Florida’s Class I Water Treatment Injection Wells

Joseph Haberfeld, P.G. UIC Program, FDEP January, 2013

Source: U.S. Geological Survey

Source: elmhurst.edu

0

20

40

60

80

100

120

Municipal RO Blend Industrial Other Hazardous

Num

ber o

f Wel

ls

Class I Injection Wells - 2010

Number of Wells

176 Total Wells

22

108

1 3

26

16

Desalination Facilities in Florida (FDEP, 2009)

WTP/WWTP = Ο WTP = Δ

Blended WTP/WWTP

WTP Only

Class I Desalination Wells

Types of Water Treatment Plants using Injection

• Membrane – mostly Reverse Osmosis (RO)

• Lime Softening • Electrodialysis Reversal (1 plant) • Nanofiltration

Injection Well

g

Anhydrite

Base USDW

Injection Zone

Brackish Ground Water

Potable Ground Water

Sy

Injection Zone

Injection Zone

Peninsular Florida Tertiary Stratigraphy

RO Injection Wells in Sarasota County, Florida: The Early Years

W E

Venice Gardens Plantation Englewood

Avon Park Formation Injection Zone

1000

ft

SL

Albert Whitted WRF Generalized Pre-Injection (Background) Water Quality

Profile

Depth in Feet

0

200

400

600

800

1,000

1,200 Concentration expressed in mg/L (CH2M HILL, March 1993)

TDS > 35,000

TDS 10,000 - 35,000

TDS 3,000 - 10,000

TDS < 3,000

East IW-2 MW-1 MW-2

MW-3 West IW-1 Hydrogeologic Unit

General Formation/ Lithologic

Surficial Sands

Peace River Formation

Tampa Member of Arcadia Formation

Aquitard Suwannee Limestone

Water Bearing Zone

Avon Park Formation

Aquitard

Injection Zone

Aquitard

Surficial Aquifer

Ocala Limestone

A

B

C

Upp

er Fl

orid

an A

quife

r H

awth

orn

Gro

up

Water Bearing Zone

Aquitard

Zone

Chemistry of Wastewater vs. Injection Zone Water

Municipal RO Injection Parameter Wastewater Concentrate Zone Chloride 100 mg/L 1500-6000 19,000 Sulfate 100 mg/L 1000-2000 2,000 Total Dissolved 500mg/L 3000-20,000 35,000 Solids pH 7 std units 7 7 Gross Alpha <15 pCi/L 20-300 >15 Total Nitrogen 20 mg/L 2-4 <2 Specific Gravity 1.000 g/cc 1.004-1.01 1.025

Operating Conditions of a WTP Injection Well in South Florida

Injection into “Boulder Zone”

Very high Transmissivity – >1 mgd/ft or 134,000 ft2/d

Volumes – Up to approximately 2 MGD

Very low wellhead pressure - < 20 psi; can be < 5 psi

WTP concentrate may be combined with WWTP effluent

Increased volumes and injection pressures

One to two wells per site

TYPES OF TUBING MATERIAL

MILD STEEL

EPOXY-COATED STEEL

ACRYLONITRILE-BUTADIENE-STYRENE (ABS)

FIBERGLASS REINFORCED PLASTIC (FRP)

DUPLEX STAINLESS STEEL

Source: Future Pipe Industries

Factors Affecting Corrosion of Tubing and Packers

Salinity of Injectate

Tubing Material

Packer Material

Packer Design

Dissolved Oxygen in Injectate

Injection Rates

TYPES OF PACKERS

MECHANICALLY SET, CONVENTIONAL TYPE

(SUCH AS TIW) - removable “POSITIVE-SEAL” TYPE – non-removable

Positive Seal Packer

HOW TO FIX AN ANNULAR LEAK

Hope it goes away

Tighten/repair all surface connections

Place seal (bentonite, barite) on top of packer

Replace annular fluid with a special mixture to seal leak

Replace tubing and/or packer, refill annulus with fluid

Completely cement annular space

Cemented Tubing

Cemented Annulus

Cemented Final Casing

Tubing

Packer

Casing Cemented Intermediate

Injection Zone

Base USDW

Alternative Design, Older Well Double-Cased To Injection Zone

Another cemented casing (non-steel)

Casing

(steel)

Cemented

Cemented casing (steel)

Injection Zone

Required Monitoring at Class I WTP Sites: Field Temperature (deg. C)

pH (std. units) Specific Conductance (µmhos/cm)

Chloride (mg/L) Sulfate (mg/L)

Total Dissolved Solids (mg/L) Sodium (mg/L) Calcium (mg/L) Potassium (mg/L)

Magnesium (mg/L) Bicarbonate (mg/L) Iron (mg/L)

Total Kjeldahl Nitrogen (mg/L) Gross Alpha (pCi/L) Radium 226 (pCi/L) Radium 228 (pCi/L)

Vertical Fluid Monitoring

Depth in Feet

0

200

400

600

800

1,000

1,200 Concentration expressed in mg/L (CH2M HILL, March 1993)

TDS > 35,000

TDS 10,000 - 35,000

TDS 3,000 - 10,000

TDS < 3,000

East IW-2 MW-1 MW-2

MW-3 West IW-1 Hydrogeologic Unit

General Formation/ Lithologic

Surficial Sands

Peace River Formation

Tampa Member of Arcadia Formation

Aquitard Suwannee Limestone

Water Bearing Zone

Avon Park Formation

Aquitard

Injection Zone

Aquitard

Surficial Aquifer

Ocala Limestone

A

B

C

Upp

er Fl

orid

an A

quife

r H

awth

orn

Gro

up

Water Bearing Zone

Aquitard

Zone

0

5000

10000

15000

20000

25000

30000

35000

7/1/1997 7/1/1998 7/1/1999 7/1/2000 7/1/2001 7/1/2002 7/1/2003 7/1/2004 7/1/2005 7/1/2006 7/1/2007 7/1/2008

North Miami Dade Mon Well FA2N Zone B TDS

Series1

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2

4

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12

14

7/1/1997 7/1/1998 7/1/1999 7/1/2000 7/1/2001 7/1/2002 7/1/2003 7/1/2004 7/1/2005 7/1/2006 7/1/2007 7/1/2008

North Miami Dade Mon Well FA2 Zone B TKN

Series1

Contact Information

Joe Haberfeld

Florida Department of Environmental Protection

2600 Blair Stone Road, MS 3530

Tallahassee, FL 32399-2400

Phone: 850-245-8655

Email: joe.haberfeld@dep.state.fl.us