An industry update on nitrogen removal programs across the United States. Presented by Rick Cisterna, Senior Associate with Hazen and Sawyer during the Buzzards Bay Coalition's 2011 Decision Makers Workshop series. Learn more at www.savebuzzardsbay.org/DecisionMakers

1. Industry Update on Nitrogen Removal
Programs Across the United States:
What Does it Mean for New England?
March 3rd, 2011
Richard H. Cisterna, P.E.
Cisterna, P.E.
1

2. Outline
1
Water Industry Sustainability
2
National Perspective - Nitrogen and Hypoxia
3
Massachusetts Estuaries
Nitrogen Treatment Technology Overview
4
5
Conventional and Advanced
Case Studies
6
2
Summary and Conclusions

3. Water Industry Sustainability
3

4. Sustainability is in Vogue
4

5. Focus of Sustainability has been on Energy
● Energy Audits
● Energy Optimization
● Renewable Energy
Sources
5

6. Sustainability Balancing Act
Nitrogen
Water Supply /
Wastewater Effluent
Green Energy
Carbon Footprint
6

7. National Perspective on
Nitrogen and Hypoxia
7

8. Nitrogen is an Emerging National Concern
8

9. Nitrogen’s Impact on the Ecosystem
Source: evworld.com
9

10. Chesapeake Bay Oxygen Depletion
Source: evworld.com
10

11. Long Island Sound Nitrogen Control Program
● In 1998, CT, NY, and EPA agreed to reduce
human sources of N by 58.5% by 2014. A
TMDL was developed and approved by EPA
in 2001.
11

12. Long Island Sound
12
Source: CTDEP and Long Island Sound Study

13. The Mississippi River Carries A lot of Nitrogen
13

14. And the Gulf of Mexico Pays the Price…
Source: evworld.com
14

15. Historical Development of Nitrogen Limits
10
9
Chesapeake Bay
Long Island Sound, NYC
8 mg/l
8
7
TMDL
(mg/l)
6
Long Island Sound, CT
North Carolina
5 mg/l
5
4
3 mg/l
3
2
1.5 mg/l
1
Florida
0
1990
15
2000
2010
2020

16. Massachusetts Estuaries
16

17. Mass Estuaries also have nitrogen concerns
17

18. Mass Nitrogen Reduction Program Goals
» Reduce ‘N’ to estuaries
» Consider centralized and decentralized
approaches
» Highly treat wastewater to new
Massachusetts DEP Standards
» Strategically recharge reclaimed water
18

19. Western Cape Recharge Basins
Source: USGS
19

20. Mass. DEP: Groundwater Discharge Program
(314 CMR 5.00)
Requirements

Meet secondary treatment effluent limits:
» Nitrate as Nitrogen < 10 mg/L
» Total Nitrogen
< 10 mg/L
» Fecal Coliform
< 200 colonies per 100 mL
All Discharges

Discharges within
Zone II or IWPA
Effluent shall be filtered to meet:
» TSS
» Turbidity
» TOC

Discharges within
Zone II or IWPA
and 2 year Travel
Time
< 10 mg/L
< 5 NTU
< 3 mg/L
Effluent shall be oxidized, filtered, disinfected and coagulated
to meet:
» TSS
» Turbidity
» BOD
< 5 mg/L
< 2 NTU
< 10 mg/L
» TOC
< 1 mg/L
» Fecal Coliform
= avg. of zero colonies per 100 mL over a
continuous 7 day sampling period; no single
sample shall exceed 14 colonies per 100 mL
= 5 Log Inactivation and/or Removal
or
20
Direct Injection
(into saturated
zone)
» Virus

Disinfection shall not be waived.

Coagulation may be waived if meet turbidity requirement with
filtration alone.

21. Treatment Approaches?
● Decentralized Advanced Septic Systems
● Biological Treatment
● Centralized MF/RO, (AOP?) – Concentrate Issue
● MF, GAC, (AOP?)
21

22. Regulations for Indirect Potable Reuse
Florida
Mass.
10 ppm*
10 ppm*
5 ppm
10 ppm
1 ppm
TOC
3 ppm
3 ppm
1 ppm
0.5 ppm
---
1 ppm
Emerging
Contaminants
No/Yes
No?
Yes
No/Yes
Yes
Nitrogen
California Arizona
* Local requirements can be more stringent
22
Australia

23. Nitrogen Treatment
23

24. Nitrification / Denitrification Activated
Sludge Process - MLE
TKN = 30 mg/L
TP = 7 mg/L
Aeration Tanks
3Q
Pretreated
Wastewater
Primary
Clarifiers
NH3-N < 2 mg/L
NO3-N < 5 mg/L
TN = 8 mg/L
TP = 5 mg/L
Secondary
Clarifiers
Anoxic
Air Blowers
Secondary
Effluent
Aerobic
Return Sludge
Primary
Sludge
Waste Activated
Sludge
N&P Removal
● Solids in primary sludge (5 - 10 %)
● Biosynthesis in WAS (10 - 20 %)
● Denitrification (40 - 60 %)
24
TN ~ 8 to 10 mg/L

25. BNR Step Feed Configuration
TWO-STEP FEED PROCESS
Step Feed
Secondary
Clarifiers
Pretreated
Wastewater
Anoxic
Aerobic Anoxic
Secondary
Effluent
Aerobic
RAS
TN ~ 6 to 9 mg/L
Waste Activated
Sludge
FOUR - STEP FEED PROCESS
Secondary
Clarifiers
Pretreated
Wastewater
Secondary
Effluent
Anoxic Aerobic Anoxic Aerobic Anoxic Aerobic Anoxic Aerobic
RAS
25
TN ~ 4 to 6 mg/L
Waste Activated
Sludge

26. BNR Process Configurations – 5-stage
Typical 5-stage BNR Process – Lower TN limit
Carbon
Secondary
Clarifier
Wastewater
Anaerobic Primary
Anoxic
Aerobic Secondary
Anoxic
BNR
Aeration Tank
Secondary
Effluent
Reaeration
WAS
TN ~ 3 to 4 mg/L
26

27. 3+ Stage with Denitrification Filters
TN < 3 mg/L
Acetate
Methanol
Secondary
Clarifier
Wastewater
Anaerobic Anoxic
Aerobic
BNR
Aeration Tank
WAS
27
Granular
Media
Filter
Secondary
Effluent

28. Denitrification Filters
● Nitrified secondary effluent sent to filtration
● Filter media used to grow an attached biomass that
will denitrify the secondary effluent
● Supplemental carbon addition
● Good solids removal + denite – 2 gpm/ft2
28

29. Membrane Bioreactor (MBR)
Typical MBR Process
29

30. Integrated Fixed Film Activated Sludge
(IFAS)
● Media held in Aeration Basins to provide
attached growth for Nitrifying biomass
● Typical Floating and Fixed IFAS Media
» Kaldnes (plastic)
» Linpor (sponge)
» Ringlace (cord)
30
30

31. IFAS in Nutrient Removal
ANA
ANOX AEROBIC
•Higher capacity in same
volume
•“Modular” phasing
•Improved wet weather
stability
31
ANOX

32. TZ Osborne WRF – Pilot Layout
RAS
To Final
Clarifier No. 7
Primary
Effluent
IFAS
Cell 1
~ 35% fill (AK-K3)
3 distinct zones
32
IFAS
Cell 2
IFAS
Cell 3
Screens for each cell
Isolation / throttle air
valve for each cell

33. IFAS Pilot Results / Lessons Learned
● Effective nitrification in
approximately half the
aerobic volume
● Dynamic microbial
population
● Higher air usage
● Screen headloss higher than
expected
● Foam handling a must
● Influent screening must be
sized correctly (i.e. opening
size)
33
Biomass on Media (gTSS/m2 of media surface)
30
25
20
15
10
5
0
04/01/08
06/13/08
08/25/08
11/06/08
01/18/09
04/01/09
Date
Cell D Biomass
Cell E Biomass
Cell F Biomass

34. BioMag
From CWT Website http://cambridgewatertech.com/technology/biomag
34

35. Typical Process Treatment Train for Ultra-Low
UltraNutrient Standards
35

36. Cost vs. Nitrogen Removal
Cost ($)
Nitrogen Removal (mg/L)
36

37. Nitrogen Removal Option Summary*
2-Stage
BNR
4/54/5-Stage
BNR
+ Carbon
Feed
4/54/5-Stage
BNR
+ Denite
Filters
4/5-Stage
4/5BNR
+ MBR w/
Carbon Feed
4/5-Stage
4/5BNR
+ UF + NF or
RO
TN effluent
Achievable
8 - 12 mg/L
3 - 6 mg/L
3 - 4 mg/L
2 - 3 mg/L
< 1.5 mg/L
Capital Cost
per GPD
$0.25 - $1.25
$0.50 - $2.00
$1.25 - $2.50
$2.50 - $3.00
$3.00 - $4.00
40 kW
50 kW
55 kW
100 kW
125 kW
$21k - $28k
$30k - $40k
$35k - $47k
Criteria
Energy
Usage per
MGD
Annual O&M
Cost per
MGD
$121k - $161k $261k - $348k
*Relative cost for additional treatment only. Total cost will depend on the available plant infrastructure.
37

38. Supplemental Carbon
38

39. Available Supplemental Carbon Sources
● Methanol
● Ethanol
● Acetic acid
● Corn syrup/sugar
● Glycerin
● MicroC™
● Primary fermentate
39

40. Methanol Considerations
● Benefits
» Low cost (relative to alternatives)
» Low yield (low solids production)
» Proven technology
● Drawbacks
» Requires specialist population
■ Slow growing
» Volatile price
» Slower kinetics
» Flammable
40
Recent Methanol Accident Site at
Bethune Point WWTP

41. 41
www.methanex.com
Mar-09
Sep-08
Mar-08
Sep-07
Mar-07
Sep-06
Mar-06
Sep-05
Mar-05
Sep-04
Apr-04
Oct-03
Apr-03
Oct-02
Apr-02
Oct-01
Apr-01
Methanol Price ($/Gallon)
Methanol Costs – 2001 to 2009
(Expect Price Fluctuations)
$3.00
$2.50
$2.00
$1.50
$1.00
$0.50
$0.00

42. Glycerin
● Typically byproduct of
biodiesel production
● Benefits
» Faster kinetics
● Drawbacks
» Potential for product
inconsistencies with
waste products
» Viscous in cold weather
» Specialist population not
required
● Products
» Brenntag
» Unicarb-DN
» BioCarb DN (Denite-1)
» MicroC-Glycerin
» Waste products
42

43. Alternative Carbon Testing
Parameter
NRWWTP
HCWRF
Size (mgd)
Feed point
Basins fed
carbon
Control
(if
applicable)
75
75
One
All
Substrate
43
PWWTP
SDWRF
NDWRF
7.5
Second anoxic zone
All
20
20
One
4 out of 5
One parallel Full-scale
Full-scale One parallel One parallel
basin that
evaluation, evaluation,
basin that
basin that
was fed
therefore no therefore no was not fed was not fed
methanol
control
control
carbon
carbon
Glycerin
Sugar water
Glycerin
Glycerin
Glycerin
and glycerin

44. Parkway WWTP
CHLORINE
CONTACT
BASINS
INFLUENT PUMP
STATION
RAS
PUMP
STATION
SECONDARY
CLARIFIERS
BNR BASIN #2
(RB2)
GRIT
REMOVAL
PRIMARY
CLARIFIERS
BNR BASIN #1
(RB1)
SOLIDS HANDLING
44
MLR PUMP
STATION

45. Parkway Full-Scale Pilot Data
Full■ No Acclimation Period Required
Full Scale Pilot Data
1/26/2008
1/19/2008
1/12/2008
45
Effluent NOx
Effluent TN
Brenntag Glycerin
7 per. Mov. Avg. (Effluent NOx)
7 per. Mov. Avg. (Effluent TN)
Carbon dose, gal/day
0
1/5/2008
0
12/29/2007
20
12/22/2007
1
12/15/2007
40
12/8/2007
2
12/1/2007
60
11/24/2007
3
11/17/2007
80
11/10/2007
4
11/3/2007
100
10/27/2007
120
5
Concentration (mg/L)
6

46. Cell
1
Cell 2
Cell 3
3848-047
Primary
Anoxic/
Aerobic Zone
Cell 4
Cell 5
Secondary
Anoxic/
Aerobic Zone
Aerobic Zone
Cell 6
Cell 7
Cell 8
R
eAeration
Zone
Prim
ary
A
noxic/
Anaerobic Zone
Anaerobic
Zone
RA
S
Ferm
entation
Henrico VA
Cell 9
Cell 10
Cell 11
Cell 12
Cell 13
NRCY
RAS
M istributionC
LD
hannel
PED
istributionChannel
RA
SPipeline
BNR Tank 8
NRCY
RAS
BNR Tank 7
NRCY
RAS
BNR Tank 6
NRCY
RAS
To
Secondary
Clarifier
No. 8
BNR Tank 5
ML Distribution Channel
RAS/WAS
Pump Station
RAS
46
To
Secondary
Clarifier
No. 7

47. Henrico County WRF Plant Effluent Nitrogen
Profile vs. Substrate Feed Rate
● Sugar water and glycerin both effective.
47

48. North Carolina “Conventional”
Case Studies
48

49. Neuse River WWTP, Raleigh, NC
● 60 mgd Advanced WWTP
» Primary Clarifiers
» 4-stage BNR w/ methanol
addition
» Denitrification Filters w/
methanol addition
● Largest Plant in Eastern U.S.
Achieving LOT for TN Utilizing
Conventional Suspended Growth
BNR Process
● Upcoming Expansion to 75 mgd
» TN = 2.7 mg/L, TP = 1 mg/L
● Calibrated BioWin Model Used to
Evaluate/ Optimize Expansion
49

50. Neuse River –
4-stage w/ denitrification filters
Typical Operating Parameters
50

51. Neuse River - Operation and Performance
● Most TN Removal in BNR Basins
● Filters “Trimming” ± 1 mg/L (~ 5 mg/L Methanol Dose)
● Annual Average Effluent TN = 2.4 mg/L (2004 - 2008)
S E a n d F in a l E fflu e n t N itr o g e n C o n c e n tr a tio n s
6
● 2007 Annual Average Effluent TN = 1.96 mg/L
Concentration (mg/L)
5
4
3
2
1
EFF TN
SE TN
3 0 p e r. M o v . A v g . (E F F T N )
3 0 p e r. M o v . A v g . (S E T N )
Sep-07
Jul-07
May-07
Mar-07
Jan-07
Nov-06
Sep-06
Jul-06
May-06
Mar-06
Jan-06
Nov-05
Sep-05
Jul-05
May-05
Mar-05
Jan-05
Nov-04
Sep-04
Jul-04
May-04
Mar-04
51
Jan-04
0

52. High Point, NC – 26 mgd, 5-stage process
mgd, 5-
52

53. 53
EFF TN
No alum or ferric
10/29/2008
7/31/2008
5/2/2008
2/2/2008
11/4/2007
8/6/2007
5/8/2007
2/7/2007
11/9/2006
8/11/2006
5/13/2006
2/12/2006
11/14/2005
20
8/16/2005
5/18/2005
2/17/2005
11/19/2004
8/21/2004
5/23/2004
2/23/2004
11/25/2003
8/27/2003
5/29/2003
2/28/2003
11/30/2002
9/1/2002
EFF Total Nitrogen (mg/L)
High Point Performance
22
Average Eff TN 1/07 to 12/08 = 3.3 mg/L
18
16
14
12
No supplemental
carbon
10
8
6
4
2
0
30 per. Mov. Avg. (EFF TN)
Avg TP = 0.18 mg/L Biologically

54. Major Recycle Impacts
● Solids handling recycle streams
» Filtrate, centrate, gravity thickener
overflow
● Frequency of return
Parameters
Plant Recycle Loads
(lbs/day)
Contribution From
Plant Recycles
(%)
BOD
43,600
2,830
6.5
TSS
39,300
6,590
17
TKN
54
Plant Influent Loads
(lbs/day)
5,700
1,620
29
TP
1,280
680
53

55. Florida “Advanced”
Case Studies
55

56. Florida vs. Mass Estuary Nitrogen Challenge
● FL - Existing Ocean Outfalls and Septic Tanks
● Cape – Mostly Septic Tanks
● Both – High Level Nitrogen Treatment / Recharge
56

57. Historically, South Florida’s sole source supply
(the Biscayne Aquifer), was fiercely protected
Effluent
Reuse
Class I
Deep Injection Wells
57
Two Key issues for FDEP:
● Alternate Water Supply
Resource
● Environmental
enhancement (Nitrogen)

58. Existing Supply Limited for Utilities
C.E.R.P
No New Water
for the Public
58

59. Recent Legislation – Ocean Outfall Ban
● Outfall shut down due to nitrogen – Coral Reefs
● Achieve significant TN & TP reductions by 2018
● “Reuse” 60% of outfall flow by 2025
● After 2025, outfall for wet weather back-up, w/
nutrient reductions
59

60. Legislated Water Reuse Requirements
Lake
Okeechobee
7.7 MGD
6.2 MGD
22.4 MGD
24.1 MGD
48.6 MGD
68.9 MGD
Total = 178 MGD
60
South Central Regional
Boca Raton
Broward Co. North
Hollywood
Miami-Dade North
Miami-Dade Central District

61. Recharging Groundwater is Essentially a Surface
Water Discharge – nitrogen concerns
County / Local Issues
61

62. Miami Dade County
62

63. Miami South District
Water Reclamation Plant
● 1st indirect potable reuse project in Florida
● Recharge drinking water aquifer with 23 mgd of
highly treated wastewater
● Addressing pharmaceuticals and pathogens with
regulators and public
● MF, RO, UV-AOP
● Ultra-pure drinking
water quality
63

64. Emerging Contaminants
Pharmaceuticals
Personal
Care Products
64
Endocrine
Disrupting Compounds

65. Advanced Oxidation Processes (AOPs)
High dosage UV w/ H2O2
UV ~ 500 mj/cm2
H2O2 ~ 1-3 ppm
UV – TiO2
Ozone
65

66. Hydroxyl Radical (OH°) is a very strong oxidant!
OXIDIZING SPECIES
RELATIVE OXIDATION
POTENTIAL (V)
Hydroxyl Radical
2.05
Ozone
1.52
Hydrogen Peroxide
1.31
Permanganate
1.24
Chlorine Dioxide
1.15
Chlorine
1.00
Data from Metcalf & Eddy, 2003
66
Increasing
ability to
degrade
pollutants

67. Miami Dade South District WRP
Miami-Dade County
Miami-
67

68. Example of the complexities
Moat
Drainage Canal
Regional Canal
Proposed
Biscayne Wells
68
Note: Locations are conceptual. Intended for discussion purposes only

69. Biscayne National Park is Environmentally
Sensitive
69

70. Groundwater Recharge Criteria
Miami Dade
County
Florida
State
Standard
TOC
--
3 mg/l
Total Suspended Solids (TSS)
--
5 mg/l
Total Nitrogen (TN)
--
10 mg/L
Ammonia
2.8 mg/l
0.5 mg/l
--
Total Phosphorus (TP)
.003 mg/l
--
Yes
No
Parameter
Emerging Contaminants
70

71. Precedent Setting Treatment Levels
71

72. Plantation, FL Pilot Study
72

73. WWTP Located Near Canal That Could
Recharge the Biscayne Aquifer
Plantation
WWTF
East Holloway
Canal
East
Wellfields
Central
Wellfields
73

74. Pilot Goals
● Demonstrate technology
can meet water quality
» TN
» TP
● Unregulated Parameters
» Microconstituents
» Toxicity
» Algal growth potential
» Hormonal impacts
74

75. Things to consider
75

76. Nutrient Control
● What is the
technology
necessary to meet
the stringent TN &
TP limits?
● Biological vs
Chemical nutrient
removal
● Are RO
membranes
necessary?
76

77. Aquatic Organism Impact
● Whole effluent
toxicity (WET)
tests
● Is the RO
permeate toxic?
● Will the effluent
cause any
hormonal
impacts?
77

78. Microconstituents
● Which
microconstituents are
in your wastewater?
● What technology will
most effectively
remove them?
● Are
microconstituents
really a concern at
these concentrations
(ng/L)?
78

79. Recharge Modeling
● Does your
point of
discharge “offset” your
withdrawal
impacts?
● Can you get a
1/1 credit?
● What happens
during the wet
season?
79

80. Sustainability
● Is this really
sustainable?
● Water Supply
vs Carbon
Footprint?
80

81. Public Outreach
● How do you
change the “Sewer
to Tap” mentality?
● How do you
involve the public
early in the
project?
81

82. Costs
● Capital cost
● Energy costs
82

83. Plantation Pilot
83

84. Broward County
Canal Recharge Effluent Limits
Parameter
Effluent Limit
TN
< 1.5 mg/L
TP
< 0.02 mg/L
Nitrate
< 10 mg/L
Ammonia
TSS
< 5.0 mg/L
CBOD5
< 10.0 mg/L
BOD
84
< 0.02 mg/L
< 5.0 mg/L

85. MBR Scheme
85

86. Conventional Treatment Scheme
86

87. MBR Scheme Data
87

88. Plantation AWT MBR Scheme
MBR Pilot
88
RO/UV
Pilot Trailer

89. Total nitrogen removal of
MBR and RO Pilot Units
89

90. Total phosphorus removal of
MBR and RO Pilot Units
90

91. Conventional Treatment Data
91

92. Plantation AWT Conventional
Treatment Scheme
Denitrification
Filter Pilot
92
UF/RO/UV
Pilot Trailer

93. Total nitrogen removal of
Deep Bed Filter and RO Pilot Units
93

94. Total phosphorus removal of
Deep Bed Filter and RO Pilot Units
94

95. Conclusions – Nutrient Removal
● Both pilots met stringent TN & TP limits
● RO membranes are necessary to meet TP limit
● Membranes alone (UF/RO) with no chemical
addition met TN & TP limits
95

96. Microconstituents
96

97. What are Microconstituents?
● Pharmaceutically Active Compounds (PhAC)
» Ethynyl Estradiol
» Sulfamethaxazole
● Personal Care Products (PCP)
Ethynyl Estradiol
» Triclosan
» Toiletries, cosmetics, fragrances
● Endocrine Disrupting Compounds (EDC)
» Bisphenol-a
» Atrazine
» DEET
97
DEET
Triclosan

98. Concentration (ng/l)
Microconstituents –
RO Influent Concentrations
98

99. Concentration (ng/l)
Microconstituents – Most were
removed by RO membranes
99

100. Aquatic Organism Toxicity Testing
100

101. Is the RO permeate toxic?
● RO permeate is too clean
» RO re-stabilization/re-mineralization
» Added salts and minerals
● How would this work full scale?
» Dilution
» Mixing zone
101

102. Does RO Pre-treatment
Preaffect toxicity?
● RO Pre-treatment
» Antiscalant
» Chloramines
● Pilot Results
Fatheaded Minnow
102
Water Flea

103. Summary
● The pilot demonstrated to meet stringent nutrient
limits at different test conditions.
● RO membranes are necessary for surface water
discharge due to stringent TP limits.
● Almost all microconstituents were removed by
RO system.
● RO permeate could be toxic re-stabilization/remineralization is necessary.
● The observed toxicity to aquatic organisms was
likely caused by chloramines. Other forms of RO
pretreatment should be evaluated.
103

104. University of Connecticut
Advanced Reuse Project
104

105. University of Connecticut Reuse Project
105

106. This is a Spotlight Project
106

107. Potential Uses of Reclaimed Wastewater
Reuse
Facility ►
▼ WWTP
◄ Power Plant
107
◄ Irrigation Sites ►

108. Process Flow Diagram
108

109. UCONN Reclaimed Water Facility
University of Connecticut
– Reclaimed Water Facility
Location
Storrs, CT
Capacity
1.0 mgd
Technology
Microfiltration +
UV Disinfection +
Chloramination
Application
• Cooling Tower
Make-Up Water
• Boiler Feed Water
(post RO treatment)
• Irrigation
Unique
Challenges
109
• Corrosion &
Scaling Control for
Cooling Towers

110. MF System Design Criteria
Parameter
Type
Pressurized
System Rated Capacity
1 mgd
No. of MF Units
3
No. of Membrane Modules per Unit
32
Membrane Type
0.1 micron PVDF
Specific Design Flux
39 gfd
Minimum Recovery Percent
110
Value
91%

111. UV System Design Criteria
Parameter
Type
LPHO
System Rated Capacity
1 mgd
No. of UV Systems
2+1
UV Design Dose
80 mJ/cm2
UV Transmittance
≥ 65% at 254 nm
Effluent Turbidity
≤ 0.2 NTU (95% of the time)
Effluent Total Coliform Max.
2.2/100 mL (7 day geometric mean)
Suspended Solids Max.
111
Value
5 mg/L

112. Sustainability Features
● Replaces as much as
40% of water supply at
times
● Reclaimed water
reservoir used as a
heating source
● Stormwater capture and
blending with wastewater
● Solar electricity
112

113. Constructed New Facility?
113

114. Summary and Conclusions
114

115. Summary and Conclusions
● Nitrogen control programs are growing
● Very low nitrogen requires significant energy and $
● Range of treatment options
● Good experiences and resources in other states to
draw upon
115