3402_Forsyth_HanesMillRoad_MSWLF_ClosedUnlinedGWCA_BiochlorModel_FID1387918_20200121

hdrinc.com
January 21, 2020
Ms. Jaclynne Drummond, Compliance Hydrogeologist
NC Department of Environmental Quality
Division of Waste Management, Solid Waste Section
1646 Mail Service Center
Raleigh, NC 27699-1646
Dear Ms. Drummond:
On behalf of City of Winston-Salem, HDR Engineering, Inc. of the Carolinas is submitting the
annual Monitored Natural Attenuation screening model (BIOCHLOR) results for the Fall 2018 and
Spring 2019 events, as required in Attachment 4, Part II. Item 12 of the Permit Approval to Operate,
Permit for Closure: Hanes Mill Road Landfill 3402-MSWLF-1997, dated July 25, 2017.
The modeling results indicate that the input parameters for the BIOCHLOR model are applicable
and that biodegradation of chlorinated organic compounds via monitored natural attenuation (MNA)
remains active at the site.
Please contact us with any questions or concerns regarding this report.
Sincerely,
HDR Engineering, Inc. of the Carolinas
Mark P. Filardi, PG
Associate, Senior Geologist
cc: Jan McHargue, City of Winston-Salem
file
Enclosure
440 S Church Street, Suite 1000, Charlotte, NC 28202-2075
704.338.6700
Michael D. Plummer
SAA Waste Section Manager

Attachment 1
BIOCHLOR Modeling Results for December 2018 Monitoring Period
Hanes Landfill Closed Unlined Cell
Assumption
The maximum chlorinated compound concentrations (PCE, TCE, DCE, and VC) from
the groundwater monitoring available from 2002 to 2018 were used because the actual
source concentrations are unknown.
Model Input Data
1. Advection: Seepage Velocity, hydraulic gradient, and effective porosity (presented in
figure below) are all based on site conditions at the landfill.
2. Dispersion Input Parameter: ax, ay/ax, and az/ax inputs are all based on the instruction
for the BIOCHLOR program
3. Adsorption: Default values from the BIOCHLOR program were applied. A soil bulk
density of 1.6 kg/L, foc of 1.8 x 10-1, and Koc values of 426 L/kg (PCE), 130 L/kg (TCE),
125 L/kg (DCE), 30 L/kg (VC), and 302 L/kg (ETH) were used within the model to
calculate a retardation factor of 2.87. This value was used throughout the rest of the
model.
4. Biotransformation: The biotransformation first orders Decay coefficients lamda (1/yr) for
PCE-TCE (0.45), TCE-DCE (0.55), DCE-VC (0.8), and VC-ETH (12) from Zone 1 were
obtained based on Table 2.2 of the BIOCHLOR Addendum Manual (March 2002); and
were adjusted by fitting 2018 field VOC data to the sequential 111 order decay modeling
VOC concentration curve.
5. General: Only the VOC data from 2002 to current period for the OW wells were available
and the source VOC concentrations unknown. The maximum groundwater VOC
concentrations from 2002 to 2018 were used as the source input and the modeling time is
therefore set for 17 years (from 2002 to 2018). The model width is 1000 ft (limited zone of
VOC detection based on historic data) and modeling length is 600 ft (maximum distance
from landfill to the down gradient stream).
6. Source Data: The source data entered into the model determine how the concentrations
in the source area change over time. The source thickness in the saturated zone is 50 ft.
For the source concentrations the maximum groundwater VOC concentrations from

2002 to 2019 were used. These are: PCE = 0.026 mg/L; TCE 0.19 mg/L; DCE = 0.39
mg/L; VC = 0.13 mg/L; and ETH = 0.028 mg/L. The maximum Decay Rate Constants ks
(1/yr) allowed by the model were used.
7. Field Data: The groundwater data collected in the field efforts from 2018 were used for
the PCE, TCE, DCE and VC concentrations for W-3 (20 ft from the source), PW-4 (30 ft
from the source), PW-10D (215 ft from the source), and OW-17D (450 ft from the
source). The field data values can be found in the BIOCHLOR Natural Attenuation
Decision Support System figure below in the seventh section (Field Data for
Comparison).

OW-3
Natural enua ion
Interpretation
Score
Screening
Inadequate evidence for anaerobic biodegradation* of chlorinated organics
0 to 5
Protocol
Limited evidence for anaerobic biodegradation* of chlorinated organics
6 to 14
Score: 19
The following is taken from the usEPA protocol tusEPA, tsgsl.
Adequate evidence for anaerobic biodegradation* of chlorinated organics
15 to 20
The results of this scoring process have no regulatory
significance.
Scroll to End of Table
Strong evidence for anaerobic biodegradation* of chlorinated organics
>20
Concentration in *mduchvedechlorination Points
Analysis Most Contam. Zone Interpretation Yes No Awarded
Oxygen*
<0.5 mg/L
Tolerated, suppresses the reductive pathway at higher
Dp
O
3
concentrations
> 5mg/L
Not tolerated; however, VC may be oxidized aerobically
O
0
0
Nitrate'
<1 mg/L
At higher concentrations may compete with reductive
OO
O
2
pathway
Iron II*
>1 mg/L
Reductive pathway possible; VC may be oxidized under
0
0
3
Fe III-reducin conditions
Sulfate*
<20 mg/L
At higher concentrations may compete with reductive
O
O
2
pathway
Sulfide*
>1 mg/L
Reductive pathway possible
0
0
Methane*
>0.5 mg/L
Ultimate reductive daughter product, VC Accumulates
0
0
Oxidation
<50 millivolts (mV)
Reductive pathway possible
0
O
1
Reduction
Potential* (ORP)
<-100mV
Reductive pathway likely
0
0
PH'
5 < pH < 9
Optimal range for reductive pathway
0
0
TOC
>20 mg/L
Carbon and energy source; drives dechlorination; can be
0
0
natural or anthropogenic
Temperature*
>20°C
At T >20°C biochemical process is accelerated
0
0
0
Carbon Dioxide
>2x background
Ultimate oxidative daughter product
0
0
0
Alkalinity
>2x background
Results from interaction of carbon dioxide with aquifer
0
0
minerals
Chloride*
>2x background
Daughter product of organic chlorine
0
0
Hydrogen
>1 nM
Reductive pathway possible, VC may accumulate
0
0
Volatile Fatty Acids
>0.1 mg/L
Intermediates resulting from biodegradation of aromatic
0
0
0
compounds; carbon and energy source
BTEX*
>0.1 mg/L
Carbon and energy source; drives dechlorination
0
0
0
PCE*
Material released
0
0
0
TCE*
Daughter product of PCE aiO
O
2
DCE*
Daughter product of TCE.
If cis is greater than 80% of total DCE it is likely a daughter
OO
O
2
product of TCEa/; 1,1-DCE can be a them. reaction product of TCA
VC*
Daughter product of DCE'/
OO
O
2
1,1,1-
Material released
0
0
Trichloroethane*
DCA
Daughter product of TCA under reducing conditions
OO
0
2
Carbon
Material released
0
0
Tetrachloride
Chloroethane*
Daughter product of DCA or VC under reducing conditions
0
Q
0
Ethene/Ethane
>0.01 mg/L
Daughter product of VC/ethene
0
0
>0.1 mg/L
Daughter product of VC/ethene
0
0
Chloroform
Daughter product of Carbon Tetrachloride
0
0
0
Dichloromethane
Daughter product of Chloroform
0
0
0
* required analysis.
a/ Points awarded only if it can be shown that the compound is a daughter product SCORE Reset I
(i.e., not a constituent of the source NAPL).

r• �
Natural enua ion
Screening
Protocol
Interpretation
Score
Score: 13
Scroll to End of Table
Inadequate evidence for anaerobic biodegradation* of chlorinated organics
0 to 5
Limited evidence for anaerobic biodegradation* of chlorinated organics
6 to 14
The following is taken from the usEPA protocol tusEPA, tsgsl.
The results of this scoring process have no regulatory
significance.
Adequate evidence for anaerobic biodegradation* of chlorinated organics
15 to 20
Strong evidence for anaerobic biodegradation* of chlorinated organics
>20
Concentration in *mduchvedechlorination Points
Analysis Most Contam. Zone Interpretation Yes No Awarded
Oxygen*
<0.5 mg/L
Tolerated, suppresses the reductive pathway at higher
concentrations
Dp
O
3
> 5mg/L
Not tolerated; however, VC may be oxidized aerobically
O
0
0
Nitrate'
<1 mg/L
At higher concentrations may compete with reductive
pathway
O
0
0
Iron II*
>1 mg/L
Reductive pathway possible; VC may be oxidized under
Fe III-reducin conditions
O
0
0
Sulfate*
<20 mg/L
At higher concentrations may compete with reductive
pathway
O
O
2
Sulfide*
>1 mg/L
Reductive pathway possible
O
0
Methane*
>0.5 mg/L
Ultimate reductive daughter product, VC Accumulates
0
0
Oxidation
Reduction
<50 millivolts (mV)
Reductive pathway possible
0
0
Potential* (ORP)
<-100mV
Reductive pathway likely
0
0
0
PH'
5 < pH < 9
Optimal range for reductive pathway
0
O
0
TOC
>20 mg/L
Carbon and energy source; drives dechlorination; can be
natural or anthropogenic
0
0
Temperature*
>20°C
At T >20°C biochemical process is accelerated
0
0
0
Carbon Dioxide
>2x background
Ultimate oxidative daughter product
0
0
0
Alkalinity
>2x background
Results from interaction of carbon dioxide with aquifer
minerals
0
0
Chloride*
>2x background
Daughter product of organic chlorine
0
0
Hydrogen
>1 nM
Reductive pathway possible, VC may accumulate
0
0
Volatile Fatty Acids
>0.1 mg/L
Intermediates resulting from biodegradation of aromatic
compounds; carbon and energy source
0
0
0
BTEX*
>0.1 mg/L
Carbon and energy source; drives dechlorination
0
0
0
PCE*
Material released
0
O
0
TCE*
Daughter product of PCE ai
OO
O
2
DCE*
Daughter product of TCE.
If cis is greater than 80% of total DCE it is likely a daughter
product of TCEa/; 1,1-DCE can be a them. reaction product of TCA
OO
O
2
VC*
Daughter product of DCE'/
OO
O
2
1,1,1-
Trichloroethane*
Material released
0
0
DCA
Daughter product of TCA under reducing conditions
OO
O
2
Carbon
Tetrachloride
Material released
0
0
Chloroethane*
Daughter product of DCA or VC under reducing conditions
0
0
Ethene/Ethane
>0.01 mg/L
Daughter product of VC/ethene
0
0
>0.1 mg/L
Daughter product of VC/ethene
0
0
Chloroform
Daughter product of Carbon Tetrachloride
0
0
0
Dichloromethane
Daughter product of Chloroform
0
0
0
* required analysis.
a/ Points awarded only if it can be shown that the compound is a daughter product SCORE Reset
(i.e., not a constituent of the source NAPL).

OW-1 OD
Natural enua ion
Screening
Protocol
Interpretation
Score
Score: 14
Scroll to End of Table
Inadequate evidence for anaerobic biodegradation* of chlorinated organics
0 to 5
Limited evidence for anaerobic biodegradation* of chlorinated organics
6 to 14
The following is taken from the usEPA protocol tusEPA, tsgsl.
The results of this scoring process have no regulatory
significance.
Adequate evidence for anaerobic biodegradation* of chlorinated organics
15 to 20
Strong evidence for anaerobic biodegradation* of chlorinated organics
>20
Concentration in *mduchvedechlorination Points
Analysis Most Contam. Zone Interpretation Yes No Awarded
Oxygen*
<0.5 mg/L
Tolerated, suppresses the reductive pathway at higher
concentrations
Dp
0
3
> 5mg/L
Not tolerated; however, VC may be oxidized aerobically
0
0
0
Nitrate'
<1 mg/L
At higher concentrations may compete with reductive
pathway
0
0
0
Iron II*
>1 mg/L
Reductive pathway possible; VC may be oxidized under
Fe III-reducin conditions
0
0
0
Sulfate*
<20 mg/L
At higher concentrations may compete with reductive
pathway
0
O
0
Sulfide*
>1 mg/L
Reductive pathway possible
0
0
Methane*
>0.5 mg/L
Ultimate reductive daughter product, VC Accumulates
0
0
3
Oxidation
Reduction
<50 millivolts (mV)
Reductive pathway possible
0
0
Potential* (ORP)
<-100mV
Reductive pathway likely
0
0
PH'
5 < pH < 9
Optimal range for reductive pathway
Q
0
0
TOC
>20 mg/L
Carbon and energy source; drives dechlorination; can be
natural or anthropogenic
0
0
Temperature*
>20°C
At T >20°C biochemical process is accelerated
0
0
0
Carbon Dioxide
>2x background
Ultimate oxidative daughter product
0
0
0
Alkalinity
>2x background
Results from interaction of carbon dioxide with aquifer
minerals
0
0
Chloride*
>2x background
Daughter product of organic chlorine
0
0
Hydrogen
>1 nM
Reductive pathway possible, VC may accumulate
0
0
Volatile Fatty Acids
>0.1 mg/L
Intermediates resulting from biodegradation of aromatic
compounds; carbon and energy source
0
0
0
BTEX*
>0.1 mg/L
Carbon and energy source; drives dechlorination
0
0
0
PCE*
Material released
0
0
0
TCE*
Daughter product of PCE ai
OO
0
2
DCE*
Daughter product of TCE.
If cis is greater than 80% of total DCE it is likely a daughter
product of TCEa/; 1,1-DCE can be a them. reaction product of TCA
OO
0
2
VC*
Daughter product of DCE'/
OO
0
2
1,1,1-
Trichloroethane*
Material released
0
0
DCA
Daughter product of TCA under reducing conditions
OO
0
2
Carbon
Tetrachloride
Material released
0
0
Chloroethane*
Daughter product of DCA or VC under reducing conditions
0
Q
0
Ethene/Ethane
>0.01 mg/L
Daughter product of VC/ethene
0
0
>0.1 mg/L
Daughter product of VC/ethene
0
0
Chloroform
Daughter product of Carbon Tetrachloride
0
0
0
Dichloromethane
Daughter product of Chloroform
0
0
0
* required analysis.
a/ Points awarded only if it can be shown that the compound is a daughter product SCORE Reset I
(i.e., not a constituent of the source NAPL).

OW-17D
Natural enua ion
Screening
Protocol
Interpretation
Score
Score: 9
Scroll to End of Table
Inadequate evidence for anaerobic biodegradation* of chlorinated organics
0 to 5
Limited evidence for anaerobic biodegradation* of chlorinated organics
6 to 14
The following is taken from the usEPA protocol tusEPA, tsgsl.
The results of this scoring process have no regulatory
significance.
Adequate evidence for anaerobic biodegradation* of chlorinated organics
15 to 20
Strong evidence for anaerobic biodegradation* of chlorinated organics
>20
Concentration in *mduchvedechlorination Points
Analysis Most Contam. Zone Interpretation Yes No Awarded
Oxygen*
<0.5 mg/L
Tolerated, suppresses the reductive pathway at higher
concentrations
Dp
O
3
> 5mg/L
Not tolerated; however, VC may be oxidized aerobically
0
0
0
Nitrate'
<1 mg/L
At higher concentrations may compete with reductive
pathway
0
0
0
Iron II*
>1 mg/L
Reductive pathway possible; VC may be oxidized under
Fe III-reducin conditions
0
0
0
Sulfate*
<20 mg/L
At higher concentrations may compete with reductive
pathway
0
0
Sulfide*
>1 mg/L
Reductive pathway possible
0
0
Methane*
>0.5 mg/L
Ultimate reductive daughter product, VC Accumulates
0
0
Oxidation
Reduction
<50 millivolts (mV)
Reductive pathway possible
0
0
Potential* (ORP)
<-100mV
Reductive pathway likely
0
0
0
PH'
5 < pH < 9
Optimal range for reductive pathway
Q
0
0
TOC
>20 mg/L
Carbon and energy source; drives dechlorination; can be
natural or anthropogenic
0
0
Temperature*
>20°C
At T >20°C biochemical process is accelerated
0
0
0
Carbon Dioxide
>2x background
Ultimate oxidative daughter product
0
0
0
Alkalinity
>2x background
Results from interaction of carbon dioxide with aquifer
minerals
0
0
Chloride*
>2x background
Daughter product of organic chlorine
0
0
Hydrogen
>1 nM
Reductive pathway possible, VC may accumulate
0
0
Volatile Fatty Acids
>0.1 mg/L
Intermediates resulting from biodegradation of aromatic
compounds; carbon and energy source
0
0
0
BTEX*
>0.1 mg/L
Carbon and energy source; drives dechlorination
0
0
0
PCE*
Material released
0
0
0
TCE*
Daughter product of PCE aiO
O
2
DCE*
Daughter product of TCE.
If cis is greater than 80% of total DCE it is likely a daughter
product of TCEa/; 1,1-DCE can be a them. reaction product of TCA
OO
O
2
VC*
Daughter product of DCE'/
O
OO
0
1,1,1-
Trichloroethane*
Material released
0
0
DCA
Daughter product of TCA under reducing conditions
OO
0
2
Carbon
Tetrachloride
Material released
0
0
Chloroethane*
Daughter product of DCA or VC under reducing conditions
0
Q
0
Ethene/Ethane
>0.01 mg/L
Daughter product of VC/ethene
0
0
>0.1 mg/L
Daughter product of VC/ethene
0
0
Chloroform
Daughter product of Carbon Tetrachloride
0
0
0
Dichloromethane
Daughter product of Chloroform
0
0
0
* required analysis.
a/ Points awarded only if it can be shown that the compound is a daughter product SCORE Reset I
(i.e., not a constituent of the source NAPL).

BIOCHLOR Natural Attenuation Decision Support System
Version 2.2
Exce12000
TYPE OF CHLORINATED SOLVENT: Ethenes U
Ethanes O
1. ADVECTION
Seepage Velocity* Vs [
or
Hydraulic Conductivity K
Hydraulic Gradient i
Effective Porosity n 0.2 1 (-) 6. SOURCE DATA TYPE: Decaying
2. DISPERSION Source Options Single Planar
Alpha x* 60 (ft) Calc.
(Alpha y) / (Alpha x)* 0.1 (-) Source Thickness in Sat. Zone* F 50 (ft)
(Alpha z) / (Alpha x)* 1.E-99 (-) Y1
Width* (ft) 200
R ks*
or Conc. (mg/L)* C1 (1/yr)
Soil Bulk Density, rho 1.6 (kg/L) PCE .026 0
Fraction Organ icCarbon, foc 1.8E-3 (-) TCE .19 0
Partition Coefficient Koc y DCE .39 0
PCE 426 (L/kg) 7.13 (-) VC .13 0
TCE 130 (L/kg) 2.87 (-) ETH 0.028 0
DCE 125 (L/kg) 2.80 (-)
VC 30 (L/kg) 1.43 (-) 7. FIELD DATA FOR COMPARISON
3. ADSORPTION
Retardation Factor*
55.0 1 (ft/yr)
(cm/sec)
(ft/ft)
5. GENERAL
Simulation Time*
Modeled Area Width*
Modeled Area Length*
Zone 1 Length*
Zone 2 Length*
ETH 302 (L/kg) 5.35 (-) PCE Conc. (mg/L)
Common R (used in model)* = 2.87 TCE Conc. (mg/L)
4. BIOTRANS FORMATION -1st Order Decay Coefficient* DCE Conc. (mg/L)
Zone 1 _ 7v (1/yr) half-life (yrs) Yield VC Conc. (mg/L)
PCE � TCE 0.450 F 0.79 ETH Conc. (mg/L)
TCE � DCE 0.550 F 0.74 Distance from Source (ft)
Hanes Landfill
Closed Unlined
Run Name
(yr)
~ L
(ft)
j
(ft)
(ft)
0
(ft)
Zone 2=
Data Input Instructions:
115 1. Enter value directly .... or
T or 2. Calculate by filling in gray
0.02 cells. Press Enter, then
(To restore formulas, hit "Restore Formulas" button )
Variable* Data used directly in model.
Test if
Biotransformatio4 Natural Attenuation
is Occurrinq
;Vertical Plane Source: Determine Source Well
Location and Input Solvent Concentrations
i
View of Plume Looking Down
Observed Centerline Conc. at Monitoring Wells
11
11
11:
11:
--___--
1®
11
11
DCE 4 VC 0.800 F 0.64 Date Data Collected 2018
VC � ETH 12.000 F 0.45 8. CHOOSE TYPE OF OUTPUT TO SEE:
Zone 2 � k (1/yr) half-life (yrs)
PCE TCE 0.000 F
TCE � DCE 0.000 F HELP RUN CENTERLINE RUN ARRAY
DCE VC 0.000 F
VC � ETH 0.000 F
Help Restore RESET
SEE OUTPUT Paste

DISSOLVED CHLORINATED SOLVENT CONCENTRATIONS ALONG PLUME CENTERLINE (mg/L) at Z=0
Distance from Source (ft)
PCE
No Degradation
Biotransformation
0
60
120
180
240
300
360
420
480
540
600
0.026
0.025
0.024
0.022
0.019
0.016
0.012
0.009
0.006
0.004
0.002
0.0260
0.018
0.012
0.008
0.006
0.004
0.002
0.001
0.001
0.000
0.000
Monitorinq Well Locations
Field Data from Sitel 1 0.003 1 0.006 1 1
—No Degradation/Production —Sequential 1 st Order Decay
0.03
J 0.03
E 0.02 0 40
c
0.02
c�
0.01
c
0.01
� o
V 0.00 0 100 200 300
0 Field Data from Site
400 500
Distance From Source (ft.)
600 700
See TCE
See DCE
See VC
See ETH
i irne:
17.0 Years Return to
Prepare Animation To All To Array
Log ��Linear Input

DISSOLVED CHLORINATED SOLVENT CONCENTRATIONS ALONG PLUME CENTERLINE (mg/L) at Z=0
Distance from Source (ft)
TCE
No Degradation
Biotransformation
0
60
120
180
240
300
360
420
480
540
600
0.190
0.186
0.177
0.161
0.139
0.115
0.089
0.065
0.044
0.028
0.016
0.1900
0.128
0.086
0.056
0.037
0.023
0.015
0.009
0.005
0.003
0.002
Field Data from Sitel 0.002 1 0.005
—No Degradation/Production
0.20
J 0.18
0.16
E 0.14
= 0.12
0.10
a 0.08
0.06
v 0.04
c 0.02
V 0.00
0 100
Prepare Animation
Monitorinq Well Locations
0.008 1 0.008 1 1 1 1
—Sequential 1st Order Decay C Field Data from Site
See PCE
Q_^ Tru
See DCE
Rap yr
600 See ETH
200 300 400 500 600 700
Distance From Source (ft.)
i irne:
17.0 Years Return to
Input To All To Array
Log ��Linear

DISSOLVED CHLORINATED SOLVENT CONCENTRATIONS ALONG PLUME CENTERLINE (mg/L) at Z=0
Distance from Source (ft)
DCE
No Degradation
Biotransformation
0
60
120
180
240
300
360
420
480
540
600
0.390
0.382
0.364
0.331
0.286
0.235
0.182
0.133
0.091
0.057
0.034
0.3900
0.250
0.159
0.100
0.062
0.039
0.023
0.014
0.008
0.004
0.002
Monitorinq Well Locations
Field Data from Sitel 0.180 1 0.015 1 0.016 1 0.013 1
—No Degradation/Production —Sequential 1 st Order Decay
0.45
J 0.40
0.35
0.30 40
C 0.25
0.20 0
0.15
d 0.10
r_ 0.05
V 0.00 0 0
0 100 200 300
400
0 Field Data from Site
Distance From Source (ft.)
500
600
600
700
See TCE
See DCE
See VC
See ETH
i irne:
17.0 Years Return to
Prepare Animation To All To Array
Log ��Linear Input

DISSOLVED CHLORINATED SOLVENT CONCENTRATIONS ALONG PLUME CENTERLINE (mg/L) at Z=0
Distance from Source (ft)
VC
No Degradation
Biotransformation
0
60
120
180
240
300
360
420
480
540
600
0.130
0.127
0.121
0.110
0.095
0.078
0.061
0.044
0.030
0.019
0.011
0.1300
0.016
0.007
0.005
0.003
0.002
0.001
0.001
0.000
0.000
0.000
Monitorinq Well Locations
Field Data from Sitel
0.097
1 0.001
1 0.001
1
1 1
1
1
1
1
1
1
—No Degradation/Production
—Sequential 1 st Order Decay 0 Field Data from Site
0.14
See PCE
J 0.12
0
0
See TCE
E 0.10
40
C 0.08
See DCE
0.06
60
0.04
0
See VC
d
0.02
C
600
See ETH
V 0.00
0 100
200 300 400 500 600 700
Distance From Source (ft.)
i irne:
17.0 Years Return to
Prepare Animation
To All
To Array
Log ��Linear Input

Attachment 2
BIOCHLOR Modeling Results for March 2019 Monitoring Period Hanes
Landfill Closed Unlined Cell
Assumption
The maximum chlorinated compound concentrations (PCE, TCE, DCE, and VC) from the
groundwater monitoring available from 2002 to 2019 were used because the actual source
concentrations are unknown.
Model Input Data
1. Advection: Seepage Velocity, hydraulic gradient, and effective porosity (presented in
figure below) are all based on site conditions at the landfill.
2. Dispersion Input Parameter: ax, ay/ax, and az/ax inputs are all based on the
instruction for the BIOCHLOR program
3. Adsorption: Default values from the BIOCHLOR program were applied. A soil bulk
density of 1.6 kg/L, foc of 1.8 x 10-1, and Koc values of 426 L/kg (PCE), 130 L/kg (TCE),
125 L/kg (DCE), 30 L/kg (VC), and 302 L/kg (ETH) were used within the model to
calculate a retardation factor of 2.87. This value was used throughout the rest of the
model.
4. Biotransformation: The biotransformation first orders Decay coefficients lamda (1/yr)
for PCE-TCE (0.45), TCE-DCE (0.55), DCE-VC (0.8), and VC-ETH (12) from Zone 1
were obtained based on Table 2.2 of the BIOCHLOR Addendum Manual (March 2002);
and were adjusted by fitting 2019 field VOC data to the sequential 1st order decay
modeling VOC concentration curve.
5. General: Only the VOC data from 2002 to current period for the OW wells were
available and the source VOC concentrations unknown. The maximum groundwater
VOC concentrations from 2002 to 2019 were used as the source input and the modeling
time is therefore set for 18 years (from 2002 to 2019). The model width is 1000 ft (limited
zone of VOC detection based on historic data) and modeling length is 600 ft (maximum
distance from landfill to the down gradient stream).
6. Source Data: The source data entered into the model determine how the concentrations
in the source area change over time. The source thickness in the saturated zone is 50 ft.
For the source concentrations the maximum groundwater VOC concentrations from

2002 to 2019 were used. These are: PCE = 0.026 mg/L; TCE 0.19 mg/L; DCE = 0.39
mg/L; VC = 0.13 mg/L; and ETH = 0.028 mg/L. The maximum Decay Rate Constants ks
(1/yr) allowed by the model were used.
7. Field Data: The groundwater data collected in the field efforts from 2019 were used for
the PCE, TCE, DCE and VC concentrations for W-3 (20 ft from the source), PW-4 (30 ft
from the source), PW-10D (215 ft from the source), and OW-17D (450 ft from the
source). The field data values can be found in the BIOCHLOR Natural Attenuation
Decision Support System figure below in the seventh section (Field Data for
Comparison).

Natural enua ion
Screening 11
Protocol
Interpretation
Score
Score: 18
Scroll fo End of Table
Inadequate evidence for anaerobic biodegradation* of chlorinated organics
0 to 5
Limited evidence for anaerobic biodegradation* of chlorinated organics
6 to 14
The following is taken from the USEPA protocol (usEPA, tssal.
The results of this scoring process have no regulatory
significance.
Adequate evidence for anaerobic biodegradation* of chlorinated organics
15 to 20
Strong evidence for anaerobic biodegradation* of chlorinated organics
>20
Concentration in reductivedechlorinaaon Points
Analysis Most Contam. Zone Interpretation Yes No Awarded
Oxygen*
<0.5 mg/L
Tolerated, suppresses the reductive pathway at higher
concentrations
0
3
> 5mg/L
Not tolerated; however, VC may be oxidized aerobically
0
O
0
Nitrate*
<1 mg/L
At higher concentrations may compete with reductive
pathway
0
2
Iron II*
>1 mg/L
Reductive pathway possible; VC may be oxidized under
Fe III-reducin conditions
0
3
Sulfate*
<20 mg/L
At higher concentrations may compete with reductive
pathway
0
2
Sulfide*
>1 mg/L
Reductive pathway possible
0
O
0
Methane*
>0.5 mg/L
Ultimate reductive daughter product, VC Accumulates
0
0
Oxidation
Reduction
<50 millivolts (mV)
Reductive pathway possible
0
O
0
Potential* (ORP)
<-100mV
Reductive pathway likely
0
0
pH*
5 < pH < 9
Optimal range for reductive pathway
0
0
TOC
>20 mg/L
Carbon and energy source; drives dechlorination; can be
natural or anthro o enic
0
O
0
Temperature*
>20°C
At T >20°C biochemical process is accelerated
0
O
0
Carbon Dioxide
>2x background
Ultimate oxidative daughter product
0
O
0
Alkalinity
>2x background
Results from interaction of carbon dioxide with aquifer
minerals
0
0
Chloride*
>2x background
Daughter product of organic chlorine
0
Q
0
Hydrogen
>1 nM
Reductive pathway possible, VC may accumulate
0
O
0
Volatile Fatty Acids
>0.1 mg/L
Intermediates resulting from biodegradation of aromatic
compounds; carbon and energy source
0
0
BTEX*
>0.1 mg/L
Carbon and energy source; drives dechlorination
0
0
PCE*
Material released
0
0
TCE*
Daughter product of PCE a
0
2
DCE*
Daughter product of TCE.
If cis is greater than 80% of total DCE it is likely a daughter
product of TCEaf; 1,1-DCE can be a Chem. reaction product of TCA
OQ
0
2
VC*
Daughter product of DCE'/
0
2
1,1,1-
Trichloroethane*
Material released
0
0
DCA
Daughter product of TCA under reducing conditions
0
0
2
Carbon
Tetrachloride
Material released
0
0
Chloroethane*
Daughter product of DCA or VC under reducing conditions
0
0
Ethene/Ethane
>0.01 mg/L
Daughter product of VC/ethene
0
0
>0.1 mg/L
Daughter product of VC/ethene
0
0
Chloroform
Daughter product of Carbon Tetrachloride
0
0
Dichloromethane
Daughter product of Chloroform
0
O
0
* required analysis.
a/ Points awarded only if it can be shown that the compound is a daughter product SCORE Reset
i
(i.e., not a constituent of the source NAPL).

Natural enua ion
Screening 11
Protocol
Interpretation
Score
Score: 15
Scroll fo End of Table
Inadequate evidence for anaerobic biodegradation* of chlorinated organics
0 to 5
Limited evidence for anaerobic biodegradation* of chlorinated organics
6 to 14
The following is taken from the usEPA protocol (USEPn, tssa>.
The results of this scoring process have no regulatory
sigolficance.
Adequate evidence for anaerobic biodegradation* of chlorinated organics
15 to 20
Strong evidence for anaerobic biodegradation* of chlorinated organics
>20
" reductive dechlorination
Concentration in Points
Analysis Most Contam. Zone Interpretation Yes No Awarded
Oxygen*
<0.5 mg/L
Tolerated, suppresses the reductive pathway at higher
concentrations
0
3
> 5mg/L
Not tolerated; however, VC may be oxidized aerobically
0
O
0
Nitrate*
<1 mg/L
At higher concentrations may compete with reductive
pathway
0
2
Iron II*
>1 mg/L
Reductive pathway possible; VC may be oxidized under
Fe III-reducin conditions
0
0
Sulfate*
<20 mg/L
At higher concentrations may compete with reductive
pathway
0
2
Sulfide*
>1 mg/L
Reductive pathway possible
0
O
0
Methane*
>0.5 mg/L
Ultimate reductive daughter product, VC Accumulates
0
0
Oxidation
Reduction
<50 millivolts (mV)
Reductive pathway possible
0
O
0
Potential* (ORP)
<-100mV
Reductive pathway likely
0
0
pH*
5 < pH < 9
Optimal range for reductive pathway
0
0
TOC
>20 mg/L
Carbon and energy source; drives dechlorination; can be
natural or anthro o enic
0
O
0
Temperature*
>20°C
At T >20°C biochemical process is accelerated
0
O
0
Carbon Dioxide
>2x background
Ultimate oxidative daughter product
0
O
0
Alkalinity
>2x background
Results from interaction of carbon dioxide with aquifer
minerals
0
0
Chloride*
>2x background
Daughter product of organic chlorine
0
Q
0
Hydrogen
>1 nM
Reductive pathway possible, VC may accumulate
0
O
0
Volatile Fatty Acids
>0.1 mg/L
Intermediates resulting from biodegradation of aromatic
compounds; carbon and energy source
0
0
BTEX*
>0.1 mg/L
Carbon and energy source; drives dechlorination
0
0
PCE*
Material released
(0)
0
0
TCE*
Daughter product of PCE ai
0
2
DCE*
Daughter product of TCE.
If cis is greater than 80% of total DCE it is likely a daughter
product of TCEa/; 1,1-DCE can be a Chem. reaction product of TCA
DQ
0
2
VC*
Daughter product of DCE'/
0
2
1,1,1-
Trichloroethane*
Material released
0
0
DCA
Daughter product of TCA under reducing conditions
0
0
2
Carbon
Tetrachloride
Material released
0
0
Chloroethane*
Daughter product of DCA or VC under reducing conditions
0
0
Ethene/Ethane
>0.01 mg/L
Daughter product of VC/ethene
0
0
>0.1 mg/L
Daughter product of VC/ethene
0
0
Chloroform
Daughter product of Carbon Tetrachloride
0
0
Dichloromethane
Daughter product of Chloroform
0
O
0
* required analysis.
a/ Points awarded only if it can be shown that the compound is a daughter product SCORE Reset
(i.e., not a constituent of the source NAPL).
i

Natural enua ion
Screening 11
Protocol
Interpretation
Score
Score: 18
Scroll fo End of Table
Inadequate evidence for anaerobic biodegradation* of chlorinated organics
0 to 5
Limited evidence for anaerobic biodegradation* of chlorinated organics
6 to 14
The following is taken from the usEPA protocol (USEPn, tssa>.
The results of this scoring process have no regulatory
sigolficance.
Adequate evidence for anaerobic biodegradation* of chlorinated organics
15 to 20
Strong evidence for anaerobic biodegradation* of chlorinated organics
>20
" reductive dechlorination
Concentration in Points
Analysis Most Contam. Zone Interpretation Yes No Awarded
Oxygen*
<0.5 mg/L
Tolerated, suppresses the reductive pathway at higher
concentrations
0
3
> 5mg/L
Not tolerated; however, VC may be oxidized aerobically
0
O
0
Nitrate*
<1 mg/L
At higher concentrations may compete with reductive
pathway
0
2
Iron II*
>1 mg/L
Reductive pathway possible; VC may be oxidized under
Fe III-reducin conditions
0
0
Sulfate*
<20 mg/L
At higher concentrations may compete with reductive
pathway
0
2
Sulfide*
>1 mg/L
Reductive pathway possible
0
O
0
Methane*
>0.5 mg/L
Ultimate reductive daughter product, VC Accumulates
0
0
3
Oxidation
Reduction
<50 millivolts (mV)
Reductive pathway possible
0
O
0
Potential* (ORP)
<-100mV
Reductive pathway likely
0
0
pH*
5 < pH < 9
Optimal range for reductive pathway
0
0
TOC
>20 mg/L
Carbon and energy source; drives dechlorination; can be
natural or anthro o enic
0
O
0
Temperature*
>20°C
At T >20°C biochemical process is accelerated
0
O
0
Carbon Dioxide
>2x background
Ultimate oxidative daughter product
0
O
0
Alkalinity
>2x background
Results from interaction of carbon dioxide with aquifer
minerals
0
0
Chloride*
>2x background
Daughter product of organic chlorine
0
Q
0
Hydrogen
>1 nM
Reductive pathway possible, VC may accumulate
0
O
0
Volatile Fatty Acids
>0.1 mg/L
Intermediates resulting from biodegradation of aromatic
compounds; carbon and energy source
0
0
BTEX*
>0.1 mg/L
Carbon and energy source; drives dechlorination
0
0
PCE*
Material released
(0)
0
0
TCE*
Daughter product of PCE ai
0
2
DCE*
Daughter product of TCE.
If cis is greater than 80% of total DCE it is likely a daughter
product of TCEa/; 1,1-DCE can be a Chem. reaction product of TCA
DQ
0
2
VC*
Daughter product of DCE'/
0
2
1,1,1-
Trichloroethane*
Material released
0
0
DCA
Daughter product of TCA under reducing conditions
0
0
2
Carbon
Tetrachloride
Material released
0
0
Chloroethane*
Daughter product of DCA or VC under reducing conditions
0
0
Ethene/Ethane
>0.01 mg/L
Daughter product of VC/ethene
0
0
>0.1 mg/L
Daughter product of VC/ethene
0
0
Chloroform
Daughter product of Carbon Tetrachloride
0
0
Dichloromethane
Daughter product of Chloroform
0
O
0
* required analysis.
a/ Points awarded only if it can be shown that the compound is a daughter product SCORE Reset
(i.e., not a constituent of the source NAPL).
i

Natural enua ion
Screening 11
Protocol
Interpretation
Score
Score: 8
Scroll fo End of Table
Inadequate evidence for anaerobic biodegradation* of chlorinated organics
0 to 5
Limited evidence for anaerobic biodegradation* of chlorinated organics
6 to 14
The following is taken from the USEPA protocol (usEPA, tssal.
The results of this scoring process have no regulatory
significance.
Adequate evidence for anaerobic biodegradation* of chlorinated organics
15 to 20
Strong evidence for anaerobic biodegradation* of chlorinated organics
>20
Concentration in reductivedechlorinaaon Points
Analysis Most Contam. Zone Interpretation Yes No Awarded
Oxygen*
<0.5 mg/L
Tolerated, suppresses the reductive pathway at higher
concentrations
0
0
> 5mg/L
Not tolerated; however, VC may be oxidized aerobically
0
O
0
Nitrate*
<1 mg/L
At higher concentrations may compete with reductive
pathway
0
2
Iron II*
>1 mg/L
Reductive pathway possible; VC may be oxidized under
Fe III-reducin conditions
0
0
Sulfate*
<20 mg/L
At higher concentrations may compete with reductive
pathway
0
0
Sulfide*
>1 mg/L
Reductive pathway possible
0
O
0
Methane*
>0.5 mg/L
Ultimate reductive daughter product, VC Accumulates
0
0
Oxidation
Reduction
<50 millivolts (mV)
Reductive pathway possible
0
O
0
Potential* (ORP)
<-100mV
Reductive pathway likely
0
0
pH*
5 < pH < 9
Optimal range for reductive pathway
0
0
TOC
>20 mg/L
Carbon and energy source; drives dechlorination; can be
natural or anthro o enic
0
O
0
Temperature*
>20°C
At T >20°C biochemical process is accelerated
0
O
0
Carbon Dioxide
>2x background
Ultimate oxidative daughter product
0
O
0
Alkalinity
>2x background
Results from interaction of carbon dioxide with aquifer
minerals
0
0
Chloride*
>2x background
Daughter product of organic chlorine
0
Q
0
Hydrogen
>1 nM
Reductive pathway possible, VC may accumulate
0
O
0
Volatile Fatty Acids
>0.1 mg/L
Intermediates resulting from biodegradation of aromatic
compounds; carbon and energy source
0
0
BTEX*
>0.1 mg/L
Carbon and energy source; drives dechlorination
0
0
PCE*
Material released
(0)
0
0
TCE*
Daughter product of PCE a
0
2
DCE*
Daughter product of TCE.
If cis is greater than 80% of total DCE it is likely a daughter
product of TCEaf; 1,1-DCE can be a Chem. reaction product of TCA
DQ
0
2
VC*
Daughter product of DCE'/
0
Q
0
1,1,1-
Trichloroethane*
Material released
0
0
DCA
Daughter product of TCA under reducing conditions
0
0
2
Carbon
Tetrachloride
Material released
0
0
Chloroethane*
Daughter product of DCA or VC under reducing conditions
0
0
Ethene/Ethane
>0.01 mg/L
Daughter product of VC/ethene
0
0
>0.1 mg/L
Daughter product of VC/ethene
0
0
Chloroform
Daughter product of Carbon Tetrachloride
0
0
Dichloromethane
Daughter product of Chloroform
0
O
0
* required analysis.
a/ Points awarded only if it can be shown that the compound is a daughter product SCORE Reset
i
(i.e., not a constituent of the source NAPL).

BIOCHLOR Natural Attenuation Decision Support System
Version 2.2
Exce12000
TYPE OF CHLORINATED SOLVENT: Ethenes U
Ethanes O
1. ADVECTION
Seepage Velocity* Vs 55.0 (ft/yr)
or T
Hydraulic Conductivity K
Hydraulic Gradient i
Effective Porosity n
2. DISPERSION
Alpha x* 60 (ft)
(Alpha y) / (Alpha x)* 1 0.1 1 (-)
(Alpha z) / (Alpha x)* 1.E-99 1 (-)
3. ADSORPTION
Retardation Factor*
or
Soil Bulk Density, rho
Fraction Organ icCarbon, foc
Partition Coefficient
PCE
TCE
DCE
VC
ETH
Common R
4. BIOTRANS FORMATION
Zone 1
PCE TCE
TCE DCE
DCE 4 VC
VC ETH
Zone 2 �
PCE TCE
TCE DCE
DCE -31� VC
VC -> ETH
(cm/sec)
(ft/ft)
5. GENERAL
Simulation Time*
Modeled Area Width*
Modeled Area Length*
Zone 1 Length*
Zone 2 Length*
Hanes Landfill
Closed Unlined
Run Name
(yr)
~ L
(ft)
j
(ft)
(ft)
0
(ft)
Zone 2=
0.2 (-) 6. SOURCE DATA TYPE: Continuous
Source Options I Single Planar
Calc.
Source Thickness in Sat. Zone* F 50 (ft)
Y1
Width* (ft) 200
R ks*
Conc. (mg/L)* C1 (1/yr)
1.6 (kg/L) PCE .026 0
1.8E-3 (-) TCE .19 0
Koc y DCE .39 0
426 (L/kg) 7.13 (-) VC .13 0
130 (L/kg) 2.87 (-) ETH 0.028 0
125 (L/kg) 2.80 (-)
30 (L/kg) 1.43 (-) 7. FIELD DATA FOR COMPARISON
302
(L/kg)
5.35
(-)
PCE Conc. (mg/L)
used in model)* =
2.87
TCE Conc. (mg/L)
-1st Order Decay Coefficient*
DCE Conc. (mg/L)
a, (1/yr)
half-life (yrs) Yield
IVC Conc. (mg/L)
0.450
F
0.79
ETH Conc. (mg/L)
0.550
F
0.74
Distance from Source (ft)
Data Input Instructions:
115 1. Enter value directly .... or
T or 2. Calculate by filling in gray
0.02 cells. Press Enter, then
(To restore formulas, hit "Restore Formulas" button )
Variable* Data used directly in model.
Test if
Biotransformatio4 Natural Attenuation
is Occurrinq
Vertical Plane Source: Determine Source Well
Location and Input Solvent Concentrations
i
View of Plume Looking Down
Observed Centerline Conc. at Monitoring Wells
11
11
11•
1®
11
11
0.800 F 0.64 Date Data Collected_j 2018
12.000 F 0.45 8. CHOOSE TYPE OF OUTPUT TO SEE:
k (1/yr) half-life (yrs)
0.000 F
0.000 F HELP RUN CENTERLINE RUN ARRAY
0.000 F
0.000 F
Help
Restore RESET
SEE OUTPUT
Paste

DISSOLVED CHLORINATED SOLVENT CONCENTRATIONS ALONG PLUME CENTERLINE (mg/L) at Z=0
Distance from Source (ft)
PCE
No Degradation
Biotransformation
0
60
120
180
240
300
360
420
480
540
600
0.026
0.026
0.024
0.022
0.020
0.016
0.013
0.010
0.007
0.005
0.003
0.0260
0.018
0.012
0.008
0.006
0.004
0.002
0.001
0.001
0.001
0.000
Monitoring Well Locations
20 30 215 450
Field Data from Site 1 0.002 0.010
—No Degradation/Production —Sequential 1st Order Decay
0.03
J 0.03
Im 0
E 0.02
40
c
0.02
c�
0.01 0
m
0.01
0 0
U 0.00
0 100 200 300
400
0 Field Data from Site
Distance From Source (ft.)
Time:
18.0 Years
Prepare Animation
Log Linear
•11
600
600
Return to
Input
700
To All
See PCE
See TCE
See ETH
To Array

DISSOLVED CHLORINATED SOLVENT CONCENTRATIONS ALONG PLUME CENTERLINE (mg/L) at Z=0
TCE
No Degradation
Biotransformation
Distance from Source (ft)
0
60
120
180
240
300
360
420
480
540
600
0.190
0.187
0.179
0.164
0.144
0.120
0.096
0.072
0.051
0.033
0.021
0.1900
0.128
0.086
0.057
0.037
0.024
0.015
0.009
0.006
0.003
0.002
20 30
Field Data from Site 0.003 0.005
-No Degradation/Production
0.20
J 0.18
im 0.16
E 0.14
c 0.12
0.10
0.08
c 0.06
v 0.04
0 0.02
V 0.00
0 100
Monitorina Well Locations
215 450
0.009
-Sequential 1st Order Decay
0 Field Data from Site
200 300 400 500 600 700
Distance From Source (ft.)
coo arm
See TCE
See DCE
See VC
Es- ETH
Time:
11 18.0 Years Return to
Prepare Animation To All To Array
Log Linear Input

DISSOLVED CHLORINATED SOLVENT CONCENTRATIONS ALONG PLUME CENTERLINE (mg/L) at Z=0
Distance from Source (ft)
DCE
No Degradation
Biotransformation
0
60
120
180
240
300
360
420
480
540
600
0.390
0.383
0.367
0.336
0.295
0.247
0.196
0.147
0.104
0.069
0.042
0.3900
0.250
0.159
0.100
0.063
0.039
0.024
0.014
0.008
0.005
0.003
20 30
Field Data from Site 0.170 0.014
—No Degradation/Production
0.45
J 0.40
0.35
E 0.30
p 0.25
0.20
0.15 °
v 0.10
0 0.05
V 0.00 °
0 100
Prepare Animation
Monitoring Well Locations (ft)
215 450
0.023
—Sequential 1st Order Decay ° Field Data from Site
See PCE
0 See TCE
40
See DCE
0
0 See VC
7° 600 See ETH
200 300 400 500 600 700
Distance From Source (ft.)
Time:
18.0 Years Return to
Input To All To Array
Log Linear

DISSOLVED CHLORINATED SOLVENT CONCENTRATIONS ALONG PLUME CENTERLINE (mg/L) at Z=0
VC
No Degradation
Biotransformation
Distance from Source (ft)
0
60
120
180
240
300
360
420
480
540
600
0.130
0.128
0.122
0.112
0.098
0.082
0.065
0.049
0.035
0.023
0.014
0.1300
0.016
0.007
0.005
0.003
0.002
0.001
0.001
0.000
0.000
0.000
20 30
Field Data from Site 0.076 0.001
—No Degradation/Production
0.14
J 0.12
E 0.10
0 0.08
a 0.06
L
0.04
0 0.02
0
U 0.00
0 100
Prepare Animation
Monitoring Well Locations (ft)
215 450
0.001
—Sequential 1st Order Decay
200 300
0 Field Data from Site
0
400 500
Distance From Source (ft.)
Time:
18.0 Years
Log Linear
600
600 700
SPP PCF
See TCE
See DCE
See VC
See ETH
Return to To All To Array
Input