BIOCHLOR

A Screening Level Natural Attenuation Model and Database for Solvents

C.E. AzizC. J. NewellA.P. Smith

Groundwater Services, Inc.

J.R. GonzalesP.E. Haas

Air Force Center for Environmental Excellence

Y. SunT.P. Clement

Battelle Pacific Northwest National Laboratory

BIOCHLOR ModelBIOCHLOR Model

Domenico Solution for Groundwater TransportDomenico Solution for Groundwater Transport

Reductive Dechlorination/Sequential First Order RxnsReductive Dechlorination/

Sequential First Order Rxns

Why Use BIOCHLOR?Why Use BIOCHLOR?

Method for Estimating Plume Lengths

System to Organize Site Data

Tool to Help Understand Site Processes

Screening Tool for Applicability of NA

Supporting Line of Evidence for NA

Method for Estimating Plume Lengths

System to Organize Site Data

Tool to Help Understand Site Processes

Screening Tool for Applicability of NA

Supporting Line of Evidence for NA

BIOSCREEN vs. BIOCHLOR: SimilaritiesBIOSCREEN vs. BIOCHLOR: Similarities

Domenico Analytical Model

Microsoft Excel Platform

User-Friendly Interface

Based on Site Database

Free Over the Internet

Domenico Analytical Model

Microsoft Excel Platform

User-Friendly Interface

Based on Site Database

Free Over the Internet

BIOSCREEN vs. BIOCHLOR: DifferencesBIOSCREEN vs. BIOCHLOR: Differences

Petroleum Hydrocarbon Sites – BTEX

Biodegradation:

Petroleum Hydrocarbon Sites – BTEX

Biodegradation:

BIOSCREENBIOSCREEN BIOCHLORBIOCHLOR

Solvent Sites

More Complex Biodegradation:

Solvent Sites

More Complex Biodegradation:- 1st Order Decay or

- Electron Acceptor Limited

- 1st Order Decay or

- Electron Acceptor Limited

- Sequential Reactions

- Different Zones

- Sequential Reactions

- Different Zones

BIOCHLOR: Key ProcessesBIOCHLOR: Key Processes

Advection (1-D)

Dispersion (3-D)

Sorption

Biodegradation:

- Reductive dechlorination

- Sequential reactions (parents to daughters)

- Limited hydrolysis

Different biodegradation zones

Advection (1-D)

Dispersion (3-D)

Sorption

Biodegradation:

- Reductive dechlorination

- Sequential reactions (parents to daughters)

- Limited hydrolysis

Different biodegradation zones

BIOCHLOR ModelBIOCHLOR Model

Domenico Solution for Groundwater TransportDomenico Solution for Groundwater Transport

Reductive Dechlorination/Sequential First Order RxnsReductive Dechlorination/

Sequential First Order Rxns

Sequential ReactionsSequential Reactions

PCE TCE DCE VC ETHPCE TCE DCE VC ETH

11 22 33 44

Rate PCE = – 1 C PCERate PCE = – 1 C PCE

Rate TCE = 1 y 1 C PCE – 2 C TCE Rate TCE = 1 y 1 C PCE – 2 C TCE

Reactive Transport EquationsReactive Transport EquationsReactive Transport EquationsReactive Transport Equations

A-D Equation (1-D advection, 3-D dispersion)

etc. ...

Rate PCE =Rate PCE =d CPCEd CPCE

d td t= L ( CPCE ) - 1 CPCE = L ( CPCE ) - 1 CPCE

Rate TCE =Rate TCE =d CTCEd CTCE

d td t= L ( CPCE ) + 1 y 1 CPCE - 2 CTCE = L ( CPCE ) + 1 y 1 CPCE - 2 CTCE

Rate TCE =Rate TCE =d CTCEd CTCE

d td t= L ( CPCE ) + 2 y 2 CTCE - 3 CDCE = L ( CPCE ) + 2 y 2 CTCE - 3 CDCE

L ( C 1 ) = – vL ( C 1 ) = – vd C1d C1

d xd x+ Dx+ Dx

d 2C1d 2C1

d x 2d x 2+ Dy+ Dy

d 2C1d 2C1

d y 2d y 2+ Dz+ Dz

d 2C1d 2C1

d z 2d z 2

BIOCHLOR ModelBIOCHLOR Model

Domenico Solution for Groundwater TransportDomenico Solution for Groundwater Transport

Y. Sun / T.P. Clement Transformation

Y. Sun / T.P. Clement Transformation

Distance from SourceDistance from Source

1.0

0.8

0.6

0.4

0.2

0

TCE

DCE

VC

Results in BIOCHLORResults in BIOCHLOR

BIOCHLOR Model: Other FeaturesBIOCHLOR Model: Other Features

Two Reaction Zones for Mixed Sites

Zone 1:Zone 1:High Decay RatesHigh Decay Rates(Carbon Present)(Carbon Present)

Zone 2:Zone 2:Low Decay RatesLow Decay Rates(No Carbon)(No Carbon)

SourceSource PCE TCE DCE

VC

ETH

PCE TCE DCE

VC

ETH

PCE TCE DCE

VC

ETH

PCE TCE DCE

VC

ETH

Zone 1Zone 1 Zone 2Zone 2

BIOCHLOR Model: Other FeaturesBIOCHLOR Model: Other Features

Single Vertical Plane Source Single Vertical Plane Source

Superimposed Sources(Connor et al., 1995)

Superimposed Sources(Connor et al., 1995)

Source 1

Source 2

Source 3

Predicts Parent, Daughter Compound Concentrations

Predicts Parent, Daughter Compound Concentrations

BIOCHLOR Model: SummaryBIOCHLOR Model: Summary

Provides Analytical Solution to Transport Equations with Sequential Reactions

Provides Analytical Solution to Transport Equations with Sequential Reactions

Simulates Two Biodegradation Zonesfor Mixed Sites

Simulates Two Biodegradation Zonesfor Mixed Sites

Zone 1Zone 1 Zone 2Zone 2

BIOCHLOR Version 2.0BIOCHLOR Version 2.0

Rate Constant Decision Support System

Source Decay Option

Animation Feature

Rate Constant Decision Support System

Source Decay Option

Animation Feature

Version 1.0:

Available on CD OR Download free

Currently: www.gsi-net.com

Jan. 2000: www.epa.gov/ada/models.html ( CsMOS Web Page )

How To Get BIOCHLOR . . .How To Get BIOCHLOR . . .

Version 2.0:

Available: Fall 2000

BIOCHLORBIOCHLOR Demonstration DemonstrationBIOCHLORBIOCHLOR Demonstration Demonstration

Case Study: Cape Canaveral AS, Fire Training Area

Release: Solvents, degreasers, JP fuels (1965-1985)

Site HydrogeologySite Hydrogeology::

Avg. Depth to Groundwater Avg. Depth to Groundwater

Hydraulic Conductivity Hydraulic Conductivity

Hydraulic Gradient Hydraulic Gradient

Typical Groundwater Seepage Velocity

Typical Groundwater Seepage Velocity

1.8 x 10-2 cm/sec1.8 x 10-2 cm/sec

0.0012 ft/ft0.0012 ft/ft

112 ft/yr112 ft/yr

5 ft BGS5 ft BGS

BIOCHLOR Interface – Input Parameters

BIOCHLOR Output

Individual Chlorinated Solvent Output

Array Output