Chickadee Remediation Company

TEXAS

8810 Will Clayton Parkway,

Suite J

Humble,

Texas  77338

Phone:  281-540-8711

Fax:  281-540-3893

MONTANA

7801 York Road

Helena,

Montana  59602

Phone:  406-475-3430

Fax:  406-475-3801

 

Contact Us

CALIFORNIA

5200 Warner Avenue,

Suite 207

Huntington Beach,

California  92649

Phone:  714-840-8036

Fax:  714-840-6843

               

 

 

Site Remediation

Management Program

The key issues in managing contaminated sites are:

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Status of potential pathways

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Receptor protection

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Source identification and control

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Nature and extent of soil, groundwater, and vapor impacts

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Physical characteristics of the subsurface

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 Properties of the chemicals present in the soils and groundwater

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Timely, cost-effective, and environmentally-sound remedial action

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Develop/implement the appropriate technology sequence

 

Site Assessment

Basic Objectives

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Define the nature and extent of the affected soil and groundwater and the risk to the public health and the environment

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Determine the site-specific critical issues that drive the overall response action

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Develop the technical basis for a timely, cost-effective, and environmentally sound response plan

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Develop long-term, site-specific environmental liabilities management plan

Principles

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Driven by need to effectively manage the site and to protect the public health and the environment

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Evaluate local media:  soil, surface water, groundwater, and air

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Identify at-risk receptors and likely exposure pathways

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Determine all chemicals of concern

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Focus on source definition and control

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Focus on dissolved plumes

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Develop sufficient data to manage all site issues

 

Design, Construction, and Operation

The critical issues are:

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Health, safety, and quality take priority

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Use standard sized pumps,  meters, valves, controls, instruments, etc.

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 Allow for "easy" changes and modifications in response to progress results

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 Field fit most of mechanical and electrical

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 Realistic cost and schedule

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 Commit the necessary resources

 

Technology Selection and Sequence

The major factors are:

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Properties of the chemicals present in the soils and groundwater

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Status of potential pathways and receptors

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Site facilities, utilities, and support systems

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Project specific remediation criteria

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Cost and schedule considerations

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Progress monitoring and response

 

Remediation Technology Sequencing
(This table illustrates technology sequencing based on remedial effectiveness (cost and progress))

Technology

*Application range (ppb of VOCs in soils or groundwater)

100,000

10,000-100,000

1,000-10,000

500-1,000

<500

Excavation/Disposal/Treatment

X

 

 

 

 

In-Situ Thermal Desorption

X

 

 

 

 

Biopile Treatment

X

 

 

 

 

Soil Vapor Extraction/Thermal Oxidation

X

X

 

 

 

Pump and Treat

X

X

 

 

 

Chemical Oxidation

 

X

 

 

 

Air Sparging

 

X

 

 

 

Ex-Situ Groundwater Bioremediation

 

X

X

 

 

Bioventing

 

 

X

 

 

In-Situ Groundwater Bioremediation

 

 

X

X

 

Granular Activated Carbon

 

 

 

 

X

Monitored Natural Attenuation

 

 

 

 

X

* Approximate ranges based on cost and progress. 

Technology selection and sequence tends to be site-specific, depending on hydrogeology, receptors, chemicals present, etc.

 

Progress Measurement and Control

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Define the site-specific progress parameters

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Focused database management and reporting

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Regular reviews of progress trends

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Test progress trends with field tests

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Performance based measurement systems

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Flexible analytical and QA/QC

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Covers all media and matrices

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Analytical database drives process

 

 Program Controlled Analytical Capability

 

 Typical examples of progress curves are: 

 

 

 

 

 

 

 Physical Behavior of LNAPL Constituents
An understanding of the physical behavior of organic chemicals is critical to the design and operation of the remediation sequence. 

 

Physical Behavior of DNAPL Constituents

 

Free Product Removal

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Continuous belt separation

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Spiral pump at the interface

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Smart pumps

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Deep wells with deep sumps

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Solvent flushing

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Surfactant Enhanced Aquifer Remediation (SEAR)

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Two-phase extraction (vapor and liquid extracted together)

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Bioslurping - a type of TPE that maximizes LNAPL removal and bioventing

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Dual-phase extraction (gas and liquid extracted separately)

 

 

Dual Phase Extraction (DPE)
Install dual phase (vapor and water) extraction wells on most projects to expedite sequencing and response to progress data. 


 

 

Relative Oxidizing Power of Chemical Oxidants

Note:  The chemicals of concern, residual oxygen demand, and site-specific physical conditions determine the best chemical oxidant. 

Reactive Species

 

Relative Oxidizing Power (CI2-1.0)

Fluorine

 

2.23

Hydroxyl Radical (Fenton's)

 

2.06

Sulfate Radical

 

1.91

Ozone

 

1.77

Persulfate Anion

 

1.72

Hydrogen Peroxide

 

1.31

Permanganate

 

1.24

Chlorine Dioxide

 

1.15

Chlorine

 

1.00

Bromine

 

0.80

Iodine

 

0.54

 

Intrinsic Biodegradation Processes
This schematic illustrates the relative performance range for the major biodegradation processes. 

 

Biocatalysis/Biodegradation Database
Biological conditions exist that will biodegrade most combinations of organic chemicals at most sites.  Need to design systems to optimize the process.

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131 Pathways

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831 Reactions

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785 Compounds

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530 Enzymes

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326 Microorganisms

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110 Biotransformation rules

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50 Organic functional groups

Predict microbial catabolic reactions

Biochemical periodic table

 

Ways to Deliver Oxygen to the Subsurface
The oxygen needs to be available to the subsurface biological community to satisfy the stimulated oxygen demand. 

 Method

O2

 Demand

 

 

Hydrogen peroxide injection

High

Air/oxygen sparging, pulsed

Medium

Diffusive oxygen emitters

Medium

Eductors, supersaturate,  P & T

Medium

In-well oxygenation (course/fine bubble, gas aphrons)

Medium

Electrolysis (H2O ? H2 and O)

Low

Solid forms (oxygen/magnesium)

Low

 

In-Situ Bioremediation

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Most Volatile Organic Compounds (VOCs) are biodegradable

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Optimize electron acceptors/donors, nutrients, pH and other factors

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Several approaches:

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Direct injection of amendments to subsurface

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Extraction/reinjection of water with amendments

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Membrane diffusion of amendments into groundwater

 

In-Situ Bioremediation, Schematic System Layout 

 

Mobile Well Service Unit
Most in-situ bioremediation systems only require periodic treatment in terms of extraction, water treatment, and injection of nutrients and electron donors.  A single service unit can handle up to 8 sites within a 50-mile radius. 

 

Phytoremediation 

 

 

HC

Cl-HC

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Gradient control/evapotranspiration

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 Rhizosphere biodegradation

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Native species perform best

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 Low maintenance conditions

 

 

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Plant selection influenced by water balance

         Model transpiration rate, stand density

 

 

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 Irrigation required to establish stand

         Deep watering stimulates root growth

 

 

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Water/soil quality affects establishment

         Salt concentration, pH

 

 

 Note:    HC - hydrocarbon; organic chemical

             Cl-HC - chlorinated organic chemical

 

Natural Attenuation Processes 

 

HC

Cl-HC

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Destructive (mass reduction)

   

         Intrinsic biodegradation

         Abiotic chemical reactions

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Non-destructive (mass conservative)

   

         Adsorption to organic fraction

 -

 -

         Dispersion

         Advection

         Diffusion

        Volatization

        Dilution

 

Microbial Metabolism of Organic Matter 

Respiration Process

Electron Acceptor

Metabolic Products

Relative Potential Energy

 

 

 

 

Aerobic Respiration

O2

CO2, H2O

High

Denitrification

NO3-

CO2, N2

 

Iron reduction

Fe3+

CO2, Fe2+

 

Sulfate reduction

SO42-

CO2, H2S

 

Methanogenesis

CO2

CH4

Low

 

Suflita and Sewell (1991)

 

 

 

Transition to Natural Attenuation

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Active remediation end point

        Analytical basis

        Physical basis

        Chemical basis

        Modeling

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Cost/benefit analysis

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Human health and environmental risk assessment

        Attenuation action levels

        Concentration reduction factors

        Final compliance goals

 

Transition to Natural Attenuation

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Monitoring network adequate to track progress

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Expect some rebound : equilibration

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Evaluate rebound and overall database

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Periodically reevaluate risk to nearest receptors

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Allow time for natural attenuation to work

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Develop rebound response plan

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Everything is site-specific

 

Chlorinated Hydrocarbon Remediation

 

Extraction Well Progress

 

Monitoring Well Progress

 

 

Chlorinated Hydrocarbon Remediation, Intermittent System

 

Progress Curve, Mixed Chemical Site

 

 

Remediation Technology Sequencing 

Technology

*Relative Cost, $x103

Typical Effective Range, ppb VOCs

Typical Duration Months

 

Design

Construction

Monthly O&M

 

 

Excavation/Disposal/Treatment

10

40

2

>100,000

2-3

In-Situ Thermal Desorption

10

70

50

>100,000

3-5

Biopile Treatment

5

20

4

>100,000

3-6

Soil Vapor Extraction/Thermal Oxidation

10

50

12

100,000-10,000

6-12

Pump and Treat

10

40

10

100,000-10,000

12-24

Chemical Oxidation

5

40

7

100,000-10,000

3-6

Air Sparging

10

45

10

100,000-10,000

10-15

Ex-Situ Groundwater Bioremediation

10

40

12

100,000-1,000

12-24

Bioventing

5

30

4

10,000-1,000

18-36

In-Situ Groundwater Bioremediation

7

45

12

10,000-1,000

18-36

Granular Activated Carbon

3

20

12

<500

NA

Monitored Natural Attenuation

4

20

2

<500

5-15 yrs

*These costs are relative to each other for a specific site.  The costs are based on timely, cost-effective technology sequencing.  These costs are for a typical gas station site.  Actual site-specific costs may vary.

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This site was last updated on January 16, 2009