1

2

Definition of NAPL
NAPLs (Non-Aqueous Phase Liquids)

http://oceanworld.tamu.edu/resources/environment-book/groundwaterremediation.html□ DNAPLs (Dense Non-Aqueous Phase Liquids) Denser than water and does not dissolve in water It is immiscible or does not mix easily in waterex.) PCE, TCE, cis-DCE, Carbon Tetrachloride,Chloroform etc….

□ LNAPLs (Light Non-Aqueous Phase Liquids) Partially soluble in water and less dense than water “floats” on top of water and does not mix with water
 forms a pool of LNAPL in subsurface on water tableex.) Benzene, Toluene, Ethylbenzene, Xylene etc….
3

4Case Study of Monitored Natural
Attenuation (MNA) in South Korea

5

B'Study Area
400300200

A
Study area

B

A'100Background
Monitoring Well

00100

200

300

400

500

600

700

800

6

B’

Textile Co.

STREAM

Contamination source

A’A

B

LegendPaint Co.

Monitoring well

scale

Soil sampling site

7

Study Area

8

Soil Core Sampling9

Site Characteristics• Geologic & Hydrogeologic data collection:
Lithology : old stream bed, alluvium on weathered
granitic gneissHydraulic conductivity and gradient: average 2.6 X10-4 ~ 6.3 X10-4 m/sec and 0.0008
Effective porosity : 0.3
Advective groundwater velocity : 21.9 to 53 m/yr
Retardation coefficient : 2.18
Shallow groundwater users along plume path : none
10

Site Characteristics (cont’d)Contaminants : TEX (Mainly Toluene,Ethylbenzene, Xylene)
Contaminated soil zone : about 1.5m below
the ground surface- The zone becomes deeper along the downgradient direction- Concentration of groundwater becomes lower
along the down-gradient11

Site Characteristics (cont’d) The zones with higher concentrations in June 99 :two zones- Around the very down-gradient area from the tanks in Hpaint company- At the water storage tank in J textile company

 Feature of the plume- Length : about 600m, Width : about 150m

 Microbe degrading toluene- Mainly Pseudomonas fluorescence, Burkholderia cepacia,Acinetobacter lwoffii
12

Groundwater Monitoring• Groundwater Sampling• 1999. 6 ∼ 2001. 9• 8 sampling, 248 sample• Analysis• On-site : DO, Temp, ORP, Fe2+, Conductivity• Lab : TEX, NO3-, SO42- , Alkalinity

13

Monitoring Results
Jun-99Apr-00

Sep-01

Average평균농도Con.

Backgr.
배경농도Con.

Average평균농도Con.

Backgr.
배경농도Con.

Average평균농도Con.

Backgr.
배경농도Con.

DO(mg/l)

0.37?.26

0.60

1.03?.02

2.68

1.35?.04

2.18

NO3--N(mg/l)

6.68?9.82

11.86

0.67?.80

3.17

1.78?3.35

15.13

SO42-(mg/l)

40.31?34.09

83.19

4.14?.61

33.68

11.50?07.27

118.77Fe2+(mg/l)

58.19?5.64

0.03

53.18?0.32

N.D

51.92?0.48

N.D

TEX(mg/l)

159.37?14.47

2.047

43.69?8.48

0.038

34.39?6.44

0.16

ORP(mV)-196.55?6.62

172.90-51.13?3.03

65.10-28.47?19.47

101.00

Alkalinity(mg/l)

210.71?6.76

67.26

183.48?9.17

81.88

143.08?50.25

45.75
14

1999. 06

2001. 09

2000. 0415

Change of TEX concentration- contaminant sources and average values
700.000

500.000
L01

400.000

L03
LM02
Aver
평균.

300.000
200.000
100.000

1g001

Aun-Ju

Ap

r-01

01
b-0Fe

ec-0

D

ct

-000O

g000

Aun-JuApr-00

00
b-9Fe

ec-9

Dct-999O

g9

Aun-990.000

JuTEX concentration(mg/L)

600.000

Date16

Evaluation of the Model Simulation• To predict behavior of a contaminant plume in groundwater and its fate- MODFLOW-RT3D model Input parameters for groundwater flow system
Characteristics
1 layer
DomainGridRiver Boundary Elev. : 47 - 45m
Conductance(m2/day) 600 - 500
Cont. Head BoundaryK(m/s)
Ss(1/m)Sy
Por.(total)
Por.(eff.)
Bulk Density(kg/m3)
Recharge(mm/year)

1×10-50.00030.24
0.30.21700

2 layer801m×479m
Column : 70, Row : 71

Up-gradient : 47.5 - 46.3m
Down-gradient : 42.2 - 42m
2.6×10-4 - 6.3×10-4
0.00010.26
0.33
0.31490110

3 layer

1×10-7
4×10-6
1×10-60.08
0.00041800
17 Kinetic-limited Degradation of BTEX using Multiple Electron Accepters in RT3D
Parameter

Distribution coefficientd(L/mg)
K

Background concentration(mg/L)

Dispersion coefficient(m)

Item
BTEX
OxygenNitrateFerrous Iron
SulfateMethaneBTEX
OxygenNitrateFerrous Iron
SulfateMethaneLongitudinal
Trans./Long.
Vert./Long.

2Diffusion (m/day)

Stoichiometric ratio

Hydrocarbon decay rate

2+Max value of Fe(mg/L)
Max value of Methane (mg/L)

OxygenNitrateFerrous Iron
SulfateMethaneaerobic process
denitrificationiron reduction
sulfate reduction
methanogenesis

1 layer-52 layer

3 layer-6

3.45×10-52×10-5
4×10-52×10-5
4×10-52×10
0
2.35
16.1580.06
92.53

2×10-52×10-54×10-52×10-54×10-52×10
0
2.35
16.158
0.06
92.53

-5
7×10-52×10-54×10-52×10-54×10-52×10
0
2.35
16.158
0.06
92.53

-10
1×10-101×10
αL = 0.804
T/L=0.09
V/L=0.009
03.14
4.9
21.8
4.7
0.78
0.3
0.24
0.002
0.25
0.003
191.16
1-10
1×10

T/L=0.049
V/L=0.0049

T/L=0.001
V/L=0.001

18

 Calibration results of groundwater flow system
Steady state flow(1999.06)

Measured point : 61
Normalized RMS : 6.428033%

Transient flow (1999. 09)

Measured point : 61
Normalized RMS : 7.107084%
19 Calibration of initial concentration (1999. 06)

Measured point : 54, Normalized RMS : 10.81037% 20

 Distribution of initial concentration (1999. 06)

Core of plume(350mg/L)

1999. 0621

 Distribution of the predicted TEX plume (in 5 years)

Core of plume(160mg/L)- Reduced concentration : 190mg/L(54.3%), - Distance from L3 :22126m

 Distribution of the predicted TEX plume (in 10 years)

Core of plume(100mg/L)- Reduced concentration : 250mg/L(71.4%), - Distance from L3 : 293m
23 Distribution of the predicted TEX plume (in 20 years)
Core of plume(26mg/L)- Reduced concentration : 324mg/L(93%), - Distance from L3 : 407m
24

How to Improve Understanding& Implementation of MNA• Control/treat/remove sources• Thoroughly monitor a plume and down-gradient areas• Include contingencies for other measures if MNA fails
to meet desired goals• Involve regulatory agencies early in process25How to Improve Understanding& Implementation of MNA• Communicate that MNA is a responsible, managed
remediation approach (not a walk away)• Present site-specific data and analysis that
demonstrate occurrence• Develop defensible conceptual model supporting MNA• Build defensible predictive models, where appropriate

26

27

Thesis for a Ph.D. degree

Impact of Seasonal variationsin Hydrological stresses and Spatial
variations in Geologic conditions
on the Multiple DNAPL plumes

28

Site description

13/61□ Study area
 W Industrial Complex (WIC) constructed in 1970
 About 0.70 km2
 One large company
Approximately 23 small company

 The most of ground surface is paved(only about 9%  unpaved)
 W stream and S stream
RAO

 Monitoring wells : 51 (2009. 08): 77 (2011. 08)
Study area
<W Industrial Complex>

29

Site description

14/61□ Study area
 Surrounded by the low relief hills

 Two source spots (KDPW-02, GW-19)
Yang et al., 2003
Yu et al., 2006
Baek and Lee, 2011

 Extensive soil
sampling (GW-19)
 Main source area: RAO

 Trichloroethene (TCE)
Carbon tetrachloride(CT)

<RAO>

30

Hydrogeological characteristics□ Average annual rainfall

15/61

 Wonju meteorological station : 4 km distance Average annual rainfall : 1,392 mm(2006-2010)
 RAO : high groundwater recharge potential
 WIC : relatively limited recharge potential(Water level fluctuation, groundwater quality,
contaminant concentrations level)□ Aquifer matrix

 Paved surface
 Unconsolidated soil layer Weathered rock Intact Jurassic biotite granite Depth to water table : approximately 8 ~ 13 m
 Monitoring wells : 5 ~ 29 m in soil layer

31Hydrogeological characteristics

16/61□ Groundwater table fluctuation

 Groundwater flow direction
RAO : from southwest to northeast
WIC : from west to east Main source area (RAO)  Woosan industrial complex (WIC)KDPW-02 : 5.12 m
KDPW-04 : 4.64 m
GW-01 : 3.89 m

MW-03 : 1.42 m
MW-04 : 1.05 m
32

Contamination history□ History
 RAO known as the main source area Various solvents for the asphalt and concrete test
 Used for 16 year (1981 ~1997)?

 Trichloroethene (TCE), Carbon tetrachloride (CT)
 Chloroform
 In 2004, the topmost of contaminated soils(about 960 m3) treated by the low-thermal desorption
method33

Seasonal variations of DNAPL□ Seasonal variations of the multiple chlorinated contaminants
 Main contaminants (August 2009 ~ August 2011)
Trichloroethene : 2,569 ~ 15,748 ug/l
Carbon tetrachloride : 259 ~ 1,226 ug/l
Chloroform : 304 ~ 1,345 ug/l
 Main source area (TCE : KDPW-02)
15,748 ug/l  6,842 ug/l  8,673 ug/l(August 2009)(August 2010) (August 2011)
 Irregularly fluctuation and quasi-steady state The effects of dechlorination processes
cis-DCE : 40 ~ 160 ug/lDissolved oxygen : 4.60 ~ 5.90 mg/l (KDPW-02)
 appear to be minimal or weak34

Seasonal variations of DNAPL□ Variations of TCE and CT contaminant plumes

35

Field application method□ Diffusion sampler & automatic level logger Diffusion sampler (September 2009 and November 2009)
A string, string hanger, and semi-permeable chamber
Deionized water Multi-level well (MLW)May 2010 ~ August 2010

 Automatic level loggers (one hour interval)

15 m
25 m 15 m

CTD-diver, VANESSEN
Level logger, SOLINSTHeight above sea level (m, a.s.l.)

25 m
35 m 50 m
35 m

No scale

50 m

Multi-level well36

Results and discussion□ Seasonal impact analysis

 Variations of C/C0 at source area
positive relationship with hydraulic head
increase Variations of C/C0 at non-source area
dilution with recharged water Free-phase DNAPLs or residual
DNAPLs existence
around water table<Variations in TCE contaminant (C/C0)>37

Summary and conclusions
 The distribution of the multiple chlorinated contaminant plumes in groundwater at
an industrial complex, WIC was examined using various site characterizations.
 Areal heterogeneities in surface conditions could play an important role ingroundwater recharge and distribution of multiple chlorinated contaminant plumes.
 Observed multiple chlorinated contaminants had a strong positive correlation withhydraulic head change(the possible presence of free-phase DNAPLs or residual DNAPLs phase) The multiple chlorinated contaminant concentrations responded strongly to seasonalrecharge and to fluctuations in water table levels.
 The seasonal variations of the mass discharges at source area are strongly correlated withhydraulic characteristics.
 The multiple chlorinated contaminant could be a long term problem.

38

Remediation option□ Remediation

39

40

 Nine Government Ministries and 14 Acts
- Hot spring: Ministry of the Interior- Liquor: Ministry of Strategic and Finance- GW in army base: Ministry of Defense and so on Two Main Management Government Ministries- Soil and groundwater department of MOE: Quality- Water resource policy department of MOLIT (Ministry ofLand, Infrastructure and Transport): Quantity41

 Groundwater Act

Chapter III Preservation and Management of Groundwater- Article 16 (Orders, etc. to Prevent Pollution of Groundwater)(1) A person who develops and utilizes groundwater after obtaining permission,approval, etc. or making a report pursuant to this Act or other Acts shall takenecessary measures, such as the installation of facilities for preventing pollutionof groundwater, as prescribed by Presidential Decree(2) Where the Minister of Environment or the head of a Si/Gun/Gu (City) deems it
particularly necessary to prevent the pollution of groundwater, he/she may ordera person who installs or manages facilities which pollute or are likely toremarkably pollute groundwater to take measures for preventing the pollution ofgroundwater, as prescribed by Presidential Decree.
42 Groundwater Act- Article 16-2 (Prevention, etc. of Pollution by Facilities Causing GW Pollution)(1) A person who installs or manages any of the following facilities, which pollute or
are likely to pollute groundwater remarkably, shall take measures for preventing
the pollution of groundwater, measure groundwater quality by installing agroundwater pollution observation well, and report the result of themeasurement thereof to the head of a Si/Gun/Gu, as prescribed by Presidential
Decree: 1…, 2….

(2) When the pollution of groundwater… is likely to occur in the course of theoperation of facilities….., the manager of facilities…. shall take proper measures
without delay and report the occurrence thereof to the head of Si/Gun/Gu. …..

43 Groundwater Act- Article 16-3 (Measures on Manager of Facilities Causing GW Pollution)(1) Where the quality of groundwater does not conform to standards….., the Ministerof Environment or the head of a Si/Gun/Gu shall order the manager offacilities…..to perform water purification works….and to take other measures….
(2) Where the manager….fails to comply with an order…., the Minster of Environmentor the head of….may order him/her to suspend the operation…..or to close,
dismantle or relocate such facilities. (3)….

(3) Where it is unclear who is the manager of facilities…., the head of a.…may
directly perform the relevant water purification works.

44 Groundwater Act- Article 16-4 (Approval of Plan for Purification of Polluted GW, etc.)(1) When the manager…purifies polluted groundwater…or has been ordered topurify…, he/she shall purify polluted groundwater in conformity with standards
for purification…, and prepare a plan for purification…and submit it to thehead…and obtain his/her approval. The same shall also apply to cases where themanager….intends to change important matters prescribed by Ordinance of theMOE among approved matters(2) Where the head of a Si/Gun/Gu approves a plan for purification of polluted
groundwater pursuant to paragraph (1), he/she shall specify the period ofperformance of purification works.

45 Groundwater Act- Article 18 (Measurement of Water Quality Pollution)- Article 20 (Water Quality Testing, etc.)

Chapter V GW Impact Investigation Agency- Article 29-2 (Registration of Groundwater Purification Business)46

 Enforcement Decree of the Groundwater Act- Article 25 (Measures to Prevent Pollution of Groundwater, etc.)(1) A person who is obligated to take necessary measures,….shall take measures toprevent the pollution of groundwater according to the following standards:
1. …shall install the upper protective hole and the protective wall beneath thesurface of the earth of facilities….2-4….
5. He/she shall implement other measures for preventing the pollution ofgroundwater determined by the Minister of Environment.

47 Enforcement Decree of the Groundwater Act- Article 26 (Orders to Prevent Pollution of Groundwater, etc.)(1) The Minister of…or the head of…may order any installer or manager of facilities…
to take the following measures to prevent the pollution of groundwater…:
1. Installation of a GW pollution observation well and the measurement of GW quality;
2. Assessment of the progress of the pollution of GW;
3. Installation of facilities for preventing the leakage of groundwater pollutants;
4. Purification of polluted GW;
5. Improvements in equipment and the operation of the relevant facilities;
6. Closure, removal or dismantlement of the relevant facilities;(2) Matters necessary for orders to take measures to prevent the pollution of GW underparagraph (1) shall be prescribed by the Ordinance of the Ministry of Environment.
48

 Enforcement Decree of the Groundwater Act- Article 26-2 (Prevention of Pollution of Facilities Causing GW Pollution, etc.)- Article 26-3 (Measures with respect to Managers of Facilities Causing GW Pollution.)- Article 26-4 (Approval of Plans for Purifying Polluted Groundwater, etc.)- Article 29 (Water Quality Testing, etc.)- Article 30 (Institutions Specialized in Water Quality Testing, etc.)- Article 31 (Items, etc. of Water Quality Testing)- Article 39-2 (Registration of GW Purification Business)

 Enforcement Regulations of the Groundwater Act- By Orders from Ministry of Land, Infrastructure and Transport- By Orders for groundwater quality from Ministry of Environment
49

Groundwater Quality Standards(the last amendment; 2010.2.16) (Unit: mg/L)

50

Public Groundwater Quality Standards for Drinking Water(The last amendment; 2011.12.30)

Items

MCL

Total 47 Items
Total Colony Counts

Total Coliforms

100CFU/mL

ND/100mL

Hazardous
Volatile Organic
Substance (13)

Microbial (5)Hazardous
Inorganic
Substance (11)Hazardous
Volatile Organic
Substance (13)(Unit: mg/L)

Items

MCL

Xylene0.5mg/L

1,1-Dichloroethylene

0.03mg/L

1,4-Dioxane

0.05mg/L

1,2-Dibromo-3-Chloropropan

0.003mg/L

Carbontetrachloride

0.002mg/L

Diazinon

0.02mg/L

Parathion0.06mg/L

Fenitrothion

0.04mg/L

Carbaryl

0.07mg/L

Fecal Coliforms

ND/100mL

Escherichia Coli.

ND/100mL

Yersinia enteritidica

Nd/2L

Pb; Lead

0.01mg/L

F; Fluoride

1.5mg/L

Hardness

1,000mg/L

As; Arsenic

0.01mg/L

Consumption of KMnO410mg/L

Se; Selenium

0.01mg/L

Odor (except disinfection)

ND

Hg; Mercury

0.001mg/L

Cu; Cooper

1mg/L

CN; Cyanide

0.01mg/L

Color

5eh

Cr; Chromium

0.05mg/L

Surfactants

0.5mg/L

NH3-H

0.5mg/LpH

4.5-9.5

NO3-N; Nitrate Nitrogen

10mg/LZn; Zinc3mg/L

Cd; Cadmium

0.005mg/L

Cl-; Chloride

250mg/L

B; Boron

1.0mg/L

Fe; Iron

0.3mg/L

Phenol

0.005mg/L

Mn; Manganese

0.3mg/L

Turbidity

1NTU

1.1-Trichloroethane

0.1mg/L

SO42-; Sulfate

250mg/L

Al; Aluminium

0.2mg/L

PCE

0.01mg/L

TCE

0.03mg/L

Dichloromethane

0.02mg/L

Benzene0.01mg/Toluene0.7mg/L

Ethyl Benzene

0.3mg/L

Hazardous
Volatile Organic
Substance (Mainly Pesticide)(4)

Materials That Are Offensive To theHuman Sensory System (14)

51

52

References A Study of Degradation in Petroleum HydrocarbonPolluted Site by Enhancing Natural Attenuation(III), NIER No. 2001-30-622, 2001
 Impact of Seasonal Variations in Hydrologicalstresses and Spatial variations in Geologic
conditions on the Multiple DNAPL plumes, Ph.D.
Thesis of Yang, J.H., 2011
 Groundwater Act, 2015

 Enforcement Decree of the Groundwater Act, 2014 And so on….
53

E-mail address: hyd009@korea.kr54