PROJECT DISCOVERY RESEARCH - Determing Cost of Excavation of Land Contaminated for the Conversion of...

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PDETERM

CONTAMINAT

1

COLE DES MINES DE DOUAI

EPARTEMENT GENIE CIVIL

ROJECT DISCOVERY RESEARCHINING COST OF EXCAVATION OF LANDD FOR THE CONVERSION OF A BROWN

Encadran

Responsa

DA SILVA, Juliane

DEROCHE, LucLEVACHER, Benoit

Année: 2011/2012

IELD

: T.VALEYRE

le: C.ALARY



2

INTRODUCTION

Brownfields are described as former industrial sites - factories and associated land, such aswarehouses or landfills, which are now abandoned or underutilized. Brownfields have the following

characteristics: they are often built or vacant sites contaminated (soil or water) by chemicals or otherpollutants (Ministry of Municipal Affairs and Housing Ontario, 2000). The strong growth urbanpopulation, coupled with the expansion of cities, have refocused these sites once on the outskirts of cities, to densely urbanized spots. Strong pressure on land and urban real estate has pushed to find newareas for urban development. Urban brownfields have a reserve of space but create a problem relatedto the rehabilitation of contaminated land.

Among the issues, assessing the impact of chemical contaminants emitted by past humanactivities is a major scientific question. Thus the realization of their history would be a pre-diagnosisof their toxic potential. Indeed, soils are receptacles, and potential reservoirs of contaminants to whichpeople can be exposed by different routes of contacts. If this toxicity was managed upstream through aconsideration of environmental constraints, clearance and profitable use of brownfield sites would notbe a "burden" for landowners. Indeed, the often high costs of post-decontamination represent a majorobstacle to their redevelopment.

Thus, the geostatistical interpolation of pollutant concentrations in soil, associated withspecific scenarios, cartographic modeling allow a risk of a site and can assist decision-makers toestablish an action plan to put implemented for the success of their projects and optimize costs.

Fig 1: Example of extension and densification of the urban fabric



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MATERIALS AND METHODS

Risk Modeling

Risk and risk assessment:

The health risk is the ratio, depending on environmental parameters, between exposure tosubstances referenced and their toxicity; which beyond a certain threshold characterizes a danger tohumans. Thus if the risk is> 1, there is dangerous toxicity, and vice versa.

Risk = ECD / VTR

The EDI (Acceptable Daily Exposure) refers to the amount of pollutant absorbed by the bodywithin a defined activity. It is calculated from the concentration of pollutants and based on weight of

the individual and the numbers of days of exposure to a carcinogenic substance not, or numbers of days of lifetime, to a carcinogen (Development -durable.gouv, 2011, U.S. EPA, Exposure AssessmentHH).

The VTR, Toxic Reference Value represents the amount of pollutant toxic to humans. It isdescribed as "with threshold" when a maximum level of safe exposure for humans has beenestablished as the principle of the critical dose, and as "with no threshold" when we extrapolate effectsbased concentrations absorbed.

These concepts have been defined by major international organizations responsible forpollution risk (ATSDR, INERIS, Health Canada) creating a consensus around these principlesquantification of absorption of toxic substances by man.

Modeling:

General Principle:

The combination of the intrinsic characteristics of a pollutant to the environmental parametersof the scenario can be modeled for each route of exposure ECD. Indeed, the general idea is to link theproperties of a pollutant from the soil (concentration, volatility...) and its effects on man and on whatterms it will be absorbed by the body. This develops a scenario describing the characteristics of subjects or (weight, quantity absorbed...) and activity (time, effort...).

The choice of scenario is of utmost importance because the substance properties are constantregardless of the choice of the population concerned. Therefore the factors Time / Attendance andabsorbed Quantity / Weight are essential for the accuracy of ECD (Zmirou D. et al. 2003).



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Fig. 1: Modélisation des DJE

Routes of Exposure:

These are the input vectors of substances in the body. They are many due to the fact that thebody is complex and permeable. Only direct exposure pathways, ie having no intermediary betweenman and the pollutant (ie contamination and accumulation of pollutants along the food chain) were

studied (D. et al Zmirou . 2003). It should be distinguished, because despite having the same originsand despite the fact that the effects of pollutants on the body are unchanged, these vectors of contamination have a clean transfer model.

Exposure by Ingestion

In any scenario, the risk of exposure by ingestion is the amount of soil that is absorbed into thebody. These values differ depending on the population concerned (U.S. EPA, Exposure FactorsHandbook).

Ingestion ECD

= ∗ ∗ ∗ ∗

with: , the daily exposure (mg / kg.jour);

C, the concentration at the exhibition in the ground (mg/m3);Qing, the daily amount ingested (mg / day);FE, the exposure frequency (days / year);

DE, duration of exposure (years);P, the body weight of the target (kg);

ECD

AcceptableDaily

Exposure

PollutantCharacteristics

Population

Identification

Activities



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and Tm, the time averaged (days)Tm = DE * 365 for threshold substances,Tm = 70 * 365 for non-threshold substances.

Inhalation Exposure:

Pollutants may dissolve in the water in the soil and end up in the air because of their volatilityand evaporation. Indeed the toxins are transferred from the solid phase to the aqueous phase via theKoc and then to the gas phase via Henry's law (US. EPA).

Inhalation of gases from a contaminated soil

Thus, the concentration of pollutant that can be inhaled from the soil, Ci is:

= × ×

± × × ± ×

with:

H: Henry's law constantKoc: partition coefficient organic carbon / waterCsoil: soil concentration mg/m3Qs: Soil Density: 2.65 kg/m3Ow: Volume of water content in soil: 0.15 DefaultOa: Volume of air in the soil: 0.28 DefaultJib: Proportion of carbon: 0.06 Default

Inhalation ECD

= ∗ ∗ ∗ ∗

with

Ci: concentration of pollutant in the air from soilQi: The amount of air inhaled per hour (for a child: the 0.5 × 30 × 60 = 0.9 m ^ 3, or 1.08 kg) []

ECD Inhalation Interior

Inhalation within the EDI can be calculated from the concentration of pollutants in outdoor airthrough a diffusion factor α. (D. Henryon, 2009).



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ECD or ECD Inh Inh α = int ext (FD Tillman Jr., JW Weaver, 2006)

Diffusion factor α (Johnson and Ettinger, 1991)

Main Target Organs

Each pollutant has own effects on the body. However, the image of their group by chemicalfamily (BTEX, PAHs, COHV, ...) various studies have shown that they could address the same organsas a priority and therefore it was possible to together, either by their composition, but by their behavior(Lemière B. et al., 2008) and therefore according to their main target organs.

Fig.2: Tableaux de Classement des polluants présent par organes cibleFoie Système Nerveux Système

Respiratoire

Reins Système

Immunologique

1,1,2,2-tetrachloroéthane

1,1,2,2-tetrachloroéthane

1,2-dichloroéthane Cadmium Arsenic

1,2-dibromoéthane 1,1dichloroéthylène

Arsenic Chloroforme Benzo[b]fluoranthène

Acénaphtène 1,2-dichloroéthane Cadmium Éthylbenzène Benzo[g,h,i]pérylène

Arsenic 1,2-

dichloroéthylène

Chrome Fluoranthène Benzo[k]fluoranthèn

eChloroforme 1,2-

dichloroéthylène-1Naphtalène Mercure Chrome

Chlorure de vinyle Arsenic Nickel Nickel Chrysène

Chrysène Benzène O-xylène Plomb Plomb

Cuivre Chloroforme Zinc Pyrène Zinc

Éthylbenzène Chrysène Dibromochlorométhane

Bromochlorométhane

Dibromochlorométhane

Fluorène Chlorure deméthylène

Dibromométhane Dibromochlorométhane

Dibromométhane

O-xylène Mercure Benzo(a)anthracène

Dibromométhane Benzo(a)anthracène

1,1,1- O-xylène Antimoine Benzo(a)anthracèn Dibenzo(ah)anthrac



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trichloroéthane e ène

1,1,2-trichloroéthane

Plomb Selenium Selenium

Bromochlorométhane

Toluène

Dibromochlorométhane Trichloroéthylène

Dibromométhane Tétrachloroéthylène

Dibenzo(ah)anthracène

1,1,1-trichloroéthane

Selenium 1,1,2-trichloroéthane

Dibromométhane

Benzo(a)anthracène

Système Gatrique Peau Sang Système Cardio-Vasculaire

Endocrinia

1,2-dichloroéthane Arsenic Arsenic Arsenic Bromodichlorométhane

Arsenic Benzo[a]pyrène Benzène Mercure Dibromométhane

Chlorure deméthylène

Cuivre Fluorène Plomb Selenium

Naphtalène O-xylène Naphtalène Dibromométhane

Zinc Dibromométhane O-xylène Benzo(a)anthracène

Dibromométhane Phénanthrène Zinc Selenium

Benzo(a)anthracène Benzo(a)anthracène Dibromométhane

Antimoine Dibenzo(ah)anthracène

Selenium Selenium



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Summation of the ECD

For a given chemical compound i, its ECDs (after P. Imray, A. Langly, 2001) are cumulative

and are listed by primary target organs j.Therefore there is for each pollutant and by target organ, an ECD as:

= ECDInh + ECDIngand' =/)'

These factors are combining to a single organ, regardless of the component, it helped to modeled riskorgans (E. Nerrière, D. Zmirou, 2001).

' = *)'

APPLICATION:

Study Area:

The application of this methodology was tested on an industrial wasteland: the Union sitelocated in the towns of Roubaix-Tourcoing-Wattrelos in northern France. This site has housed variousindustrial activities on an area of 80 hectares (brewery, textile, petrochemical, metallurgy, gas works,coal yard, yard, etc), as well as the workers' dwellings. This site became an urban industrial wasteland

in the wake of industrial decline that began in the '70s (website of the Union).

Former activities have generated localized contamination of several families of pollutants:trace metals (ETM), aliphatic hydrocarbons (HC), polycyclic aromatic hydrocarbons (PAHs), volatilehalogenated organic compounds (COHV), Polychlorinated biphenyls (PCB) and benzenes,Ethylebenzènes, Toluenes (BTEX).

The urban renewal project provides a very strong imbrication of habitat and economicalactivities. This is part of the sustainable development policy with remediation of land which aims atcreating the first eco-neighborhood of Lille.

Risk mapping will help to better define the areas where excavation of the soil before treatment

is not mandatory and thus validate the adequacy of the project for the built and the unbuiltenvironment in accordance with their health criteria.



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Fig.4:Localisation du site de l'Union

Sampling and Chimical

The diversity of soil composition and their heterogeneity (embankments) led to a samplingcampaign by augers and shovels of 452 samples, following a systematic sampling scheme based on theconstraints facing the field of mesh between 30 and 40 m and at depths between 1 m and 4 m.

Pollutant concentrations have been provided through testing according to standards applicablein France:

− NF ISO 22155 - HS / GC / MS for COHV (assay by gas chromatography;− EN 14039 for Hydrocarbons by GC (assay by gas chromatography in the range C10 to C40);

− XP X 33-012 for PCBs and PAHs (Dose by gas chromatography coupled with tandem mass

spectrometry (GC-MSMS));− NF EN ISO 11885 for Heavy Metals (Dosage of selected elements by optical emission

spectrometry with inductively coupled plasma frequency ICP-OES);

− NF ISO 16772 for Mercury (by atomic absorption spectrometry or cold vapor atomicfluorescence spectrometry cold vapor).

as well as for methods:− NF ISO 11464 (Sample preparation: sieving, storage, etc..);

− NF EN 12457-2 (leaching of waste with a granularity of less than 4 mm);

− NF ISO 11465 (water content of samples, by steaming).



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Creating the Scenario:

Generally, this step leads to determining or estimating for the type of people exposed:

The duration and frequency of exposure. They are estimations based on the habits and activities of the populations concerned. Only chronic exposure (continuous or recurrent exposure corresponding tothe significant fraction of life) are considered.

The physiological characteristics of subjects studied. This information differs depending on the typeof selected populations. They are the specific parameters that differentiate people, as weight, quantitiesintook and inhaled, etc.

Children were preferred in this study because they represent a sensitive population, andbecause of their development and behavior (ingestion of soil during the game, for example (A.Jacquet, 2007)), which makes the action of more harmful toxic substances (U.S. EPA, Human Health

Risk Assessment).A daycare center has been simulated with average attendance as: 8h/day, 5days/week,

47weeks/year. For two years that is:

No threshold: DE x EF = 235 x 2Tm 25550

With threshold: DE x EF = 235 x 2

Tm 730A quantity of soil ingestion of 100 mg / d (A. Jacquet, 2007)And a quantity of air inhaled (taken and adapted from: D. Bérubé et al, 1996)

Computing:

Calculation of risk coefficients for different routes of exposure

According to the compilation of the characteristics of the substances identified, and theparameterization of equations depending on the scenario, Excel spreadsheets © were used to calculatefor each pollutant and for each route of exposure the risk factors.

Ingestion Fig4.Risque

Ingestion Orale / àseuil

(mg/kg.j)

Orale / sansseuil

(mg/kg.j)^-1

Coef Risque

Hydrocarbures par CPG-

C10-C40 0,1 3462,603878

C10-C16 0,1 3462,603878

>C16-C22 2 173,1301939>C22-C30 2 173,1301939



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>30-C40 2 173,1301939

Composés Volatils

Dichlorométhane 0,05 6925,207756

Tétrachlorométhane 0,01 34626,03878

1,2-dichloroéthane 0,2 1731,301939

1,1,1-trichloroéthane 20 17,31301939

1,1,2-trichloroéthane 0,04 8656,509695

Cis-1,2-dichloroéthylène 0,017 20368,25811

Trans-1,2-dichloroéthylène 0,017 20368,25811

Chlorure de vinyle 0,003 115420,1293

1,1-dichloroéthylène 0,05 6925,207756

Bromochlorométhane 0,09 3847,337642

Bromodichloroéthane 0,02 17313,01939

Dibromochlorométhane 0,1 3462,603878Benzène 0,005 69252,07756

Toluène 0,8 432,8254848

Ethylbenzène 0,4 865,6509695

o - xylène 0,4 865,6509695

m+p - xylène 0,4 865,6509695

Hydrocarbures Aromatique Polycycliques(HAPs)

Naphtalène 0,6 577,1006464Acénaphtène 0,6 577,1006464

Fluorène 0,4 865,6509695

Phénanthrène 0,04 8656,509695

Anthracène 10 34,62603878

Fluoranthène 0,4 865,6509695

Pyrène 0,03 11542,01293

Chrysène 2,10E-03 164885,899

Benzo(b)fluoranthène 5,00E-03 6,93E+04

Benzo(k)fluoranthène 5,00E-03 6,93E+04

Benzo(a)pyrène 0,1369 2529,294286

Dibenzo(ah)anthracène 0,0005 692520,7756

Benzo(ghi)Pérylène 500 0,692520776

Indeno(1,2,3-c,d)pyrène 5,00E-03 69252,07756

Métaux par ICP/AES après minéralisation

Arsenic 0,0003 1,5 1154201,293

Cadmium 0,0005 ND 692520,7756

Chrome (VI) 0,003 0,42 115420,1293

Chrome (III) 1,5 ND 230,8402585Cuivre 0,14 ND 2473,288484



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Nickel 0,02 ND 17313,01939

Plomb 0,0035 98931,53937

Zinc 0,3 ND 1154,201293

Mercure par SFA

0,0001 ND 3462603,878

Fig6.Risque Inhalation Extérieur et Intérieur

Inhalation α VTR Inhalation COEF de RISQUES

à seuil(mg/m3)

sans seuil Extériereur

Intérieur

Hydrocarbures par CPG-

C10-C40 0,2 0 0C10-C16 0,2 0 0

Composés Volatils

1,2-dichloroéthane 0,01444

1,34E-06 4846003,533

69976,29101

1,1,1-trichloroéthane 8,21E-04

5,80E-11 6,31E+10 5,19E+07

1,1,2-trichloroéthane 8,21E-04

5,80E-11 6,31E+10 5,19E+07

Cis-1,2-dichloroéthylène 7,62E-04

3,20E-02 230,9726807

0,176093572

Trans-1,2-dichloroéthylène 7,62E-04

6,00E-02 126,5102692

0,096451429

Chlorure de vinyle 5,60E-04

0,1 77,4878649

0,043377707

Benzène 7,98E-04

0,06 121,8894342

0,097206824

Toluène 4,74E-04

3,85 0,41793501

0,000198101

Ethylbenzène 4,17E-04

2 3,324401854

0,001385943

o - xylène 8,90E-

04

0,7 8,8404753

81

0,00787

1559m+p - xylène 7,85E-

040,7 11,071217

10,00868

9245Hydrocarbures AromatiquePolycycliques (HAPs)

Naphtalène 6,62E-04

3,50E-03 142,9229339

0,094586398

Acénaphtène 5,02E-04

0,6 0,072771842

3,65024E-05

Fluorène 4,42E-04

0,4 0,040727555

1,80179E-05

Phénanthrène 1,10E-03 4079,074922 0



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Anthracène 1,10E-03 2,437528688

0

Fluoranthène 1,10E-03 0,259033155

0

Pyrène 3,51E-

04

1,10E-03 0,0002011

63

7,05879

E-08Chrysène (koc: moyenne) 1,64E-04

1,10E-03 0,004103685

6,73004E-07

Benzo(b)fluoranthène (moyennes) 2,91E-04

1,10E-03 5224,522604

1,518768721

Benzo(a)pyrène 1,10E-03 9,81003E-05

0

Benzo(ghi)Pérylène 1,10E-03 4,28765E-09

0

Indeno(1,2,3-c,d)pyrène 1,10E-03 5,72368E-05

0

PCB

PCB 28 a seuil:Sommedes DJE

4,91E-01 0,00E+00

PCB 52 1,51E+00 0,00E+00

PCB 101 1,04E-01 0,00E+00

PCB 118 5,00E-04 0,146831984

0,00E+00

PCB138 2,06E-02 0,00E+00

PCB 153 6,18E-02 0,00E+00

PCB 180 6,89E-02 0,00E+00

Mercure par SFA

3,81E-04

3,10E-05 250330,7433

95,42607933

Modeling and interpolation of concentrations of risk maps

One of the problems of mapping the risk of contaminated land lies in the interpolation of pointdata in order to model spatially throughout a site. That is to say, from the diverse and scattered pointsof which we know the coordinates, and the concentration of pollutants, we need to "estimate" valuesthat can be found anywhere on the site. To do this, geostatistics offers powerful tools for spatialmodeling from mathematical laws.



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where ,ℎ. is the semivariogram, or Act of dispersion, representing the zone of influence of the

pollutant. He characterizes the "Weight" of the component at any point depending on the distance hfrom a known point. (Matheron, 1962-63).

The choice was made the use of Kriging to interpolate the concentrations of differentpollutants and the Rasters to map the site using the software Arcgis 10 ©. This method, besidesproviding a precision much finer than the weighted average of inverse distance, can make a map of "inaccuracies" of uncertainty, represented by the map of standard deviation the error.

"Fig7: Card concentration

Using the calculator Raster Arcgis 10 © and risk coefficients previously calculated, theconcentrations were weighted, creating hazard maps by pollutant for each route of entry.To make their immediate reading possible, their scales of values have been changed in order to showthe areas at risk or not.

"Fig8



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Due to the summation of the ECD of various routes for the same organ, risk maps by bodieshave been established by overlaying the previous models, which, under the precautionary principle,could be superimposed with each other and create a map of general risk for the entire site.

Fig. 9 :



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Fig. 10: Carte Risque Système Nerveux



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DISCUSSION

According to the maps, the site of the Union seem presented areas with very high health risk.

However, given the risk maps Risk Liver and Nervous System, it appears an inconsistency

surévaluante the nervous system. The mere presence of PCBs, certainly very toxic compounds, can

not explain such a discrepancy. Indeed, their concentrations, although scattered throughout the site

are quite low (maximum: 0.5 mg / kg soil).

It seems that the interpolation method (Kriging Ordinary) is not the most relevant especially in the

interpolation of pollutant concentrations throughout the site. Indeed the disparity of data could lead

to errors in spatial modeling and thus estimated. Should be tested with other methods (Kriging

Glissant, the weighted average of inverse distance).

Furthermore, the modeling of risk factors for each pollutant ingestion was overvalued (bad

estimation of the frequency), which, combined with a very unfavorable scenario already have

aggravated this phenomenon.

The main limitations of this study lies in the inaccuracies related to various factors, and the non-

consensus on the calculation of Henry's constant and the diffusion coefficient α (J. Provoost et al.

2010). However, this does not undermine the general principle used and could, for mapping and

charting errors, help refine it.

So it would be interesting to study the predominance of organs or under certain conditions, because

there are few sets of values in the target organ sensitivity to toxic substances. That is to say,

whether, for example, in the case of inhalation of chloroform, the liver is more sensitive than he

nervous system, or conversely that pollutant as they are categorized both as a primary target organ?

If so, they are more serious effects on health in one case or the other? In other words, what is the

"weight" of the body factor in the case of poisoning with chemicals? This would refine this study by

weighting the risk maps of each body and have a finer edge of the area at risk on the entire site



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BIBLIOGRAPHY:

1. A.Jacquet (2007). Thesis: Amount of soil ingested recommended for a child: A choice tooconservative?

2. ATSDR - Glossary. Agency for Toxic Substances and Disease Registry, Atlanta, GA: U.S.Department of Health and Human Services, Public Health Services.(Http://www.atsdr.cdc.gov/glossary.html).

3. B. Lemière et al. - Guide on the behavior of pollutants in soil and ground-Document BRGM-New2008 Edition

4. D. Bérubé et al. (1996). Therapeutic modalities of asthma. Montreal: Publications, Department of Teaching Hospital Sainte-Justine (unpublished paper, presented as part of training for first responders

Line)

5. D. HENRYON (2009). Thesis: Methodological approach for a sustainable redevelopment of brownfields, no. Instructions: 40 125; University of Science and Technology of Lille Graduate SchoolSESAM 1-p 311

6. D. Zmirou et al. (2003). Waste and Soils, In: Environment and Public Health-Fundamentals andPractices, pp. 419-436. Edisem / Tec & Doc, Acton / Paris

7. E. Nerrière, D. Zmirou (2001). Assessment of health risk binds to air emissions from incineratorssubject to new limits of the European Union, University Institute of Hygiene and Public Health -INSERM Unit 420 - Faculty of Medicine. PP12-13

8. F. D. Tillman Jr., J. W. Weaver (2006). Uncertainty from synergistic effects of multiple parametersin the Johnson and Ettinger (1991) vapor intrusion model, Atmospheric Environment 40 (2006) 4098-4112. p 4101

9. G. Matheron (1962-1963). Treaty of geostatistical-Editions Technip, France.

10. J. Provoost et al. (2010). Vapour intrusion from the vadose zone seven Compared algorithms; J

Soils Sediments (2010) 10:473-483, DOI 10.1007/s11368-009-0127-4.

11. The Union - http://www.lunion.org/- April 2012

12. Mr. Bisson et al (2009) - Update on the Toxicological Reference Values (TRV) - March 2009,Study Report 17/03/2009; Reference: INERIS-DRC-08-94380-11776C (www.ineris.fr )

13. P. Imray, A. Langly (2001) - Health-based Soil Investigation Levels, Paragon Printers, 13-15Wiluna Street, Fyshwick ACT 2609, p 6

14. P.C. Johnson., R.A. Ettinger (1991). Heuristic Model for Predicting the intrusion rate of



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contaminant Vapors Into buildings. Environmental Science and Technology 25 (8) ,1445-1452.

15. Health Canada. Concentrations / Daily Intakes and concentrations / doses Tumorigenic PrioritySubstances calculated based on health criteria (www.hc-sc.gc.ca/francais/)

16. U.S. EPA (IRIS) - Reference Dose for Chronic Inhalation Exposure (RfC). U.S. EnvironmentalProtection Agency - Integrated Risk Information System. (Http://www.epa.gov/ngispgm3/iris/)

17. U.S. EPA (IRIS) - Reference Dose for Chronic Oral Exposure (RfD). U.S. EnvironmentalProtection Agency - Integrated Risk Information System. (Http://www.epa.gov/ngispgm3/iris/)

18. U.S. EPA (IRIS) - EPA On-line Tools for Site Assessment Calculation Screening-LevelImplementation of the Vapor Intrusion Johnson and Ettinger Modelwith Two variable / uncertainparameters (source depth, moisture content); Forward Calculation of Indoor Air Concentration. (Http:

/ / www.epa.gov/athens/learn2model/part-two/onsite/JnE_lite_forward.html). March 2012.

19. U.S. EPA (IRIS) - Exposure Assessment. U.S. Environmental Protection Agency, Integrated RiskInformation System. (Http://www.epa.gov/region8/r8risk/hh_exposure.html)

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