 -67- Final Report 

Assessment of Dam Safety of 

Coal Combustion Surface Impoundments 

 Allegheny Energy 

R. Paul Smith Station 

Williamsport, Maryland & 

Falling Waters, West Virginia 

4.0 CONCLUSIONS/RECOMMENDATIONS 

4.1 Acknowledgement of Management Unit Condition 

I acknowledge that the management unit referenced herein was personally inspected by me and 

was found to be in the following condition: Satisfactory. 

A management unit found to be in satisfactory condition is defined as one in which no existing 

or potential management unit safety deficiencies are recognized. Acceptable performance is 

expected under all applicable loading conditions in accordance with the applicable criteria. 

Minor maintenance items may be required. 

CHA presents the following recommendations for maintenance and updating of analyses in 

Sections 4.2 through 4.6. 

4.2 Upstream Slopes 

In reviewing historic documents for Ash Ponds #3 and #4, there were several mentions of 

portions of the upstream slopes of the dikes being over excavated during pond dredging 

operations. CHA observed this type of situation on the north end of the Ash Pond #3 dike. 

Proposed improvements to the Ash Pond #4 upstream slopes include leaving a buttress of 

deposited fly ash in place after each dredging. Careful survey control and monitoring of 

contractor activities is needed to ensure that dredging operations do not alter the slope angles 

needed to meet the required factors of safety with regard to slope stability. 

In addition, before Ash Pond #3 is put back into service, the upstream slope in the northeast 

corner of the pond should be repaired with compacted soil having similar characteristics to the 

design properties of the dam and placed to the designed slope angle. 
 -68- Final Report 

Assessment of Dam Safety of 

Coal Combustion Surface Impoundments 

 Allegheny Energy 

R. Paul Smith Station 

Williamsport, Maryland & 

Falling Waters, West Virginia 

4.3 Downstream Slopes on Ash Pond #4 

Surface soils were quite soft on the downstream slope of Ash Pond #4 and were subject to 

sloughing underfoot while walking on the slopes. Irregularity in the slope surface and review of 

previous reports suggested that surface sloughing is an ongoing situation on the Ash Pond #4 

dikes. In addition to general softness and grading irregularities, CHA observed erosion rills, and 

possible bulge areas as discussed in Section 2.3.1. CHA recommends quantitative monitoring of 

the downstream slope surfaces to provide better information regarding the nature of slope 

movements and changes. 

Continued removal of brush and small shrubs is required. Trees between Ash Pond #4 and the 

Potomac River for the most part start just beyond the toe of the east dike. However, in a few 

locations, there are large trees within the toe of the dike. CHA recommends at least a 10-foot 

buffer zone between the toe of the dike and tree growth. 

Some of the trees from beyond the toe of the east dike have branches nearing contact with upper 

portions of the slope. CHA recommends these branches be cut to facilitate access on the slope, 

and to prevent branches from rooting on the slope of the dike. 

4.4 Tree Removal on Ash Pond #3 Buttress 

The stone fill buttress on the east dike of Ash Pond #3 is heavily covered in trees. Trees on 

embankments can compromise the integrity of the slope by creating scarps if trees fall over from 

age or during a storm, and roots penetrating into the embankment can provide preferential paths 

for seepage. In addition, these trees make inspection of the toe of the buttress difficult. 

Therefore, CHA recommends the trees along the buttress be removed. 
 -69- Final Report 

Assessment of Dam Safety of 

Coal Combustion Surface Impoundments 

 Allegheny Energy 

R. Paul Smith Station 

Williamsport, Maryland & 

Falling Waters, West Virginia 

4.5 Monitoring Instrumentation 

CHA recommends piezometers be installed on the Ash Pond #3 dikes to evaluate the phreatic 

surface with relation to the phreatic surfaced assumed for the stability analyses. Routine 

monitoring of the phreatic surface should be established with corresponding elevations of the 

water and ash levels within the pond at the time of measurement for a comprehensive 

understanding of the embankment behavior. 

4.6 Evaluation of Conditions from Potomac River Flooding 

 CHA understands that the Ash Pond #3 dikes were raised in 1980 to be 3.4 feet higher than the 

water surface elevation attained by the Potomac River at Williamsport during Hurricane Agnes 

in 1972. A brief review of historical flood records suggests that Hurricane Agnes has crested in 

the vicinity of Williamsport higher than the flows from Hurricane Agnes at least five times since 

1936. CHA recommends that a comprehensive, probabilistic analysis of flood elevations in the 

Potomac River at Williamsport be performed. This analysis should include estimated river 

velocities at the stream banks to evaluate the adequacy of the rip rap protection on Ash Pond #3 

and whether bank armoring is needed on Ash Pond #4. 
 -70- Final Report 

Assessment of Dam Safety of 

Coal Combustion Surface Impoundments 

 Allegheny Energy 

R. Paul Smith Station 

Williamsport, Maryland & 

Falling Waters, West Virginia 

5.0 CLOSING 

 

The information presented in this report is based on visual field observations, review of reports 

by others and this limited knowledge of the history of the R. Paul Smith Station surface 

impoundments. The recommendations presented are based, in part, on project information 

available at the time of this report. No other warranty, expressed or implied is made. Should 

additional information or changes in field conditions occur, the conclusions and 

recommendations provided in this report should be re-evaluated by an experienced engineer. 
 Final Report 

Assessment of Dam Safety of 

Coal Combustion Surface Impoundments 

 Allegheny Energy 

R. Paul Smith Station 

Williamsport, Maryland & 

Falling Waters, West Virginia 

APPENDIX A 

Completed EPA Coal Combustion Dam Inspection Checklist Forms 

& 

Completed EPA Coal Combustion Waste (CCW) Impoundment Inspection Forms

 
Site Name: Date:

Unit Name: Operator's Name: 

Unit I.D.: Hazard Potential Classification: High Significant Low

Inspector's Name: 

Coal Combustion Dam Inspection Checklist Form

US Environmental

Protection Agency

Check the appropriate box below. Provide comments when appropriate. If not applicable or not available, record "N/A". Any unusual conditions or 

construction practices that should be noted in the comments section. For large diked embankments, separate checklists may be used for different 

embankment areas. If separate forms are used, identify approximate area that the form applies to in comments.

Yes No Yes No

1. Frequency of Company's Dam Inspections? 18. Sloughing or bulging on slopes? 

2. Pool elevation (operator records)? 19. Major erosion or slope deterioration?

3. Decant inlet elevation (operator records)? 20. Decant Pipes: 

4. Open channel spillway elevation (operator records)? Is water entering inlet, but not exiting outlet? 

5. Lowest dam crest elevation (operator records)? Is water exiting outlet, but not entering inlet? 

6. If instrumentation is present, are readings 

 recorded (operator records)? Is water exiting outlet flowing clear?

7. Is the embankment currently under construction? 21. Seepage (specify location, if seepage carries fines, 

and approximate seepage rate below):

8. Foundation preparation (remove vegetation,stumps, 

topsoil in area where embankment fill will be placed)? From underdrain?

9. Trees growing on embankment? (If so, indicate

 largest diameter below) At isolated points on embankment slopes? 

10. Cracks or scarps on crest? At natural hillside in the embankment area? 

11. Is there significant settlement along the crest? Over widespread areas? 

12. Are decant trashracks clear and in place? From downstream foundation area?

13. Depressions or sinkholes in tailings surface or

whirlpool in the pool area? "Boils" beneath stream or ponded water?

14. Clogged spillways, groin or diversion ditches? Around the outside of the decant pipe? 

15. Are spillway or ditch linings deteriorated? 22. Surface movements in valley bottom or on hillside?

16. Are outlets of decant or underdrains blocked? 23. Water against downstream toe?

17. Cracks or scarps on slopes? 24. Were Photos taken during the dam inspection? 

Major adverse changes in these items could cause instability and should be reported for

further evaluation. Adverse conditions noted in these items should normally be described (extent, location, 

volume, etc.) in the space below and on the back of this sheet. 

Inspection Issue # Comments

EPA FORM -XXXX

R. Paul Smith Power Station 10-20-09

Ash Pond #3 Allegheny Energy

Ash Pond #3

Annually

Katherine Adnams & Khalid Abed, P.E.

See Note

368

NA See Note 2

379.4

NA

X

X

X

X

NA

NA NA

See Note

X

X

X

X

X

X

X

X

X

X

X

 X

X

X

X

X

X

X

N/A = Not Applicable/Available

Pond #3 is currently in the dredged state and is not in operation. Remaining water is below the lowest decant elevation. Pond #3

will return to service when Pond #4 is full. Highest decant elevation at 368.0

Trees were noted on the stone buttress not the original dike slope.

Routine maintenance item for Allegheny Energy includes clearing debris deposited at discharge channel/Potomac River confluence.

Debris gets deposited during recession of high flows on the Potomac River.

2.

14.

21. A seepage area is monitored to the south of Ash Basin #3. No flow was observed in standing water. Allegheny Energy believes the

9.

wet area is related to stormwater drainage from hillside through adjacent wetland, but continue to monitor. No fines observed.

23. The toe of the stone buttress is approximately at the waters edge of the Potomac River. Flooding on the Potomac will rise against the dike.
U. S. Environmental Protection Agency

Coal Combustion Waste (CCW)

Impoundment Inspection

Impoundment NPDES Permit # _____________________ INSPECTOR______________________

Date ____________________________________

Impoundment Name ________________________________________________________

Impoundment Company ____________________________________________________

EPA Region ___________________

State Agency (Field Office) Addresss __________________________________________

__________________________________________

Name of Impoundment _____________________________________________________

(Report each impoundment on a separate form under the same Impoundment NPDES

 Permit number)

New ________ Update _________

 Yes No

Is impoundment currently under construction? ______ ______

Is water or ccw currently being pumped into 

the impoundment? ______ ______

IMPOUNDMENT FUNCTION: _____________________________________________

Nearest Downstream Town : Name ____________________________________

Distance from the impoundment __________________________ 

Impoundment

Location: Longitude ______ Degrees ______ Minutes ______ Seconds 

 Latitude ______ Degrees ______ Minutes ______ Seconds 

State _________ County ___________________________ 

Does a state agency regulate this impoundment? YES ______ NO ______ 

If So Which State Agency?___________________________________________

EPA Form XXXX-XXX, Jan 09 1

MD0000582 Adnams/Abed

October 20, 2009

Ash Pond #3

Allegheny Energy

3

1800 Washington Boulevard

Baltimore, MD 21230

Ash Pond #3

X

X

X

Receives all CCW related waste water from the plant. Alternates use with

Ash Pond #4

Falling Water, WV

Approx. 4.5 miles

77 49 51

39 35 51

WV Berkeley

X

MD Department of the Environment - NPDES

WV Department of Environmental Protection - Dam Safety
HAZARD POTENTIAL (In the event the impoundment should fail, the 

following would occur): 

______ LESS THAN LOW HAZARD POTENTIAL: Failure or misoperation of 

the dam results in no probable loss of human life or economic or environmental 

losses.

______ LOW HAZARD POTENTIAL: Dams assigned the low hazard potential 

classification are those where failure or misoperation results in no probable loss of 

human life and low economic and/or environmental losses. Losses are principally 

limited to the owner’s property. 

______ SIGNIFICANT HAZARD POTENTIAL: Dams assigned the significant 

hazard potential classification are those dams where failure or misoperation results 

in no probable loss of human life but can cause economic loss, environmental 

damage, disruption of lifeline facilities, or can impact other concerns. Significant 

hazard potential classification dams are often located in predominantly rural or 

agricultural areas but could be located in areas with population and significant 

infrastructure.

______ HIGH HAZARD POTENTIAL: Dams assigned the high hazard 

potential classification are those where failure or misoperation will probably cause 

loss of human life. 

DESCRIBE REASONING FOR HAZARD RATING CHOSEN: 

_________________________________________________________________

_________________________________________________________________

_________________________________________________________________

_________________________________________________________________

_________________________________________________________________

_________________________________________________________________

_________________________________________________________________

_________________________________________________________________

_________________________________________________________________

_________________________________________________________________

_________________________________________________________________

_________________________________________________________________

_________________________________________________________________

_________________________________________________________________

_________________________________________________________________

EPA Form XXXX-XXX, Jan 09 2

X

Relatively small impoundments compared to volume of the Potomac River and elevation of

riverfront homes suggest loss of life is not a concern. However, environmental impacts to the

Potomac River if a breach were to occur would cause environmental damage.
CONFIGURATION:

Height original 

ground 

CROSS-VALLEY

Height original 

ground 

SIDE-HILL

Water or ccw

DIKED

original ground Height 

Height original 

ground 

CROSS-VALLEY

Water or ccw

original 

ground 

SIDE-HILL

Height original 

ground 

CROSS-VALLEY

original 

ground 

SIDE-HILL

Height original 

ground 

SIDE-HILL

 Water or ccw

INCISED

Water or ccw

original 

ground 

_____ Cross-Valley 

_____ Side-Hill 

_____ Diked 

_____ Incised (form completion optional)

_____ Combination Incised/Diked 

Embankment Height __________ feet Embankment Material_______________

Pool Area __________________ acres Liner ____________________________ 

Current Freeboard ___________ feet Liner Permeability _________________

EPA Form XXXX-XXX, Jan 09 3

X

46 Homogeneous compacted fill

~6 at maximum decant None

 14 at max. decant NA
TYPE OF OUTLET (Mark all that apply)

TRAPEZOIDAL

Avg 

Depth 

Bottom 

Width 

Depth 

TRIANGULAR _____ Open Channel Spillway

_____ Trapezoidal Top Width Top Width 

_____ Triangular 

RECTANGULAR IRREGULAR

Depth _____ Rectangular 

_____ Irregular 

_____ depth 

_____ bottom (or average) width 

Width 

Depth 

Average Width 

_____ top width 

_____ Outlet

_____ inside diameter 

Material Inside Diameter 

_____ corrugated metal 

_____ welded steel 

_____ concrete 

_____ plastic (hdpe, pvc, etc.) 

_____ other (specify) ____________________ 

Is water flowing through the outlet? YES _______ NO _______ 

_____ No Outlet 

_____ Other Type of Outlet (specify) ________________________________

The Impoundment was Designed By ____________________________________

__________________________________________________________________

EPA Form XXXX-XXX, Jan 09 4

X

14-in.

X HDPE Sliplined CMP

X

Unknown
Has there ever been a failure at this site? YES __________ NO ___________ 

If So When? ___________________________ 

If So Please Describe : _____________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

EPA Form XXXX-XXX, Jan 09 5

X

 December 1998

In December 1998 a breach of the outlet pipe occurred. According to Allegheny Energy no release of

impounded material occurred. This failure occured after a decant structure/outlet slip lining project had been

performed at Pond #4 in 1997 under maintenance operations.
Has there ever been significant seepages at this site? YES _______ NO _______

If So When? ___________________________ 

IF So Please Describe: _______________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

EPA Form XXXX-XXX, Jan 09 6

X
Has there ever been any measures undertaken to monitor/lower

Phreatic water table levels based on past seepages or breaches 

at this site? YES ________NO ________ 

If so, which method (e.g., piezometers, gw pumping,...)? ____________________

If so Please Describe : ____________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

EPA Form XXXX-XXX, Jan 09 7

X
Site Name: Date:

Unit Name: Operator's Name: 

Unit I.D.: Hazard Potential Classification: High Significant Low

Inspector's Name: 

Coal Combustion Dam Inspection Checklist Form

US Environmental

Protection Agency

Check the appropriate box below. Provide comments when appropriate. If not applicable or not available, record "N/A". Any unusual conditions or 

construction practices that should be noted in the comments section. For large diked embankments, separate checklists may be used for different 

embankment areas. If separate forms are used, identify approximate area that the form applies to in comments.

Yes No Yes No

1. Frequency of Company's Dam Inspections? 18. Sloughing or bulging on slopes? 

2. Pool elevation (operator records)? 19. Major erosion or slope deterioration?

3. Decant inlet elevation (operator records)? 20. Decant Pipes: 

4. Open channel spillway elevation (operator records)? Is water entering inlet, but not exiting outlet? 

5. Lowest dam crest elevation (operator records)? Is water exiting outlet, but not entering inlet? 

6. If instrumentation is present, are readings 

 recorded (operator records)? Is water exiting outlet flowing clear?

7. Is the embankment currently under construction? 21. Seepage (specify location, if seepage carries fines, 

and approximate seepage rate below):

8. Foundation preparation (remove vegetation,stumps, 

topsoil in area where embankment fill will be placed)? From underdrain?

9. Trees growing on embankment? (If so, indicate

 largest diameter below) At isolated points on embankment slopes? 

10. Cracks or scarps on crest? At natural hillside in the embankment area? 

11. Is there significant settlement along the crest? Over widespread areas? 

12. Are decant trashracks clear and in place? From downstream foundation area?

13. Depressions or sinkholes in tailings surface or

whirlpool in the pool area? "Boils" beneath stream or ponded water?

14. Clogged spillways, groin or diversion ditches? Around the outside of the decant pipe? 

15. Are spillway or ditch linings deteriorated? 22. Surface movements in valley bottom or on hillside?

16. Are outlets of decant or underdrains blocked? 23. Water against downstream toe?

17. Cracks or scarps on slopes? 24. Were Photos taken during the dam inspection? 

Major adverse changes in these items could cause instability and should be reported for

further evaluation. Adverse conditions noted in these items should normally be described (extent, location, 

volume, etc.) in the space below and on the back of this sheet. 

Inspection Issue # Comments

EPA FORM -XXXX

R. Paul Smith Power Station 10-20-09

Ash Pond #4 Allegheny Energy

Ash Pond #4

Biennially

Katherine Adnams & Khalid Abed, P.E.

X

367.7

367.7

NA

378

X

X

X

X

X

NA NA

X

X

X

X

X

X

X

X

X

X

X

 X

X

X

X

X

X

X

X

N/A = Not Applicable/Available.

Occasional small shrubs were noted on the south dike.

Surface soils on dike slopes are soft and prone to erosion. No serious areas of concern were noted.

.Small surface sloughs occur when walking on particularly soft surface soils. A few areas of possible bulges were noted, but were

reported by Allegheny Energy to be observed during routine inspections and changes had not been observed in many years.

9.

18.

19.
U. S. Environmental Protection Agency

Coal Combustion Waste (CCW)

Impoundment Inspection

Impoundment NPDES Permit # _____________________ INSPECTOR______________________

Date ____________________________________

Impoundment Name ________________________________________________________

Impoundment Company ____________________________________________________

EPA Region ___________________

State Agency (Field Office) Addresss __________________________________________

__________________________________________

Name of Impoundment _____________________________________________________

(Report each impoundment on a separate form under the same Impoundment NPDES

 Permit number)

New ________ Update _________

 Yes No

Is impoundment currently under construction? ______ ______

Is water or ccw currently being pumped into 

the impoundment? ______ ______

IMPOUNDMENT FUNCTION: _____________________________________________

Nearest Downstream Town : Name ____________________________________

Distance from the impoundment __________________________ 

Impoundment

Location: Longitude ______ Degrees ______ Minutes ______ Seconds 

 Latitude ______ Degrees ______ Minutes ______ Seconds 

State _________ County ___________________________ 

Does a state agency regulate this impoundment? YES ______ NO ______ 

If So Which State Agency?___________________________________________

EPA Form XXXX-XXX, Jan 09 1

MD0000582 Adnams/Abed

October 20, 2009

Ash Pond #4

Allegheny Energy

3

1800 Washington Boulevard

Baltimore, MD 21230

Ash Pond #4

X

X

X

Receives all CCW related waste water from the plant. Alternates use with

Ash Pond #3

Falling Water, WV

Approx. 4.5 miles

77 49 51

39 35 51

WV Berkeley

X

MD Department of the Environment - NPDES

WV Department of Environmental Protection - Dam Safety
HAZARD POTENTIAL (In the event the impoundment should fail, the 

following would occur): 

______ LESS THAN LOW HAZARD POTENTIAL: Failure or misoperation of 

the dam results in no probable loss of human life or economic or environmental 

losses.

______ LOW HAZARD POTENTIAL: Dams assigned the low hazard potential 

classification are those where failure or misoperation results in no probable loss of 

human life and low economic and/or environmental losses. Losses are principally 

limited to the owner’s property. 

______ SIGNIFICANT HAZARD POTENTIAL: Dams assigned the significant 

hazard potential classification are those dams where failure or misoperation results 

in no probable loss of human life but can cause economic loss, environmental 

damage, disruption of lifeline facilities, or can impact other concerns. Significant 

hazard potential classification dams are often located in predominantly rural or 

agricultural areas but could be located in areas with population and significant 

infrastructure.

______ HIGH HAZARD POTENTIAL: Dams assigned the high hazard 

potential classification are those where failure or misoperation will probably cause 

loss of human life. 

DESCRIBE REASONING FOR HAZARD RATING CHOSEN: 

_________________________________________________________________

_________________________________________________________________

_________________________________________________________________

_________________________________________________________________

_________________________________________________________________

_________________________________________________________________

_________________________________________________________________

_________________________________________________________________

_________________________________________________________________

_________________________________________________________________

_________________________________________________________________

_________________________________________________________________

_________________________________________________________________

_________________________________________________________________

_________________________________________________________________

EPA Form XXXX-XXX, Jan 09 2

X

Relatively small impoundment compared to volume of the Potomac River and elevation of

riverfront homes suggest loss of life is not a concern. However, environmental impacts to the

Potomac River if a breach were to occur would cause environmental damage.
CONFIGURATION:

Height original 

ground 

CROSS-VALLEY

Height original 

ground 

SIDE-HILL

Water or ccw

DIKED

original ground Height 

Height original 

ground 

CROSS-VALLEY

Water or ccw

original 

ground 

SIDE-HILL

Height original 

ground 

CROSS-VALLEY

original 

ground 

SIDE-HILL

Height original 

ground 

SIDE-HILL

 Water or ccw

INCISED

Water or ccw

original 

ground 

_____ Cross-Valley 

_____ Side-Hill 

_____ Diked 

_____ Incised (form completion optional)

_____ Combination Incised/Diked 

Embankment Height __________ feet Embankment Material_______________

Pool Area __________________ acres Liner ____________________________ 

Current Freeboard ___________ feet Liner Permeability _________________

EPA Form XXXX-XXX, Jan 09 3

X

41 Homogeneous compacted fill

~11 at maximum decant Hypalon

 10 at max. decant impermeable
TYPE OF OUTLET (Mark all that apply)

TRAPEZOIDAL

Avg 

Depth 

Bottom 

Width 

Depth 

TRIANGULAR _____ Open Channel Spillway

_____ Trapezoidal Top Width Top Width 

_____ Triangular 

RECTANGULAR IRREGULAR

Depth _____ Rectangular 

_____ Irregular 

_____ depth 

_____ bottom (or average) width 

Width 

Depth 

Average Width 

_____ top width 

_____ Outlet

_____ inside diameter 

Material Inside Diameter 

_____ corrugated metal 

_____ welded steel 

_____ concrete 

_____ plastic (hdpe, pvc, etc.) 

_____ other (specify) ____________________ 

Is water flowing through the outlet? YES _______ NO _______ 

_____ No Outlet 

_____ Other Type of Outlet (specify) ________________________________

The Impoundment was Designed By ____________________________________

__________________________________________________________________

EPA Form XXXX-XXX, Jan 09 4

X

14-in.

X HDPE Sliplined CMP

X

Unknown
Has there ever been a failure at this site? YES __________ NO ___________ 

If So When? ___________________________ 

If So Please Describe : _____________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

EPA Form XXXX-XXX, Jan 09 5

 X
Has there ever been significant seepages at this site? YES _______ NO _______

If So When? ___________________________ 

IF So Please Describe: _______________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

EPA Form XXXX-XXX, Jan 09 6

A Hypalon liner has been installed. Current employees of Allegheny Energy were

uncertain the exact reasons the liner was installed, but suspect it was to reduce

seepage and/or lower the phreatic water surface through the embankment.

(Unknown)
Has there ever been any measures undertaken to monitor/lower

Phreatic water table levels based on past seepages or breaches 

at this site? YES ________NO ________ 

If so, which method (e.g., piezometers, gw pumping,...)? ____________________

If so Please Describe : ____________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

EPA Form XXXX-XXX, Jan 09 7

 X

A Hypalon liner has been installed. Current employees of Allegheny Energy were uncertain the

exact reasons the liner was installed, but suspect it was to reduce seepage and/or lower the

phreatic water surface through the embankment.