DISPERSION MODELLING OF DRILLING SITE NEAR DYBVAD CONTENTS APPENDICES. 1 Introduction Scope 2. 2 Limit values 2

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1 TOTAL E&P DENMARK B.V. DISPERSION MODELLING OF DRILLING SITE NEAR DYBVAD ADDRESS COWI A/S Parallelvej Kongens Lyngby Denmark TEL FAX WWW cowi.com CONTENTS 1 Introduction Scope 2 2 Limit values 2 3 Calculation input Emission sources Receptor grid Dispersion calculations 4 4 Results and conclusion 4 5 References 4 APPENDICES Appendix A Appendix B B.1 Normal operation PROJECT NO. A DOCUMENT NO. 2 VERSION 1.0 DATE OF ISSUE PREPARED Anna Juliane Clausen CHECKED Christian Nyander Jeppesen APPROVED Anna Juliane Clausen

2 2/16 DISPERSION MODELLING OF DRILLING SITE NEAR DYBVAD 1 Introduction COWI A/S have conducted dispersion calculations of NO 2 in OML-Multi 6.0 for TOTAL E&P Denmark B.V in relation to the drilling activities at a site near Dybvad. The results of the dispersion models are compared with the B-values. Address: TOTAL E&P Denmark B.V. Ovnstrupvej Dybvad 1.1 Scope The dispersion model is set up in OML-Multi 6.0 and covers dispersion of NO 2 at a drilling site near Dybvad in the northern part of Jutland, where TOTAL E&P Denmark B.V. is performing drilling activities for extraction of shale gas. Two generators are used for normal operation during the drilling phase for providing energy for the drilling equipment. There is 100% redundancy on site for power generation hence why more generators are available. TOTAL E&P Denmark B.V. has provided all input data. This report documents the emissions modelling based on: Two generators in operation with measured data. 2 Limit values Air pollution from industries are regulated according to the 'Luftvejledning' No The guidance document defines B-values for NO x. Table 1 shows the limit value of NO₂. Table 1: Limit values for diesel fired energy plants. B-value [mg/nm³] NO 2 0,125 3 Calculation input The following chapter describes the input data for the OML-model. 3.1 Emission sources The diesel generators are located adjacent to each other, and thus the same coordinates and origo applies for both generators. The generators are placed on a drilling platform raised above the ground level. The platform is approximately 2 meters high. From this level and to the point of

3 DISPERSION MODELLING OF DRILLING SITE NEAR DYBVAD 3/16 emission the height is approximately 4 m. Thus, the point of emission is placed 6 meters above ground level. In the model the stack height is thus set at 6 meters above ground level, though this will not be visible during a physical inspection at the site. The inner diameter is 0,39 m and the outer diameter is 0,4 m for both stacks. Table 2 shows the input parameters for the two generators. Table 2: Input data for the two emission sources Source Emission source ID X-coordinate [UTM] Y-coordinate [UTM] Stack height 1 [m] Inner diameter [m] Outer diameter [m] 1 Generator ,39 0,4 2 Generator ,39 0,4 The modelling and the related input data are further described in the sections below Normal operation 2 generators B-values have been calculated based on measured data. The water content in the exhaust is calculated based on stoichiometry and is 5,6 mole% with a measured oxygen content at 11,6 mole%, see appendix A for calculations. OML calculations have been carried out for two generators in operation. The two generators have different exhaust temperature and emission concentration, but the mass flow is similar. The input data are based on emission measurements conducted on the two generators. The mass flow is based on the load and manufacture data. Table lists the input data. Table 3: Input data (Data is measured, except for the mass flow, which is correlated on measured load with manufacturer s data) Source Emission source ID Exhaust temperature [ C] Emission concentration [mg/s] Mass flow [m³/s] Mass flow speed [m/s] 1 Generator 2 375,3 27,5 2,5 20,9 2 Generator 4 388,9 46,94 2,5 20,9 3.2 Receptor grid The receptor grid is constructed as a circular grid with origo ( , ), similar to the position of the generator. The grid range from 50 m to 2500 m.

4 4/16 DISPERSION MODELLING OF DRILLING SITE NEAR DYBVAD Topographical heights are implemented in the model, if heights of minimum 2-3 m above ground level within a radius of 300 m from the emission source, are observed. However, no such topographical levels are present at the site and therefore all topographical heights are set at 0 m. 3.3 Dispersion calculations For the dispersion calculations, a 1-year meteorological data set for Kastrup is used. The dispersion calculations are performed in a receptor height of 1,5 m and with an aerodynamic roughness length of 0,1 m. The aerodynamic roughness length are for the area of Denmark set a value of 0,1 m for the country side, where the site is located. The type of the surface is set at 2, corresponding to a grass areas. The topographical incline is set to 0. No buildings of relevance are present within the modelled area. 4 Results and conclusion Dispersion modelling of NO 2 were conducted. The output from the models is included in appendix B for July and August and summarised in Table Table 4: Results of the OML-modelling for the different scenarios for July and August. Scenario B-value [µg/m 3 ] Maksima of monthly 99%- fractiles [µg/m 3 ] Direction [ ] Distance [m] Month [Number] Normal operation , Normal operation , The table above shows that the limit values are met. 5 References Miljøstyrelsen, 2001, Luftvejledningen No

5 DISPERSION MODELLING OF DRILLING SITE NEAR DYBVAD 5/16 Appendix A Calculation of the exhaust water content based on an oxygen content of 11,6 molepercentage. If the concentration of oxygen is 11.6 mole%, then X = (999 * )/(-0.5 * ) = 59.8

6 6/16 DISPERSION MODELLING OF DRILLING SITE NEAR DYBVAD Appendix B B.1 Normal operation Dato: 2015/07/19 OML-Multi PC-version /6.01 Side 1 Dato: 2015/07/20 OML-Multi PC-version /6.01 Side 1 Licens til COWI A/S, Parallelvej 2, 2800 Kongens Lyngby Meteorologiske spredningsberegninger er udført for følgende periode (lokal standard tid): Start af beregningen = kl. 1 Slut på beregningen (incl.) = kl. 24 Meteorologiske data er fra: Kastrup Koordinatsystem. Der er anvendt et x,y-koordinatsystem med x-akse mod øst (90 grader) og y-akse mod nord (0 grader). Enheden er meter. Systemet er fælles for receptorer og kilder. Origo kan fastlægges frit, fx. i skorstensfoden for den mest dominerende kilde eller som i UTM-systemet. Receptordata. Ruhedslængde, z0 = m Største terrænhældning = 0 grader Receptorerne er beliggende med 10 graders interval i 15 koncentriske cirkler med centrum x,y: , og radierne (m): Alle terrænhøjder = 0.0 m. Alle receptorhøjder = 1.5 m. Alle overflader er typenr. = 2. Dato: 2015/07/20 OML-Multi PC-version /6.01 Side 2 Forkortelser benyttet for kildeparametrene: Nr...: ID...: X...: Y...: Z...: HS...: T...: VOL...: DSO...: DSI...: HB...: Qi...: Internt kildenummer Tekst til identificering af kilde X-koordinat for kilde [m] Y-koordinat for kilde [m] Terrænkote for skorstensfod [m] Skorstenshøjde over terræn [m] Temperatur af røggas [Kelvin]/[Celsius] Volumenmængde af røggas [normal m3/sek] Ydre diameter af skorstenstop [m] Indre diameter af skorstenstop [m] Generel beregningsmæssig bygningshøjde [m] Emission af stof nr. 'i' [gram/sek] Punktkilder

7 DISPERSION MODELLING OF DRILLING SITE NEAR DYBVAD 7/16 Kildedata: NOx Stof 2 Stof 3 Nr ID X Y Z HS T(C) VOL DSI DSO HB Q1 Q2 Q3 1 GenII GenIV Tidsvariationer i emissionen fra punktkilder. Emissionerne fra de enkelte punktkilder er konstant. Afledte kildeparametre: Kilde nr. Vertikal røggashastighed Buoyancy flux (termisk løft) m/s (omtrentlig) m4/s Der er ingen retningsafhængige bygningsdata. Dato: 2015/07/20 OML-Multi PC-version /6.01 Side 3 Side til advarsler. Dato: 2015/07/20 OML-Multi PC-version /6.01 Side 4 NOx År: 76 måned: 1 (Bidrag fra alle kilder) Maksimum= i afstand 50 m og retning 100 grader.

8 8/16 DISPERSION MODELLING OF DRILLING SITE NEAR DYBVAD Dato: 2015/07/20 OML-Multi PC-version /6.01 Side 5 NOx År: 76 måned: 2 (Bidrag fra alle kilder) Maksimum= i afstand 100 m og retning 310 grader. Dato: 2015/07/20 OML-Multi PC-version /6.01 Side 6 NOx År: 76 måned: 3 (Bidrag fra alle kilder)

9 DISPERSION MODELLING OF DRILLING SITE NEAR DYBVAD 9/ Maksimum= i afstand 100 m og retning 50 grader. Dato: 2015/07/20 OML-Multi PC-version /6.01 Side 7 NOx År: 76 måned: 4 (Bidrag fra alle kilder) Maksimum= i afstand 50 m og retning 50 grader.

15 DISPERSION MODELLING OF DRILLING SITE NEAR DYBVAD 15/ Maksimum= i afstand 50 m og retning 190 grader. Dato: 2015/07/20 OML-Multi PC-version /6.01 Side 16 NOx Periode: (Bidrag fra alle kilder) Maksima af månedlige Maksimum= i afstand 50 m og retning 270 grader i måned 10.

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