Upload
others
View
5
Download
0
Embed Size (px)
Citation preview
CONCEPT ENGINEERING REPORT: WEST TREATMENT POND Bremo Power Station
Submitted To: Virginia Electric and Power Company 1038 Bremo Road Bremo Bluff, VA 23022 Submitted By: Golder Associates Inc. 2108 W. Laburnum Avenue Suite 200 Richmond, VA 23227
June 2016 1520-347.300
Conc
ept E
ngine
ering
Repo
rt: We
st Tre
atmen
t Pon
d
CER: West Treatment Pond i Project No. 1520-347.300 Bremo Power Station June 2016
Table of Contents 1.0 INTRODUCTION ............................................................................................................................... 1
1.1 Site Description ............................................................................................................................. 1 2.0 WASTEWATER SOURCES .............................................................................................................. 1
2.1 During Closure .............................................................................................................................. 2 2.1.1 Metals Pond Pumped Decant Water ..................................................................................... 2 2.1.2 Metals Pond Contact Stormwater ......................................................................................... 2 2.1.3 Metals Pond Material Dewatering Water .............................................................................. 2 2.1.4 Ash Pond Decant Water ........................................................................................................ 2 2.1.5 Ash Pond Contact Stormwater .............................................................................................. 3 2.1.6 Ash Pond Ash Dewatering Water .......................................................................................... 3 2.1.7 Stormwater Treatment Pond Discharge ................................................................................ 3
2.2 Final Conditions ............................................................................................................................ 3 3.0 WEST TREATMENT POND CONSTRUCTION ............................................................................... 3
3.1 West Treatment Pond Capacity .................................................................................................... 4 3.2 Dam Safety .................................................................................................................................... 4
Drawings Drawing 1 – Site Location Map Drawing 2 – Site Plan Drawing 3 – Process Flow Diagram – During Closure Drawing 4 – Process Flow Diagram – Final Conditions Drawing 5 – West Treatment Pond Modification Plan Drawing 6 – West Treatment Pond Modification Details
CER: West Treatment Pond 1 Project No. 1520-347.300 Bremo Power Station June 2016
1.0 INTRODUCTION This Concept Engineering Report (CER) has been prepared for the proposed West Treatment Pond at
Dominion’s Bremo Power Station (Station), located in Fluvanna County, Virginia. The Station converted
from a coal-fired power plant to a natural gas-fired power plant in 2014. Coal Combustion Residuals (CCR)
from historical coal-fired operations are stored in three impoundments on-site (North Ash Pond, West Ash
Pond, and East Ash Pond). Process water from these ponds and other Station activities has historically
been discharged with contact stormwater to the James River pursuant to the authorization, limits, and
conditions of a Virginia Department of Environmental Quality (DEQ) Virginia Pollutant Discharge Elimination
System (VPDES) Permit (Permit No. VA0004138).
Dominion is preparing to close these three CCR surface impoundments in response to the U.S.
Environmental Protection Agency’s (EPA’s) publication of the Federal Hazardous and Solid Waste
Management System; Disposal of Coal Combustion Residuals from Electric Utilities; Final Rule
(40 CFR 257). During closure activities of these three CCR impoundments, Dominion will also close the
Metals Pond by dewatering and removing accumulated solids. Dominion has prepared this CER to provide
a description of the proposed West Treatment Pond, which is expected to be brought on-line following DEQ
approval of this CER.
1.1 Site Description The Bremo Power Station is owned and operated by Virginia Electric and Power Company (Dominion) in
Fluvanna County, Virginia, at 1038 Bremo Road, just east of Route 15 (James Madison Highway) and north
of the James River. The location of the Station is illustrated on the inset United States Geological Survey
(USGS) topographic map on Drawing 1. A Site Plan is presented on an aerial photograph as Drawing 2.
The Station property consists of wooded, open, and developed land just north of the James River. The
Station’s northern, eastern, and western boundaries are bordered by primarily undeveloped parcels, and
the Station is bordered to the south by a CSX rail line and the James River. Land use surrounding the
Station is classified as “A-1 Agricultural,” and consists of undeveloped wooded and agricultural properties
within a rural residential setting.
2.0 WASTEWATER SOURCES The Process Flow Diagram on Drawing 3 depicts the wastewater sources to the proposed West Treatment
Pond during the closure activities for the West (western portion), North, and East Ash Ponds, and the Metals
Pond. Drawing 4 is a Process Flow Diagram showing the final wastewater sources after the closure
activities are complete. These wastewater sources are described below.
CER: West Treatment Pond 2 Project No. 1520-347.300 Bremo Power Station June 2016 2.1 During Closure The following wastewater sources are expected to be routed to the West Treatment Pond during the closure
activities for the CCR impoundments and Metals Pond, as shown on Drawing 3.
2.1.1 Metals Pond Pumped Decant Water Metals Pond Pumped Decant Water is surface water that has accumulated in the Metals Pond and needs
to be removed as an initial step to facilitate closure. In the past, this water was periodically pumped to the
West Ash Pond via internal outfall 202 for ultimate discharge to the James River via outfall 002.
Decanting shall be accomplished by pumping the decant water to the centralized source water treatment
system (CSWTS) for treatment prior to discharge via internal outfall 504 or external outfall 002 via the West
Treatment Pond. Alternatively, the Metals Pond Pumped Decant Water may be transported off-site for
treatment and/or disposal at a permitted facility.
2.1.2 Metals Pond Contact Stormwater Metals Pond Contact Stormwater is stormwater that, following removal of the decant water, has contacted
the accumulated material in the Metals Pond during closure of the Metals Pond. Metals Pond Contact
Stormwater will need to be removed from the Metals Pond to facilitate closure. The Metals Pond Contact
Stormwater will be routed to the CSWTS for treatment prior to discharge via internal outfall 504 or external
outfall 002 via the West Treatment Pond. Alternatively, the Metals Pond Contact Stormwater may be
transported off-site for treatment and/or disposal at a permitted facility.
2.1.3 Metals Pond Material Dewatering Water Metals Pond Material Dewatering Water is the water that will be produced from dewatering the accumulated
material in the Metals Pond to allow for its removal and off-site disposal. This waste stream will be directed
to the CSWTS for treatment prior to discharge through internal outfall 504 or external outfall 002 via the
West Treatment Pond, or may be transported off-site for disposal at a permitted facility.
2.1.4 Ash Pond Decant Water Ash Pond Decant Water includes surface waters that result from the commingling of a number of
wastewater types, historically including but not necessarily limited to the following: ash pond contact
stormwater, low-volume Station wastewater, sewage treatment plant discharges, ash dewatering water,
and waters that are used to convey CCR to an impoundment through sluicing or dredging. As an initial
step in the process leading to closure of the ash impoundments, it will be necessary to remove the Ash
Pond Decant Water to dewater the CCR sufficiently to allow for preparation of a stable surface on which to
construct the closure cap, or to initiate CCR removal). Ash Pond Decant Water will be routed to the CSWTS
for treatment and discharge through internal outfall 504 or external outfall 002 via the West Treatment Pond,
or transported off-site for disposal at a permitted facility.
CER: West Treatment Pond 3 Project No. 1520-347.300 Bremo Power Station June 2016 2.1.5 Ash Pond Contact Stormwater Ash Pond Contact Stormwater is stormwater that has contacted the CCR in the North, East, and West Ash
Ponds, and is considered process wastewater. This waste stream will be directed to the CSWTS for
treatment prior to discharge through internal outfall 504 or external outfall 002 via the West Treatment Pond,
or transported off-site for disposal at a permitted facility.
2.1.6 Ash Pond Ash Dewatering Water Ash Pond Ash Dewatering Water is considered to be the pore water within the CCR mass in the West,
North, and East Ash Ponds. This wastewater refers to the water that is produced from dewatering the CCR
to stabilize the CCR and allow for its removal by mechanical dredging or excavation, or to support a closure
cap system. Ash Pond Ash Dewatering Water is generated from the CCR dewatering process through
mechanical means (e.g., vacuum wells, sump pumps, or other in situ withdrawal methods) and from cutting
drainage ditches and/or rim ditches into the CCR mass. Ash Pond Ash Dewatering Water will be directed
to the CSWTS for treatment prior to discharge through internal outfall 504 or external outfall 002 via the
West Treatment Pond, or transported off-site for disposal at a permitted facility.
2.1.7 Stormwater Treatment Pond Discharge Discharge from the Stormwater Treatment Pond is a potential wastewater source for the West Treatment
Pond during the closure activities for the North, East, and West Ash Ponds and the Metals Pond. Flow
from the Stormwater Treatment Pond is currently being discharged directly to Outfall 002 following filtration.
Once the West Treatment Pond is constructed, the Stormwater Treatment Pond will be directed to the West
Treatment Pond for solids removal via settling prior to discharge through Outfall 002.
2.2 Final Conditions The post-closure wastewater sources to the West Treatment Pond are shown on Drawing 4. After closure
of the CCR impoundments and Metals Pond, the discharge from the Stormwater Treatment Pond will
continue to be directed to the West Treatment Pond for treatment via settling. Some Station process waters,
low-volume waste and auxiliary process water may also be intermittently directed to the West Treatment
Pond.
3.0 WEST TREATMENT POND CONSTRUCTION Following removal of the CCR, the re-purposed eastern portion of the former West Ash Pond will be lined
with a 40-mil Ethylene Interpolymer Alloy (EIA) geomembrane liner system (XR-5) and placed back in
service as the West Treatment Pond with a discharge via outfall 002 (see Drawings 5 and 6 - West
Treatment Pond Modification Plan and Details). Construction of the West Treatment Pond will involve
removing the CCR and certifying the remaining soil subgrade as “clean closed.” CCR removal will be
considered complete based on a visual inspection determining the absence of CCR, followed by excavating
an additional 6 inches from the former West Ash Pond’s footprint.
CER: West Treatment Pond 4 Project No. 1520-347.300 Bremo Power Station June 2016 A new earthen fill embankment will be constructed across the pond to form the new western embankment
of the West Treatment Pond to a crest elevation of 234.0 feet above mean sea level (ft amsl). Additional
soil fill will be placed on the interior slopes of the existing embankments to flatten the slopes from 2H:1V to
3H:1V and to add an 8-foot-wide safety bench at elevation 228.0 ft amsl. Once the West Treatment Pond
embankments are complete, the remainder of the former West Ash Pond and Metals Pond embankments
will be removed, and the remainder of the former pond area to the west of the new West Treatment Pond
will be graded to drain and seeded.
The existing concrete intake tower will be modified slightly to eliminate the removable stop logs and install
a permanent discharge weir crest at elevation 230.0 ft amsl. The outlet weir will have a crest length of
5.5 feet. The existing 42-inch diameter corrugated metal pipe outlet at the base of the tower will remain
and continue to the James River through a series of junction boxes, manholes, and pipes via outfall 002.
As part of the pond closure project, it is planned to slip-line this pipe to increase its longevity.
The XR-5 liner will be underlain by an 8-ounce non-woven cushion geotextile installed over a prepared and
inspected subgrade in accordance with the project specifications. Penetrations into the pond liner for the
10-inch diameter stormwater discharge pipe and the 8-inch diameter process water pipe from the station
will be secured and booted to provide a watertight seal. The liner will also be connected to the concrete
outlet tower near the base of the tower using a batten strip connection for water tightness. Construction
Quality Assurance (CQA) oversight during construction will be carried out by third-party inspectors in
accordance with the approved CQA Plan. Documentation of the installation, including liner and geotextile
deployment, nondestructive and destructive seam testing, repairs, and surveyed record drawings, will be
prepared and certified by a licensed professional engineer.
3.1 West Treatment Pond Capacity Once constructed, the normal pool volume of the West Treatment Pond will be approximately
19,875,000 gallons as measured at the spillway crest (elevation 230.0 ft amsl). At normal pool, the pond
has a freeboard of 4 feet. The pond does not have a contributing drainage area other than the pond area
itself, approximately 5.9 acres, so stormwater inflows from large storm events are limited to what falls within
the pond. The modeled high water level for the 24-hour, 100-year storm event is elevation 231.0 ft amsl.
3.2 Dam Safety Due to the capacity of the West Treatment Pond being greater than 50 acre-feet (16,300,000 gallons), the
West Treatment Pond is regulated under the Virginia Department of Conservation and Recreation (DCR)
Dam Safety Program. The West Treatment Pond is anticipated to receive a Hazard Potential Classification
of “Low” once construction is complete. Requirements under the DCR certificate include annual
inspections, inspection by a licensed professional engineer every 6 years, maintenance of an emergency
preparedness plan, and development of breach inundation maps.
DRAWINGS
SITE LOCATION MAP
DRAWING 1DOMINION - BREMO POWER STATION
DATE
CHECK
REVIEW
DESIGN
CADD
REV.
PROJECT No.
SCALE
TITLE
AS SHOWN
Richmond, Virginia BPG
JRD
12/18/15
0
15-20347
G:\P
lan
Pro
duct
ion
Dat
a Fi
les\
Dra
win
g D
ata
File
s\15
-203
47\N
-
CE
R W
ater
Tre
atm
ent\A
ctiv
e D
raw
ings
\152
0347
N01
.dw
g
02000 2000
SCALE FEET
SITEAREA
WEST ASHPOND
EAST ASHPOND
NORTH ASHPOND
BASE MAP CONSISTS OF 7.5-MINUTE USGS TOPOGRAPHICQUADRANGLE NAMED ARVONIA, VIRGINIA, DATED 2013.
REFERENCE
JRD
DPM
METALSPOND
WEST ASH PONDWEST ASH POND
EAST ASH PONDEAST ASH POND
NORTH ASH PONDNORTH ASH PONDMHMH
MHMH
RISERRISER
OUTFALL 002OUTFALL 002
OUTFALL 202OUTFALL 202METALSMETALS
PONDPOND
OUTFALL 204OUTFALL 204
BREMOBREMOPOWER STATIONPOWER STATION
OUTFALL 001OUTFALL 001
OUTFALL 006OUTFALL 006
~JAMES RIVER~
~JAMES RIVER~
BREMO ROAD
BREMO ROAD
BREMO ROADBREMO ROAD
BRICK ARCHBRICK ARCHCULVERTCULVERT
~HO
LMA
N C
REEK
~~H
OLM
AN
CR
EEK~
CULVERTCULVERT
OUTFALL 004OUTFALL 004
OUTFALL 003OUTFALL 003
RISERRISER
RISERRISER
OUTFALL 203OUTFALL 203
CSXCSX
CSXCSXLEGENDLEGEND
- OUTFALL CONVEYANCE SYSTEM- OUTFALL CONVEYANCE SYSTEM
- APPROXIMATE PROPERTY BOUNDARY- APPROXIMATE PROPERTY BOUNDARY
- APPROXIMATE LIMITS OF ASH POND- APPROXIMATE LIMITS OF ASH POND
STORMWATER PONDOVERFLOW DISCHARGE(KNIFE GATE VALVE)
STORMWATER PONDOVERFLOW DISCHARGE(KNIFE GATE VALVE)
BRICK ARCHBRICK ARCH
COAL YARD(CLOSED)COAL YARD(CLOSED)
OUTFALL 101OUTFALL 101
EXISTINGNORTH PONDTOE DRAINS
EXISTINGNORTH PONDTOE DRAINS
DISCHARGE FROMSTORMWATER PONDTO WEST POND(OUTFALL 204)
DISCHARGE FROMSTORMWATER PONDTO WEST POND(OUTFALL 204)
STORMWATERSTORMWATERPONDPOND
0250 250 500
SCALE FEET
1 09/23/15 PER DEQ COMMENTS JRD ABM ATN JRD
DRAWING 2
DOMINIONBREMO POWER STATION
CCR IMPOUNDMENT CLOSUREVPDES PERMIT APPLICATION AMENDMENT
TITLE
PROJECT
SCALEDESIGN
PROJECT No. FILE No.
CADD
CHECK
REVIEW
REVISION DESCRIPTION CADD CHK RVWDESDATEREV
G:\P
lan
Pro
duct
ion
Dat
a Fi
les\
Dra
win
g D
ata
File
s\15
-203
47\H
-
Per
mit
App
licat
ion
Am
endm
ent\A
ctiv
e D
raw
ings
\152
0347
H02
.dw
g | L
ayou
t: 2
EX
ISTI
NG
OU
TFA
LL L
OC
ATI
ON
MA
P | M
odifi
ed: a
bmar
tin09
/23/
2015
3:3
4 P
M |
Plo
tted:
abm
artin
09/2
5/20
15
15-20347 1520347H02
AS SHOWNJRD 06/27/15
ATN 06/27/15
ATN 06/30/15
JRD 06/30/15
SITE PLAN
1 09/23/15 PER DEQ COMMENTS JRD ABM ATN JRD
TITLE
PROJECT
SCALEDESIGN
PROJECT No. FILE No.
CADD
CHECK
REVIEW
REVISION DESCRIPTION CADD CHK RVWDESDATEREV
G:\P
lan
Pro
duct
ion
Dat
a Fi
les\
Dra
win
g D
ata
File
s\15
-203
47\H
-
Per
mit
App
licat
ion
Am
endm
ent\A
ctiv
e D
raw
ings
\152
0347
H03
-05.
dwg
| Lay
out:
SH
T 5
| Mod
ified
: abm
artin
09/2
5/20
15 1
1:32
AM
| P
lotte
d: a
bmar
tin09
/25/
2015
15-20347 1520347H03-05
AS SHOWNJRD 06/27/15
ATN 06/27/15
ATN 06/30/15
JRD 06/30/15
PROCESS FLOW DIAGRAM(STAGE II CONSTRUCTION)
2016-2018 TIME FRAME
DRAWING 3
CONTACT STORMWATERAND ASH DEWATERING WATER
4.0 MGD AVG(6.0 MGD MAX)3
DOMINIONBREMO POWER STATION
CCR IMPOUNDMENT CLOSUREVPDES PERMIT APPLICATION AMENDMENT
OUTFALL FLOW SUMMARY TABLE
SOURCE WATER AVG. FLOW MAX. FLOW
OUTFALL 001 91.8 MGD 172.8 MGD2
OUTFALL 002 1.53 MGD/5.53 MGD 4.2912 MGD2/10.2912 MGD
OUTFALL 204 >1.26 MGD/5.26 MGD >1.26 MGD1/7.26 MGD
OUTFALL 003 4.0 MGD 6.0 MGD3
OUTFALL 004 0.204/4.0 MGD 0.4090/6.0 MGD3
OUTFALL 006 4.0 MGD 6.0 MGD3
NON-CONTACTSTORMWATERDISCHARGE
(PRECIPITATIONDEPENDENT)
4.0 MGD AVG6.0 MGD MAX3
(IF FROMTREATMENT
SYSTEM)
UNDER FLOWSOLIDS
4.0 MGD AVG6.0 MGD MAX3
4.0 MGD AVG(6.0 MGD MAX)3
91.8 MGD AVG(172.8 MGD MAX)2
91.8 MGD AVG172.8 MGD MAX2
1.61 MGD AVG(1.61 MGD MAX)1
1.61 MGD AVG(1.61 MGD MAX)1
4.0 MGD AVG(6.0 MGD MAX)3
(PRECIPITATIONDEPENDENT)
CONSTRUCTIONNON-CONTACTSTORMWATER
(PRECIPITATIONDEPENDENT)
OUTFALL 204
1.53 MGD AVG4.2912 MGD MAX2
(+4.0 MGD AVG/+6.0 MGD3 MAX IF
FROM TREATMENTSYSTEM)
1.53 MGD AVG(4.2912 MGD MAX)2
(+4.0 MGD AVG/+6.0 MGD MAX3
IF FROM TREATMENTSYSTEM)
>1.26 MGD AVG(>1.26 MGD MAX)1
(+4.0 MGD AVG/+6.0 MGD MAX3
IF FROMTREATMENT
SYSTEM)
1.26 MGD AVG(1.26 MGD MAX)1
4.0 MGD AVG(6.0 MGD MAX)3
NOTES:1. WHERE FLOWS ARE LIMITED BY SYSTEM DESIGN, MAXIMUM FLOWS EQUAL THE AVERAGE
FLOWS.2. IF THE MAXIMUM FLOWS ARE LISTED IN THE PERMIT, THOSE FLOWS WERE USED.3. WHERE FLOWS ARE NOT LIMITED BY SYSTEM DESIGN AND MAXIMUM FLOWS WERE NOT LISTED
IN THE PERMIT, MAXIMUM FLOWS WERE CALCULATED BY MULTIPLYING THE AVERAGE FLOWS BYA FACTOR OF 1.5.
4. FLOWS FROM OUTFALL 101 ARE INCLUDED IN THE FLOWS IDENTIFIED FOR OUTFALL 001.5. FLOWS FROM THE STORMWATER MANAGEMENT POND ARE INCLUDED IN THE FLOWS FROM THE
WEST TREATMENT POND.6. FLOWS FROM THE METALS POND ARE INCLUDED IN THE FLOWS FROM THE WEST TREATMENT
POND.7. FLOWS FROM OUTFALL 002, 003, 004, AND 006 WILL INCREASE AS SHOWN IF FLOWS FROM THE
NORTH AND EAST ASH POND TREATMENT SYSTEM ARE INCLUDED.
4.0 MGD AVG6.0 MGD MAX3
(IF FROMTREATMENT
SYSTEM)
0.204 MGD AVG(0.4090 MGD MAX)2
(PRECIPITATIONDEPENDENT)
0.204 MGD AVG0.4090 MGD MAX2
(4.0 MGD AVG6.0 MGD MAX3
IF FROMTREATMENT
SYSTEM)STAGE I & II CONTACT
STORMWATER AND ASHDEWATERING WATER
1.53 MGD AVG(4.2912 MGD MAX)2
1.53 MGD AVG(4.2912 MGD MAX)2
(PRECIPITATIONDEPENDENT)
1.53 MGD AVG4.2912 MGD MAX2
(+4.0 MGD AVG/+6.0 MGD3 MAX IF
FROM TREATMENTSYSTEM)
STAGE II CONTACTSTORMWATER AND
MATERIAL DEWATERINGWATER
1.0146 MGD AVG(1.6138 MGD MAX)2
(PRECIPITATIONDEPENDENT)
OUTFALL 202
1.0146 MGD AVG(1.6138 MGD MAX)3
STAGE II PUMPEDDECANT WATER1.0146 MGD AVG
(1.6138 MGD MAX)2
CONSTRUCTION NON-CONTACTSTORMWATER (POST CCR AND
METALS POND MATERIALREMOVAL)
1.0146 MGD AVG(1.6138 MGD MAX)3
UNDER FLOWSOLIDS
VIRGINIA STORMWATER MANAGEMENT PROGRAM
ENHANCED TREATMENT (AS NEEDED)
SOURCE WATER AND OUTFALLS
SOLIDS REMOVAL
TABLE 4 REFERENCE
SAMPLING LOCATION
INTERMITTENT FLOW
LEGEND
1D
SS
S
S2G
S S
S
S
2B
2A
S
S2F
2D
2E
2C
S
UNDER FLOWSOLIDS
1.53 MGD AVG(4.2912 MGD MAX)2
S
JAMES RIVER
RIVER INTAKE SCREEN
TRAVELING SCREENS
OUTFALL 1011.613 MGD
OUTFALL 001 INTO THE JAMES
RIVER 91.8 MGD*
OUTFALL 2030.008 MGD*
OUTFALL 002INTO THE JAMES RIVER
1.53 MGD*
OUTFALL 006 NON CONTACT STORMWATER
TO THE JAMES RIVER
OUTFALL 008NON CONTACT STORMWATER
TO THE JAMES RIVER
TURBINE GENERATOR
MAIN CONDENSERS
TURBINE GENERATOR HYDROGEN COOLERS
TURBINE GENERATOR OIL
COOLERS
BOILER FEED PUMP NON CONTACT COOLING WATER
CIRCULATING WATER SYSTEM
POLISHING FILTERSGRAVITY
FILTERS
REJECT WATER 0.0432 MGD
DEICING WATER SYSTEM
DOMESTIC WATER WELL
SEWAGE TREATMENT
PLANT
STORMWATER
DEMINERALIZATION DEIONIZATION
SYSTEM 125 gpm
BOILER UNITS 3&4COMBINED
BLOWDOWN 0.0418 MGD
EMERGENCY FIRE PUMP
BOILER UNITS 3&4
SCREENWASH 1.613 MGD
BOILER CLEANING
OFF-SITE DISPOSAL
LOW VOLUME WASTE
AUXILLARY PROCESS
WATER 2.592 MGD
CLOSED & CAPPED
NORTH ASH POND
WEST TREATMENT POND
STORMWATER TREATMENT PONDOUTFALL 204
SCREEN WELL
LEAKAGE
ADMIN BLDGMAINT SHOP
COAL YARD BLDGSTOREROOM
BEARING COOLING WATER
& AUXILLARY
SYSTEM 1.1434 MGD
SEENOTE 1
BACKWASH
0.0254 MGDBACKWASH
SPRAY WATER
179.3 MGD (MAX)
BREMO POWER STATION STATION WATER FLOW
POST CONSTRUCTION (FINAL)ONE LINE DIAGRAM
REVISED 9/2015
0.2232MGD
0.18MGD
SEE NOTE 3
TOE DRAINS
CLOSED & CAPPED
EAST ASH POND
OUTFALL 007NON CONTACT STORMWATER
TO THE JAMES RIVER
TOE DRAINS
BEARING COOLING WATER
SEENOTE 2
FIRE WATER TANK
NOTES:- DASHED LINES REPRESENT INTERMITTENT DISCHARGE.- DURING ALTERNATE RAW WATER SYSTEM OPERATION, BOILER FEED PUMP NON-CONTACT COOLING WATER MAY BE USED AS SYSTEM MAKE-UP WATER.- FLOW IS BASED ON DESIGN CAPACITY UNLESS DENOTED BY (*) WHICH INDICATES AVERAGE FLOW DERIVED FROM THE 8/2010-8/2014 DMRS.1. ALTERNATE WATER SUPPLY WILL RECIRCULATE 2.8 MGD AND NORMALLY WILL NOT INTERFACEWITH RIVER.2. DEICING WATER IS USED ONLY DURING SEVERE COLD WEATHER.3. COUNTY WATER IS USED WHEN RIVER WATER IS TOO TURBID FOR USE AS MAKE-UP WATER.
DRAWING 4
●
●
●
●
●
●
●●
●
●
●
●
●
●
●
●
●●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●●
●
●
●
●
●
●
●
●
●
●
●
●
●
●●
●
●
●
●
●
●
●
●
●
●
●
●
●
MW-3
MW-1
MW-2
MW-12
R
P
A
R
P
A
RP
A
RP
A
R
P
A
R
P
A
R
P
A
R
P
A
R
P
A
R
P
A
R
P
A
R
P
A
R
P
A
R
P
A
R
P
A
R
P
A
R
P
A
R
P
A
R
P
A
R
P
A
R
P
A
RP
A
R
P
A
R
P
A
R
P
A
R
P
A
RP
A
R
P
A
R
P
A
R
P
A
R
P
A
2
2
0
2
3
0
220
2
3
0
216
216
2
3
0
2
0
0
2
1
0
2
2
0
2
2
0
2
2
0
2
2
0
2
3
0
2
3
0
2
1
8
2
1
8
2
2
0
2
0
0
2
0
0
2
1
0
2
1
0
2
2
0
2
1
0
2
1
0
216
2
1
0
2
1
0
2
2
0
2
3
0
2
2
0
2
2
0
2
2
0
2
3
0
218
2
1
4
2
1
2
2
1
0
2
1
0
2
1
0
2
1
0
2
1
0
220
230
220
230
210
2
2
0
2
2
0
2
3
0
2
1
8
2
1
6
3
:
1
MW-3
MW-2
MW-12
B
R
E
M
O
R
O
A
D
C
S
X
R
A
IL
R
O
A
D
~
J
A
M
E
S
R
I
V
E
R
~
EXISTING OUTLET
STRUCTURE
TO BE MODIFIED
(BATTEN STRIP LINER
TO EX. STRUCTURE)
EXISTING INFLOW
FROM STATION
EXISTING VPDES
OUTFALL 002
H
O
L
M
A
N
C
R
E
E
K
PROPOSED
10' GRAVEL
ACCESS ROAD
WEST
TREATMENT
POND
EXPOSED
XR-5
GEOMEMBRANE
VOL = 61.0 AC-FT
AT NORMAL POOL
(EL 230)
LIMITS OF
EXPOSED LINER /
ANCHOR TRENCH
+ 211.5
+ 211.5
PROPOSED 12"
DISCHARGE PIPE
(FROM STATION) TO
WEST TREATMENT
POND
PROPOSED RISER AND
DISCHARGE PIPE
EXISTING CHAIN LINK
FENCE TO REMAIN
3
DCR-12
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
PROPOSED GATE
PROPOSED CHAIN
LINK FENCE
(TIE INTO EXISTING)
212
220
228
230
232
234
222
224
212
220
228
230
232
2
1
8
2
1
8
216
216
216
2
1
4
228.08
8' SAFETY
BENCH
8' SAFETY
BENCH
REMOVE TREES WITHIN 25
FT. OF TOE OF DAM (TYP.)
REMOVE TREES WITHIN 25
FT. OF TOE OF DAM (TYP.)
2
.
0
:
1
3
.
0
:
1
3.0:1
3
.
0
:
1
3.0:1
3.0:1
3.0:1
PROPOSED
GATE
2
1
9
2
1
9
WEST STORMWATER
DETENTION POND
A
A'
B
B
'
CLASS 1 RIPRAP
OUTLET PROTECTION
L=10', W=10', D=2'
1
DCR-3
PROPOSED 12"
DISCHARGE PIPE (FROM
STATION)
2
DCR-3
3
DCR-3
EXISTING DISCHARGE PIPE
(FROM STORMWATER
MANAGEMENT POND) TO REMAIN
3
DCR-3
LIMITS OF
EXPOSED LINER /
ANCHOR TRENCH
EXISTING
MANHOLE
EL
EV
AT
IO
N (F
T)
200
210
220
230
240
250
260
270
0+00 0+40 0+80 1+20 1+60 2+00 2+40 2+80 3+20 3+60 4+00 4+40 4+80 5+20 5+60
NORMAL WATER EL. = 230.00
100 YR. WATER EL. = 230.98
BOTTOM EL. = 211.50
(EXPOSED LINER)
PROPOSED GRADE
(EXPOSED LINER)
EXISTING GRADE
(POST-CCR
REMOVAL)
EMBANKMENT MATERIAL
(SEE NOTE BELOW)
8 FT. SAFETY BENCH
EL. = 228.00
EXPOSED GEOMEMBRANE
ANCHOR TRENCH
1
3
3
DCR-3
EL
EV
AT
IO
N (F
T)
200
210
220
230
240
250
260
270
5+60 6+00 6+40 6+80 7+20 7+60 8+00 8+40 8+80 9+20 9+60 10+00 10+40 10+80
EMBANKMENT MATERIAL
(SEE NOTE BELOW)
WEST
STORMWATER
DETENTION POND
NORMAL WATER EL. = 230.00
100 YR. WATER EL. = 230.98
BOTTOM EL. = 211.50
(EXPOSED LINER)
EXISTING GRADE
(POST-CCR
REMOVAL)
EXPOSED GEOMEMBRANE
ANCHOR TRENCH
8 FT. SAFETY BENCH
EL. = 228.00
PROPOSED GRADE
(EXPOSED LINER)
1
3
1
3
3
DCR-3
EL
EV
AT
IO
N (F
T)
EL
EV
AT
IO
N (F
T)
200
210
220
230
240
250
260
270
200
210
220
230
240
250
260
270
0+00 0+40 0+80 1+20 1+60 2+00 2+40 2+80 3+20 3+60 4+00 4+40 4+80 5+20
10 ft
4 ft
15 ft
NORMAL WATER EL. = 230.00
100 YR. WATER EL. = 230.98
TOP OF DAM
EL. = 234.00
8 FT. SAFETY BENCH
EL. = 228.00
EXISTING OUTLET
STRUCTURE TO BE
MODIFIED
EXISTING EMBANKMENT
EXISTING 42" CMP
OUTLET PIPE TO BE SLIP
LINED WITH CURE-IN-
PLACE LINING TUBE
BOTTOM EL. = 211.50
(EXPOSED LINER)
EMBANKMENT
MATERIAL
(SEE NOTE
BELOW)
PROPOSED
GRADE
EXISTING GRADE
(POST-CCR
REMOVAL)
8 FT. SAFETY BENCH EL. = 228.00
EXISTING
MANHOLE
EXPOSED GEOMEMBRANE
ANCHOR TRENCH
EMBANKMENT MATERIAL
(SEE NOTE BELOW)
1
1
1
3
1
3
1
3
1
3
(TYP.)
3
DCR-3
1
DCR-3
G:\P
lan P
roduction D
ata F
iles\D
raw
ing D
ata F
iles\15-20347\N
- C
ER
W
ater T
reatm
ent\A
ctive D
raw
ings\1520347N
02.dw
g
0
100 100
SCALE FEET
WE
ST
T
RE
AT
ME
NT
P
ON
D
MO
DIF
IC
AT
IO
N P
LA
N
DO
MIN
IO
N
BR
EM
O P
OW
ER
S
TA
TIO
N
CC
R S
UR
FA
CE
IM
PO
UN
DM
EN
T
WE
ST
T
RE
AT
ME
NT
P
ON
D C
ER
FL
UV
AN
NA
C
OU
NT
Y, V
IR
GIN
IA
DRAWING 5
DESIGN
PROJECT No.
CADD
CHECK
REVIEW
FILE No.
SCALEREV.
RE
VIS
IO
N D
ES
CR
IP
TIO
NC
AD
DC
HK
RV
WD
ES
DA
TE
RE
V
TIT
LE
PR
OJE
CT
15-20347
1520347N02
0 AS SHOWN
JRD 02/05/15
ATN 02/05/15
WEST TREATMENT POND PLAN
WEST TREATMENT POND SECTION B-B'
WEST TREATMENT POND SECTION B-B'
WEST TREATMENT POND SECTION A-A'
MA
TC
HL
IN
E (S
EE
B
EL
OW
)
MA
TC
HL
IN
E (S
EE
A
BO
VE
)
(STA 0+00 - 5+60)
(STA 5+60 - 10+86)
THE EMBANKMENT SOILS ARE SPECIFIED TO BE LOW TO MODERATE
PLASTICITY SOIL (PI LESS THAN 30), GENERALLY FREE OF ORGANIC
MATTER AND OTHER DELETERIOUS MATERIALS AND ROCK FRAGMENTS
LARGER THAN 2 INCHES IN ANY DIMENSION. EMBANKMENT SOILS WILL
BE COMPACTED IN LIFTS TO AT LEAST 95% OF STANDARD PROCTOR
DRY DENSITY. SEE TECHNICAL SPECIFICATIONS FOR COMPLETE
MATERIAL DESCRIPTION, INSTALLATION, AND TESTING REQUIREMENTS.
EMBANKMENT MATERIAL NOTE
040 40
SCALE FEET
0
20
20
SC
AL
EF
EE
T
EL. 214.00
5
.
5
f
t
E
L
.
2
3
0
.
0
0
E
L
.
2
1
4
.
0
0
E
L
.
2
3
3
.
6
5
E
L
.
2
0
7
.
1
5
EL. 207.15
EL. 230.00
EL. 233.65
SECTION A-A'
A
'
DCR-3
1
NOT TO SCALE
FORMED CONCRETE
FROM ELEV. 214.00 TO
ELEV. 230.00
EXISTING 42" CMP OUTLET
PIPE TO BE SLIP LINED WITH
CURED-IN-PLACE LINING TUBE
EXISTING OUTLET STRUCTURE
MODIFICATION DETAIL
ISOMETRIC VIEW
A
EXISTING 42" CMP
OUTLET PIPE
EXISTING WEIR WITH
SLOTTED SIDES FOR
WOODEN BAFFLES TO BE
FILLED WITH FORMED
CONCRETE UP TO EL. 230.00
(SEE NOTES BELOW)
TEMPORARY
WOODEN
FORMS
BATTEN STRIP FOR
EXPOSED LINER (ALL
SIDES OF OUTLET
STRUCTURE)
PROPOSED GRADE
(EXPOSED LINER)
3
1
2
DCR-12
EXISTING HANDRAIL AND
WALKWAY TO BE REMOVED AND
REPLACED
CONCRETE BONDING AND FINISHING NOTES
1. 1. ALL CONCRETE CONSTRUCTION SHALL BE IN ACCORDANCE WITH ACI 318, "BUILDING
REQUIREMENTS FOR STRUCTURAL CONCRETE".
2. ALL CONCRETE SHALL OBTAIN A 28-DAY COMPRESSIVE STRENGTH OF 3,000 PSI (MINIMUM) AND
SHALL CONTAIN AN AIR ENTRAINING MIXTURE TO OBTAIN AN AIR CONTENT OF 6% ± 2%.
3. ALL REINFORCING STEEL SHALL BE ASTM A-615 GRADE 60.
4. EXISTING SURFACES TO RECEIVE ADDITIONAL CONCRETE APPLICATIONS SHALL BE BROOM
CLEANED AND CONCRETE CLEANER APPLIED TO REMOVE FOREIGN MATERIAL THAT WOULD
PREVENT ADHESION. DUE TO THE PROXIMITY OF THIS STRUCTURE TO THE POND AND STREAM
OUTFALL, CAREFUL APPLICATION AND CLEANUP OF CLEANER IS VERY IMPORTANT.
5. DRILL THE EXISTING CONCRETE AND INSTALL 6-INCH LONG, #4 REBAR DOWEL PINS. PINS SHALL
BE EMBEDDED THREE INCHES INTO THE EXISTING CONCRETE AND SECURED WITH A
WATERPROOF EPOXY SUITABLE FOR THIS APPLICATION. DOWELS SHALL BE INSTALLED ALONG
THE CENTERLINE OF THE EXISTING WALL THICKNESS.
6. CONCRETE SHALL BE PROTECTED FROM DRYING AND/OR FREEZING FOR 72 HOURS FOLLOWING
PLACEMENT.
7. REINFORCE CONCRETE WITH 4X4-W2.0XW2.0 WELDED WIRE FABRIC.
PERIMETER
ACCESS ROAD
2'x2' ANCHOR
TRENCH
3 ft
EXPOSED
XR-5 GEOMEMBRANE
6" (MIN.)
3
1
8 ft
SAFETY BENCH
1% MIN.
10 ft
3
1
3 ft
EXTRUSION WELD
(ALL SIDES)
EL. 230.00
(NORMAL POOL)
DCR-3
2
NOT TO SCALE
DISCHARGE PIPE FROM STATION
LINER PENETRATION DETAIL
EL. 233.00
EL. 228.00
PROPOSED 12"
DISCHARGE PIPE
(FROM STATION)
PROPOSED
SAFETY FENCE
15 ft
PIPE
CLAMPS
(M
IN
.)
3
DCR-12
PERIMETER
ACCESS ROAD
2'x2' ANCHOR
TRENCH
COMPACT PER
TECHNICAL
SPECIFICATIONS
3 ft
EXPOSED
XR-5 GEOMEMBRANE
6" min.
3
1
8 ft
SAFETY BENCH
1% MIN.
EL. 230
(NORMAL POOL)
10 ft
15 ft
8OZ NON-WOVEN
GEOTEXTILE
PROPOSED
SAFETY FENCE
FLAP VENT
@100' ON CENTER
3
1
DCR-3
3
NOT TO SCALE
WEST TREATMENT POND SAFETY
BENCH AND ANCHOR TRENCH DETAIL
4
DCR-3
3
DCR-12
EL. 228.00
TOP OF BERM
12"
1'x1' XR-5 FLAP
EXTRUSION WELD
(3 SIDES ONLY)
4"Ø HOLE IN LINER
AT CENTER OF
FLAP
DOWN SIDE OF
FLAP IS OPEN
XR-5
GEOMEMBRANE
DCR-3
4
NOT TO SCALE
FLAP VENT DETAIL
G:\P
lan P
roduction D
ata F
iles\D
raw
ing D
ata F
iles\15-20347\N
- C
ER
W
ater T
reatm
ent\A
ctive D
raw
ings\1520347N
02.dw
g
WE
ST
T
RE
AT
ME
NT
P
ON
D
MO
DIF
IC
AT
IO
N D
ET
AIL
S
DRAWING 6
DESIGN
PROJECT No.
CADD
CHECK
REVIEW
FILE No.
SCALEREV.
RE
VIS
IO
N D
ES
CR
IP
TIO
NC
AD
DC
HK
RV
WD
ES
DA
TE
RE
V
TIT
LE
PR
OJE
CT
15-20347
1520347N02
0 AS SHOWN
JRD 02/05/15
ATN 02/05/15
DO
MIN
IO
N
BR
EM
O P
OW
ER
S
TA
TIO
N
CC
R S
UR
FA
CE
IM
PO
UN
DM
EN
T
WE
ST
T
RE
AT
ME
NT
P
ON
D C
ER
FL
UV
AN
NA
C
OU
NT
Y, V
IR
GIN
IA