I
903R88108
• United States Environmental Protection Agency
CEPfTRS 17/88
October 1988
Assessment of Cost and
Effectiveness of Biological Dual
Nutrient Removal Technologies
in the Chesapeake Bay
Drainage Basin
Volume
U.S. fnvironmfital Protection Agency
Region III inioi (nation Resource
Centei (3PM52)
&41 Chestnut Street
hia, PA 19107
TD
225
.C54
W191
Vol. 2
Chesapeake
Bay
Program
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v"'' U.S. Environmental Pr«tetiw »|lfl Reg-en Til IntoiTutiflJi Resoutd
Center (3PM52)
841 Chestput Street
Philadelphia, PA 19107
ASSESSMENT OF COST AND EFFECTIVENESS
OF BIOLOGICAL DUAL NUTRIENT
REMOVAL TECHNOLOGIES IN THE
CHESAPEAKE BAY DRAINAGE BASIN
VOLUME II
PREPARED BY
HAZEN AND SAWYER ENGINEERS, P.C.
730 BROADWAY
NEW YORK, NEW YORK 10003
AND
J. M. SMITH AND ASSOCIATES, PSC.
CONSULTING ENGINEERS
7373 BEECHMONT AVENUE
CINCINNATI, OHIO 45230
CONTRACT NO. 68-03-4049
PREPARED FOR
UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
PERFORMANCE ASSURANCE BRANCH
MUNICIPAL FACILITIES DIVISION
WASHINGTON, D.C. 20460
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TABLE OF CONTENTS
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TITLE APPENDIX
INTRODUCTION
ARLINGTON WPCP, VIRGINIA D-l
HOPEWELL WPCP, VIRGINIA D-2
LOWER POTOMAC WPCP,
FAIRFAX, VIRGINIA D-3
PATAPSCO WWTP,
BALTIMORE, MARYLAND D-4
ALEXANDRIA WPCP, VIRGINIA D-5
RICHMOND WWTP, VIRGINIA D-6
BACK RIVER WWTP, MARYLAND __ D-7
BLUE PLAINS WWTP,
WASHINGTON, D.C. D-8
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Introduction
The purpose of this report entitled "Assessment of the
Cost and Effectiveness of Biological Dual Nutrient Removal
Technologies in the Chesapeake Bay Drainage Basin, Volume II"
is to present the cost of retrofitting BNR processes to eight
of the largest plants in the Chesapeake Bay Drainage Basin.
The plants selected for this report along with their design
flows are listed below:
Plant Name and Location
Arlington WWTP, VA
Hopewell WWTP, VA
LPPCP, Fairfax, MD
Patapsco WWTP, Baltimore, MD
Alexandria WWTP, VA
Richmond WWTP, VA
Back River WWTP, Baltimore, MD
Blue Plains WWTP, Washington, DC
Design Flow
(mgd)
30
50
54
70
56
70
207
309
Contact Person
Mr. Alan Cassell
Mr. Mark Haley
Mr. Alan Hogge
Mr. Jerry Slattery
Mr. Glenn Harvey
Mr. Ben Gregory
Mr. Jerry Slattery
Mr. Russ Thomas
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The two levels of treatment and the corresponding BNR
technologies used for estimating costs of retrofitting these
plants are the same as described in Volume I of this report.
The methodology adopted for this report was to use site
specific data and existing facilities for the evaluation of
each of these plants. The plant specific data and details of
the existing facilities were obtained from the following
sources:
Review of available facility plans.
Preliminary and final design reports.
Existing as-built plans.
Existing and proposed permits.
Plant performance data.
Interviews with plant officials/staff.
All of the cost estimates presented in this report are
based on the design flows of the plants at two levels of
nutrient removal, i.e., HLND (TN - 8 mg/1; TP » 2 mg/1) and
LLND
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Comparison of the planning level cost estimates presented
herein to those generated by much more detailed analysis must
be made with extreme caution. Large variations in cost may be
attributed to the following:
• levels of TP and TN removal to be achieved on a
long-term average basis.
• level of reliability expected
• short or long-term plans for disposal of residuals.
Almost all of the plants evaluated were in various stages
of facility planning, design or construction for upgrading
effluent quality, expansion of capacity or both. For some
plants, cost estimates have been prepared for chosen
alternatives based on detailed facility plans and/or final
design reports. Much of this effort is being accomplished
under sponsorship of the U.S.E.P.A. Construction Grant
Program.
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ARLINGTON WATER POLLUTION
CONTROL PLANT
APPENDIX D-L
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TABLE OF CONTENTS
SECTICN PAGE
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• 1.0 Description of Existing Facilities 1
• 2.0 Proposed Plant Modifications 8
3.0 Proposed Retrofiting for Biological
• Nutrient Removal 8
4.0 Total Cost Sunmary 14
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APPENDIX D-l
ARLINGTON WATER POLLUTION CONTROL PLANT
1.0 DESCRIPTION OF EXISTING FACILITIES:
The Arlington, Virginia Hater Pollution Control Plant serves as a major
domestic waste treatment facility. The wastewater treatment facilities
consist of prechlorination, grit and screening removal, primary clarification,
aeration, secondary clarification, chemical addition, tertiary clarification,
multi-media gravity filtration, reaeration, and post chlorination.
Sludge from the primary clarifier, flotation thickener, and the secondary
clarifiers is dewatered by the filter press and then incinerated. The ash is
disposed of in a sanitary landfill.
Figure D.l.l is a schematic of the existing plant showing the wet unit
processes and the sludge treatment and handling facilities. Figure D.I.2 is a
layout of the Arlington plant site. As can be seen the present treatment
plant is confined on all four sides. Land area for expansion and/or
modification is very i/i mi *•***. The flow diagrams for the proposed retrofitting
for HLND and LUD are indicated in figures D.l.3 and D.I.4.
Present design flow and wastewater characteristics:
The present design flow is 30 M3). The average flow monitored in FY 85 and FY
86 was 26 M3D.
From Table D.l.l it can be seen that the treatment plant performance is
excellent in meeting the effluent limits for BCD, TSS and Phosphorus. The
plant presently does not have any nitrogen limitations but has a 0.18 mg/1
monthly average limit for total phosphorus.
Although the plant has had considerable problems in operating the gravity
filters for the past two years, the treatment plant officials decided to use
the gravity filters because of the availability of spare parts, not being used
used by the Fairfax County treatment plant.
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TABLE D.I.I
ARLINGTON WWTP RAW SEWAGE AND EFFLUENT CHARACTERISTICS
Parameter Influent, mq/1Effluent, mg/1% Removal NPDES Permit
BOD5, mg/1 156 6 96 10
TSS, mg/1 197 6 97 10
TKN, mg/1 38 10 — N/A
NH3, mg/1 18 8 56 N/A
Phosphorus, mg/1 10 0.18 90 0.18
Fecal Coliform No/1000 ml 200 — 200
pH 7.5 7.3 — 6-9
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Existing plant components and sizes:
Primary Treatment;
Second ^y
Tertiary Treatment;
Primary settling tanks (4), each 188' L x 32' W x 9.6'
D, overflow rate of 2500 gpd/sq. ft (peak) .
Sludge collectors (4), 1 HP; 1,720 rpm; 220/440 volts.
Sludge punping equipment (2), 200 gpm; centrifugal,
open impeller; 15 HP; 1,060 rpm, 220/440 volts.
Aeration basins (3), 4 passes each 189' L x 30' W x
15' D. Net volume 1,002,000 cu.ft.; total blower
capacity of 79,500 cfm.
Secondary clarifiers (6) each 115' Dia x 11' SWD;
Total surface area 62,200 sq. ft.; peak overflow rate
of 1,095 gpd/sq.ft.
Return activated sludge pumps; two pumps with a design
capacity of 4200 gpm/19 ft TDH and two pumps rated at
10,000 gpm/23 ft TDH. Waste activated sludge pumps
(3); design capacity 1400 gpm/34 ft TDH.
Gravity thickeners (2); design capacity 65* Dia. x 10'
SWD; thickened sludge pumps (2), 600 gpm capacity.
Lime reaction tanks (6), 120' L x 120' W x 35' D.
Ferric chloride/alum feed system;
Storage tank (2), 8.8' Dia. x 30.6' L, capacity 9520
gals each; 4 feed pumps at 3.8 gpm. Polymer feed
system (lime reaction tank and gravity filters) (1) at
750 Ib/day and; primary feed tank (2) 5' Dia. x 4.5'
H, capacity of 1,000 gals.
Gravity Filters; Numbers of filters (8), peak flow
67.5 gpm; area/filter 900 sq.ft.; dual bed;
multi-media gravity flow.
Filter water clear well; Number of units (1); Total
capacity 450,000 gals; 94' L, 46' W, 17' D.
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Reaeration Tanks:
Mechanical surface aerators (2); 46' L x 46' W x 20'
SWD, Total volume of 84, 640 cu.ft.; capacity 170 Ib
02/nr at zero D.O.; size 50 HP/1770 rpm.
Chlorine contact tanks: multipass (2), 45' L x 62' W
x 15.9 SWD; Total volume of 84,000 cu.ft.
Hypochlorite storage tank: Bight (8), Sodium
hypochlorite; capacity of 18,000 gals.
2.0 PROPOSED PLANT MODIFICATIONS:
The plant's current capacity is 30 MGD. The plant is to be expanded to 40
M3D by the year 1995. COM has been awarded a contract to design
facilities to feed ferric chloride to the secondary system. This was done
in compliance with the new consent decree which requires more stringent
effluent limits for Phosphorus.
A study for odor problems at the plant was completed by James Montgomery
Engineers. The County is ready to spend $1,000,000 to provide plant
corrosion prevention.
The State Water Control Board issued a new NPDES permit in June, 1986
which requires toxicity monitoring.
3.0 PROPOSED RETROPITTIN3 FOR BIOLOGICAL NUTRIENT REMOVAL
The modification to retrofit the existing treatment plant for HLND and
LLND limits would require the addition of the Anaerobic and Anoxic Zones
prior to the Aeration zone. The plant currently uses tertiary filters and
thus the modification of the plant for AjO process would require the
additional secondary clarifiers to get an overall overflow rate of 600
gpd/sq ft. The land availability at the treatment plant is very limited
for any expansion and/or modification. Thus the LLND requirements which
requires a five (5) stage Bardenpho Process is not feasible.
Alternatively, to meet the LLND targets, the cost is presented by using a
three (3) stage A~0 process (HLND) followed by reactor clarification
with alum addition and deep bed denitrification filters.
The cost associated to meet both the levels of treatment are presented as
follows:
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HIGH LEVEL NUTRIENT DISCHARGE (TP - 2 mg/li TN - 8 mg/1)
INCREMENTAL CONSTRUCTION COST
TANKAGE REQUIREMENT SUMMARY FOR BLND RETROFIT
Tankage Raq'mt* Addl'n Surf. Land
Required Met by Tkg. Ar«« Area
Exist. Tk Reqd. Reqd. Available
1000 ou.ft.1000 eu.ft. sq. ft. sq. ft.
Anaerobic(IHr.) 223 0 223 14400
AnoxicdHr.) 223 0 223 1*400
A«roblc(6Hr.) 1337 1020 317 21000
Total 1783 1020 763 49800 114000
TANKAGE REQUIREMENTS:(16* WALL, 14" BASE SLAB AND 8" BAFFLES)
Anaerobic Anoxic Aerobic
Tankage Tankage Tankage
No. of Tanks 111
No. of passes/tank 444
Length pec pass (ft) 130 ISO ISO
Width per pass (ft) 24 24 35
Depth per pass (ft) 16 16 16
Total volume (cu.ft.) 230400 230400 336000
No. of baffles/tank 333
MIXER REQUIREMENTS:
Anaerobic Anoxic
Tankage Tankage
Volume of tanks (MG) 1.72 1.72
H.P. required (8 SO HP/MG) 86 86
No. of Mixers (10 HP/mixer) 9 9
No. of standby mixers 2 2
Total no. of mixers 11 11
No. of mixers existing 0 0
No. of mixers required 11 11
AERATION REQUIREMENTS (Appendix C-8)
Plant design flowrate (MG) 40.00
Plant Influent BOD (mg/1) 1S6.00
Aeration Influent BOD (mg/1) 104.00
Plant Effluent BOD (mg/1) 6.00
BOD loading (mg/1) 98
Ammonia loading (mg/1) 18
Oxygen required (Ibs/MG) 1S90
Air required (SCFM) 42662
Air required (SCFM) 160838
(8 peaking factor of 3.77)
Existing capacity (SCFM) 57600
Additional air required (SCFM) 103238
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CLARIFIERS REQUIREMENT:
To get over flow rate of 650 gpd/sq.ft;
Surface ar«» required: 61538 sq.ft.
Existing surface area available: 62200 sq.ft.
Additional surface area required: 0 sq.ft.
No. of clarlfler
Channels/tank
Diameter
Length
Width
Depth
PUMPING REQUIREMENT:
Existing Capacity Additional Capacity
Required
(Dgd) (gpa) (ngd) (gpm)
ARCY PUMPS <» 200XQ 00 80 55555
RAS PUMPS 9 73ZQ 27 18403 4 2431
COST CALCULATIONS:
TANKAGE CONCRETE COST:
Anaerobic Anoxle Aerobic
Tankage Tankage Tankage
Concrete volunea:
sldevalls (cu.yd.) 237 237 237
endwalls (cu.yd.) 152 152 221
base slab (cu.yd.) 665 665 958
Concrete vol./tank (cu.yd.) 1054 1054 1416
Vol. of baffles (cu.yd.) 178 178 178
Concrete Cost per tank 414395 414395 538380
(3 $342.50/cu.yd. for concrete)
$300.00/cu.yd. for baffles)
Total concrete cost ($) 414395 414395 538380
Total concrete cost for
additional tankage ($). 1367170
MIXER COST:
Anaerobic Anoxic
Tankage Tankage
Cost of mixer* ($) 132000 132000
(g $12,000 per mixer)
Installation cost ($) 26400 26400
(6 201 of mixer cost)
Installed mixer cost ($) 158400 158400
Total installed mixer cost ($) 316800
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PUMP COST: (ARCY, HAS AND PUMP BUILDING) No. of Unit Total
Pumps Cost($) Coat($)
ARCY POMP:
10,500 spm pumps each 8 15000 120000
HAS PUMP:
7,700 gpo pump each 1 26000 26000
Subtotal 9 146000
Installation(20X) 29200
Subtotal 175200
Puqi bulldinc(40' x 50')
g ($40/sq.ft.) 80000
Total cost ($) 255200
CLARIFIES TANKAGE CONCRETE COST:
Concrete volumes:
sidevalls (cu.yd.) 0
endvalls (cu.yd.) 0
base slab (cu. yd.) 0
Concrete volume (cu.yd.) 0
Concrete Cost
(• $342.50/cu.yd. fox concretei 0
Equlpaent cost 8 *OX 0
Installation « 20Z 0
Total cost for clarlfiers ($) • 0
BLOWERS & DIFFUSERS COST
COST CONTROL TOTAL
QTY. SCFM EACH($) PKC.($) COST($)
Blowers 6.00 20000 120000 2000 732000
Installation 8 20X 146400
Dlffusers
3 $30 per SCFM 3600000
Total Installed cost ($) • 4478400
ANAEROBIC DIGESTION SUPERNATANT SYSTEM COST:
Total cost ($) (Appendix C-15) 183463
ALUM FEED SYSTEM COST:
Total cost ($) (Appendix C-17) 110667
MISCELLANEOUS COST:
Pipe Tunnel- RAS + Recycle Pumping 2000000
TOTAL EQUIPMENT COST ($):
8711000
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INCREMENTAL O t M COST SUMMARY:
Maintenance and materials cost:
(3X of total construction)
Labor cost:( current plant budget - $3,537,000)
25X of existing budget is labor cost
Chemicals:
Includes Lime & Alum addition
682070
884250
146470
Power:
Mixers
Pumps:
ARC?
HAS
Blowers :
HP
172
600
100
5400
kW
129
449
75
4039
IcWHr/
YEAR
1101405
3834547
639091
34510925
Cost 8
$0.07/kWHr.
77098
268418
44736
2415765
Total power cost:
TOTAL O I M COST ($):
2806018
4518807
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LOW LEVEL NUTRIENT DISCHARGE (TP = 0.5 mg/ls IN - 3 mg/1)
INCREMENTAL CONSTRUCTION COST
TANKAGE REQUIREMENT SUMMARY FOR LLHD RETROFIT
Tankage Req'mts Addl'n Surf. Land
Required Met by Tkg. Area Area
Exist Tkg Reqd. Reqd. Available
lOOOcu.ft. lOOOcu.ftlOOOcu.ft. sq.ft. sq.ft.
AnMxobie(2Hr)
1st Anoxic(3Hr)
Aerobic (9Br)
2nd Anoxic(3Hr)
Rearation(lHr)
Total
446
668
2005
668
223
4010
0
0
1020
0
0
1020
446
668
98S
668
223
2990 175882 * 114000
* Based on an average tank depth of 17 ft.
From th« above table it is determined that due to the shortage of land
availability it will not be feasible to retrofit the 5 stage Bardanpho
process to meet the LLND limits.
Alternatively the LLHD limits can be achieved by retrofiting the
3 state A20 process vith alum addition and converting the existing
filters to deep bed denltrificatlon filters with methanel addition
facilities.
Total equipment cost for HLND ($) 8711000
Equipment cost for denltrifIcatlon filters ($) 3273000
TOTAL EQUIPMENT COST ($) : 11984000
* NOTE: The cost provided for the denltrification filters
is not site specific but based on a generic retrofit.
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TOTAL COST SUMMARY
INCREMENTAL CONSTRUCTION COST SUMMARY FOR ARLINGTON WWTP, X $1000
COST ITEM HLND LLND
Tankage requirements $ 1367 1367
Mixers $ 317 317
Clarifiers $ 0 0
Pumps-ARCY, RAS, Bldg. for pumps $ 255 255
Alum Feed $ 111 111
Supernatant System $ 183 183
Blowers & Duffusers $ 4478 4478
Eff. Filter-Pumps, Structure, Media $ 3273
Miscellaneous costs $ 2000 2000
SUBTOTAL 8711 11984
Non Component Cost (1) 5929 10839
TOTAL CONSTRUCTION 14640 22823
Eng. I Const. Supervision(19X) (2) 2782 4336
SUBTOTAL 17422 27159
Contingencies(20X) 3484 5432
Interest during construction(l/2PCI) 1829 2852
TOTAL CAPITAL COST 22736 35443 (3)
NOTES:
(1) Non-Component cost includes electrical. Instrumentation,
yard piping, site preparation & misc. work, and
retrofit-construction added cost.
(2) Engineering(10X), construction supervision(9X).
(3) This cost is not based on asite specific evaluation.
INCREMENTAL 0 t M COST SUMMARY
ITEM HLND LLND
Maintenance & Materials 682 1063
Labor 884 884
Chemicals 146 672
Power 2806 2829
SUBTOTAL 4518 5448
TOTAL ANNUAL COST(l) 6985 9294
NOTES:
(1) Total annual cost is 0 & M cost and annualized capital using
0.1085 capital recovery factor at 8.875 X interest rate.
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APPENDIX D-2
HOPEWELL WATER POLLUTION CONTROL PLANT
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TABLE OF CONTENTS
SECTICN PAGE
1.0 Description of Existing Facilities 1
2.0 Proposed Plant Modifications 9
3.0 Proposed Retrofiting for Biological
flj Nutrient Removal 9
4.0 Total Cost Summary 15
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APPENDIX D-2
HOPEWELL WATER POLLUTION CONTROL PLANT
1.0 DESCRIPTION OF EXISTING FACILITIES
The Hopewell Virginia Wastewater Treatment Plant (WWTP)
serves as a major domestic and industrial wastewater
treatment facility. Preliminary treatment consists of
bar screens and high rate grit chambers. The
wastewater is then subjected to primary clarification.
Secondary treatment is accomplished in a pure oxygen
activated sludge system with secondary clarification.
Wastewater is then discharged into the James River.
Sludgy from the primary clarifier goes to a gravity
thickener and to a sludge holding tank. Waste
activated sludge goes to an air flotation thickener and
a sludge holding tank. The combined thickened primary
and waste activated sludge is then sent for heat
treatment. The sludge is dewatered on vacuum filters
and the dewatered sludge cake is incinerated in an a
multiple hearth. The ash is taken to the City of
Hopewell landfill and the supernatant, filtrates and
scrubber water flows are returned to the head of the
primary clarifier. Figure D.2.1 presents the existing
process flow diagram for the Hopewell regional
wastewater treatment facility. Figure D.2.2 is the
site plan which depicts the land area available that
could be utilized to meet the additional tankage
requirements for HLND and LLND. Figure D.2.3 and D.2.4
are the proposed flow diagrams for HLND and LLND
processes.
The present design flow capacity for the plant is 50
MGD, with an average reported flow of 33 MGD in FY 86.
Table D.2.1 describes the average annual influent,
effluent characteristics and the current NPDES
requirements.
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TABLE D.2.1
HOPEWELL WWTP RAW SEWAGE, INFLUENT
AND EFFLUENT CHARACTERISTICS AND CURRENT NPDES
PERMIT REQUIREMENTS
(Yearly Average)
PARAMETER INFLUENT
BOD, rag/1 250
TSS, mg/1 200
pH 8.0-10.5
TP, mg/1
NH3, mg/1 25 - 55
TKN, mg/1 30-60
EFFLUENT NPDES PERMIT
25 9
40 16
6.1 - 7.0 6-9
0.5 NA
25 - 55 NA
30-60 NA
NA - Not Available
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The existing plant components and sizes are summarized
below:
Preliminary
Treatment; Screening Chambers
- Mechanical units (2); 3/8" x 2
"
spacing, 75 slope. Removes 5 cuft
of screening/MGD. Hydraulic capacity
= 35 MGD
Manual units (1); 1/4" x 2" bars @ 3"
spacing, 60 slope. Hydraulic
capacity » 35 MGD
Conveyors (3); 1 HP, 2 amp 24
hours/day. Grit chambers
3 channels each 8 feet W x 5'5" D x
65 feet L. Chain drives (3); 1 HP, 2
amp, 24 hours/day
Conveyor screws (2); 1 HP, 2 amp, 24
hours/day. Removal of 0.2 mm grit at
max flow of 70 MGD. Normal hydraulic
capacity/channel = 16.7 MGD.
Parshall Flume; 10 feet flume with
indicator, recorder and totalizer.
Capacity range 4 to 130 MGD.
Primary Treatment:
- Primary settling tanks (8), each 40
feet W x 200 feet L x 10 feet D.
Total volume of each tank = 598,400
gallons; Tank slope l/16"/foot toward
the sludge hopper.
- Sludge collection (8); longitudial and
cross collectors. Scrapers drive
driven by 0.75 HP 1.45 amp electric
motor.
- Primary sludge pumping station (2);
Gould, each rated at 600 gpm driven by
a 25 HP, 32 amp electric motor.
Secondary Treatment;
- Aeration basins (4) each 60 feet W x
240 feet L x 13.5 feet D; number of
trains = 4, 4 stages/train; each train
240 feet L x 60 feet x 13.5 feet D.
Volume - each stage = 360,000 gallons.
-1-
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Return activated sludge pumps (8),
sludge return rate - 37.93 MGD; waste
activated sludge pumps (8), rated at
5000 gpm each driven by 40 HP, 50
amps.
Recirculation pumps (6), rated at 1440
gpm.
Secondary setting tanks (8), each 40
feet W x 285 feet L x 14 feet D;
surface area 1140 sqft (each).
Normal hydraulic capacity 1 unit =
6.25 MGD.
Gravity Sludge Thickeners;
- Two each 95 feet in diameter, 10 feet
depth; hydraulic loading rate - 569
gpd/sqft; surface loading rate 7.5
Ib/d/sqft
Flotation Thickners:
- Three (3) each 42 feet L x 20 feet W x
13 feet D; surface area of each 797
sqft
Sludge Holding Tanks;
- Two (2); surface area 45 sqft; SWD of
24' each; storage capacity * 700,000
total gals.
Sludge Heating System;
- Heat exchangers (3); 900 gph capacity
each; temp. - 428 F
Vacuum Filters:
- Four (4) each 12 feet in diameter x 14
feet long. Filter surface area - 548
sqft each. Inclined belt, conveyors
(2).
Multiple Hearth Incinerator:
- One (1); furnace 22' 3" in diameter;
hearth (8); 2064 sqft effective
burning area.
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2.0 PROPOSED MODIFICATION
The plant has an average flow of 33 MGD and is designed
for 50 MGD. None of the effluent limits are met as per
the Virginia Department of Health inspection report.
Presently, nutrient discharge limitations are not
required by the plant. Toxicity testing on the
effluent has been requested by the State Water Control
Board for priority pollutant and non-priority pollutant
votatile organics. No major modifications to the plant
are planned.
3.0 PROPOSED RETROFITTING FOR BIOLOGICAL
NUTRIENT REMOVAL
The modification to retrofit the existing treatment
plant for HLND and LLND levels would require the
addition of anaerobic and anoxic zones prior to an
increased capacity of the aeration zone. The existing
covered pure oxygen aeration basin would be utilized
as part of the aeration requirements of the BNR
process design and additional tankage would be built.
Additional clarifiers would be provided to get an
overall overflow rate of 400 gpd/sqft and the required
pumps and mixers would be installed into the various
zones.
The plant currently has no problem in meeting the
phosphorus limits. In fact they are adding phosphorus
as a nutrient. The design of this plant calls only for
nitrification/denitrification and no addition of Alum
for phosphorus removal although alum addition
facilities will be provided. As the plant has existing
pure oxygen unox process, the additional tankage
required would also be built as covered aeration tanks.
The detention time required for such pure oxygen
system would be lower than normal activated sludge
basis and thus the detention time for aeration used
under pure oxygen system for A~0 process is
estalished as four (4) hours instead of six (6) hours.
Due to the shortage of land area availability,
retrofitting the five (5) stage Bardenpho Process will
not be feasible. In order to meet the LLND
requirements by BNR process, the proposal would include
the HLND (A20) process followed by a reactor
clarifier and denite filter with methanol addition.
The cost estimates for both the levels of treatment
i.e. the HLND and LLND are as follows:
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HIGH LEVEL NUTRIENT DISCHARGE (TP - 2 mg/1; TN - 8 mg/1)
INCREMENTAL CONSTRUCTION COST
TANKAGE REQUIREMENT SUMMARY FOR BLND RETROFIT
Tankage Req'mts Addl'n Surf. Land
Required ' Mat by Tkg. Arc* Area
Exist. Tk Reqd. Reqd. Available
1000 cu.ft.1000 cu.ft. sq. ft. sq. ft.
Anaerobic(IBr.) 278 0 278 20000
AnoxicUHr.) 278 0 278 20000
Aerobic(4Hr.) * 1115 778 337 23000
Total 1671 778 893 63000 65100
* Based on pure oxygen unox process
TANKAGE REQUIREMENTS: (16" WALL, 14" BASE SLAB AND 8* BAFFLES)
Anaerobic Anoxie Aerobic
Tankage Tankage Tankage
Ho. of Tanks 111
Bo. of passes/tank 444
Length per pass (ft) 100 100 115
Width per pass (ft) * 50 50 50
Depth per pass (ft) 15 15 15
Total volume (cu.ft.) 300000 300000 345000
No. of baffles/tank 333
MIXER REQUIREMENTS:
Anaerobic Anoxie
Tankage Tankage
Volume of tanks (MG) 2.24 2.24
H.P. required (9 50 HP/MG) 112 112
No. of Mixers (10 HP/mixer) 11 11
No. of standby mixers 2 2
Total no. of mixers 13 13
No. of mixers existing 0 0
No. of mixers required 13 13
AERATION REQUIREMENTS (Appendix C-8)
Plant design flowrate (MG) 50.00
Plant Influent BOD (mg/1) 250.00
Aeration Influent BOD (mg/1) 163.00
Plant Effluent BOD (mg/1) 25.00
BOD loading (mg/1) 138
Ammonia loading (mg/1) 50
Oxygen required (Ibs/MG) 3184.
Total oxygen required (Ib/day) 159211
Existing capacity (Ibs/day) 200000
Additional Oxygen required 0
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CLARIFIERS REQUIREMENT:
To get over flow rate of 400 gpd/sq.ft;
Surface area required: 125000 sq.ft.
Existing surface area available: 91200 sq.ft.
Additional surface area required: 33800 sq.ft.
No. of clarifier
Channels/tank
Diameter
Length
Width
Depth
1
3
n/a ft.
285
40
12 ft.
PUMPING REQUIREMENT:
Existing Capacity Additional Capacity
Required
(mgd) (gpm) (mgd) (gpm)
ARCY PUMPS 3 200ZQ 12 8640 88 61111
RAS PUMPS 3 75JEQ 38 26389 0 0
COST CALCULATIONS:
TANKAGE CONCRETE COST:
Anaerobic Anoxic Aerobic
Tankage Tankage Tankage
Concrete volumes:
sidevalls (cu.yd.) 148 148 170
endvalls (cu.yd.) 296 296 296
base slab (cu.yd.) 917 917 1049
top cover (cu.yd.) 0 0 1049
Concrete vol./tank (cu.yd.) 1361 1361 2564
Vol. of baffles (cu.yd.) Ill 111 128
Concrete Cost per tank 499443 499443 916570
(8 $342.50/cu.yd. for concrete)
$300.00/cu.yd. for baffles)
Total concrete cost ($) 499443 499443 916570
Total concrete cost for
additional tankage ($). 1915455
MIXER COST:
Anaerobic Anoxic
Tankage Tankage
Cost of mixers ($) 156000 156000
(8 $12,000 per mixer)
Installation cost ($) 31200 31200
(8 20X of mixer cost)
Installed mixer cost ($) 187200 187200
Total installed mixer cost ($) 374400
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PUMP COST: (ARCY, RAS AND PUMP BUILDING)
ARCY PUMP:
24,500 gpm pumps each
RAS POMP:
14,330 gpm pump each
Subtotal
Installation(20X)
Subtotal
Pump bulldin«(40f x 40')
9 ($40/sq.ft.)
Total Cost ($)
CLARIFIER TANKAGE CONCRETE COST:
Concr«t« volumes:
sldewalls (cu.yd.) 507
endwalls (cu.yd.) 107
base slab (cu. yd.) 1688
Concrete volume (cu.yd.) 2302
Concrete Cost
(8 $3*2.50/cu.yd. for concrete! 788435
Equipment cost 9 40X 315374
Installation 8 20Z 157687
Total cost for clariflers ($) 1261496
AERATOR COST
QTY. H.P.
Surface aerator 5.00 50
Installation 9 20X
Total installed cost ($)
ANAEROBIC DIGESTION SUPERNATANT SYSTEM COST:
Total cost ($) (Appendix C-15)
ALUM FEED SYSTEM COST:
Total cost ($) (Appendix C-17)
No. of Unit Total
Pumps Cost(S) Cost($)
3 55000 165000
0 44000 0
3 165000
33000
198000
64000
262000
COST CONTROL TOTAL
EACH(S) PKG.($) COST($)
20000 0 100000
20000
120000
193886
120000
TOTAL EQUIPMENT COST ($):
4246000
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INCREMENTAL 0 I M COST SUMMARY:
Maintenance and materials cost:
(3X of total construction)
Labor cost:( current plant budget « $5,500,000)
25Z of existing budget is labor cost
Chemicals:
Includes Lime t Alum addition
Power:
319746
1375000
184000
Mixers
Pumps:
ARCY
RAS
Aerators :
HP
260
450
0
250
kW
194
337
0
187
kWHr/
YEAR
1661637
2875910
0
1597728
Cost 9
$0.07/kWHr.
116315
201314
0
111841
Total power cost ($):
TOTAL O 4 M COST:
429469
2308215
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LOW LEVEL NUTRIENT DISCHARGE (IP =• 0.5 mg/1; TH - 3 mg/1)
INCREMENTAL CONSTRUCTION COST
TANKAGE REQUIREMENT SUMMARY FOR LLND. RETROFIT
An»«rob ie ( 2Hr )
1st Anoxlc(3Hr)
Aerobic(7Hr) *
2nd Anoxlc(3Hr)
Rearation(lHr)
Total
Tankage
Required
lOOOcu.ft.
557
836
1950
836
278
4457
Req'mts
Met by
Exist Tkg
lOOOou.ft
0
0
778
0
0
778
Addl'n
Tkg.
Reqd.
lOOOcu.ft.
557
836
1172
836
278
3679
Surf.
Area
Reqd.
sq.ft.
32765
49176
68941
49176
16353
216412
Land
Area
Available
sq . f t .
65100
Based on a pure oxygen unox process
* Based on an average depth of 17 ft.
From the above table it is determined that due to the shortage of Land
availability it will not be feasible to retrofit the 5 stage Bardenpho
process to meet the LLND limits.
Alternatively the, LLND limits can be achieved by retroflting the
3 stage A20 process with alum addition and converting the existing
filters to deep bed denitrification filters with methanol addition
facilities.
Total equipment cost for HLND ($) 4246000
Equipment cost for denltrificatioo filters ($) 4118000
TOTAL EQUIPMENT COST ($) : 8364000
* NOTE: The cost provided for the denitrification filters is not
site specific but based on a generic retrofit.
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TOTAL COST SUMMARY
INCREMENTAL CONSTRUCTION COST SUMMARY FOR HOPEWELL WWTP, X $1000
COST ITEM HLND LLND
Tankage requirements $ 1915 1915
Mixers $ 374 374
Clarifiers $ 1261 1261
Pumps-ARCY, RAS, Bldg. for pumps $ 262 262
Alum Feed $ 120 120
Supernatant System $ 194 194
Blowers, Diffusers, & Aerators $ 120 120
Eff. Filter-Pumps, Structure, Media $ 0 4118
SUBTOTAL 4246 8364
Non Component Cost (1) 2617 5500
TOTAL CONSTRUCTION 6863 13864
Eng. & Const. Supervlslon(19X) (2) 1304 2634
SUBTOTAL 8167 16498
Contingencies(20X) 1633 3300
Interest during construction(l/2PCI) 858 1732
TOTAL CAPITAL COST 10658 21530 (3)
NOTES:
(1) Non-Component cost includes electrical, instrumentation,
yard piping, site preparation t misc. work, and
retrofit-construction added cost.
(2) Englneering(lOZ), construction supervision(9X).
(3) This cost is noy based on a site specific evaluation
INCREMENTAL 0 i M COST SUMMARY
ITEM HLND LLND
Maintenance & Materials 320 646
Labor 1375 1450
Chemicals 184 877
Power 429 460
SUBTOTAL 2308 3433
TOTAL ANNUAL COST(l) 3464 5769
NOTES:
(1) Total annual cost is O & M cost and"annualized capital using
0.1085 capital recovery factor at 8.875 X interest rate.
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APPENDIX D-3
LOWER POTOMAC POLLUTION
CONTROL PLANT
-------
TABLE OF CONTENTS
SECTION PAGE
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1.0 Description of Existing Facilities 1
I 2.0 Proposed Plant Modifications 10
3.0 Proposed Retrofiting for Biological
• Nutrient Removal 11
4.0 Total Cost Suranary 20
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APPENDIX D-3
LOWER POTOMAC POLLUTION CONTROL PLANT
1.0 DESCRIPTION OF EXISTING FACILITIES
The original Lower Potomac Pollution Control Plant
(LPPCP) was expanded in the late 1970's from 18 MGD to
36 MGD by adding advanced waste treatment processes.
The current flows reaching the treatment plant are
domestic in nature. The wastewater treatment
facilities consist of mechanical screening, primary
sedimentation, aeration, and secondary sedimentation,
equalization, chemical phosphorus precipitation,
gravity filtration and chlorination.
Sludge from primary and secondary clarifiers is treated
by thickening, conditioning, dewatering and
incineration. The sludge from chemical tertiary
treatment is sent to a sanitary landfill.
Figure D.3.1 is a schematic of the existing plant
showing the main liquid stream unit processes as
designed. Figure D.3.2 is the layout of the existing
plant facilities. Figure D.3.3 and D.3.4 is a
schematic of the proposed treatment processes to meet
the HLND and LLND targets. Land area available for
expansion and/or retrofitting is included in the
planned expansion discussed later and site visits
indicate ample land area available for any expansion
and/or modification.
Average annual plant loading and effluent quality are
shown in Table D.3.1. As can be seen, the facility
achieves excellent BOD, TSS and phosphorous removal.
Its performance is poor for ammonia removal and does
not meet the NPDES. permit for TKN removal to <1 mg/1.
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Figure D.3.2
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TABLE D.3.1
LPPCP RAW SEWAGE AND EFFLUENT CHARACTERISTICS
(JUNE 1986 - JUNE 1987)
Parameter
Flow MOD
BOD-, mg/1
COD, mg/1
TSS , mg/1
Phosphorous , mg/1
pH
Temp., °c
Alkalinity, mg/1
Chloride, mg/1
TKN, mg/1
NH-j-N, mg/1
N02-N, mg/1
NO,-N, mg/1
Influent
33
175
377
218
7
9.2
21
172
57
36
19
0.50
0.74
Effluent
33
7
29
0.8
0.1
6-9
21°C
117
98
• 19
16
0.6
1.1
NPDES
Permit
36
10
—
10
0.18
6-9
—
—
—
1
—
—
—
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Major Existing Plant Components and Unit Sizes;
Liquid Processes
Raw wastewater retention
basin
Primary clarifiers
Aeration tanks
Aeration blowers
Secondary clarifiers
Secondary chlorination tanks
Equalization basins
Final and second stage
reactor clarifiers
1 basin; 5.7 MG effective
volume; 3 mechanically
cleaned bar screens at 55
MGD each
4 tanks; 139 ft x 45 ft x
10 ft SWD; 1080 gpd/sqft
and 1.7 hours detention
time at design flow
6 three-pass tanks with
each pass 182 ft x 30 ft
x 15 ft SWD; 7 MG net
volume; 4.8 hours
detention at design flow.
6 centrifugal
displacement units;
80,000 cfm total capacity
at 8 psig.
4-120 ft dia. tanks x
10.5 ft SWD; 800 gpd/sqft
and 2.4 hours detention
time.
4 - 145 ft dia. tanks X
16 ft SWD; 545 gpd/sqft
and 5.3 hours detention
time. .
2 tanks 70 ft x 61.5 ft x
8 ft SWD; 21 min.
detention at design flow
2 basins; 13.3 MG
effective volume;
mixer aerators.
12
4 tanks each 148 ft x 148
ft x 20 ft SWD; 822
gpd/sqft and 4.5 hours
detention at design flow
plus back wash return
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Multimedia filters
Monomedia
Reaeration tank
Post-chlorination tank
Solids Processes
Gravity thickeners
Flotation thickners
Sludge storage tanks
10 gravity filters, 30 ft
x 30 ft; 3.1 gpm/sqft at
design flow
8 gravity basins 34 ft x
34 ft; 5 ft carbon bed
depth; 3.1 gpm/sqft (8
basins at design flow);
down flow
1 tank 72 ft x 70.3 ft
22 ft SWD; 30 min.
detention at design flow
1 tank 72 ft x 72 ft x 20
ft SWD; 31 min. detention
at design flow
4-50 ft dia. tanks x 10
ft SWD (8 Ib/day/sqft
design loading-includes
pr i. and WAS)
3 tanks 40.2 ft x 12 ft x
12 ft SWD; 1.6 Ib/hr/sq
ft design loading
2-50 ft diameter tanks x
25 ft effective SWD;
total capacity 759,000
gals
Variable volume filter press 6 units,
Incineration
Lime sludge thickeners
4 multiple hearth
furnances; 2-6 hearth ^
units @ 25.75 ft dia; 2-7
hearth units @ 18.75 ft
dia; total installed
capacity 608 wet ton/day;
wet cake at 82% moisture
2 gravity units - 30 ft
dia x 20 ft SWD; 100
Ibs/day/sqft. lime design
loading
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Lime sludge centrifuges
Sludge incineration
3 solids-bowl units;
total installed mass lime
solids load 270 tons/day
2 multiple hearth units;
22-25 ft dia with 8
hearths; total installed
max lime capacity 400 dry
tons/day
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2.0 PROPOSED PLANT MODIFICATIONS
The wastewater treatment facility is currently under a
major expansion from its design flow capacity of 36 MGD
to 54 MGD. The expansion commenced in 1933 and is
projected to end in the middle of 1992. The expansion
is based on a non-nitrifying design but with provisions
to incorporate nitrification if required in the future.
Earlier modifications and in plant operation in the
early 1970's and required effluent standards had
resulted in certain equipment not being currently
operated or required. The current planned expansion
will therefore focus emphasis on potential utilization
of current surplus facilities such as the existing
activated carbon system, tertiary lime recalcination
system, recarbonation system and such other unit
processes that can be effectively utilized. The major
additions and/or modifications to be constructed as
part of the planned plant expansion are listed below:
- Addition of 1 screen building to the current
facility
- Addition of 2 flash mixing tanks
- Four additional primary settling tanks
- Two new additional aeration tanks
- Change all present positive displacement blowers
to centrifugal blowers and add one more blower
to meet the projected capacity.
- Addition of four new secondary clarifiers to the
present requirements
- Five new gravity filters with building (studies
are underway to modify the existing activated
carbon adsorption units to gravity filters)
- A new additional backwash storage tank
- A new additional dissolved air flotation unit
- Two additional new gravity sludge thickners
- A new sludge processing and sludge handling
facility
- Odor control equipment
-10-
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The total project cost for the proposed modifications
are estimated to be 100 million dollars as proposed by
Engineering Science(ES) of Fairfax, Virginia.
3.0 PROPOSED RETROFITTING FOR BIOLOGICAL
NUTRIENT REMOVAL
The proposed retrofit for BNR process to meet the HLND
and LLND limits would require additional tankage to
accommodate the anaerobic and anoxic zones for both
alternatives. The secondary clarifiers will be added
to obtain an overflow rate of 600 gpd/sqft as the plant
was existing tertiary filters. The retrofit details of
the two levels of treatment are presented as follows.
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HIGH LEVEL NUTRIENT DISCHARGE (TP • 2 mg/1; IN - 8 mg/1)
INCREMENTAL CONSTRUCTION COST
TANKAGE REQUIREMENT SUMMARY FOR BLNO RETROFIT
Tankage Req'nts Addl'n Surf. Land
R«qulr«d Mat by Tic*. Area Area
Exist. Tk Raqd. R«qd. Available
1000 cu.ft.1000 eu.ft. sq. ft. sq. ft.
Anaerobic(IHr.) 301 0 301 20320
AnoxicdHr.) 301 0 301 20520
Aerobic(6Hr.) 1805 983 822 54720
Total 2407 983 1424 95760 262800
TANKAGE REQUIREMENTS: (16* WALL, 14" BASE SLAB AND 8" BAFFLES)
Anaerobic Anoxic Aerobic
Tankage Tankage Tankage
No. of Tanks 224
Ho. of passes/tank 334
Length per pass (ft) 180 180 180
Width per pass (ft) 19 19 19
Depth per pass (ft) 15 15 16
Total volume (eu.ft.) 307800 307800 875520
No. of baffles/tank 223
MIXER REQUIREMENTS:
Anaerobic Anoxic
Tankage Tankage
Volume of tanks (MG) 2.30 2.30
H.P. required (8 50 HF/MG) 115 115
No. of Mixers (10 HP/mixer) 12 12
No. of standby mixers 3 3
Total no. of mixers 15 15
No. of mixers existing -*3 0 0
No. of mixers required 15 15
AERATION REQUIREMENTS (Appendix C-8)
Plant design flovrate (MG) 54
Plant Influent BOD (mg/1) 200
Aeration Influent BOD (mg/1) 130
Plant Effluent BOD (mg/1) 7
BOD loading (mg/1) 123
Anmonla loading (mg/1) 19
Oxygen required (Ibs/MG) 1857
Air required (SCFM) 67294
Air required (SCFM) 168235
(8 peaking factor of 2.5)
Existing capacity (SCFM) 80000
Additional air required (SCFM) 88235
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CLARiyiERS REQUIREMENT:
To get over flow rate of 600 gpd/sq.ft;
Surface area required:
Existing surface area available:
Additional surface area required:
90000 sq.ft.
45239 sq.ft.
44761 sq.ft.
Ho. of clarifier
Channels/tank
Diameter
Length
Width
Depth
4
n/a
120 ft.
n/a
n/a
II ft.
PUMPING REQUIREMENT:
Existing Capacity Additional Capacity
Required
(ogd) (gpo) (mgd) (gpm)
ARCT POMPS g 200XQ 0 0 108 75000
RAS PUMPS 8 75WJ 10 6944 31 21528
COST CALCULATIONS:
TANKAGE CONCRETE COST:
Anaerobic Anoxic Aerobic
Tankage Tankage Tankage
Concrete volumes:
sldevalls (cu.yd.) 267 267 284
endwalls (cu.yd.) 84 84 120
base slab (cu.yd.) 485 485 636
Concrete vol./tank (cu.yd.) 836 836 1040
Vol. of baffles (cu.yd.) 133 133 213
Concrete Cost per tank 326230 326230 420100
(8 $342.50/cu.yd. for concrete;
$300.00/cu.yd. for baffles)
Total concrete cost ($) 652460 652460 1680400
Total concrete cost for
additional tankage ($). 2985320
MIXER COST:
Anaerobic Anoxic
Tankage Tankage
Cost of mixers ($) 180000 180000
(8 $12,000 per mixer)
Installation cost ($) 36000 36000
(8 20Z of mixer cost)
Installed mixer cost ($) 216000 216000
Total installed mixer cost ($) 432000
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PUMP COST: (ARCY, HAS AND PUMP BUILDING) No. of Unit Total
Pumps Cost ($) Cost ($)
ARCY PUMP:
24,500 gpm pumps each 5 55000 275000
RAS PUMP:
14,350 gpm pump each 3 44000 132000
Subtotal 8 407000
Installatlon(20X) 81400
Subtotal 488400
Pump building(30' x 40')
3 ($40/sq.£t.) 48000
Total ($) 536400
CLARIFIER TANKAGE CONCRETE COST:
Concrete volumes:
sidewalls (cu.yd.) 1249
endwalls (cu.yd.) 0
base slab (cu. yd.) 2088
Concrete volume (cu.yd.) 3337
Concrete Cost
(C $342.50/cu.yd. for concrete; 1142923
Equipment coat 9 40X 457169
Installation 3 20Z 228585
Total cost for clarlflers ($) 1828676
BLOWERS & DIFFUSERS COST
COST CONTROL TOTAL
QTY. SCFM EACH PKG.($) COST ($)
Blowers 5 20000 120000 2000 610000
Installation 3 20% 122000
Diff users
8 $30 per SCFM 3000000
Total installed coat ($) 3732000
ANAEROBIC DIGESTION SUPERNATANT SYSTEM COST:
Total cost ($) (Appendix C-15) 226351
ALUM FEED SYSTEM COST:
Total cost ($) (Appendix C-17) 129600
TOTAL EQUIPMENT COST (S):
9870000
-14-
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INCREMENTAL O t M COST SUMMARY:
Maintenance and materials cost:
(3Z of total construction)
Labor cost:( current plant budget « $5,666,124)
25% of existing budget is labor cost
Chemicals:
Includes Lime t Alum addition
Power:
Total power cost ($):
TOTAL 0 t M COST ($):
-15-
757268
1416531
197730
Mixers
Pumps:
ARCY
HAS
Blowers :
HP
230
750
450
4500
kU
172
561
337
3366
kWHr/
YEAR
1469910
4793184
2875910
28759104
Cose 8
S0.07/kWHr.
102894
335523
201314
2013137
2652868
5024397
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LOW LEVEL NUTRIENT DISCHARGE (TP - 0.5 mg/1: TN - 3 mg/1)
INCREMENTAL CONSTRUCTION COST
TANKAGE REQUIREMENT SUMMARY FOR LLNO RETROFIT
Tankage
Required
lOOOcu.ft.
Anaerobic(2Hr) 602
1st Anoxic(3Hr) 902
Aerobic(9Hr) 2707
2nd Anoxic (3Hr) 902
Rearation(lHr) 301
Total 5414
Req'mts
Met by
Exist Tkg
Addl'n
Tkg.
Reqd.
lOOOcu. f tlOOOeu. f t .
0
0
983
0
0
983
TANKAGE REQUIREMENTS: (16" WALL, 14" BASE
No. of Tanks
No. of passes /tank
Length par pass (ft.)
Width par pass (ft.)
Depth par pass (ft.)
Total voluma (cu.ft.)
No. of baff las /tank
MIXER REQUIREMENTS:
Volume of tanks (MG)
H.P. raqulrad (9 50 HP/MG)
No. of Mixers (10 HP/mixer)'
No. of standby mixers
Total no. of mixers
No. of mixers existing
No. of mixers required
Anaerobic
Tankage
2
3
240
24
18
622080
2
Anaerobic
Tankage
4.65
233
24
5
29
0
29
602
902
1724
902
301
4431
SLAB AND
1st
Anoxic
Tankage
2
4
240
28
17
913920
3
1 st
Anoxic
Tankage
6.75
338
34
7
41
0
41
Surf.
Area
Reqd.
sq.ft.
34560
53760
103680
53760
19000
264760
Land
Area
Available
sq.ft.
262800
8* BAFFLES)
Aerobic
Tankage
4
4
240
27
17
1762560
5
2 nd
Anoxic
Tankage
6.75
338
34
7
41
0
41
2nd
Anoxic
Tankage
2
4
240
28
17
913920
3
Reaeration
Tankage
2
2
190
25
' 17
323000
1
AERATION REQUIREMENTS (Appendix C-8)
Plant design flovrate (MG)
Plant Influent BOD (mg/1)
Aeration Influent BOD (mg/1)
Plant Effluent BOD (mg/1)
BOD loading (mg/1)
Ammonia loading (mg/1)
Oxygen required (Ibs/MG)
Air required (SCFM)
Air required (SCFM)
(@ peaking factor o£ 2.5)
Existing capacity (SCFM)
Additional air required (SCFM)
54
200
130
7
123
19
2062
8441S
211044
80000
131044
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CLARIFIERS REQUIREMENT:
To get over flow rat* of 600 gpd/sq.ft:
Surface »r«» required:
Existing surface area available:
Additional surface area required:
90000 sq.ft.
45239 sq.ft.
44761 sq.ft.
No. of clarlfler
Channels/tank
Diameter
Length
Width
Depth
n/a
120 ft.
n/a
n/a
11 ft.
PUMPING REQUIREMENT:
Existing capacity (MG) Additional capacity
Required
(mgd) (gpm) (mgd) (gpm)
ARCY PUMPS 8 400X 0 0 216 149999
RAS PUMPS 3 100X Q 10 6944 44 30555
COST CALCULATIONS:
TANKAGE CONCRETE COST:
1st 2nd
Anaerobic Anoxlc Aerobic Anoxlc Reaeratlon
Tankage Tankage Tankage Tankage Tankage
Concrete volumes:
sldewalls (cu.yd.) 427 403 403 403 319
endwalls (cu.yd.)- 128 188 181 188 84
base slab (cu.yd.) 801 1223 1181 1223 453
Concrete vol./tank (cu.yd.) 1356 1814 1765 1814 856
Vol. of baffles (cu.yd.) 213 302 504 302 80
Concrete Cost per tank 528330 711895 755713 711895 317180
(8 $342.50/eu.yd. for concrete;
$300.00/cu.yd. for baffles)
Total concrete cost ($) 1056660 1423790 3022850 1423790 634360
Total concrete cost for
additional tankage ($). 7561450
MIXER COST:
1st 2 nd
Anaerobic Anoxlc Anoxlc
Tankage Tankage Tankage
Cost of mixers ($)
(8 $12,000 per mixer) 348000 492000 492000
Installation cost ($)
(Q 20Z of mixer cost) 69600 98400 98400
Installed mixer cost ($) 417600 590400 590400
Total Installed mixer cost ($) 1598400
-17-
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PUMP COST: (ARCY, RAS AND PUMP BUILDING)
No. of Total
Pumps Cost ($) Cost ($)
ARCY POMP:
24,500 gpm pump each 8 55000 440000
RAS PUMP:
14,350 gpm pump each 3 44000 132000
Subtotal 11 572000
Installatlon(20X) 114400
Subtotal 686400
Pump building (30' x 90')
(8 $40/sq. ft.) 108000
Total Cost ($) 794400
CLARIFIER TANKAGE CONCRETE COST:
Generate volumes:
sldewalls (cu.yd.) 1249
endvalls (cu.yd.) 0
bas« slab (cu. yd.) 2088
Concrete volume (cu.yd.) 3337
Concrete Cost
(g $342.50/cu.yd. for concrete) 1142923
Equipment cost 8 40Z 457169
Installation % 20X 228585
Total cost for clarLflers ($) 1828676
BLOWERS & DIFFUSERS COST
COST CONTROL TOTAL
QTY. SCFM EACH ($) PKG.($) COST ($)
Blowers 7 20000 120000 0 340000
Installation 3 20X 168000
DIFFUSERS
3 $30 per SCFM 131044 3931321
Total Installed cost ($) 4939321
ANAEROBIC DIGESTION SUPERNATANT SYSTEM COST
Total cost ($) (Appendix C-1S) 226351
ALUM FEED SYSTEM COST
Total cost ($) (Appendix C-17) 149400
TOTAL EQUIPMENT COST ($):
17096526
-18-
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INCREMENTAL 0 i M COST SUMMARY:
Maintenance and materials coat
(3X of total construction) $ 1302861
Labor cost:( current plant budget - $5,446,000)
25X of existing budget is labor cost $ 1361500
Chemicals:
Includes Lime & Alum addition $ 526590
Power:
kWHr/ Cost 8
HP kW YEAR $0.07/kWHr.
Mixers 901 674 5758212 403075
ARCY 1200 898 7669094 536837
RAS 450 337 2875910 201314
Blowers: 6300 4712 40262746 2818392
Total Power Cost ($): 3959617
TOTAL 0 4 M COST ($): 7150568
-19-
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TOTAL COST SUMMARY
INCREMENTAL CONSTRUCTION COST SUMMARY FOR LPPCP WWTP, X $1000
COST ITEM HLHD LLNO
Tankage requirements $ 2985 7561
Mixers $ 432 1598
Clariflers $ 1829 1829
Pumps-ARCY, RAS, BLdg. for pumps $ 536 794
Alum Feed $ 130 149
Supernatant System $ 226 226
Blowers & Duffusers $ 3732 4939
Eff. Filter-Pumps, Structure, Media $
SUBTOTAL 9870 17097
Non Component Cost (1) 6384 10869
TOTAL CONSTRUCTION 16254 27965
Eng. & Const. Supervlston(19X) (2) 3088 5313
SUBTOTAL 19343 33279
Contingencles(20X) 3869 6656
Interest during constructlon(l/2PCI) 2031 3494
TOTAL CAPITAL COST 25242 43429
NOTES:
(1) Non-Component cost Includes electrical. Instrumentation,
yard piping, site preparation I misc. work, and
retrofit-construction added cost.
(2) Bnglneerlng(lOX), construction supervlslon(9X).
INCREMENTAL 0 & M COST SUMMARY
ITEM HLND LLND
Maintenance & Materials 757 1303
Labor 1417 1362
Chemicals 198 527.
Power 2653 3960
SUBTOTAL 5025 7152
TOTAL ANNUAL COST(l) 7764 11864
NOTES:
(1) Total annual cost Is 0 I M cost and annualIxed capital using
0.1085 capital recovery factor at 8.875 X Interest rate.
-20-
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BALTIMORE PATAPSCO
WASTEWATER TREATMENT PLANT
I
I APPENDIX D-4
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TABLE OF UUNT.EN'.LS
SECTION PAGE
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1.0 Description of Existing Facilities 1
• 2.0 Proposed Plant Modifications 6
3.0 Proposed Retrofiting for Biological
• Nutrient Removal 6
4.0 Total Oast Summary 15
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APPENDIX D-4
BALTIMORE PATAPSCO WASTEWATER TREATMENT PLANT
1.0 DESCRIPTION OF EXISTING FACILITIES
The existing Patapsco Wastewater Treatment Plant is a
secondary treatment facility design to treat flow up to
70 MGD. The treatment facility consists of mechanically
cleaned bar screens and grit removal facility as
pretreatment; primary sedimentation, aeration secondary
sedimentation as secondary treatment; chlorination as
final liquid treatment before its discharge to Patapsco
River.
The aeration basin has a pure oxygen unox generation
process for the supply of air. Sludge from primary and
secondary clarifiers are blended and polymer is added to
it before it goes through the filter, plate and frame
presses and then is later incinerated.
Figure D.4.1 is a schematic of the existing plant
showing the main wet processes and sludge treatment and
handling facilities. Figure D.4.2 and D.4.3 are the
proposed flow diagrams to meet the High Level Nutrient
Discharge (HLND) and Low Level Nutrient Discharge (LLND)
limits. Plant loadings and effluent characteristics are
shown in Table D.4.1. As can be seen the facility
achieves excellent BOD, TSS and phosphorus removal.
Presently, the facility does not have any effluent
nitrogen limitations.
Major plant conponent and unit size are:
Bar screens and grit removal
Primary settling tanks:
Activated sludge aeration basins:
Secondary clarifiers:
Gravity settling tanks:
Sludge Blending tanks:
Air flotation thickners;
-1-
3 8 69 ft W x 195 ft
L x 12.75 ft D, 17.5
MG, 9.71 ft SWD.
4 cells, 4 reactors,
each 71.5 ft W x 71.5
ft L x 12.5 ft SWD,
7.6 M gals.
4, each 210 ft dia. x
16 ft SWD.
65 ft dia.
SWD.
x 10 ft
2, 70 ft inside dia.
x 60.5 ft D.
4, 41.8 ft L x 12 ft
W x 13.11 ft D.
-------
UJ
UJ
d
CD
Z
I-H
i-
en
•"*
x
CO
LU
DC
CD
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LU
LU
OC
DC CL
CD LU
LU
3 I—
o cn
a o
LU CJ
CD CO
O 0.
a_ <
a K-
GC <
a_ a.
ru
LU
cr
ID
CD
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s
8 «
Ml
u.
I
LU
LU
OC
CE QC
CD LU
LU
3 I—
O CO
Q O
LU U
CO CO
o a.
a. <
o i—
^ ^
Q_ CL
n
LU
CE
Z)
CD
-4-
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TABLE D.4.1
PATAPSCO WWTP RAW SEWAGE
AND EFFLUENT CHARACTERISTICS
Parameter
Flow, MGD
TSS, mg/1
BOD, mg/1
COD, mg/1
TP, mg/1
TN, mg/1
pH
NH4, mg/1
Influent
38.9
288
246
485
4.7*
N/A
N/A
15.6*
Effluent
38.9
25
20
111
2.2
15.3
6.5
NPDES Permit
70
30
30
—
2.0
—
6.5
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• (JUNE, 1986 TO AUGUST, 1987 AVERAGE)
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_ N/A = not available
• * - September 1, 1987 to October 5, 1987
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2.0 PROPOSED PLANT MODIFICATIONS
The plant is currently under expansion to increase its
primary clarification capacity.
3.0 PROPOSED RETROFITTING
Modifications of the existing Patapsco WWTP to meet the
HLND and LLND requirements would require the addition
of anaerobic, anoxic and aerobic (covered tankage for
pure oxygen unox process) as per the design criteria
for A~0 and the Bardenpho process. The plant does
not have any tertiary filters and thus additional
clarifiers will have to be built to achieve an overflow
rate of 400 gpd/sq ft. Chemical addition system will
be built for phosphorus reduction. The BNR retrofit
for both the levels of treatment is presented as
follows.
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HIGH LEVEL NUTRIENT DISCHARGE (TP - 2 mg/1; TN - 8 mg/1)
INCREMENTAL CONSTRUCTION COST
TANKAGE REQUIREMENT SUMMARY FOR HLND RETROFIT
Tankage Req'mts Addl'n Surf. Land
Required Met by Tk(. Area Area
Exist. Tk Reqd. Reqd. Available
1000 cu.ft.1000 ou.ft. sq. ft. aq. ft.
AnaarobicUHr.) 390 0 390 26050
AnoxicdHr.) 390 0 390 26050
Aerobic(4Hr.) * 1560 1022 538 35912
Total 2340 1022 1318 88012
* Based on pure oxygen unox process
TANKAGE REQUIREMENTS: (16" WALL, 14" BASE SLAB AND 8" BAFFLES)
Anaerobic Anoxic Aerobic
Tankage Tankage Tankage
No. of Tanks 112
Ho. of passes/tank 444
Length per pass (ft) 81 81 67
Width per pass (ft) 81 81 67
Depth per pass (ft) 17 17 17
Total volume (cu.ft.) 442849 442849 610504
No. of baffles/tank 333
MIXER REQUIREMENTS:
Anaerobic Anoxic
Tankage Tankage
Volume of tanks (MG) 3.31 3.31
H.P. required (8 50 HP/MG) 166 166
No. of Mixers (10 HP/nixer) 17 17
No. of standby mixers .' 3 3
Total no. of mixer* 20 20
No. of mixers existing 0 0
No. of mixers required 20 20
AERATION REQUIREMENTS (Appendix C-8)
Plant design flovrate (MG) 70.00
Plant Influent BOD (mg/1) 246.00
Aeration Influent BOD (mg/1) 202.00
Plant Effluent BOD (mg/1) 20.00
BOD loading (mg/1) 182
Ammonia loading (mg/1) 16
Oxygen required (Ibs/MG) 2283
Total oxygen required (Ib/day) 159844
Existing capacity (Ibs/day) 320000
Additional Oxygen required 0
-7-
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CLARIFIERS REQUIREMENT:
To get ov«r flow rate of 400 gpd/sq.ft;
Surf»c« area required: 175000 sq.ft.
Existing surface area available: 138544 sq.ft.
Additional surface area required: 36456 sq.ft.
No. of clarlfler
Channels/tank
Diameter
Length
Width
Depth
3
n/a
125 ft.
n/a
n/a
14 ft.
PUMPING REQUIREMENT:
Existing Capacity Additional Capacity
Required
(ogd) (gpo) (mgd) (gpm)
ARCY PUMPS 8 200XQ 0 0 140 97222
RAS PUMPS 3 75XQ 29 19792 24 16667
COST CALCULATIONS:
TANKAGE CONCRETE COST:
Anaerobic Anoxic Aerobic
Tankage Tankage Tankage
Concrete volumes:
sidewalls (cu.yd.) 135 135 112 *
endwalls (cu.yd.) 542 542 450
base slab (cu.yd.) 1196 1196 834
top cover (cu.yd.) 0 0 834
Concrete vol./tank (cu.yd.) 1873 1873 2230
Vol. of baffles (cu.yd.) 102 102 84
Concrete Cost per tank 672103 672103 788975
«J $342.50/eu.yd. for concrete;
$300.00/cu.yd. for baffles)
Total concrete cost ($) 672103 672103 1577950
Total concrete cost for
additional tankage ($). 2922155
MIXER COST:
Anaerobic Anoxic
Tankage Tankage
Cost of mixers ($) 240000 240000
(8 $12,000 per mixer)
Installation cost ($) 48000 48000
(9 201 of mixer cost)
Installed mixer cost ($) 288000 288000
Total Installed mixer cost ($) 576000
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PUMP COST: (ARCY, HAS AND PUMP BUILDING) No. of Unit Total
Pumps Cost(S) Cost($)
ARCY PUMP:
24,500 gpm pumps each 6 55000 330000
HAS PUMP:
14,350 gpm pump «»ch 2 44000 88000
Subtotal 8 418000
Installation 20X) 83600
Subtotal 501600
Pump building(40' z 40')
« ($40/sq.ft.) 64000
Total Cost ($) 565600
CLARIFIBR TANKAGE CONCRETE COST:
Concrete voluows:
sldewalls (cu.yd.) ' 1242
endvalls (cu.yd.) N/A
base slab
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INCREMENTAL 0 & M COST SUMMARY:
Maintenance and materials cost:
(3X of total construction)
Labor cost:( current plant budget - $5,806,964)
25X of existing budget is labor cost
Chemicals:
Includes Lime & Alum addition
473586
1451741
256317
Power:
HP
331
900
300
350
kW
248
673
224
kWHr/
YEAR
cost e
$0.07/kWHr.
Mixers
Pumps:
ARCY
RAS
Aerators:
Total power cost ($):
2116998 148190
5751821
1917274
402627
134209
262 2236819 156577
841604
TOTAL 0 (. M COST:
3023248
-io-
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LOW LEVEL NUTRIENT DISCHARGE (IP - 0.5 mg/ls IN - 3 mg/1)
INCREMENTAL CONSTRUCTION COST
TANKAGE REQUIREMENT SUMMARY FOR LLND RETROFIT
Tankage Req'mts
Required Met by
Exist Tkg
lOOOcu.ft. lOOOcu.ft
Anaerobic (2Hr) 780 0
1st Anoxic <3Hr) 1170 0
Aerobic(7Hr) * 2729 1022
2nd Anoxic(3Hr) 1170 0
Rearatlon(lHr) 390 0
Total 6239 1022
* Based on a pure oxygen unox process
TANKAGE REQUIREMENTS: (16" WALL, 14" BASE
Anaerobic
Tankage
Ho. of Tanks 2
No. of passes/tank 4
Length per pass (ft.)* 81
Width per pass (ft.) 81
Depth per pass (ft.) 17
Total volume (cu.ft.) 385699
No. of baffles /tank 3
MIXER REQUIREMENTS:
Anaerobic
Tankage
Volume of tanks (MG) 6.63
H.P. required (8 50 HP/MG) 331
No. of Mixers (10 BP /mixer) 33
No. of standby mixers 7
Total no. of mixers 40
No. of mixers existing 0
No. of mixers required 40
AERATION REQUIREMENTS (Appendix C-8)
Plant design flowrate (MG)
Plant Influent BOD (mg/1)
Aeration Influent BOD (mg/1)
Plant Effluent BOD (mg/1)
BOD loading (mg/1)
Ammonia loading (mg/1)
Oxygen required (Ibs/MG)
Total oxygen required (Ibs/day)
Existing capacity (Ibs/day)
Additional oxygen required
Addl'n
Tkg.
Reqd.
lOOOcu.ft.
780
1170
1707
1170
390
5217
SLAB AND 8*
1st Anoxic
Tankage
3
4
81
81
17
1328548
3
1st Anoxic
Tankage
9.94
497
50
10
60
0
60
70
246
202
20
182
16
2587
181095
320000
0
Surf.
Area
Reqd.
sq.ft.
52100
78150
115600
78150
26050
350050
BAFFLES)
Aerobic
Tankage
4
4
85
85
17
1965200
3
2nd Anoxic
Tankage
9.94
497
50
10
60
0
60
Land
Area
Available
sq.ft.
2nd Anoxic
Tankage
3
4
81
81
17
1328548
3
"
Re aeration
Tankage
1
4
81
81
17
442849
3
Additional air required (SCFM) *
* For final reaeration.
11730
-11-
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CLARIFIERS REQUIREMENT:
To get ov«r flow rate of 400 gpd/sq.ft;
Surface area required:
Existing surface area available:
Additional surface area required:
No. of clarifler 3
Channels /tank n/a
Diameter 125 ft.
Length n/a
Width n/a
Depth 14 ft.
PUMPING REQUIREMENT:
Existing capacity (MB)
(mgd) (gpm)
ARCY PUMPS 9 400X 0 0
RAS PUMPS Q 100Z Q 29 19792
COST CALCULATIONS:
TANKAG3 CONCRETE COST:
Anaerobic
Tankage
Concrete volumes:
sldevalls (cu.yd.) 135
endvalls (cu.yd.) 542
base slab (cu.yd.) 1196
top cover (cu.yd.) Q
Concrete vol. /tank (cu.yd.) 1873
Vol. of baffles (cu.yd.) 102
Concrete Cost per tank 672103
(9 $342.50/cu.yd. for concrete;
$300.00/cu.yd. for baffles)
Total concrete cost ($) 1344205
Total concrete cost for
additional tankage ($).
MIXER COST:
Anaerobic
Tankage
Cost of mixers ($)
(8 $12,000 per mixer) 480000
Installation cost ($)
«! 20X of mixer cost) 96000
Installed mixer cost ($) 576000
Total installed mixer cost ($)
175000 sq.ft.
138544 sq.ft.
36456 sq.ft.
Additional capacity
Required
(mgd) (gpm)
280 194443
42 '28819
1st 2nd
Anoxic Aerobic ' Anoxic Reaeration
Tankage Tankage Tankage Tankage
135 143 135 135
542 571 542 542
1196 1323 1196 1196
0 1323 0 0
1873 3360 1873 1373
102 107 102 102
672103 1182900 672103 672103
2016308 4731600 2016308 672103
10780523
1st 2 nd
Anoxic Anoxic
Tankage Tankage
720000 720000
144000 144000
864000 864000
2304000
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PUMP COST: (ARCY, HAS AND PUMP BUILDING)
No. of Unit Total
Pumps Cost($) Cost($)
ARCY PUMP:
72,000 gpo pump each . 4 100000 400000
HAS PUMP:
14,350 gpo pump each 3 44000 132000
Subtotal 7 532000
Inst*Uatlon(2QX) 106400
Subtotal 638400
Pump bulldlnc(40' X 60')
(« $40/sq. ft.) 48000
Total Cost ($) 686400
CLARIFIER TANKAGE CONCRETE COST:
Concrete volumes:
sldevalls (cu.yd.) 1242
endwalls (cu.yd.) 0
base slab (cu. yd.) 1695
Concrete volume (cu.yd.) 2937
Concrete Cost
(C $342.50/eu.yd. for concrete; 1005923
Equipment cost 9 40Z 402369
Installation 9 20* 201185
Total cost for clarlflers ($) 1609476
BLOWERS, DIFFUSERS, & AERATORS COST
COST CONTROL TOTAL
QTY. SCTM EACH(S) PKG.($) COST($)
Blowers 4 3000 24000 0 96000
Installation 8 20Z 19200
DIFFUSERS
9 $30 per SCFM 360000
-W
AERATORS 18 50 B.P. 20000 0 360000
Installation 8 20Z 72000
Total Installed cost ($) 907200
ANAEROBIC DIGESTION SUPERNATANT SYSTEM COST
Total cost ($) (Appendix C-15) 271441
ALUM FEED SYSTEM COST
Total cost ($) (Appendix C-17) 193667
TOTAL EQUIPMENT COST ($):
16751666
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INCREMENTAL 0 & M COST SUMMARY:
Maintenance and materials coat
(32 of total construction) $ 1258282
Labor cost:( current plant budget « $5,806,964)
25Z of existing budget is labor cost $ 1451741
Chemicals:
Includes Lime & Alum addition $ 682617
Power:
HP
1325
600
1200
1500
kW
991
449
898
1122
IcWHr/
YEAR
Cost 8
$0.07/kWBr.
Mixers
Pumps:
ARCY
RAS
Blowers/Aerators:
Total Power Cost ($):
8467991
3834547
7669094
9586368
592759
268418
536837
671046
2069060
TOTAL 0 & M COST ($):
5461700
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TOTAL COST SUMMARY
INCREMENTAL CONSTRUCTION COST SUMMARY FOR PATAPSCO WWTP, X $1000
COST ITEM HLND LLND
Tankage requirements $ 2922 10781
Mixers $ 576 2304
Clarlfiers $ 1609 1609
Pumps-ARCY, RAS, Bldg. for pumps $ 566 686
Alum Feed $ 168 194
Supernatant System $ 271 271
Blowers, Diffusars, & Aerators $ 168 907
Eff. Filter-Pumps, Structure, Media $ 0 0
SUBTOTAL 6280 16752
Non Component Cost (1) 3885 10257
TOTAL CONSTRUCTION 10165 27008
Eng. & Const. Supervision(19Z) (2) 1931 5132
SUBTOTAL 12097 32140
Conting«ncies(20X) 2419 6428
Interest during constructlon(l/2PCI) 1270 3375
TOTAL CAPITAL COST 15786 41943
NOTES:
(1) Non-Component cost includes electrical, instrumentation,
yard piping, site preparation & misc. work, and
retrofit-construction added cost.
(2) EngineeringdOX), construction supervision(9X).
INCREMENTAL 0 & M COST SUMMARY
ITEM HLND LLND
Maintenance & Materials 474 1258
Labor 1452 1452
Chemicals 256 683
Power 842 2069
SUBTOTAL 3024 5462
TOTAL ANNUAL COST(l) 4737 10013
NOTES:
(1) Total annual cost is 0 & M cost and annualized capital using
0.1085 capital recovery factor at 8.875 X Interest rate.
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APPENDIX D-5
ALEXANDRIA POLLUTION
CONTROL PLANT
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TABIE OF CONTENTS
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• SECTION PAGE
1.0 Description of Existing Facilities 1
I 2.0 Proposed Plant Modifications 9
3.0 Proposed Retrofiting for Biological
• Nutrient Removal 9
4.0 Total Cost Summary 16
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APPENDIX D-5
ALEXANDRIA SANITATION AUTHORITY WWTP
1.0 DESCRIPTION OF EXISTING FACILITIES
The existing Alexandria WWTP was built in 1975-1984 as
a biological/physical-chemical plant designed to treat
54 MGD of flow. The plant is designed with chemical
addition (alum or ferric) to the primary clarifiers for
suspended solids and BOD5 removal. Secondary
treatment is accomplished with rotating biological
contactors and intermediate clarifiers. Carbon towers
are installed but not in use following the intermediate
clarifiers. Intermediate clarifier effluent has alum
added before flowing through secondary settling tanks
for phosphorous removal. Final setting tank effluent
is then filtered with dual media filters, chlorinated
and then aerated before discharge to Hunting Creek.
Sludge from the primary, intermediate and secondary
settling tanks is pumped to gravity thickeners where it
is thickened to 4.5 - 5% solids. Thickened sludge is
anerobically digested, dewatered with centrifuges and
hauled to the EPA composting operation at a nearby.
landfill. Composted sludge is mixed with lime and held
for two (2) hours and then hauled as agricultural land
application.
Figure D.5.1 is a schematic of the existing plant
showing the main wet process units. Figure D.5.2 is a
layout of the Alexandria plant site. Figure D.5.3 and
D.2.4 are the proposed flow diagram for HLND and LLND
targets. As can be seen, the present treatment plant
site is confined on all four sides. To the north lies
a cemetery, to the west and east are developed areas,
while to the south is the 1-495 ftteltway. Land area
available for plant expansion and/or modifications are
limited to the area just south of the mixed media
filters and the area beneath the Virginia Electric
Power Company's (VEPCO) high voltage power lines.
The 1986 average annual plant loadings and effluent
quality are shown in Table D.5.1. As can be seen the
facility achieves excellent BOD-, TSS and Phosphorus
removal, but no nitrogen removal.
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04
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CD
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a.
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TABLE D.5.1
ALEXANDRIA WWTP RAW SEWAGE CHARACTERISTICS
AND EFFLUENT (1986 ANNUAL AVERAGE)
Parameter
BOD5
TSS
Total P
TKN
NH3-N
FLOW
NA = Not
Influent
152 mg/1
165 mg/1
5.5 mg/1
>20 mg/1
NA
35 MGD
Available
Prim. Eff.
46
(30 soluble)
NA
NA
NA
NA
NA
Effluent
12
2
0.06
20.3
19.3
NPDES
PERMIT
18
13 ( summer )
13
0.18
54
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Major plant unit size and design criteria are as
follows:
Raw Sewage Pumps
Capacity (mgd) 156
TDH (ft) 42
Primary Clarifiers
Total Area (sqft) 49,760
Total Volume (cuft) 448,000
Design overflow rate (gpd/sqft) 1,080
Design detention time (hr) 1.5
Design BOD,, removal (with alum)-% 65
Rotating biological Contractors -
(56 units)
Total disc surface area (sqft) 5,348,000
Design loading (gpd/sqft) 10.0
Design BOD5 removal (%) 63
Design tanK volume (cuft) 112,000
(approx. 15,000 gal/disc)
Tank dimensions (approx.) 25* wide
14' long
7' deep
Intermediate Settling Tanks
Total area (sqft) 92,800
Length (ft) 145
Width (ft) 80
Sidewater depth (ft) 11
Total volume (cuft) 1,020,000
Intermediate Pumps
Capacity (mgd) 120
• TDH (ft) 52
Secondary Settling Tanks
Total area (sqft) 59,800
• Length (ft) 40
• Width (ft) 40
Sidewater depth (ft) 11
I Total volume (cuft) 657,800
Design overflow rate (gpd/sqft) 800
Dual Media Filters
Design loading rate (gpm/sqft 3.9
Phosphorous removal (%) 60
Influent phosphorous (mq/J.) 0.5
Effluent phosphorous (mg/D 0.2
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Gravity Thickening Tanks for Primary
Intermediate Clarifier Sludge (2 each)
Total surface area (sqft) 6,400
SWD (ft) 10
Total volume (cuft) 85,600
Tank diameter (ft) 45
Design loading rate:
Total flow both sludges (mgd) 5.08
Overflow rate (gpd/sqft) (1) 800
Total solids (Ibs/day) 93,000
% solids 8
Design thickened sludge volume (gal) 138,000
(1) includes 0.64 MGD plant effluent
Gravity Thickening Tanks for Final
Clarifier Sludge, (2 each)
Total surface area (sqft) 4,760
SWD (ft) 10
Total volume (cuft) 63,900
Tank diameter (ft) 55
Design loading rate:
Sludge flow (mgd) 0.80
Overflow rate (gpd/sqft) (2) 400
Solids loading (Ibs/day) 6,200
Thickened solids cone. (%) . 2
Thickened sludge volume (gpd) 124,000
(2) Including additional 765 gpm of
plant effluent
Sludge Digestion Tanks
(2 each)
Diameter (ft) 75
•SWD (ft) 27.75
Total volume (cuft) 450,000
% VSS destruction (%) 57
Original Final Settling Tanks
(Estimated size)
200 ft x 130 ft x 11 ft deep
Volume (cuft) 286,000
Post Aeration
(mechanical aerators)
Installed units (8 each)
Total capacity (Ibs 02/day) 26,000
Firm capacity (Ibs/day) 22,800
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2.0 PROPOSED PLANT MODIFICATIONS
The Alexandria plant was designed with provisions that
future permit limits would require the plant to meet a
1.0 mg/1 limit for unoxidized ammonia. Preliminary
studies have been completed to size these units to meet
a 2 mg/1 NH3~N effluent limit. Studies have also
been conducted to determine disposition of plant
sludge. The present use of composted sludge as a
landfill cover is only temporary in nature. Due to
odors from the composted sludge, agricultural disposal
of the composted sludge is not feasible. Studies have
been completed which have evaluated two sludge disposal
options. These are:
(1) Installation of additional digester capacity and
lime stabilization to further stabilize the
sludge to eliminate odors from the composted
sludge (present VSS destruction is less than 50%
compared to a design value of 56%). This
additional capacity would approximately double
the existing digester volume.
(2) Installation of sludge pelletization equipment
and disposal of the pelletized sludge
agriculturally. Installation of pelletizing
equipment would eliminate the need to install
new digester capacity and a lime stabilization
system.'
3.0 PROPOSED RETROFITTING FOR
BIOLOGICAL NUTRIENT REMOVAL
Modification of the existing Alexandria WWTP to meet
LLND and HLND limits will require elimination of the
existing biological rotating contractors and
installation of activated sludge systems. In order to
keep BOD-/T-P ratios as high as possible, chemical
addition to the primary clarifier will be eliminated
and the intermediate clarifiers and rotating biological
contactor (RBC) tanks will be converted into the
required anaerobic, anoxic and aeration tanks.
The plant has existing tertiary filters and would thus
require the addition of secondary clarifiers to obtain an
overflow rate (OFR) of 600 gpd/sq. ft. Land area available
for this and the blower and pump building can be
accommodated within the plant.
-9-
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For the LLND requirements, the entire land area available
in addition to using the existing tankage does not
accommodate the eighteen (18) hours detention time required
by the Bardenpho Process.
However, the LLND targets can be accomplished by
retrofitting the A2
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HIGH LEVEL NUTRIENT DISCHARGE (TP = 2 mg/1; TN = 8 rag/I)
INCREMENTAL CONSTRUCTION COST
TANKAGE REQUIREMENT SUMMARY FOR HLND RETROFIT
Tankage Req'mts Addl'n Surf. Land
Required Met by Tkg. Area Area
Exist. Tk Reqd. Reqd. Available
1000 cu.ft.1000 cu.ft. sq. ft. sq. ft.
Anaerobic(IHr.) 301 301 0 0
AnoxlcdHr.) 301 301 0 0
Aerobic(6Hr.) 1805 420 1385 96000
Total 2407 1022 1385 96000 130691
TANKAGE REQUIREMENTS: (16" WALL, 14" BASE SLAB AND 8" BAFFLES)
Anaerobic Anoxic Aerobic
Tankage Tankage Tankage
No. of Tanks 004
Ho. of passes/tank 004
Length per pass (ft) 0 0 240
Width per pass (ft) 0 0 25
Depth 'per pass (ft) 0 0 15
Total volume (cu.ft.) 0 0 1440000
No. of baffles/tank 003
MIXER REQUIREMENTS:
Anaerobic Anoxic
Tankage Tankage
Volume of tanks (MG) 2.25 2.25
H.P. required (8 50 HP/MG) 113 113
No. of Mixers (10 HP/mixer) 11 11
No. of standby mixers 2 2
Total no. of mixers 14 14
No. of mixers existing 0 0
No. of mixers existing 14 14
AERATION REQUIREMENTS (Appendix C-8)
Plant design flowrate (MG) 54
Plant Influent BOD (mg/1) 152
Aeration Influent BOD (mg/1) 114
Plant Effluent BOD (mg/1) 12
BOD loading (mg/1) 102
Ammonia loading (mg/1) 19
Oxygen required (Ibs/MG) 1665
Air required (SCFM) 60314
Air required (SCFM) 132691
(@ peaking factor of 2.2)
Existing capacity (SCFM) 0
Additional air required (SCFM) 132691
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CLARIFIERS REQUIREMENT:
To get over flow race of 600 gpd/sq.ft:
Surface area required: 90000 sq.ft.
Existing surface area available: 84000 sq.ft.
Additional surface area required: 6000 sq.ft.
No. of clarifier
Channels/tank
Diameter
Length
Width
Depth
1
2
n/a
160
19
11
PUMPING REQUIREMENT:
Existing Capacity Additional Capacity
Required
(ragd) (gpm) (mgd) (gpm)
ARCY PUMPS 3 200ZQ 0 0 108 75000
RAS PUMPS 8 75XQ 3 2083 38 26042
COST CALCULATIONS:
TANKAGE CONCRETE COST:
Anaerobic Anoxic Aerobic
Tankage Tankage Tankage
Concrete volumes:
sidewalls (cu.yd.) 0 0 356
endvalls (cu.yd.) 0 0 148
base slab (cu.yd.) 0 0 1096
Concrete vol. /tank (cu.yd.) 0 0 1600
Vol. of baffles (cu.yd.) 0 0 267
Concrete Cost per tank 0 0 628100
(8 S342.50/cu.yd. for concrete;
$300.00/cu.yd. for baffles)
Total concrete cost (S) 0 0 2512400
Total concrete cost for
additional tankage (S). 2512400
MIXER COST:
Anaerobic Anoxic
Tankage Tankage
Cost of mixers ($) 168000 168000
(8 $12,000 per mixer)
Installation cost ($) 33600 33600
(8 20X of mixer cost)
Installed mixer cost ($) 201600 201600
Total installed mixer cost ($) 403200
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PUMP COST: (ARCY, RAS AND PUMP BUILDING) No. of Unit Total
Pumps Cost(S) Coat($)
ARCY PUMP:
24,500 gpm pumps each 3 55000 165000
RAS PUMP:
12,600 gpm pump each 4 44000 176000
Subtotal 7 341000
Installatlon<20X) 68200
Subtotal 409200
Pump building(30' x 40')
<» ($40/sq.£t.) 48000
Total cost ($) 457200
CLARIFIER TANKAGE CONCRETE COST:
Concrete volumes:
sldevalls (cu.yd.) 261
endwalls (cu.yd.) 41
base slab (cu. yd.) 263
Concrete volume (cu.yd.) 565
Concrete Cost
(8 $342.50/cu.yd. for concrete; 193513
Equipment cost 9 40Z 77405
Installation 9 20X 38703
Total cost for clarifiers 309620
BLOWERS & DIFFUSERS COST
COST CONTROL TOTAL
QTY. SCFM EACH($) PKG.($) COST($)
Blowers 7 20000 120000 2000 854000
Installation 8 20Z 170800
Diffusers
@ $30 per SCFM 4200000
Total installed cost ($) 5224800
ANAEROBIC DIGESTION SUPERNATANT SYSTEM COST:
Total cost ($) (Appendix C-15) 226351
ALUM FEED SYSTEM COST:
Total cost ($) (Appendix C-17) 129600
MISCELLANEOUS COSTS:
Intermediate lift station + Foundation,piles etc. ($) 5248000
TOTAL EQUIPMENT COST ($):
14511000
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INCREMENTAL 0 4 M COST SUMMARY:
Maintenance and materials cost:
(3X of total construction)
Labor cost:( current plant budget «• $4,645,400)
25X of existing budget is labor cost.
Chemicals:
Includes Lime & Alum addition
1085354
1161350
197730
Power:
Mixers
Pumps :
ARCY
RAS
Blowers :
HP
225
450
600
6300
kW
168
337
449
4712
kWHr/
YEAR
1437955
2875910
3834547
40262746
Cost 8
$0.07/kWHr.
100657
201314
268418
2818392
Total power cost ($):
3388781
TOTAL 0 4 M COST ($) :
5833215
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LOW LEVEL NUTRIENT DISCHARGE (TP = 0.5 mg/1; TN = 3 rag/I)
INCREMENTAL CONSTRUCTION COST
TANKAGE REQUIREMENT SUMMARY FOR LLND RETROFIT
Anaerobic (2Hr)
1st Anoxic(3Hr)
Aerobic (9Hr)
2nd Anoxic(3Hr)
Rearat ion ( IHr )
Total
Tankage
Required
lOOOcu.fc.
602
902
2707
902
301
5414
Req'tnts Addl'n
Met by Tkg.
Exist Tkg Reqd.
'1000cu.ftlOOOcu.ft.
602
420
0
0
0
1022
0
482
2707
902
301
4392
Surf.
Area
Reqd.
sq.ft.
—
—
--
—
—
292800 *
Land
Area
Available
sq.ft.
130691
* Based on an average tank depth of 15 ft.
From the above table it is determined that due to the shortage of land
availability it will not be feasible to retrofit the 5 stage Bardenpho
process to meet the LLND limits.
Alternatively the LLND limits can be achieved by retrofitting the
3 stage A20 process with alum addition and converting the existing
filters to deep bed denitrlficatlon filters with methanol addition
facilities.
Total equipment cost for HLND ($)
Equipment cost for Denitrification Filters ($)
TOTAL EQUIPMENT COST ($):
14511000
4160000
18671000
* NOTE: The cost provided for the denitrlficatlon filters is not
site specific but based on a generic retrofit.
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TOTAL COST SUMMARY
INCREMENTAL CONSTRUCTION COST SUMMARY FOR ALEXANDRIA WWTP, X $1000
COST ITEM HLND LLND
Tankage requirements $ 2512 2512
Mixers $ A03 403
Clarifiers $ 310 310
Pumps-ARCY, RAS, Bldg. for pumps $ 457 457
Alum Feed $ . 130 130
Supernatant System $ 226 226
Blowers & Duffusers $ 5225 5225
Eff. Filter-Pumps, Structure, Media $ - 4160
Miscelleneous Costs $ 5248 5248
SUBTOTAL 14511 18671
Non Component Cost (1) 8786 15026
TOTAL CONSTRUCTION 23297 33697
Eng. & Const. Supervision(19X) (2) 4426 6402
SUBTOTAL 27723 40099
Contingencies(20X) 5545 3020
Interest during construction(l/2PCI) 2911 4210
TOTAL CAPITAL COST 36178 52329 (3)
NOTES:
(1) Non-Component cost includes electrical, instrumentation,
yard piping, site preparation I misc. work, and
retrofit-construction added cost.
(2) Engineering(lOX), construction supervision(9X).
(3) This cost is not based on a site specific evaluation.
INCREMENTAL 0 I M COST SUMMARY
ITEM HLND LLND
Maintenance & Materials 1085 1570
Labor 1161 1161
Chemicals "l98 907
Power 3389 3412
SUBTOTAL 5833 7050
TOTAL ANNUAL COST(l) 9758 12728
NOTES:
(1) Total annual cost is 0 ( M cost and annualIzed capital using
0.1085 capital recovery factor at 8.875 X Interest rate.
-16-
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APPENDIX D-6
RICHMOND SEWAGE
TREATMENT PLANT
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TABLE OF CONTENTS
SECTION PAGE
1.0 Description of Existing Facilities l
2.0 Proposed Plant Modifications 10
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3.0 Proposed Retrofiting for Biological
Nutrient Removal 12
• 4.0 Total Cost Summary 21
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APPENDIX D-6
RICHMOND SEWAGE TREATMENT PLANT
1.0 DESCRIPTION OF EXISTING FACILITY
The existing Richmond, Virginia WWTP is designed to
treat 70 MGD of combined dry weather and stormwater
flow, the majority of which is domestic in origin.
Preliminary treatment includes primary and secondary
screens and grit removal facilities. Secondary
treatment consists of primary sedimentation tanks
followed by activated sludge aeration basins and
secondary sedimentation tanks. The wastewater flow is
then conveyed to the final chlorine contact tank before
its discharge to the outfall structure to the James
River.
Sludge processes includes sludge thickening tanks which
receive sludge from primary and secondary clarifiers.
The sludge from the thickening tanks is subjected to
anaerobic digestion and elutriation. Sludge is
dewatered using filter presses and is then put on
sludge drying beds for additional drying before its
final disposal.
Figure D.6.1 is a schematic of the existing plant
showing the liquid and sludge treatment facilities.
Figure D.6.2 is the layout of the existing facility at
the Richmond WWTP. Figure D.6.3 and D.6.4 are the
proposed flow schematic to meet High Level Nutrient
Discharge (HLND) and Low Level Nutrient Discharge
(LLND) targets.
From Figure D.6.2 it can be seen that the present
treatment plant is confined on the east and west sides.
Land area available for expansion is limited to the
north and south sides of the treatment plant.
Average annual plant loadings and effluent quality are
shown in Table D.6.1. As can be seen the facility
achieves excellent BOD5 and TSS removals.
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UIM
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MIL
uiB
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FIGURE 4-1
K
til
Q
Z
o
UI
Z
ui
CO
Z
Q
I*
> tu
UJ UJ
cc
O
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a
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LU
DC
LU
H-
LU
I—
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<
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CO
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D_
GC
CD
a
LU
ac
ID
CD
feSS
M S. at
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TABLE D.6.1
RICHMOND WWTP RAW SEWAGE
AND EFFLUENT CHARACTERISTICS
Parameter
BOD5, mg/1 (1)
TSS, mg/1 (1)
TP, mg/1 (2)
Flow, MGD (1)
pH (2)
Fecal
Coliform, No./lOOO ml (1)
NH3-N, mg/1 (2)
N02-N, mg/1 (2)
N03-N, mg/1 (2)
TP, mg/1 (3)
Residual
Chlorine, mg/1 (1)
Influent
135
164
8
74
7
N/A
14
0.02
0.05
—
Effluent
12
8
5
74
7
19
14
0.66
1.27
2.99
NPDES Permit
8
10
N/A
80
6-9
200
N/A
N/A
N/A
2.0
4.0
(1) Obtained from DMR reports from Aug '86 to Aug '87
(2) Obtained from Monthly operations report.
(3) New requirements by State by year 1989.
N/A - not available
-6-
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Existing plant component size and design criteria are presented as
follows;
Bar Screens
Number of units
Width of channel
Max. depth of flow
Clear bar spacing
Max. velocity of flow thru
screen
Type
Disposal of screenings
Grit Chambers
Number of Channels
Length of Channel
Width of Channel
Controlled velocity
Min. depth of flow
Max. depth of flow
Method of cleaning
Capacity of Grit Chamber
4
5 ft.
6.6 ft.
3/4 inch
3.6 ft/sec
mechanically back cleaned
container hauled to
landfills
Grit Chamber tl
4
70 ft.
12 ft.
0.6 to 1.0 ft/sec
5.2 ft.
7.5 ft.
mechanical
326 MGD
Grit Chamber »2
4
75 ft.
12 ft.
0.6 to 1.0 ft/sec
4.7 ft.
11.7 ft.
clamshell bucket
202 M3D
Main Raw Sewage Pumps
Pump No.
TDH
Capacity
ft.
Capacity
MX
1
2
3
4
35
35
35
35
40
75
75
75
Primary Sedimentation Tanks
Number of Tanks
Number of Bays/tank
Width of Bay
Length of Tanks
Avg. Water Depth
Total Tank Volume
Total Surface Area
Weir Overflow Rate
4
4
20 ft.
230 ft.
11.5 ft.
846,000 cu ft
73 r 600 sq ft
47,700 gals/day/ft of weir
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Aeration Tanks
Number of Tanks 4
Length of Tanks 240 ft
Number of passes/tank 4 ft
Width of Passes 27 ft
Average water depth . 15 ft
Total tank volume 11.08 million gals
Final Sedimentation Tanks
Number of tanks 6
Number of bays/tank 4
Width of bays 17.5 ft
Length of tanks 200 ft
Total tank area 84,000 sq ft
Avg water depth 11.0 ft
Total tank volume 6.91 mil. gal
Surface loading rate 836 gal/sq ft/day
Tertiary Filters
No. of filters 2
Length of tank 75' L
Width of tank 10* W -
Depth of tank 5' D ,
Loading rate 2.58 gpn/ft § 50.2 M3D
Filter media coarse media 2-3 MM particles
Chlorine Contact Tank
Size of tank (2 passes) 455 ft x 63 ft
Tank volume 195,000 cu ft
No. of evaporation and chlorination system 3
Capacity (each) ^ 8,000 Ibs/day
-8-
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Air Blowers and Diffusers
Number of units
Rated capacity
Type
Number of diffusers/pass
Number of diffusers/tank
21,500 cfm at 7.5 psig
sparge
196
784
Primary Sludge and Scum to Digester
Number of Pumps
Rated Capacity
TDH at Rated Capacity
Primary Sludge to Thickener
Number of Pumps
Rated Capacity
TDH at Rated Capacity
2
220 gpm
70 ft.
5 (1 standby)
3850 gpm
13 ft.
Return Sludge Pumps
Number of Pumps
Rated Capacity
TDH at Rated Capacity
2
1050 gpm
36 ft.
Sludge Thickening Tanks
Number of Tanks
Dia. of Tanks
Total Tank Area
Side Water Depth
Total Tank Volume
4
55 ft
9,500 sq ft
9 ft
107,000 cu ft
Thickened Sludge Pumps
Number of Units
Rated Capacity
TDH at rated capacity
8
80 gpm
125 ft
-9-
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Sludge Digester Tanks
Gas Holder Cover
Fixed Cover Separate Tank
of tanks 3 1
Dia. of tank 95 to 96 ft 95 ft
Side water depth 27.75 ft 27.75 ft
Volume 225,700 cu ft 224,650 cu ft
Estimated destruction of volatile solids - 52.5%
Elutriation Tanks
Number of tanks 2
Length x width 185 x 35 ft
Surface area/ tank 6,460 sq ft
Volume/tank 0.58 M3D
Vacuum Filters
Number of filters 6
Size of each unit 12 ft x 16 ft
Filter area/unit 2,412 sq ft
2.0 PROPOSED PLANT MODIFICATIONS:
The Richmond Wastewater Treatment Plant serves the City of Richmond, VA
Henrico County, and parts of Chesterfield and Goochland Counties.
Regional plans for wastewater treatment in the Richmond area have
determined that Henrico, Hanover and Goochland flows will be removed from
the Richmond plant service area and conveyed for treatment to a new plant
located on the James River below Richmond at Deep Bottom. As a result of
this, the revised NPDES permit and pending Consent Decree does not require
the Richmond WWTP to meet final effluent limits until December 31, 1990 at
which time the Henrico plant at Deep Bottom is expected to be in
operation. The permit also required the City to make improvements to its
existing wastewater treatment facilities along with certain wet weather
and Shockoe system flows until the new Henrico, WWT facilities are
operational in order to maintain interim limits of effluent quality.
The improvements at the plant necessary to maintain these interim limits of
effluent quality are planned to be operational by mid-1988 and additional
facilities to meet final effluent limits by July 1, 1989.
-10-
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The total project cost for the recommended plant inprovements is
approximately 43 million dollars.
The following major improvements ware recommended:
- Replace existing engines and electric motors
with new and adjustable frequency drives.
- Add coagulant and automatic coagulant storage
feed facilities.
- Relocate recycle flows/modify vaste sludge
systems.
- fldd new sludge thickener facility for WAS
thickening.
- Replace existing gravity thickener sludge punps.
- A3d new polymer storage and feed systems for
gravity and centrifuge sludge thickening.
- Convert sludge separation tank to digester No. 6
and modify sludge feed, withdrawal and heating
systems.
- Convert the elutriation tank to sludge holding
tanks including mixing equipment.
- Replace vacuum filters with centrifuges.
- Perform all essential instrumentation and
control improvements, and provide a new
microprocessor-based data management system.
- Provide sludge grinding for primary, waste
activated and digested sludge.
- Convert manual chlorine feed to automatic
flow-paced feed system.
- Aid new effluent filter facility.
-11-
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3.0 PROPOSED RETROFITTING FOR BNR REMOVAL
Modification of the existing Richmond WWTP to meet the
High level Nutrient Discharge (HLND) would require the
addition of the anaerobic and anoxic zoness prior to the
aeration zone. Additional tankage will have to be
built for the requirements for the anaerobic, anoxic
and aeration zone as required in the A20 Process.
The construction of tertiary filters is already
underway. Thus the addition of secondary clarifiers
will be necessary to get an overflow rate of 600
gpd/ft . Plant visits indicated that the additional
tankage required to meet the HLND limits could be
accommodated at the three (3) sides of the existing
aeration basin where some additional space is
available. The BNR process is designed for a peak flow
of 91 MGD. This takes into consideration of the
Henrico County Sanitary flows. Aeration requirements
are based on the individual BOD and NH.
concentration. A peaking factor of 2.2 was established
to design additional aeration requirements and is based
on extreme average peak daily flows and loading rates.
To meet the Low Level Nutrient Discharge (LLND) limits,
the five (5) stage Bardenpho process would require
additional tankage. This additional tankage is
proposed to be accommodated besides the existing
areation basins. Recycle and RAS pumps would also be
required as per design criteria for the Bardenpho
Process. Tertiary filters and chemical additidn
systems are already under construction and are designed
by Greeley and Hansen.
The costs associated with each category of discharge
limits are as follows:
-12-
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HIGH LEVEL NUTRIENT DISCHARGE (TP - 2 mg/L; TN =• S mg/1)
INCREMENTAL CONSTRUCTION COST
TANKAGE REQUIREMENT SUMMARY FOR HLND RETROFIT
Tankage Req'mts Addl'n Surf. Land
Required Met by Tkg. Area Aram
Exist. Tk Raqd. Reqd. Available
1000 cu.ft.1000 cu.ft. aq. ft. sq. ft.
Anaerobic(IHr.) 507 0 507 33600
AnoxicUHr.) 507 0 507 33600
Aerobic(6Hr.) 3041 1483 1558 104400
Total 4014 1483 2572 171600 821900
TANKAGE REQUIREMENTS: (16" WALL, 14" BASE SLAB AND 6" BAFFLES)
Anaerobic Anoxic Aerobic
Tankage Tankage Tankage
No. of Tanks 113
No. of passes/tank 555
Length per pass (ft) 240 240 240
Width per pass (ft) 28 28 29
Depth per pass (ft) 17 17 17
Total volume (cu.ft.) . 571200 571200 1774800
No. of baffles/tank 444
MIXER REQUIREMENTS:
Anaerobic Anoxic
Tankage Tankage
Volume of tanks (MG) 4.27 4.27
H.P. required (8 50 HP/MG) 214 214
No. of Mixers (10 HP/mixer) 21 21
No. of standby mixers 4 4
Total no. of mixers 26 26
No. of mixers existing 0 0
No. of mixers required 26 26
AERATION REQUIREMENTS (Appendix C-8)
Plant design flowrate (MG) 91.00
Plant Influent BOD (mg/1) 135.00
Aeration Influent BOD (mg/1) 88.00
Plant Effluent BOD (mg/1) 12.00
BOD loading (mg/1) 76
Ammonia loading (mg/1) 18
Oxygen required (Ibs/MG) 1388
Air required (SCFM) 84734
Air required (SCFM) 186415
(9 peaking factor of 2.2)
Existing capacity (SCFM) 79500
Additional air required (SCFM) 106915
-13-
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CLARIFIERS REQUIREMENT:
To gat over flow rate of 600 gpd/sq.ft;
Surface area required: 151667 sq.ft.
Existing surface area available: 84000 sq.ft.
Additional surface area required: 67667 sq.ft.
No. of clarifier
Channels/tank
Diameter
Length
Width
Depth
4
5
n/a
200 ft.
17 ft.
14 ft.
PUMPING REQUIREMENT.:
Existing Capacity Additional Capacity
Required
(mgd) (spm) (mgd) (gpm)
ARCY PUMPS <» 200 ZQ 0 0 182 126388
HAS PUMPS 8 75ZQ 3 2083 65 45312
COST CALCULATIONS:
TANKAGE CONCRETE COST:
Anaerobic Anoxic Aerobic
Tankage Tankage Tankage
Concrete volumes:
sidewalls (cu.yd.) 403 403 403
endwalls (cu.yd.) 235 235 243
base slab (cu.yd.) 1518 1518 1571
Concrete vol./tank (cu.yd.) 2156 2156 2217
Vol. of baffles (cu.yd.) 403 403 403
Concrete Cost per tank 859330 859330 880223
(9 $342.50/cu.yd. for concrete:
$300.00/cu.yd. for baffles)
Total concrete cost ($) 859330 859330 2640668
Total concrete cost for
additional tankage ($). 4359328
MIXER COST:
Anaerobic Anoxic
Tankage Tankage
Cost of mixers (S) 312000 312000
(8 $12,000 per mixer)
Installation cost ($) 62400 62400
(8 20Z of mixer cost)
Installed mixer cost ($) 374400 374400
Total installed mixer cost ($) 748800
-14-
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PUMP COST: (ARCY, RAS AND PUMP BUILDING) No. of Unit Total
Pumps Cost (S) Cost ($)
ARCT PUMP:
24,500 gpm pumps each 8 55000 440000
RAS PUMP:
14,350 gpm pump each 5 44000 220000
Subtotal 13 660000
Installation(20Z) 132000
Subtotal 792000
Pump building(40' x 80')
8 ($40/sq.ft.) 128000
Total Cost ($) 920000
CLARIFIER TANKAGE CONCRETE COST:
Concrete volumes:
sidewalls (cu.yd.) 3319
endwalls (cu.yd.) 470
base slab (cu. yd.) 3138
Concrete volume (cu.yd.) 6927
Concrete Cost
(8 $342.50/cu.yd. for concrete) 2372498
Equipment cost 13 4OX 948999
Installation 8 20X ' 474500
Total cost for clarlflers ($) 3795996
BLOWERS t. DIFFUSERS COST
COST CONTROL TOTAL
QTY. SCFM EACH ($) PKG.($) COST ($)
Blowers 6.00 20000 120000 2000 732000
Installation 3 20Z 146400
Dlffusers
8 $30 per SCFM 3600000
Total Installed cost ($) 4478400
ANAEROBIC DIGESTION SUPERNATANT SYSTEM COST:
Total cost ($) (Appendix C-15) 326163
ALUM FEED SYSTEM COST:
Total cost ($) (Appendix C-17) 218160
TOTAL EQUIPMENT COST ($):
14846000
-15-
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INCREMENTAL 0 4 M COST SUMMARY:
Maintenance and materials cost:
(3Z of total construction)
Labor cost:( current plant budget - $4,645,400)
25X of existing budget is labor cost
Chemicals:
Includes Lime I Alum addition
Power:
1134327
1161350
333212
Mixers
Pumps:
ARCY
RAS
Blowers :
HP
427
1200
750
5400
kW
320
898
561
4039
IcWHr/
YEAR
2730566
7669094
4793184
34510925
Cost 8
$0.07/kWHr.
191140
536837
335523
2415765
Total power cost ($):
3479264
TOTAL 0 4 M COST ($):
6108153
-16-
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LOU LEVEL NUTRIENT DISCHARGE (TP - 0.5 mg/1: TH - 3 mg/1)
INCREMENTAL CONSTRUCTION COST
TANKAGE REQUIREMENT SUMMARY FOR LLND RETROFIT
Tankage
Required
lOOOcu.ft.
Anaeroblc(2Hr) 1014
1st Anoxic (3Hr) 1521
Aerobic(9Hr) 4562
2nd Anoxic(3Hr) 1521
Raarati.ond.Hr) 507
Total 9125
Raq'mts Addl'n
Mat by Tkg.
Exist Tkg Reqd.
lOOOcu. f tlOOOcu. ft .
0
0
1483
0
0
1483
TANKAGE REQUIREMENTS: (16" WALL, 14" BASE
No. of Tanks
Ho. of passes/tank
Length par pass (ft.)
Width par pass (ft.)
Dapth par pass (ft.)
Total voluma (cu.ft.)
No. of baff las /tank
MIXER REQUIREMENTS:
Volume of tanks (MG)
H.P. required (8 50 HP/MG)
No. of Mixers (10 HP/mixer).
No. of standby mixers
Total no. of mixers
No. of mixers existing,
No. of mixers existing
Anaerobic
Tankage
2
5
2*0
30
17
1224000
4
Anaerobic
Tankage
9.16
458
46
9
55
0
55
1014
1521
3079
1521
507
7642
SLAB AND
1st
Anoxic
Tankage
3
5
240
28
17
1713600
4
1 st
Anoxic
Tankage
12.82
641
64
13
77
0
77
Surf.
Area
Raqd.
sq.ft.
72000
100800
201600
100800
34560
509760
Land
Area
Available
sq.ft.
821900
8" BAFFLES)
Aerobic
Tankage
4
7
240
30
17
3427200
6
2 nd
Anoxic
Tankage
12.82
641
64
13
77
0
77
2nd
Anoxic Reaeration
Tankage Tankage
3
5
240
28
17
1713600
4
2
3
240
24
17
587520
2
AERATION REQUIREMENTS (Appendix C-8)
Plant design flowrate (MG)
Plant Influent BOD (mg/1)
Aeration Influent BOD (mg/1)
Plant Effluent BOD (mg/1)
BOD loading (mg/1)
Ammonia loading (mg/1)
Oxygen required (Ibs/MG)
Air required (SCFM)
Air required (SCFM)
(3 peaking factor of 2.2)
Existing capacity (SCFM)
91
135
88
12
76
18
1515
110100
242219
79300
Additional air required (SCFM)
162919
-17-
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CLARIFIERS REQUIREMENT:
To get over flow rate of 600 gpd/sq.ft;
Surface are*, required: 151667 sq.ft.
Existing surface area available: 84000 sq.ft.
Additional surface area required: 67667 sq.ft.
No. of clarlfler
Channels/tank
Diameter
Length
Width
Depth
4
5
n/a
200 ft.
17 ft.
14 ft.
PUMPING REQUIREMENT:
Existing capacity (MG) Additional capacity
Required
(mgd) (gpm) (mgd) (gpm)
ARCY PUMPS 8 400X 0 0 364 252776
RAS PUMPS 8 100Z Q 3 2083 88 61111
COST CALCULATIONS:
TANKAGE CONCRETE COST:
1st 2nd
Anaerobic Anoxlc Aerobic Anoxic Reaeration
Tankage Tankage Tankage Tankage Tankage
Concrete volumes:
sldewalls (cu.yd.) 403 403 403 403 403
endwalls (cu.yd.) 252 235 353 235 121
base slab (cu.yd.) 1624 1518 2256 1518 801
Concrete vol./tank (cu.yd.) 2279 2156 3012 2156 1325
Vol. of baffles (cu.yd.) 403 403 604 403 201
Concrete Cost per tank 901458 859330 1212810 859330 514113
(9 $342.50/cu.yd. for concrete;
$300.00/cu.yd. for baffles)
Total concrete cost ($) 1802915 2577990 4851240 2577990 1028225
Total concrete cost for
additional tankage ($). 12838360
MIXER COST:
1st 2 nd
Anaerobic Anoxic Anoxic
Tankage Tankage Tankage
Cost of mixers ($)
(9 $12,000 per mixer) 660000 924000 924000
Installation cost ($)
(3 20Z of mixer cost) 132000 184800 184800
Installed mixer cost ($) 792000 1108800 1108800
Total installed mixer cost ($) 3009600
-18-
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PUMP COST: (ARCY, RAS AND PUMP BUILDING)
No. of Unit Total
Pumps Cost (S) Cost (S)
ARCY PUMP:
24,500 gpm pump each 13 55000 715000
RAS PUMP:
14,350 gpm pump «ach 6 44000 264000
Subtotal 19 979000
Injtallatlon(20X) 195800
Subtotal 1174800
Pump buUdin«(40' x 110')
(« S40/sq. ft.) 176000
Total Cost ($) 1350800
CLARIFIER TANKAGE CONCRETE COST:
Concrete volumes:
sidevalls (cu.yd.) 3319
•ndwalls (cu.yd.) 470
base slab (cu. yd.) 3138
Concrete volume (cu.yd.) 6927
Concrete Coat
(C $342.50/cu.yd. for concretei 2372498
Equipment cost 8 40Z 948999
Installation 3 20Z 474500
Total cost for clariflers ($) 3795996
BLOWERS & DIFFUSERS COST
COST CONTROL TOTAL
QTY. SCFM EACH(S) PKG.(S) COST($)
Blovers 9 20000 120000 0 1080000
Installation 8 20Z 216000
DIFFUSERS
9 $30 per SCFM 162919 4887585
Total installed cost (S) 6183585
ANAEROBIC DIGESTION SUPERNATANT SYSTEM COST
Total coat ($) (Appendix C-15) 326163
ALUM FEED SYSTEM COST
Total cost ($) (Appendix C-17) 251766
TOTAL EQUIPMENT COST ($) :
27757122
-19-
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INCREMENTAL OHM COST SUMMARY:
Maintenance and materials cost
(3X of total construction)
$ 2106856
Labor cost:( current plant budget - $4,645,400)
25Z of existing budget is labor cost $ 1161350
Chemicals:
Includes Lime & Alum addition $ 885733
Power:
HP
1740
1950
900
8100
kU
1301
1459
673
kWHr/
YEAR
Cost 8
$0.07/kWBr.
Mixers
Pumps;
ARCY
RAS
Blowers:
Total Power Cose ($):
11118790 778315
12462278
5751821
6059 51766387
872359
" 402627
3623647
5676949
TOTAL 0 t M COST ($):
9830889
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TOTAL COST SUMMARY
INCREMENTAL CONSTRUCTIOH COST SUMMARY FOR RICHMOND WWTP, X $1000
COST ITEM HLND LLND
Tankage requirements $ 4359 12838
Mixers $ 749 3010
Clarifiers $ 3796 3796
Pumps-ARCY, RAS, Bldg. for pumps $ 920 1351
Alum Feed $ 218 252
Supernatant System $ 326 326
Blowers I Duffusers $ 4478 6184
Eff. Filter-Pumps, Structure, Media $
SUBTOTAL 14846 27757
Non Component Cost (1) 9502 17466
TOTAL CONSTRUCTION 24348 45223
Eng. & Const. Supervision(19X) (2) 4626 3592
SUBTOTAL 28974 53815
Contlngencles(20X) 5795 10763
Interest during construction(l/2PCI) 3042 5651
TOTAL CAPITAL COST 37311 70229
NOTES:
(1) Non-Component cost includes electrical, instrumentation,
yard piping, site preparation I misc. work, and
retrofit-construction added cost.
(2) Englneering(lOX), construction supervlsion(9X).
INCREMENTAL 0 & M COST SUMMARY
ITEM HLND LLND
Maintenance 4 Materials 1134 2107
Labor 1161 1161
Chemicals 333 886
Power 3479 5677
SUBTOTAL 6107 9831
TOTAL ANNUAL COST(l) 10209 17451
NOTES:
(1) Total annual cost is 0 & M cost and annualized capital using
0.1085 capital recovery factor at 8.875 X Interest rate.
-21-
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APPENDIX D-7
BACK RIVER
WASTEWATER TREATMENT PLANT
-------
TABIE OF CONTENTS
SECITCN PAGE
1.0 Description of Existing Facilities l
2.0 Proposed Plant Modifications 7
3.0 Proposed Retrofiting for Biological
Nutrient Removal 9
4.0 Total Cost Summary 18
-------
APPENDIX D-7
BACK RIVER WASTEWATER TREATMENT PLANT
1.0 DESCRIPTION OF EXISTING FACILITIES
The Back River WWTP is a secondary treatment facility, owned and operated
by the City of Baltimore with an average daily reported flow of 180 M3D.
Bethlehem Steel Corporation at its Sparrows Point Plant currently has an
agreement with the City to purchase and reuse about 100 MGD of the treated
water which is later discharged to Bear Creek. The remaining wastewater
from the City treatment plant is discharged to the Back River estuary.
Preliminary treatment facilities consist of inlet chambers, mechanical bar
screens, grit removal and flow meters. Secondary treatment is achieved by
primary sedimentation followed by fixed film trickling filters and humus
tanks (clarifiers) to control the sloughed solids from the trickling
filter media. Chlorine is added to the wastewater before its final
discharge to Back River. After secondary treatment, a portion of the
wastewater is diverted to additional sedimentation units before its
conveyance to the Bethelhem Steel Plant.
Primary sludge from the primary clarifier and dilution water from the
trickling filter is pumped to gravity sludge thickeners and was WAS is
pumped to flotation thickners. The thickened sludges are subjected to
high rate anaerobic digestion, elutriation, and centrifugal dewatering
before its final disposal as sludge cake.
Figure D.7.1 is a schematic of the existing plant showing the liquid
stream unit processes and the sludge treatment and handling facilities.
Figure D.7.2 shows the layout of the existing plant and D.7.3 and D.7.4
are the flow diagrams for the proposed scheme for HLND and LLND targets of
treatment.
All the unit treatment processes were designed based on an average design
flow of 80 MD discharged to Back River and 100 M3) discharged from
Bethelhem Steel to Bear Creek for a total average design for of 180 M3D.
The influent, effluent and current NPDES permit requirements for the Back
River plant is presented in Table D.7.1. It can be seen from Table D.7.1
that the treatment plant is not in compliance with existing effluent
limits. The plant has a current interim permit requirement of 3 mg/1 for
TKN (seasonal) and 2 mg/1 for total Phosphorous for the effluent used by
Bethlehem Steel. Effluent discharged to Back River must meet permit
requirements of 2.0 mg/1 Mi. (seasonal) and 0.2 mg/1 total Phosphorus.
-1-
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BACK
Parameter
BOD
SS
TP
NH.
4
TKN
N02
NO,
3
D.O.
Residual
CL2
N/A - not
N/R - not
RIVER RAW SEWAGE
(1984,
Influent, mg/1
221
178
6
N/A
N/A
N/A
N/A
N/A
N/A
available
required
1
TABLE D.7.1 •
INFLUENT, EFFLUENT AND CURRENT (1987) NPDES
PERMIT REQUIREMENTS •
1985, 1986 ANNUAL AVERAGE) |
Effluent, mq/1 NPDES Permit I
Back. River Bethelhem Steel
22 10 20 •
28 10 30
1 0.2 2.0 §
16 2.0 (4/15) N/R _
to |
(10/15) •
24 3 (4/15) ' N/R •
to |
(10/15)
1.68 N/R N/R 1
0.23 N/R N/R
N/A 5 5 1
N/A 0.5 0.02 |
1
1
1
1
1
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The existing plant component and sizes are presented below:
Secondary Treatment
Primary Settling Tanks
Trickling Filters
Activated Sludge Tanks
Final Settling Tanks
Humus Tanks
Sludge Treatment
Gravity Sludge Thickeners
Flotation Thickner
Anaerobic Digesters
Sludge Storage Tanks
Elutriation Tanks
2 @ 200 ft dia. x 12 ft SWD; 9 § 170 ft dia.
x 12.5 ft SWD. Total volume = 24.74 M3; area
= 267,114 sqft.
Volume = 256 acre ft (ll,1513x io3 cu ft);
area - 30 acres (1306.7 x 10 sqft).
Volume = 10.72 M3; area
15.6 ft.
91,920 sqft; SWD =
Volume =7.04 MS; area = 75,820 sqft; 2 i 126
ft dia. 13.3 SWD; 3 @ 180 ft dia. x 12 ft
SWD.
Volume = 3 MG; area - 104,494 sqft; 4 @ 143
ft x 143 ft x 10 ft SWD; 1 @ 170 ft dia. x 9
ft SWD;
Area = 26,400 sqft, diameter = 65 ft, SWD =
9.5 ft, volume » 2.172 MS.
Area = 3930 sqft dia. » 50 ft SWD = 12.25 ft.
Area = 47,100 soft, diameter = 100 ft, SWD =
26.5 ft, volume = 8.08 MS.
Area = 10,000 sq ft, diameter = 80 ft, SWD =
15 ft, volume = 1.122 MS.
4 @ 525 sq ft each; 2 § 750 sq ft, total area
= 3600 sq ft.
Vaccum Filters/Centrifuges 2 @ 140 gpm each (260 gpm max) 6% TS feed.
2.0 PROPOSED PLANT MODIFICATIONS:
The Back River estuary is a severly stressed ecosystem suffering from
heavy nutrient loads that encourage algae growth and result in the
depletion of the oxygen necessary to sustain healthy aquatic life.
Identified as the major source of nutrients and oxygen demand, the Back
River plant discharge is subjected to stringent effluent limitations. The
City of Baltimore thus started selecting the most cost effective and
environmentally sound means of treating the existing and anticipated
-7-
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wastewater flows to be in compliance with the discharge permit. A two
phase facility plan for recommended improvements for a period of 20 years
starting in 1983 has been prepared. The effluent limits defined for
continued discharge to Back River requires Advanced Wastewater Treatment
(AWT) which employs processes for removing nutrients (Phosphorus and
nitrogen) as well as increased levels of the more conventional pollutants
including BOD and SS. The effluent permit requirement to Bethelhem Steel
also require Advanced Wastewater Treatment (AWT) levels which limits the
BOD, SS, Phosphorous, and nitrogen concentration.
Following is the list of liquid treatment processes to be modified as a
part of the present upgrading plan:
- A new fine bubble air activated sludge plant (126 M3D) will be
constructed to replace the trickling filters to provide an effluent
quality meeting 20/30 mg/1 BOD and suspended solids limits. After
the new activated plant becomes operational, the trickling filters
can be removed from service.
- Phosphorous reduction will be achieved by adding waste pickle
liquor to produce an effluent with less than 2 mg/1 of phosphorous.
In the future provisions will be made to add ferric chloride to
the final settling tanks to reduce the total Phosphorous levels to
less than 1 mg/1.
- Tertiary filtration of the effluent from the activated sludge
process will be provided to further reduce Phosphorous levels to
0.2 mg/1, TKN to 3 mg/1 and BOD5 and suspended solids to 10 mg/1.
- The plant effluent will be disinfected using chlorination and
dechlorination.
Following is the list of sludge management processes to be upgraded:
- Dissolved air flotation units will be constructed to thicken the
biological sludges and thereby improve the operation of the
existing digesters. The existing gravity thickeners, digesters,
and centrifuges will continue to be used.
- A full service composting operations service for design,
construction, maintenance and marketing will be established.
Initially all sludge produced will continue to be hauled under
contract to approved land application sites.
The treatment plant is now under expansion to construct a new fine bubble
126 M3) activated sludge plant. Plant officials are currently
investigating the alternative issue of selecting a cost effective process
with a design safety factor of 1.5 that may be imposed by the EPA instead
of the factor of 2.25 that was used in originally selecting a single-stage
biological nitrification system using a powdered activated carbon process.
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The planned expansion now does not include the powdered
carbon process and officials are currently evaluating
alternatives to replace it. A task force committee has
been established to evaluate different processes and
select the best alternative.
3.0 PROPOSED RETROFITTING FOR BIOLOGICAL NUTRIENT
REMOVAL
The proposed retrofit for BNR process would include the
three (3) stage A20 process for HLND and five (5)
stage Bardenpho Process for LLND. The existing
treatment scheme has trickling filters as secondary
treatment. The area utilized by the trickling filters
would be utilized to meet the tankage volume
requirements for HLND and LLND targets. The plant
currently does not have any teriary filters and thus
secondary clarifiers would be added to obtain an
overflow rate of 400 gpd/sg ft. A new aeration system
will be needed to meet the oxygen requirements.
The retrofit details of the two levels of treatment are
presented as follows:
-9-
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HIGH LEVEL NUTRIENT DISCHARGE (TP = 2 mg/1; TN = 8 uig/L)
INCREMENTAL CONSTRUCTION COST
TANKAGE REQUIREMENT SUMMARY FOR HLND RETROFIT
Tankage Req'mts Addl'n Surf. Land
Required Met by Tkg. Area Area
'Exist. Tk Reqd. Reqd. Available
1000 cu.ft. 1000 eu.ft. sq. ft. sq. ft.
Anaerobic(IBr.) 1164 0 1164 73320
AnoxicdHr.) 1164 0 1164 73320
Aerobic(6Hr.) 6985 1433 5552 357120
Total 9313 1433 7880 503760 1306700
TANKAGE REQUIREMENTS:(16" WALL, 14" BASE SLAB AND 8" BAFFLES)
Anaerobic Anoxic Aerobic
Tankage Tankage Tankage
No. of Tanks 338
No. of passes/tank 4 4 6 .
Length per pass (ft) 235 235 240
Width per pass (ft) 26 26 31
Depth per pass (ft) 16 16 16
Total volume (cu.ft.) 1173120 1173120 5713920
No. of baffles/tank 335
MIXER REQUIREMENTS:
Anaerobic Anoxic
Tankage Tankage
Volume of tanks (MG) 8.71 8.71
H.P. required (8 50 HP/MG) 436 436
No. of Mixers (10 HP/mixer) 44 44
No. of standby mixers 9 9
Total no. of mixers 52 52
No. of mixers existing 0 0
No. of mixers required 52 52
AERATION REQUIREMENTS (Appendix C-8)
Plant design flowrate (MG) 209.00
Plant Influent BOD (mg/1) 221.00
Aeration Influent BOD (mg/1) 190.00
Plant Effluent BOD (mg/1) 22.00
BOD loading (mg/1) 168
Ammonia loading (mg/1) 16
Oxygen required (Ibs/MG) 2155
Air required (SCFM) 302205
Air required (SCFM) 604410
(@ peaking factor of 2.0)
Existing capacity (SCFM) 96500
Additional air required (SCFM) 507910
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CLARIFIERS REQUIREMENT:
To get over flow race of 400 gpd/sq.ft;
Surface area required:
Existing surface area available:
Additional surface area required:
522500 sq.ft.
101279 sq.ft.
421221 sq.ft.
No. of clarifler
Channels/tank
Diameter
Length
Width
Depth
17
n/a
180 ft.
n/a
n/a
12 ft.
PUMPING REQUIREMENT:
Existing Capacity Additional Capacity
Required
(mgd) (gpm) (mgd) (gpm)
ARCY PUMPS g 200ZQ 0 0 418 290276
RAS PUMPS 8 75XQ 47 32639 110 76215
COST CALCULATIONS:
TANKAGE CONCRETE COST:
Anaerobic Anoxlc Aerobic
Tankage Tankage Tankage
Concrete volumes:
sidewalls (cu.yd.) 371 371 379
endwalla (cu.yd.) 164 164 294
base slab (cu.yd.) 1115 1115 2003
Concrete vol./tank (cu.yd.) 1650 1650 2676
Vol. of baffles (cu.yd.) 279 279 474
Concrete Cost per tank 648939 648939 1058802
(8 $342.50/cu.yd. for concrete;
$300.00/cu.yd. for baffles)
Total concrete cost ($) 1946818 1946818 8470415
Total concrete cost for
additional tankage ($). 12364050
MIXER COST:
Anaerobic Anoxic
Tankage Tankage
Cost of mixers ($) 624000 624000
(3 $12,000 per mixer)
Installation cost ($) 124800 124800
(8 20X of mixer cost)
Installed mixer cost ($) 748800 748800
Total installed mixer cost ($) 1497600 ,
-11-
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PUMP COST: (ARCY, HAS AND PUMP BUILDING) No. of Unit Total
Pumps Cost(S) Cost(S)
ARCY PUMP:
72,500 gpo pumps each 6 100000 600000
RAS PUMP:
24,500 gpm pump each 5 55000 275000
Subtotal 11 875000
Installation(20I) 175000
Subtotal 1050000
Pump buUdlng<60' x 60')
9 ($40/sq.ft.) 144000
Total cost ($) 1194000
CLARIFIER TANKAGE CONCRETE COST:
Concrete volumes:
sidewalls (cu.yd.) 8640
endwalls (cu.yd.) 0
base slab (cu. yd.) 19532
Concrete volume (cu.yd.) 28172
Concrete Cost
(8 $342.50/cu.yd. for concrete) 9648910
Equipment cost 9 40Z 3859564
Installation 9 20X 1929782
Total cost for clariflers ($) 15438256
BLOWERS & DIFFUSERS COST
COST CONTROL TOTAL
QTY. SCFM EACH(S) PKG.<$) COST($)
Blovers 26.00 20000 120000 2000 3172000
Installation 13 20X 634400
Diffusers
9 $30 per SCFM 507910 15600000
Total installed cost ($) 19406400
ANAEROBIC DIGESTION SUPERNATANT SYSTEM COST:
Total cost ($) (Appendix C-15) 583726
ALUM FEED SYSTEM COST:
Total cost ($) (Appendix C-17) 501600
TOTAL EQUIPMENT COST (S):
50986000
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INCREMENTAL 0 4 M COST SUMMARY:
Maintenance and materials cost:
(3Z of total construction)
Labor cost:( current plant budget « $7,000,000)
25X of existing budget is labor cost
Chemicals :
Includes Lion 1 Alum addition
Power:
3901610
1750000
765288
Mixers
Pumps:
ARCY
RAS
Blowers :
HP
871
2400
750
23400
kW
652
1795
561
17503
kWHr/
YEAR
5566484
15338189
4793184
149547341
Cost 3
S0.07/kUBr.
389654
1073673
335523
10468314
Total power cost:
TOTAL 0 & M COST <$) :
12267164
18684062
-13-
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LOW LEVEL NUTRIENT DISCHARGE (TP - 0.5 mg/1; TN = 3 mg/1)
INCREMENTAL CONSTRUCTION COST
TANKAGE REQUIREMENT SUMMARY FOR LLND RETROFIT
Tankage
Required
lOOOcu.ft.
Anaerobic(2Hr) 2328
1st Anoxic(3Hr) 3493
Aerobic(9Hr) 10478
2nd Anoxic (3Hr) 3493
Rearatlon(lHr) 1164
Total 20956
Req'mts Addl'n
Met by Tkg.
Exist Tkg Reqd.
lOOOcu.ft lOOOcu.ft.
0
0
1433
0
0
1433
TANKAGE REQUIREMENTS: (16" WALL, 14" BASE
No. of Tanks
No. of passes /tank
Length per pass (ft.)
Width per pass (ft.)
Depth per pass (ft.)
Total volume (cu.ft.)
No. of baffles/tank
MIXER REQUIREMENTS:
Volume of tanks (MG)
H.P. required (3 50 HP/MG)
No. of Mixers (10 HP/mixer)
No. of standby mixers
Total no. of mixers
No. of mixers existing
No. of mixers required
Anaerobic
Tankage
6
4
230
24
20
2649600
3
Anaerobic
Tankage
19.82
991
99
20
119
0
119
2328
3493
9045
3493
1164
19523
SLAB AND
1st
Anoxic
Tankage
7
4
250
25
20
3500000
3
1 st
Anoxic
Tankage
26.18
1309
131
26
157
0
157
Surf .
Area
Reqd.
sq.ft.
132480
175000
459000
175000
60000
1001480
Land
Area
Available
sq.ft.
1306700
8" BAFFLES)
Aerobic
Tankage
10
6
255
30
20
9180000
5
2 nd
Anoxic
Tankage
26.18
1309
131
26
157
0
157
2nd
Anoxic
Tankage
7
4
250
25
20
3500000
3
Reaeration
Tankage
2
4
250
30
20
1200000
3
AERATION REQUIREMENTS (Appendix C-8)
Plant design flowrate (MG)
Plant Influent BOD (mg/1)
Aeration Influent BOD (mg/1)
Plant Effluent BOD (mg/1)
BOD loading (mg/1)
Ammonia loading (mg/1)
Oxygen required (Ibs/MG)
Air required (SCFM)
Air required (SCFM)
(@ peaking factor of 2.0)
Existing capacity (SCFM)
Additional air required (SCFM)
209
221
190
22
168
16
2435
377501
755003
96500
658503
-14-
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CLARIFIERS REQUIREMENT:
To get over flow rate of 400 gpd/sq.ft;
Surface area required: 522500 sq.ft.
Existing surface area available: 101279 sq.ft.
Additional surface area required: 421221 sq.ft.
No. of clarifier
Channels/tank
Diameter
Length
Width
Depth
17
n/a
180 ft.
n/a
n/a
12 'ft.
PUMPING REQUIREMENT:
Existing capacity (MG) Additional capacity
Required
(mgd) (gpm) (mgd) (gpm)
ARCY PUMPS 8 400X 0 0 836 580552
RAS PUMPS a 100X Q 63 43750 146 101388
COST CALCULATIONS:
TANKAGE CONCRETE COST:
1st 2nd
Anaerobic Anoxic Aerobic Anoxic Reaeration
Tankage Tankage Tankage Tankage Tankage
Concrete volumes:
sldewalls (cu.yd.) 454 494 504 494 494
endvalls (cu.yd.) 190 198 356 198 237
base slab (cu.yd.) 1011 1141 2059 1141 1361
Concrete vol./tank (cu.yd.) 1655 1833 2919 1833 2092
Vol. of baffles (cu.yd.) 341 370 630 370 370
Concrete Cost per tank 669138 738803 1188758 738803 827510
(9 $342.50/cu.yd. for concrete;
$300.00/cu.yd. for baffles)
Total concrete cost ($) 4014825 5171618 11887575 5171618 1655020
Total concrete cost for
additional tankage ($). ' 27900655
MIXER COST:
1st 2 nd
Anaerobic Anoxic Anoxic
Tankage Tankage Tankage
~> .
Cost of mixers ($)
(8 $12,000 per mixer) 1428000 1884000 1884000
Installation cost ($)
(3 20X of mixer cost) 285600 376800 376800
Installed mixer cost ($) 1713600 2260800 2260800
Total installed mixer cost ($) 6235200
-15-
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PUMP COST: (ARCY, RAS AND PUMP BUILDING)
No. of Unit Total
Pumps Cost(S) Co3t(S)
ARCY PUMP:
72,500 gpm pump each 10 100000 1000000
RAS PUMP:
24,500 gpm pump each 6 55000 330000
Subtotal 16 1330000
Installation(20X> 266000
Subtotal 1596000
Pump buUdinc(60> x 60'}
(8 $40/sq. ft.) 144000
Total cost ($) 1740000
CLARIFIER TANKAGE CONCRETE COST:
Concrete volumes:
sldewalls (cu.yd.) 8640
endwalls (cu.yd.) 0
base slab (cu. yd.) 19532
Concrete volume (cu.yd.) 28172
Concrete Cost
(8 $342.50/cu.yd. for concrete! 9648910
Equipment cost 8 40Z 3859564
Installation 8 20X 1929782
Total cost for clarifiers ($) 15438256
BLOWERS S, DIFFUSERS COST
COST CONTROL TOTAL
QTY. SCFM EACH(S) PKG.($) COST(S)
Blowers 33 20000 120000 0 3960000
Installation 8 20X 792000
DIFFUSERS
8 $30 per SCFM 658503 19755077
Total Installed cost 24507077
ANAEROBIC DIGESTION SUPERNATANT SYSTEM COST
Total cost ($) (Appendix C-15) 583726
ALUM FEED SYSTEM COST
Total cost ($) (Appendix C-17) 578233
TOTAL EQUIPMENT COST ($) :
76983144
-16-
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1
INCREMENTAL 0 & M COST SUMMARY:
Maintenance and materials cost
(32 of total construction) S 5866142
Labor cost:( current plant budget - $7,000,000)
25 X of existing budget is labor cost $ 1750000
Chemicals :
Includes Lime 6 Alum addition $ 2038098
Power:
kWHr/ Cost 8
HP kW YEAR $0.07/kWHr
Mixers 3609 2699 23064484 1614514
Pumps:
ARCY 4000 2992 25563648 1789455
RAS 900 673 5751821 402627
Blowers: 29700 22216 189810086 13286706
Total Power Cost ($): 17093303
TOTAL 0 S M COST (S) : 26747543
-17-
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TOTAL COST SUMMARY
INCREMEHTAL CONSTRUCTION COST SUMMARY FOR BACKRIVER WWTP, X $1000
COST ITEM HLND LLND
Tankage requirements $ 12364 27901
Mixers $ 1498 6235
Clarifiers $ 15438 15438
Pumps-ARCY, RAS, Bldg. for pumps $ 1194 1740
Alum Feed $ 502 578
Supernatant System $ 584 584
Blowers & Duffusers $ 19406 24507
Eff. Filter-Pumps, Structure, Media $
SUBTOTAL 50986 76983
Non Component Cost (1) 32760 48931
TOTAL CONSTRUCTION 83746 125914
Eng. & Const. Supervision(19X) (2) 15912 23924
SUBTOTAL 99658 149838
Contingencies(20X) 19932 29968
Interest during construction(l/2PCI) 10464 15733
TOTAL CAPITAL COST 130054 195538
NOTES:
(1) Non-Component cost Includes electrical, instrumentation,
yard piping, site preparation I misc. work, and
retrofit-construction added cost.
(2) Engineering(102), construction supervision(9X).
INCREMENTAL 0 & M COST SUMMARY
ITEM HLND LLND
Maintenance & Materials 3902 5866
Labor 1750 1750
Chemicals 765 2038
Power 12267 17093
SUBTOTAL 18684 26747
TOTAL ANNUAL COST(l) - 32795 47963
NOTES:
(1) Total annual cost is 0 & M cost and annualized capital using
0.1085 capital recovery factor at 8.875 Z interest rate.
-18-
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APPENDIX D-8
BLUE PLAINS WASTEWATER TREATMENT PLANT
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TABLE OF CONTENTS
SECTION PAGE
1.0 Description of Existing Facilities 1
2.0 Proposed Plant Modifications 8
3.0 Proposed Retrofiting for Biological
Nutrient Removal 10
4.0 Total Cost Summary 16
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APPENDIX D-8
BLUE PLAINS WASTEWATER TREATMENT PLANT
1.0 DESCRIPTION OF EXISTING FACILITIES
Construction of Advanced Waste Treatment (AWT)
facilities at the Blue Plains WWTP began in 1972 and
the new facilities were placed into operation in 1983.
The plant was designed for an average daily flow of 309
mgd. The existing treatment facility consists of
primary treatment followed by secondary treatment and
nitrification using air-activated sludge. Coarse
bubble diffusers are used for aeration in secondary
treatment and deep multi-stage reactors equipped with
sparged-air turbines are used for nitrification. The
nitrified effluent is filtered through dual-media
filters and disinfected prior to its discharge to the
Potomac River. Chemicals are added at multiple
locations in the treatment system. These include
ferric chloride for phosphorus removal in the primary
sedimentation tanks, waste pickle liquor and ferric
chloride in the secondary sedimentation tanks and lime
for pH adjustment in the nitrification reactors. Storm
water flows to the Blue Plains WWTP exceeding 650 MGD
receive partial treatment consisting of screening, grit
removal, primary sedimentation and chlorination before
its discharge to the river.
Primary ^sludge in the existing facility is gravity
thickened; waste secondary sludge and waste nitrified
sludge are thickened by dissolved-air flotation.
Thickened primary sludge is anaerobically digested and
the digested sludge is elutriated in the flotation
thickeners, then polymer-conditioned and
centrifugally-dewatered. The dewatered digested sludge
is limed and hauled to an offsite location. Thickened
excess primary sludge, waste secondary sludge and waste
nitrified sludge are conditioned with lime and ferric
chloride and dewatered on vacuum filters.
Figure D.8.1 is a schematic showing the existing and
expanded liquid stream unit processes. Figure D.8.2 is
the layout for the wastewater treatment plant. Figure
D.8.3 and D.8.4 are the process flow schemes proposed
to meet the levels of High Level Nutrient Discharge
(HLND) and Low Level Nutrient Discharge (LLND).
-1-
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O MOJICTI THAT UK nJUT-
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WASTEWATER TREATMENT PLANT
DISTRICT OF COLUMBIA
WATER AND SEWER UTILITY ADMINISTRATE)
DEPARTMENT OF PUBLIC WORKS
SITE PLAN
KALI r-IOO'
Figure D.8.2
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The present design flow and wastewater characteristics
are described below:
The treatment plant is designed for an average dry
weather flow of 309 MGD with a maximum flow capacity of
650 MGD. Primary clarification capacity is provided to
treat an additional 289 MGD of storm generated combined
sewer flows. Table D.8.1 summarizes the influent and
effluent wastewater parameters and the current NPDES
permit requirements. The plant has a 1 mg/1 ammonia
nitrogen limit in summer months and 6.5 mg/1 ammonia
nitrogen from December to April. The current plant
performance is excellent in meeting effluent
limitations including BOD, solids, and nutrients.
The existing plant component and unit sizes are
presented below:
Screening:
Pumping:
Grit Removal:
Mechanical bar screens, 1" clear
opening capable of handling 900 mgd
6 pumps, total capacity of 400 mgd.
9 pumps, total capacity of 100 mgd,
3 of which are run by internal
combustion engines.
16 units each at detention time of
3.4 minutes at maximum flow of 673
mgd.
Primary Treatment: 20 clarifiers on east side, each 106
feet dia. X 13.7 feet deep; surface
area 226,200 sqft, capacity 24.16
MG.
16 clarifiers on west sside, each 106
feet dia. X 13.7 feet deep, surface
* area 141,200 sqft, capacity 14.44 MG,
Secondary
Treatment:
2 tanks, 4 passes/tank,, each 460 ft
(length) X 29 ft (width) X 15 ft
(depth). 2 tanks, 4 passes/tank,
each 119 ft (length) X 20 ft (width)
X 15 ft (depth). Total detention
time 2 hrs (at a flow of 309 mgd).
-6- .
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Chemical Addition;
Secondary
Sedimentation:
Alum feed rate of up to 83,900
gals/day or ferric chloride feed
rate up to 49,500 gpd.
12 tanks on east side each 248,000
sqft surface area.
12 tanks on west side each 237,000
sqft. Average detention time of 2.7
hours.
Nitrification
Reactors:
Nitrification
Sedimentation
Tanks:
Air Blowers:
Auxiliary
Sedimentation
Tanks:
Filter
Influent Pumps:
Mixed Media
Filters:
Disinfection
Capacity:
Sludge Thickners
12 tanks; each 80 feet W X 249 feet
L X 30.9 feet D, 59 stages in each
tank with average detention time of
4 hours; 55.18 MG capacity.
28 tanks, each 79 feet W, 242 feet L
X 15.5 feet D; average detention
time of 4.5 hours; 535,300 sqft
surface area.
5 blowers
8 each, 153,000 sqft
10 each
36 gravity flow units; 74,800 sqft 4
additional, 8,320 sqft. Total
surface area 80,200 sqft.
740 MGD: chlorine contact tanks have
detention period of 48 minutes at
average flow.
8 tanks, each 65 feet dia. X 10
feet D; 26,546 sqft total.
-7-
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Flotation
Thiclcners: 18 units, each 20 feet W X 59 feet L
X 14 feet D; 19,800 sqft total.
Sludge Digestion: 12 fixed cover tanks; total volume
1,710,000 cuft. Sludge gas is used
to heat 63,000,000 BTU/hr heat
exchangers to maintain contents at
95°F.
Elutriation Tanks: 4 tanks; total volume of 100,000
cuft.
Vacuum Filtration: 30 filters, up to 2400 tons/day
sludge containing 15% to 20% solids.
2.0 PROPOSED PLANT MODIFICATIONS
Feasibility studies were carried out in accordance with
the Administrative Order issued by the U.S.
Environmental Protection Agency (EPA) to the District
of Columbia examining wastewater treatment, needs
through the year 2005. The study examined expanding
the existing treatment facility to meet future needs,
diverting future wastewater flows for treatment to
other locations both within and outside the Blue Plains
area, water quality modeling and examination of the
impact of adjacent wastewater treatment plants.
The studies indicated that the existing treatment works
at Blue Plains, with improvements, have the capacity to
treat annual average wastewater flows of 310 MGD to
meet the existing NPDES permit which expires on October
29, 1991.
Estimates of future needs indicate that the Blue Plains
service area will' require treatment capacity for annual
average wastewater quantities of about 370 MGD. Flow
diagrams for the expanded liquid process and solids
process facilites is shown on Figures D.8,,1.
Major improvements in the liquid process includes the
conversion of secondary aeration tanks to step aeration
and that the denitrification area be converted to
additional sedimentaion basins and sludge composting.
-8-
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TABLE D.8.1
BLUE PLAINS WWTP RAW SEWAGE AND EFFLUENT CHARACTERISTICS
(SEPTEMBER 1984 to July 1987)
Parameter
TSS, mg/1
BOD-, mg/1
TP, mg/1
TKN, mg/1
NH3-N, mg/1
NO-j-N, mg/1
N02~N, mg/1
D.O., mg/1
PH
Total C12, mg/1
Zinc, ppb
Mercury, ppb
Copper, ppb
Chromium (Hex.), ppb
Cadmium, ppb
Iron, mg/1
Lead , ppb
Influent Effluent
142 1.5
132 1.5
4.2 0.12
23.8 0.735
12.1 0.5
11.7
0.010
— —
— —
—
14.0
0.100
5.80
14.40
0.422
0.150
4.88
NPDES Permit
7.0
5.0
0.18
N/A
1.0 (5/1 - 11/30)
6.5 (12/1 - 4/30)
N/A
N/A
4.0 (not less than)
6 - 8.5
0.02
N/A
N/A
N/A
N/A
N/A
N/A
N/A
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3.0 PROPOSED RETROFITTING FOR BIOLOGICAL
NUTRIENT REMOVAL
The current NPDES permit requires 0.18 mg/1 of phosphorus
year round and 1.0 mg/1 and 6.5 mg/1 of ammonia nitrogen
in summer and winter respectively. The treatment plant
performance is excellent so far and has facilities for
nitrification for ammonia removal and chemical addition
for phosphorous removal. Nutrient levels are currently
well under the discharge requirements. Selecting a low
level biological nutrient removal system would require
much more tankage than the high level design and for 309
MGDf would be very costly.
For the HLND requirements , the design calls for the
addition of areation basins where as the volume
requirements for the anaerobic and anoxic Zones could
be accommodated internally. Addition of secondary
clarifiers would be necessary to obtain an overall
overflow rate of 600 gpd/sq ft. Additional blower
would be necessary to meet oxygen demand at a higher
peaking factor. For the low level discharge
requirements, the plant visits indicated that land
availabilty to accomodate the five (5) stage Bardenpho
Process is not feasible. Alternatively, the LLND
discharge requirements could be achieved by a three (3)
stage A20 Process with alum addition and converting
the existing filters to deep bed denitrification
filters with methanol addition- facilities.
The cost estimates for HLND and LLND requirements are
presented as follows:
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HIGH LEVEL NUTRIENT DISCHARGE (TP = 2 mg/1; IN - 8 mg/1)
INCREMENTAL CONSTRUCTION COST
TANKAGE REQUIREMENT SUMMARY FOR HLND RETROFIT
Tankage Req'mts Addi'n Surf. Land
Required Met by Tkg. Area Area
Exist. Tk Reqd. Reqd. Available
1000 cu.ft.1000 eu.ft. sq. ft. sq. ft.
Anaerobic(IHr.) 2629 2629
Anoxic(IHr.) 2629 2629
Aerobic(6Hr.) 15775 11573 4202 140400
Total 21033 16831 4202 140400 350400
TANKAGE REQUIREMENTS: (16" WALL, 14" BASE SLAB AND 8* BAFFLES)
Anaerobic Anoxic Aerobic
Tankage Tankage Tankage
No. of Tanks 006
No. of passes/tank 003
Length par pass (ft) 0 0 260
Width per pass (ft) 0 0 30
Depth per pass (ft) 0 '0 31
Total volume (eu.ft.) 0 0 4352400
No. of baffles/tank 0 0.2
MIXER REQUIREMENTS:
Anaerobic Anoxic
Tankage Tankage
Volume of tanks (MG) 19.66 19.66
H.P. required (8 50 HP/MG) 983 983
No. of Mixers (10 HP/mixer) 98 98
No. of standby mixers 20 20
Total no. of mixers 118 118
No. of mixers existing 0 0
No. of mixers required 118 118
AERATION REQUIREMENTS (Appendix C-8)
Plant design flowrate (MG) 472.00
Plant Influent BOD (mg/1) 102.00
Aeration Influent BOD (mg/1) 70.00
Plant Effluent BOD (mg/1) 1.10
BOD loading (mg/1) 69
Ammonia loading (mg/1) 12
Oxygen required (Ibs/MG) 1092
Air required (SCFM) 345974
Air required (SCFM) 726545
(9 peaking factor of 2.1)
Existing capacity (SCFM) 539056
Additional air required (SCFM) 187489
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CLARIFIERS REQUIREMENT:
To get over flow rate of 600 gpd/sq.ft;
Surface area required: 786667 sq.ft.
Existing surface area available: 535304 sq.ft.
Additional surface area required: 251363 sq.ft.
Ho. of clarifiers 12
Channels/tank 3
Diameter n/a
Length 300 ft.
Width 25 ft.
Depth 18 ft.
PUMPING REQUIREMENT:
Existing Capacity Additional Capacity
Required
(mgd) (gpn) (mgd) (gpo)
ARC? PUMPS 8 200JCQ 0 0 944 655551
RAS PUMPS 3 75XQ 142 98610 212 147221
COST CALCULATIONS:
TANKAGE CONCRETE COST:
Anaerobic Anoxlc Aerobic
Tankage Tankage Tankage
Concrete volumes:
sidewalls (cu.yd.) 0 0 796
endwalls (cu.yd.) ,0 0 276
base slab (cu.yd.) 0 0 1072
Concrete vol./tank (cu.yd.) 0 0 2144
Vol. of baffles (cu.yd.) 0 0 398
Concrete Cost per tank 0 0 853720
(8 $342.50/cu.yd. for concrete:
$300.00/cu.yd. for baffles)
Total concrete cost ($) 0 0 5122320
Total concrete cost for
additional tankage ($). 5122320
MIXER COST:
Anaerobic Anoxic
Tankage Tankage
Cost of mixers ($) 1416000 1416000
(8 $12,000 per mixer)
Installation cost ($) 283200 283200
(8 20X of mixer cost)
Installed mixer cost ($) 1699200 1699200
Total installed mixer cost ($) 3398400
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PUMP COST: (ARCY, HAS AMD PUMP BUILDING) Ho. of Unit Total
Pumps Cost($) Cost(S)
ARCY PUMP:
72,000 gpo pumps each 13 100000 1300000
RAS PUMP: '
2A.500 gpm pump each 9 55000 495000
Subtotal 22 1795000
Installation^*) 359000
Subtotal 2154000
Pump building(60* x 100')
3 ($40/sq.ft.) 240000
Total coat ($) 2394000
CLARIFIER TANKAGE CONCRETE COST:
Concrete volumes:
sidevalls (cu.yd.) 12800
endvalls (cu.yd.) 1600
base slab (cu. yd.) 12453
Concrete volume (cu.yd.) 26853
Concrete Cost
(8 $3*2.50/cu.yd. for concrete) 9197153
Equipment cost « 40X 3678861
Installation 9 20X 1839431
Total cost for elariflers ($) 14715444
BLOWERS (. DIFFUSERS COST
COST CONTROL TOTAL
QTY. SCFM EACH(S) PKG.(S) COST($)
Blowers 10.00 20000 120000 0 1200000
Installation 8 20Z 240000
Diffusers
3 $30 per SCFM 6000000
Total installed cost ($) 7440000
ANAEROBIC DIGESTION SUPERNATANT SYSTEM COST:
Total cost ($) (Appendix C-15) 1032440
ALUM FXED SYSTEM COST:
Total cost ($) (Appendix C-17) 1132800
TOTAL EQUIPMENT COST ($):
35234000
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INCREMENTAL O t M COST SUMMARY:
Maintenance and materials coat:
(3Z of total construction) 2682300
Labor cost:( currant plant budget - $16,872,000)
25X of existing budget is labor cost 4218000
Chemicals:
Includes Lime & Alum addition 1728310
Power:
kWHr/ Cost £
HP kW YEAR $0.07/kWHr.
Mixers 1966 1471 12882176 901752
Pumps:
ARCY 5200 3890 34072896 2385103
RAS 1350 1010 8845848 619209
Blowers: 9000 6732 58972320 4128062
Total power cost ($): 8034127
TOTAL 0 t M COST ($) : 16662737
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LOW LEVEL HUTMENT DISCHARGE (TP - 0.5 mg/ls TN - 3 mg/1)
INCREMENTAL CONSTRUCTION COST
TANKAGE REQUIREMENT SUMMARY FOR LLHD RETROFIT
Tankage Req'mts Addl'n Surf. Land
Required M«t by Tkg. Ar«« Ar«a
Exist Tkg. Reqd. Reqd. Available
lOOOcu.ft.'lOOOcu.ft. lOOOcu.ft. sq.ft. sq.ft.
Anaerob to ( 2Hr )
1st Anoxlc(3Hr)
A«robic(9Hr)
2nd Anoxic(3Hr)
Rearation(lHr)
Total
5258
7887
23661
7887
2629
47322
0
0
16831
0
0
16831
5258
7887
6830
7887
2629
30491 983580 * 377856
* Based on an average depth of 31 ft.
From th« above table It Is determined that due to the shortage of land
availability It will not be feasible to retrofit the 5 stage Bardenpho
process to meet the LLND limits.
Alternatively the LLND limits caa be achieved by retrofiting the
3 stage A20 process with alum addition and converting the existing
filters to deep bed denitrlficatlon filters with methanol addition
facilities.
Total equipment cost for HLNO ($) 35234000
Equipment cost for denltrification filters ($) 23574000
TOTAL EQUIPMENT COST ($): 58808000
* NOTE: The cost provided for the denitrification filters is not
site specific but based on a generic retrofit.
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TOTAL COST SUMMARY
INCREMENTAL CONSTRUCTION COST SUMMARY FOR BLUE PLAINS WUTP, X $1000
COST ITEM HLND LLND
Tankage requirements $ 5122 S122
Mixers $ 3398 3398
Clarifiers $ 14715 14715
Pumps-ARCY, RAS, Bldg. for pumps $ 2394 2394
Alum P««d $ 1133 1133
Supernatant System $ 1032 1032
Blowers & Duffusers $ 7440 7440
Sf£. Filter-Pumps, Structure, Media $ 23574
SUBTOTAL 35234 58808
Non Component Cost (1) 22340 57701
TOTAL CONSTRUCTION 57574 116509
Eng. & Const. Supervlsion(19X) (2) 10939 22137
SUBTOTAL 68513 138646
Contlngencles(20Z) 13703 27729
Interest during cons truerion(l/2PCI) 7194 14558
TOTAL CAPITAL COST 89410 180933 (3)
NOTES:
(1) Non-Component cost includes electrical, instrumentation,
yard piping, site preparation & misc. work, and
retrofit-construction added cost.
(2) Engineering(10X), construction supervislon(9Z).
(3) This cost is not based on a site specific evaluation.
INCREMENTAL 0 & M COST SUMMARY
ITEM HLND LLND
Maintenance & Materials 2682 5428
Labor 4218 4218
Chemicals 1728 7927
Power ' 8034 8057
SUBTOTAL 16662 25630
TOTAL ANNUAL COST(l) 26363 45261
NOTBS:
(1) Total annual cost is 0 & M cost and annualized capital using
0.1085 capital recovery factor at 8.875 Z interest rate.
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