Water-Quality Changes During ASR Cycle Tests, South Florida

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Water-Quality Changes During ASR Cycle
Tests,South Florida
June Mirecki, Ph.D. US Army Engineer Research
Development Center Waterways Experiment
Station Vicksburg, Mississippi
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Objectives

• TO USE EXISTING WATER QUALITY DATA AS A
• GUIDE FOR CERP ASR PILOT SITES

• Requires collating water-quality data sets
  obtained
• during ASR cycle tests at permitted facilities in
  South Florida

• Enables interpretation of water-quality changes
  that result from
• geochemical reactions in the Upper Floridan
  aquifer

Olga (Lee County) WTP - 5 MGD well
West Palm Beach County well field
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South Florida ASR Sites

• Lee and Collier Counties
• Olga
• North Reservoir
• Ft. Myers Winkler Ave
• Corkscrew
• Bonita Springs San Carlos Estates
• Marco Lakes

• Palm Beach and Broward
• Counties
• Boynton Beach
• Delray Beach
• BCOES 2A WTP
• Fiveash WTP
• Springtree City of Sunrise

Redrawn from Reese (2002)
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Water-Quality Data

• Water-quality analyses were performed at NELAP-
  and/or
• Florida DOH-certified laboratories

• Water-quality analytes were measured to fulfill
  permit
• requirements, not geochemistry.

• Data sources include FDEP Monthly Operating
  Reports, consultants reports, and records
  compiled by WTP operators
• Data sets vary extensively in number and type of
  analytes measured.

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Ideal Water-Quality Data Set

• Complete Water-Quality Analysis
• CATIONS Calcium, Magnesium, Sodium,
  Potassium,
• ANIONS Chloride, Fluoride, Sulfate, Carbonate
  Alkalinity
• WQ PARAMETERS pH, Specific Conductance
• Regulatory Species Gross Alpha, Radium
  228226, Total Trihalomethanes, Arsenic
• Metals Dissolved Iron, Manganese
• Redox State Indicators Dissolved Hydrogen
  Sulfide, Dissolved Oxygen

Analysis of samples from ASR and Monitoring Wells
Analysis of samples obtained during Recharge,
Storage, and Recovery
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Important Water-Quality Changes

• Increased Gross Alpha and radium
• isotope activity in recovered water due
• to mixing between native and recharged
• water

• Arsenic mobilization due to pyrite
• oxidation, a water-rock interaction

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(No Transcript)
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Trends in Gross Alpha Activity
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Gross Alpha and Radium Isotope Activity During
Cycle Tests Lower East Coast
MCL
MCL
Low natural radioactivity in Avon Park Formation
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Gross Alpha and Radium Isotope Activity During
Cycle Tests Southwest Florida
MCL
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Southwest Florida ASR Sites
Elevated natural radioactivity is associated with
phosphate-rich lithologies of Lower Hawthorn
Group and Suwannee Formation
Well log, L-5812, Bonita Springs. Figure 18 in
Reese (2002)
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Mechanism for Preferential Release of Radium
Isotopes from Phosphate
Preferential dissolution along grain defects
releases radium to native ground water
From Rama and Moore (1984)
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Trends in Arsenic Concentration
MANY DATA GAPS
MCL
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Arsenic Concentration Trends During Cycle Tests
Southwest Florida
Microcrystalline pyrite (iron sulfide) is
oxidized by recharge water, releasing arsenic
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Mechanism of Arsenic Mobilization Pyrite
Oxidation
10 µm
10 µm
Figure 4. Backscatter electron images of Suwannee
Limestone, Floridan aquifer system. White areas
are pyrite occurring as A - finely disseminated
intergranular and intragranular subhedral
crystals (Rome Avenue, ASR 3, 255 feet below land
surface), and B - framboidal masses along pore
spaces within carbonate matrix (Rome Avenue, ASR
5, 251 feet below land surface). From Arthur et
al. (2001)
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Conclusions

• Elevated natural radioactivity (gross alpha,
  radium
• 226228) occurs in recovered water at southwest
  Florida ASR
• systems due to mixing. Continuous data are
  needed
• through a cycle test at Lower East Coast ASR
  systems
• Arsenic is mobilized by pyrite oxidation.
  Elevated arsenic
• concentrations occur when storage zone is within
  the
• Lower Hawthorn Group. Readily observed in
  southwest
• Florida, more data are needed for Lower East
  Coast systems.

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Matters Arising

• New monitoring requirements for uranium and
  210Po. New
• data may clarify variations in gross alpha
  measurements
• Other metals in pyrite may be mobilized during
  ASR
• cycle testing. Mercury?
• Complete water-quality analyses will enable
  better
• interpretations. Please analyze through the
  entire cycle test,
• and preferably cycle 1 and during a later cycle.

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Mr. Peter Mazzella, City of Boynton Beach ASR
System Dr. Thomas Missimer, CDM/Missimer
International, Fort Myers Dr. Kirk Martin,
CDM/Missimer International, Fort Myers Mr.
John Cargill, C.E. Fiveash Regional WTP, Fort
Lauderdale Mr. Bill Beddow, CH2MHill,
Tampa Mr. Mark McNeal, CH2MHill, Tampa Mr.
Steve Gong, CH2MHill, Deerfield Beach Mr.
n'Detenga n'Gurumo, Delray Beach Environ.
Services Laboratory Mr. Doug Stryjek, Delray
Beach Water Treatment Plant Mr. Richard Orth,
Florida DEP, Fort Myers Mr. Joe Haberfeld,
Florida DEP, Tallahassee Mr. Joe May, Florida
DEP, West Palm Beach Mr. Len Fiskin, Florida DEP,
West Palm Beach Mr. Paul Mattaush, Manatee Road
ASR, Collier County Mr. Peter Schalt, Manatee
Road ASR, Collier County Mr. Howard Brogdon,
Manatee Road ASR, Collier County  Mr. Clint
Oakley, Miami-Dade Water and Sewer
Department  Mr. Ronald Reese, US Geological
Survey, Miami  Mr. Lloyd Horvath, Water Resource
Solutions, Inc., Coral Springs, FL Dr. Dan
Acquaviva, Water Resource Solutions, Inc. Coral
Springs, FL
THANK YOU FOR YOUR HELP!