The Palmottu Natural Analogue Proiect

Transcription

1 The Palmottu Natural Analogue Proiect Technical Report Diffemnce flow measumments at the Palmottu site in bomholes R387 and R388 Pekka Rouhiainen and Petri Heikkinen PRG-tec Oy May 1998

2 TABLE OF CONTENTS ABSTRACT INTRODUCTION PRINCIPLES OF OPERATION INTERPRETATION EQUIPMENT SPECIFICATIONS RESULTS Difference flow measurement Detailed flow and single point resistance logs Temperature logs REFERENCES APPENDICES

3 DIFFERENCE FLOW MEASUREMENTS AT THE PALMOTTU SITE IN BOREHOLES R387 AND R388 ABSTRACT The developed difference flow method is used to detemine hydraulic conductivity and hydraulic head in fi-actures or fi-actured zones. The flow sensor for flow along a borehole and a new type of flow guide are used for this measurement. Measurements were perfomed at the Palmottu investigation site in boreholes R387 and R388 in March Measurement was begun in borehole R387 in pumped condition using ten metre section length.. Measurements continued using a two metre section length, but only at the depths where flow had been shown to exist in the ten metre measurements. Borehole R388 was measured completely with two metre section length. In addition to this, a detailed flow log was perfomed with ten centimeter point intervals. The flow guide encloses an electrode for single point resistance measurement. It was also logged during the flow measurements with one centimeter point intervals. This report presents the principles of the difference flow method as well as the results of the measurements carried out. Keywords: groundwater, flow, measurement, bedrock, borehole

4 EROMITTAUKSET PALMOTUSSA KAIRANREI'ISSA R387 JA R388 Kehitetyllä eromittausmenetelmalla voidaan suhteellisen nopeasti mitata reiassa vyöhykkeiden vedenjohtavuus ja painekorkeus. Menetelmässä käytetään virtausmittarin pystyvirtausanturia ja uudentyyppistä virtausohjainta. Palmotun tutkimusalueella tehtiin virtausmittauksia eromittausmenetelmalla kairanrei'issa R387 ja R388. Mittaukset ajoittuivat maaliskuulle Mittaukset aloitettiin reiassa R387 kymmenen metrin mittausvzililla pumppauksen aikana. Mittauksia jatkettiin kahden metrin mittausvalilla, mutta vain syvyyksilla, joissa virtausta oli havaittu kymmenen metrin mittausvalilla. Reikä R388 mitattiin kokonaan kahden metrin mittausvalilla. Tämän lisäksi tehtiin yhksityiskohtainen virtausmittaus kymmenen senttimetrin pistevalein. Virtausohjaimessa on myös elektrodi yksipistemaadoitusvastusmittaukseen. Tämä mitattiin virtausmittausten yhteydessä sentin pistevalein. Raportissa on esitetty eromittauksen periaate sekä mittaustulokset.

5 PREFACE The Palmottu Natural Analogue Project is jointly funded by the European Commission, the Geological Survey of Finland (GTK), the Radiation and Nuclear Safety Authority in Finland (STUK), Empresa Nacional de Residuous Radioactivos S.A. (ENRESA)/Centro de Investicationes Energéticas, Medioambientales y Technológicas (Ciemat), Svensk Karnbranslehantering AB (SKB) and Bureau de Recherches Géologiques et Minikres (BRGM), and by other partners.

6 1 INTRODUCTION The TVO-Flowmeter is designed to measure small groundwater flows in bedrock, both across and along a borehole. Using a new type of flow guide, flow into the hole or out fkom the hole at a chosen depth interval can be measured directly, instead of measuring flow along the borehole. This method is called difference flow measurement because differences of flow along the borehole are measured. The method makes it possible to obtain the hydraulic conductivity of the bedrock and the hydraulic head in fi-actures. One of the advantages of the method is that it is faster than the conventional double packer injection test. The equipment can be used in boreholes with a diarneter of 56rnrn or larger and depth of less than 1000m. The equipment consists of a trailermounted winch and cable, a downhole probe and a PC computer. Measurements were begun at the Palmottu site in borehole R387 on March 18, 1998 and in borehole R388 on March 25. The measurements were in progress during the nights when possible, in automatic operation mode. The field work was finished on March 27.

7 2 PRINCIPLES OF OPERATION The TVO-Flowmeter using the difference flow method can be employed to measure groundwater flow into or out fiom a given borehole section. Measurements can be performed with or without pumping water fiom the hole. Hydraulic conductivity and hydraulic head in fiactures or fractured zones can be deduced from the results if certain assumptions are made. The new method is a development of the conventional measurement of flow along the borehole. However, it is not the flow along the hole, but the changes of flow with depth that are usehl when interpreting the results. Measurement of flow along a hole is problematic especially when the flow is strong because small changes in the flow may be concealed. This problem can be avoided if the changes of flow are measured directly. With the new flow guide, flow along the hole is directed so that it does not come into contact with the flow sensor. The flow into or out fiom the borehole in the test section is the only flow that passes through the flow sensor. Instead of inflatable packers, rubber disks are used at both ends of the flow guide. These isolate the borehole section to be measured, see Figure 2.1. Groundwater level in the borehole is kept constant by using a special pump. The hydraulic head in the hole is then constant, since the hydraulic conductivity of the borehole is very high compared with the conductivity of bedrock. Consequently the difference in head over the rubber disks used in the flow guide is very small. The rubber disks are designed in such a way that they are always pressed against the borehole wall. Difference flow measurements differ fiom the conventional double packer tests in that there is no extra hydraulic pressure in the borehole section being measured. Constant hydraulic head in.the borehole implies that the water density in the hole is constant and that there are no losses due to fi-iction. If this is not the case, the hydraulic head at the measuring depth needs to be ascertained. A single difference flow measurement at one depth interval normally takes 12 minutes. This time includes waiting time for temperature stabilisation, a flow measurement by the thermal pulse method, a flow measurement by the thermal dilution method and lifiing of the cable to the next depth interval. The thermal dilution method is used to expand the range of measurement to include higher flow rates.

8 ., w Figure 2-1. Principles of difference flow measurement iii l

9 3 INTERPRETATION If measurements are carried out using two levels of potential in the borehole, then the hydraulic head in each of the sections and their conductivity can be calculated. It is assumed that a static flow condition exists. where Qnl and Qn2 are the measured flows in a section, Kn is hydraulic conductivity, a is a constant depending on the flow geometry, hl and h2 are the hydraulic heads in the hole ho is the head of the measured zone far Com the hole Since, in general, very little is known of.the flow geometry, cylindrical flow without skin zones is assumed. Cylindrical flow geometry is also justified because the borehole is at a constant head and there are no strong pressure gradients along the borehole, except at the ends of the borehole. For cylindrical flow, constant a is: where L is the length of the measured section, R is the distance to constant potential ho and ro is the radius of the hole. The distance to constant potential ho is not known and it must be chosen. Here R is chosen to be 14m. Hydraulic head and conductivity can be deduced Com the two measurements: where b = QnllQn2 Since the actual flow geometry is not known, calculated conductivity values should be taken as indicating orders of magnitude. As the calculated hydraulic heads do not depend on geometrical properties but only on the ratio of the flows measured at different heads in the borehole they should be less sensitive to unknown Cacture geometry.

10 4 EQUIPMENT SPECIFICATIONS The flowrneter monitors the flow of groundwater into or out from a borehole within a given section. A flow guide is used to separate the section to be measured. The flow guide maintains the section at the same hydraulic head as the rest of the hole. Groundwater flowing through the section is guided past the flow sensor. Flow is measured using the thermal pulse and thermal dilution methods. Measured values are sent in digital form to the PC computer. (Rouhiainen 1996). Type of instrument: Borehole diameters: Geometry of measurement: Method of flow measurement: Speed of measurement: Range of measurement: Additional measurements: Interpreted results: Winch: Logging computer : Pumps Total power consumption: Calibrated Method of calibration Difference Flow Meter. 56 mm, 66 mm and 76 mm. A variable length flow guide is used. Thermal pulse and thermal dilution methods. Depends the rate of i-lows to be measured mllmin. Temperature, single point resistance, fluid conductivity Hydraulic conductivity and hydraulic head. Mount Sopris Wna 10, 0.55 kw, 220V150Hz. Steel wire cable 1100 m, four conductors, Gerhard -Owen cable head. Depth determination is based on the marked cable (marks every 10m) and on the digital depth counter. PC, Windows 95 Software based on MS Visual Basic Digital data transmission RS485 The flow meter can be used in pumped or unpumped conditions. Borehole pumps are used to keep the GW level even during the measurements kw depending on the pumps March 1998 Special calibration pump for known, small and steady flows

11 5 RESULTS 5.1 Difference flow measiirement Measurement was begun in borehole R387 in pumped condition using ten metre section length. The aim was to measure the entire length of the borehole and to find the depths of measurable flows. Measurements continued using a two metre section length, but only at the depths where flow had been shown to exist in the ten metre measurements. In this way all the measurable flows were detected with two metre section length. Borehole R388 was measured completely with two metre section length. The results of these two metre measurements are presented in Appendices 1 (flow rates) and 2 (heads and conductivities) for borehole R387 and in Appendices 5 (flow rates ) and 6 (heads and conductivities) for borehole R388. The depths of the plotted results are presented fiom the ground surface to the middle point of the test section. Flow values in Appendices 1 and 5 are shown using a logarithrnic scale. The flows are shown in both directions, the ler hand side of each diagram represents flow out fiom the borehole within a test section and the right hand side represents flow into the borehole within a test section. Flows were measured using two different hydraulic heads in each borehole. The first water level in Appendices 1 and 5 was close to the natural groundwater level in the borehole, i.e. there was no or very little pumping into or out fiom the borehole. The other groundwater level was 1-5m below the non pumped level in the borehole. Hydraulic head and conductivity can be calculated fiom the flows using the method described in Chapter 3. Hydraulic head is presented in the plots if both of the flows at the sarne depth are not equal to zero. Hydraulic conductivity is presented if both or either of the flows are not equal to zero. The lower limit of the calculated conductivity depends on the lower limit of the flow range (6 rnlh), the difference between the heads used and on the section length. There are some points plotted on this line of estimated lower limit of conductivity. These indicate that both of the measured flows were below the lower detection lirnit (6 rnllh) of the flowrneter. There are error bars in the interpreted head and conductivity values. These error bars are obtained with the assumptions that there is always some error in the flow measurements and that this error sums up with the worst possible way in the interpretation (Rouhiainen 1996a-c). The error in measured flow is chosen to be 10% in the range of rnlh and then increasing linearly to 20% at mlh.

12 The pumping rates during the measurements are given in table 5.1. The two meter measurement was begun in pumped condition in borehole R388. All measurements were carried out fiom the bottom upwards. Table 5.1. Pumping rates Borehole R3 87 R3 87 R387 R3 87 R388 R388 Date Time 14:30 11:OO 20:30 13: Phase of measurement Pumping Pumping Pumping 'Nopumping" "No pumping" Pumping Depth of measurement (m) Pumping rate (llmin) Detailed flow and single point resistance logs A detailed flow logging was performed in the both boreholes with 10 cm point intervals. This method provides the depth and thickness of the conductive zones with a depth resolution of 10 cm. To make measurements more quickly, only the thermal dilution method was used for flow deterrnination. The section length chosen was one meter. This is why the width of a flow anomaly of a single fiacture is one meter. If the distance between leaky fiactures is less than one meter the anomalies will be overlapped. The depths of the plotted flow results are measured fiom the ground surface to the upper end of the test section. The electrode of the resistance tool is located within the upper rubber disks. The rubber disks obstruct both water and electric charge flow along the borehole. The results of the detailed flow and single point resistance logs are presented in Appendices for borehole R387 and in Appendices for borehole R388. The single point resistance logging was on during all the flow measurements. The logs of Appendix 3.1 and Appendices were measured during the ten meter measurements. For comparison, a repeated resistance log is presented in Appendix 3.2. It was measured during the detailed flow measurements.

13 The base level of the resistance curve in Appendix 3.2 is lower than the base level of the resistance curve in Appendix 3.1, specially in the lower part of the borehole. The electric conductivity of the water in the borehole rnay have been increased because of the pumping during the flow measurements. The resistance result in the lowest part of borehole R387 (Appendix 3.22) was taken fiom the detailed flow measurement because it reached nearer the bottom of the borehole. The resistance results in borehole R388 (Appendices ) were measured during the pumping phase of the two meter measurements. The depths of leaky fiactures are marked in the appendices of the detailed flow logs. 5.3 Temperature logs The temperature logs are presented in Appendices for borehole R387 and in Appendix 8 for borehole R388. The temperature logs are a by-product of,the difference flow measurement. The results were obtained during the two meter measurements. The anomalies of in-flowing cooler or warmer water can be seen in the temperature logs. The temperature is measured in the flow sensor. It rnay be possible to evaluate the inclination of flow fiom these anomalies. In practice, this rnay be dificult mainly because the measured temperature rnay not be the real temperature of the in-flowing water. If the flow is small the waiting time at one position rnay not be long enough to reach the final temperature. The temperature results are presented in both pumped and non pumped conditions. The temperature values in non pumped condition rnay also represent the out-flow from the borehole into the bedrock. In spite of the limitations mentioned, the temperature logs are presented because they could be useful in later interpretation. They also demonstrate the possibility of additional information if the measurements would be performed more carefully for chosen fiactures.

14 REFERENCES Rouhiainen P. 1996a. Difference Flow Measurements at the Romuvaara Site in Kuhmo, Boreholes KR1-4, KR7 - KR9, Work Report PATU Rouhiainen P. 1996b. Difference Flow Measurements at the Kivetty Site in Äänekoski, Boreholes KR1-3, KR5, KR8 and KR9, Work Report PATU Rouhiainen P. 1996c. Difference flow measurements at the Palmottu site in boreholes R385 and R386.The Palmottu Natural Analogue Project, Technical Report

15 APPENDICES Appendix 1. Appendix 2. Appendices Appendices Appendix 5. Appendix 6. Appendices Appendix 8. Borehole R387, flow rates, section length 2m Borehole R387, hydraulic heads and conductivities, section length 2m Borehole R387, detailed flow and single point resistance 1 ogs Borehole R387, temperature logs Borehole R388, flow rates, section length 2m Borehole R3 88, hydraulic heads and conductivities, section length 2m Borehole R388, detailed flow and single point resistance logs Borehole R3 88, temperature logs

16 15 Appendix 1 DIFFERENCE FLOW MEASUREMENT, LEGTH OF SECTION 2 M FLOW RATES PALMOTTU, BOREHOLE R387 0 Groundwater level in the borehole m below ground surface * 4.61 m below ground surface DEPTH (M) FLOW RATE (muh) OUT FROM HOLE 4 INTO HOLE

17 16 Appendix 2 DIFFERENCE FLOW MEASUREMENT, LENGTH OF SECTION 2 M RELATIVE PRESSURES AND HYDRAULIC CONDUCTIVITIES OF FRACTURES PALMOTTU, R387 ERROR BARS: ASSUMED ERROR OF FLOW 10-20% ASSUMED ERROR OF PRESSURE 10% DEPTH (M) E-II 1E-10 1E-9 IES 1E-7 1E-6 1E-5 RELATIVE PRESSURE (M) (0: 2= M) K (MIS)

18 17 Appendix 3.1 FLOW RATE AND SINGLE POINT RESISTANCE LOGS DEPTHS OF LEAKY FRACTURES PALMOTTU, R lllllll lllllll 1E+1 1E+2 1E+3 1E+4 1E+5 Flow rate (mlth) Single point resistance (ohm)

19 18 Appendix 3.2 FLOW RATE AND SINGLE POINT RESISTANCE LOGS, (REPEATED MEASUREMENT) DEPTHS OF LEAKY FRACTURES PALMOTTU, R387 1E+1 1E+2 1E+3 1E+4 1E+5 Flow rate (mlth) Single point resistance (ohm)

20 19 Appendix 3.3 FLOW RATE AND SINGLE POINT RESISTANCE LOGS DEPTHS OF LEAKY FRACTURES PALMOTTU, R387 1E+1 1E+2 1E+3 1E+4 1E+5 1E+6 1E+1 1E+2 1E+3 1E+4 1E+5 Flow rate (mllh) Single point resistance (ohm)

21 20 Appendix 3.4 FLOW RATE AND SINGLE POINT RESISTANCE LOGS DEPTHS OF LEAKY FRACTURES PALMOTTU, R387 1E+1 1E+2 1E+3 1E+4 1E+5 1E+6 1E+1 1E+2 1E+3 1E+4 1E+5 Flow rate (mlh) Single point resistance (ohm)

22 21 Appendix 3.5 FLOW RATE AND SINGLE POINT RESISTANCE LOGS DEPTHS OF LEAKY FRACTURES PALMOTTU, R E+1 1E+2 1E+3 1E+4 1E+5 1E+6 1E+1 1E+2 1E+3 1E+4 1E+5 Flow rate (mlih) Single point resistance (ohm)

23 FLOW RATE AND SINGLE POINT RESISTANCE LOGS DEPTHS OF LEAKY FRACTURES PALMOTTU, R387 Appendix 3.6 1E+1 1E+2 1E+3 1E+4 1E+5 1E+6 1E+1 1E+2 1E+3 1E+4 1E+5 Flow rate (mlk) Single point resistance (ohm)

24 23 Appendix 3.7 FLOW RATE AND SINGLE POINT RESISTANCE LOGS DEPTHS OF LEAKY FRACTURES PALMOTTU, R387 1E+1 1E+2 1E+3 1E+4 1E+5 1E+6 1E+1 1E+2 1E+3 1E+4 1E+5 Flow rate (mlth) Single point resistance (ohm)

25 24 Appendix 3.8 FLOW RATE AND SINGLE POINT RESISTANCE LOGS DEPTHS OF LEAKY FRACTURES PALMOTTU, R387 Flow rate (mlki) Single point resistance (ohm)

26 25 Appendix 3.9 FLOW RATE AND SINGLE POINT RESISTANCE LOGS DEPTHS OF LEAKY FRACTURES PALMOTTU, R387 1E+1 1E+2 1E+3 1E+4 le+s 1E+6 1E+1 1E+2 1E+3 1E+4 1E+5 Flow rate (mlh) Single point resistance (ohm)

27 26 Appendix 3.10 FLOW RATE AND SINGLE POINT RESISTANCE LOGS DEPTHS OF LEAKY FRACTURES PALMOTTU, R387 1E+1 1E+2 1E+3 1E+4 1E+5 1E+6 Flow rate (mllh) Single point resistance (ohm)

28 27 Appendix FLOW RATE AND SINGLE POINT RESISTANCE LOGS DEPTHS OF LEAKY FRACTURES PALMOTTU, R387 1E+1 1E+2 1E+3 1E+4 1E+5 1E+6 1E+1 1E+2 1E+3 1E+4 1E+5 Flow rate (mtih) Single point resistance (ohm)

29 28 Appendix 3.12 FLOW RATE AND SINGLE POINT RESISTANCE LOGS DEPTHS OF LEAKY FRACTURES PALMOTTU, R387 Flow rate (mlfh) Single point resistance (ohm)

30 29 Appendix 3.13 FLOW RATE AND SINGLE POINT RESISTANCE LOGS DEPTHS OF LEAKY FRACTURES PALMOTTU, R387 1E+1 1E+2 1E+3 1E+4 1E+5 1E+6 1E+1 1E+2 1E+3 1E+4 le+5 Flow rate (mllh) Single point resistance (ohm)

31 30 Appendix 3.14 FLOW RATE AND SINGLE POINT RESISTANCE LOGS DEPTHS OF LEAKY FRACTURES PALMOTTU, R387 1E+1 1E+2 1E+3 1E+4 1E+5 1E+6 1E+1 1E+2 1E+3 1E+4 1E+5 Flow rate (ml/h) Single point resistance (ohm)

32 31 Appendix 3.15 FLOW RATE AND SINGLE POINT RESISTANCE LOGS DEPTHS OF LEAKY FRACTURES PALMOTTU, R II:::-.. IIII... 1E+1 le+2 1E+3 1E+4 1E+5 1E+6 1E+1 1E+2 1E+3 1E+4 1E+5 Flow rate (ml/h) Single point resistance (ohm)

33 32 Appendix 3.16 FLOW RATE AND SINGLE POINT RESISTANCE LOGS DEPTHS OF LEAKY FRACTURES PALMOTTU, R387 1E+1 1E+2 le+3 1E+4 1E+5 1E+6 1E+1 1E+2 1E+3 1E+4 1E+5 Flow rate (mllh) Single point resistance (ohm)

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40 Appendix 4.1 TEMPERATURE OF WATER IN BOREHOLE DURING DIFFERENCE FLOW MEASUREMENT PALMOTTU R387 Groundwater level in the borehole 0.47 m below ground surface $i 4.61 m below ground surface O 9.O TEMPERATURE OF WATER IN THE BOREHOLE(CELS1US)

41 Appendix 4.2 TEMPERATURE OF WATER IN BOREHOLE DURING DIFFERENCE FLOW MEASUREMENT PALMOTTU R387 Groundwater level in the borehole 0.47 m below ground surface 4.61 m below ground surface / I I I I I I I I TEMPERATURE OF WATER IN THE BOREHOLE(CELS1US)

42 Appendix 4.3 TEMPERATURE OF WATER IN BOREHOLE DURING DIFFERENCE FLOW MEASUREMENT PALMOTTU R387 Groundwater level in the borehole m below ground surface 4.61 m below ground surface TEMPERATURE OF WATER IN THE BOREHOLE(CELS1US)

43 Appendix 4.4 TEMPERATURE OF WATER IN BOREHOLE DURING DIFFERENCE FLOW MEASWREMENT PALMOTTU R387 Groundwater level in the borehole 0.47 m below ground surface 4.61 m below ground surface I I I I l l i l t l l l l I I I I TEMPERATURE OF WATER IN THE BOREHOLE(CELS1US)

44 Appendix 4.5 TEMPERATURE OF WATER IN BOREHOLE DURING DIFFERENCE FLOW MEASUREMENT PALMOTTU R387 Groundwater level in the borehole m below ground surface 4.61 m below ground surface TEMPERATURE OF WATER IN THE BOREHOLE(CELS1US)

45 44 Appendix 5 DIFFERENCE FLOW MEASUREMENT, LEGTH OF SECTION 2 M FLOW RATES PALMOTTU, BOREHOLE R388 Groundwater level in the borehole m above ground surface * 3.99 m below ground surface DEPTH (M) FLOW RATE (m LIH) OUT FROM HOLE 4 INTO HOLE

46 45 Appendix 6 DIFFERENCE FLOW MEASUREMENT, LENGTH OF SECTION 2 M RELATIVE PRESSURES AND HYDRAULIC CONDUCTIVITIES OF FRACTURES PALMOTTU, R388 ERROR BARS: ASSUMED ERROR OF FLOW 10-20% DEPTH (M) E-11 1 E-10 1 E-9 1E-8 1E-7 1E-6 1E-5 RELATIVE PRESSURE (M) (0: 2= M) K (MIS)

47 46 Appendix 7.1 FLOW RATE AND SINGLE POINT RESISTANCE LOGS DEPTHS OF LEAKY FRACTURES PALMOTTU, R l 1 l ~ l 1 l E+1 1E+2 1E+3 1E+4 1E+5 1E+6 Flow rate (mlth) Single point resistance (ohm)

48 47 Appendix 7.2 FLOW RATE AND SINGLE POINT RESISTANCE LOGS DEPTHS OF LEAKY FRACTURES PALMOTTU, R388 1E+1 1E+2 le+3 1E+4 1E+5 1E+6 Flow rate (mllh) 1E+1 le+2 1E+3 1E+4 1E+5 Single point resistance (ohm)

49 48 Appendix 7.3 FLOW RATE AND SINGLE POINT RESISTANCE LOGS DEPTHS OF LEAKY FRACTURES PALMOTTU, R i i inm I I iiir -...%::..:... le+1 1E+2 le+3 le+4 1E+5 le+6 1 E+l 1E+2 le+3 1E+4 1E+5 Flow rate (mllh) Single point resistance (ohm)

50 49 Appendix 7.4 FLOW RATE AND SINGLE POINT RESISTANCE LOGS DEPTHS OF LEAKY FRACTURES PALMOTTU, R388 1E+1 le+2 1E+3 1E+4 1E+5 1E+6 1E+1 1E+2 1 E+3 1E+4 1E+5 Flow rate (mlth) Single point resistance (ohm)

51 50 Appendix 7.5 FLOW RATE AND SINGLE POINT RESISTANCE LOGS DEPTHS OF LEAKY FRACTURES PALMOTTU, R388 1E+1 1E+2 1E+3 1E+4 1E+5 1E+6 1E+1 1E+2 1E+3 1E+4 1E+5 Flow rate (mlk) Single point resistance (ohm)

52 51 Appendix 7.6 FLOW RATE AND SINGLE POINT RESISTANCE LOGS DEPTHS OF LEAKY FRACTURES PALMOTTU, R I I iirm I I iiiiii I i iiiiii i i iiiii i i iim 1E+1 1E+2 1E+3 1E+4 1E+5 1E+6 1E+1 1E+2 1E+3 1E+4 1E+5 Flow rate (rnlh) Single point resistance (ohm)

53 Appendix 8 TEMPERATURE OF WATER IN BOREHOLE DURING DIFFERENCE FLOW MEASUREMENT PALMOlTU R388 Groundwater level in the borehole 0.08 m above ground surface m below ground surface -- I I I I I I I I I I I I / I I TEMPERATURE OF WATER IN THE BOREHOLE(CELS1US)