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November 8, 2011
City of Portsmouth Wastewater Division
Briefing #2 June 11, 2012
WastewaterWastewaterFacilities and ProgramsFacilities and Programs
City Council Briefing and Public Input SessionCity Council Briefing and Public Input Session
Topics for Discussion
• Introduction
• Regulatory Framework and Issues
• Collection System
• Wastewater Treatment Facilities
• Funding
• Questions and Comments
Regulatory Framework and Issues
• NPDES Permit Status
• US House Over-sight Hearing
• Status of Legal Actions
Lincoln Area Contract 3A
Lincoln Area Contract 3B
Cass Street Sewer Separation
Contract 3A - Initial Results S. Mill Pond CSOs
3.45 inches
3.12 inches
Rain
1.28 Million Gallons
June 2, 2012 Storm - After Completion of Contract 3A
2.747 Million Gallons
April 22, 2012 Storm - Before Completion of Contract 3A
CSO Volume
~53% Reduction in CSO volume
Collection System
Collection System
Wastewater Treatment Facility
Wastewater Master Plan – Preferred Alternative
•• Preferred Alternative Preferred Alternative –– Phased Expansion at Pease Phased Expansion at Pease WWTFWWTF
•• EPA/NHDES Response to Draft WMP Preferred EPA/NHDES Response to Draft WMP Preferred AlternativeAlternative– Phased approach does not achieve secondary treatment for Consent
Decree compliance quickly enough– EPA pushing to achieve secondary treatment for Peirce Island flows in
next 5-7 years– Affordability issues do not warrant spreading the project out over 20 years
• Pilot Effort
Piloting Outline
• Initial technology selection
• Pilot description
• Key observations to date
• Pilot timeline
• Key regulatory issues
• Process layouts
• Consent Decree dates
Existing Treatment Process
Outfall To Piscataqua River
Chlorine Contact Tanks
Primary Clarifiers
Grit Chambers
Raw Wastewater
Conventional Secondary Treatment Process
Outfall To Piscataqua River
Chlorine Contact Tanks
Primary Clarifiers
Grit Chambers
Raw Wastewater
Aeration Tanks
Final Clarifiers
Return Activated Sludge
Conventional Secondary Treatment Layout
Nitrogen Removal to 8 mg/l Layout – Sec. Treatment
Pilot Program Goals
• Pilot test the most promising technologies with Portsmouth's wastewater to:
Best meet Portsmouth specific sizing criteria (i.e. fit within fence line of existing plant)
Minimize capital and operational cost
Ability to meet current and future permit limits
Push the technologies to assess how each responds to high flows and loadings
Gain insight into operational requirements and other factors for each technology
Option Evaluation Matrix
Option 1 - BAF
Option 2 - SBR w/
BioMag (Not Feasible)
Option 3 - CAS w/ BioMag
Option 4 - MBBR & ActiFlo
Option 5 - MBBR & CoMag
Option 6 - MBBR & DAF
Option 7 - MBR
Option 8 - Conventional
Activated Sludge
Evaluation Criteria Weight Rating Score Rating Score Rating Score Rating Score Rating Score Rating Score Rating Score Rating Score
Operational Track Record/Established Process 18 3 54 2 36 2 36 1 18 2 36 4 72 5 90Operability (No. of Processes/Complexity of Processes) 22 3 66 3 66 2 44 2 44 3 66 2 44 4 88Ability to Retrofit Conv. Secondary Treatment Meet Future Nitrogen Limits of 8 mg/l 20 1 20 5 100 1 20 1 20 1 20 3 60 4 80Ability to Retrofit TN 8 to Meet Future Nitrogen Limits of 5/3 mg/l 2 5 10 3 6 4 8 4 8 4 8 2 4 4 8Constructability 4 4 16 2 8 4 16 4 16 4 16 3 12 1 4Site Layout Hydraulic Complexity 8 4 32 3 24 4 32 3 24 4 32 4 32 1 8Ability to Stay Within Fence Line for Secondary Treatment 14 5 70 5 70 5 70 5 70 5 70 5 70 1 14Ability to Stay Within Fence Line for Future TN Treatment 4 2 3 3 3 5 1Ability to Treat High FOG Levels 14 3 42 4 56 3 42 3 42 3 42 4 56 3 42Total Weighted Criteria 310 366 268 242 290 350 334Capital Cost (estimated - in millions) $33.0 $37.0 $32.0 $34.0 $32.0 $42.0 $39.0Value Ratio (criteria/capital cost) 9.4 9.9 8.4 7.1 9.1 8.3 8.6Life Cycle Cost (in millions) $40.8 $46.7 $41.2 $47.4 $39.7 $53.3 $46.8Value Ratio (criteria/ life cycle cost) 7.6 7.8 6.5 5.1 7.3 6.6 7.1
BioMag
• Conventional activated sludge with BioMag iron ore (magnetite) ballast that is 5.2 times the weight of water
• Conventional clarification at higher loading rates
• Magnetite feed & recovery equipment
• Proprietary process– Siemens (Formerly Cambridge
Water Technologies)
BAF (Biologically Aerated Filters)
• Upflow packed bed filter
• Treatment and clarification in one vessel
• Backwash required
• Two main vendors: – Kruger: polystyrene media (floats)– IDI: clay shale media (sinks)
Moving Bed Bioreactor
• Media suspended in reactor basin
• No return sludge
• High rate solids separation – Dissolved air flotation
• Many vendors
Pilot Timeline
• Fall 2011 – Secure vendor equipment and construct pilot units
• January, 2012 – Pilot operation start-up
• February Through April, 2012 – Conduct secondary treatment experimental trials
• May/June, 2012 – Conduct nitrogen removal and hydraulic stress test experimental trials
• July through September, 2012 – Analyze data and update Technology Selection Memorandum
• October 1, 2012 – Submit Technology Selection Memorandum to regulatory agencies
Key Observations to Date
Raw Wastewater:
• Influent organic loading variability
• Large component of influent organic loading is in the soluble form
• Influent nitrogen concentrations lower than originally estimated
Raw Wastewater BOD Concentration 2008-2012
Key Observations to Date
Raw Wastewater:
• Influent organic loading variability
•Large component of influent organic loading is in the soluble form
•Influent nitrogen concentrations lower than originally estimated
Key Observations to Date
CAS With BioMag:
• Settling of Magnetite
• Minimize handling of Magnetite
• Requires careful operator attention
Key Observations to Date
MBBR & DAF:
•Biomass Growth Period for Secondary Treatment of about 6-8 Weeks
• Quality Assurance of Media
• Series Reactors
Key Observations to Date
BAF:
•Biomass growth period for secondary treatment of about 3-4 weeks
• Nitrifier growth stage slower than other processes
•System is highly automated
Pilot Experimental Trial StatusPilot Configuration Experimental Trial Status
Secondary BioMag – Average Daily Flow Complete
Secondary MBBR/DAF – Average Daily Flow Complete
Secondary BioMag – Maximum Month Flow Complete
Secondary MBBR/DAF – Maximum Month Flow Complete
Secondary BAF – Maximum Month Flow Complete
Nitrogen Removal to 8 mg/L BioMag – Maximum Month Flow Complete
Nitrogen Removal to 8 mg/L MBBR/DAF – Maximum Month Flow Complete
Nitrogen Removal to 8 mg/L BAF – Maximum Month Flow Pending
Nitrogen Removal to 8 mg/L BioMag – Hydraulic Stress Ongoing
Nitrogen Removal to 8 mg/L MBBR/DAF – Hydraulic Stress Ongoing
Nitrogen Removal to 8 mg/L BAF – Hydraulic Stress Pending
Nitrogen Removal to 8 mg/L BioMag – Nitrogen Stress Pending
Nitrogen Removal to 8 mg/L MBBR/DAF – Nitrogen Stress Pending
Nitrogen Removal to 8 mg/L BAF – Nitrogen Stress Pending
Key Regulatory Questions
Peirce Island WWTF:
• Will Peak Design Flow Be 7.62 MGD or 10.5 MGD ?• Will Total Nitrogen Effluent Limit Be 8 mg/l ?• Will Total Nitrogen Effluent Limit Be A Seasonal Average ?• Will Wet Weather Treatment Train Be Allowed ?
Pease WWTF:
• Will Total Nitrogen Effluent Limit Be 8 mg/l ?• Will Total Nitrogen Effluent Limit Be A Seasonal Average ?• Will An Increase in Flow Through WWTF Outfall Be Allowed ?
The Answer to these Questions Impacts Size and Cost of WWTF Upgrades
Conceptual Facility Layouts
Secondary Treatment Facility Conceptual Layouts
Secondary Treatment Layout – MBBR & DAF
Secondary Treatment Layout - BAF
Secondary Treatment Layout – CAS with BioMag
Conceptual Facility Layouts
Nitrogen Removal to 8 mg/L Facility Conceptual Layouts
Nitrogen Removal to 8 mg/l Layout – MBBR & DAF
Nitrogen Removal to 8 mg/l Layout - BAF
Nitrogen Removal to 8 mg/l Layout – CAS with BioMag
Key Consent Decree Dates
• June 30, 2012 – Complete initial pilot testing
• July 30, 2012 – Submit pilot data
• October 1, 2012 – Submit Piloting Technical Memorandum and recommended secondary treatment capacity
• July 1, 2013 – Commence final design of secondary treatment facilities
• August 31, 2014 – Complete design of secondary treatment facilities
• March 1, 2015 – Commence construction of secondary treatment facilities
• March 1, 2017 – Complete construction of secondary treatment facilities
• May 1, 2017 – Achieve compliance with secondary treatment limits
Funding
• Projected Rate Impacts
• Rate Model RFQ
User Rate Projections User Rate Projections
As Presented June 23, 2010 Public MeetingAs Presented June 23, 2010 Public Meeting
2012 User Rate
Current and Projected Sewer Rates
Billing Unit = 748 gallons or 100 Cubic Feet of water
Cost per Unit
Projected Capital Cost
Current Sewer Rate Lower Tier $ 8.29 Current Sewer
Rate Upper Tier $ 9.11 Projected Sewer
Rate for Secondary Only $ 16.05 $40MProjected Sewer Rate for 3 mg/L
TN $ 20.10 $80M
Water & Sewer Rate Study
• Review and update both water and sewer rate structures and rates (previous rate study was in 2006)
• Assure rate structures promote sustainable water and sewer practices
• Assure equitable sharing of water and sewer costs
• Assure capability to pay for needed improvements and operations
Action Items
• 1.1 - Details on the Maine experience and relationship to New Hampshire issue
• 1.2 - Provide legal and consultant costs for wastewater issues and legal challenge
• 2.1 – Schedule Next Meeting
Action Item 1.2 Coalition Cost Summary
Total Invoiced to Date
Portsmouth Cost
Regulatory Effort $386,800.63 $77,360.13
Memorandum of Agreement
$237,375.00 $47,475.00
Total
Cost Per Year
$124,835.13
$62,417.56
Costs Since June 2010
Questions & Answers
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