Southern Finland Office 100/2012 Espoo

Transcription

1 Southern Finland Office 100/2012 Espoo Environmental statement for the Kedonojankulma (8304/1), Kedonojankulma 2 (8775/1), Kedonojankulma 3 (9008/1) and Kedonojankulma 4 (9328/1) claim areas in Jokioinen, Southern Finland Tarja Hatakka and Markku Tiainen

2 the Kedonojankulma,the Kedonojankulmaa 2, the Kedonojankulma 3 and the Kedonojankulmaa 4 claim areas in Jokioinen, Southwestern Finland GEOLOGICAL SURVEY OF FINLAND Authors Tarja Hatakka, Markku Tiainenn DOCUMENTATION PAGE Date / Rec. no Type of report Archive report Title of report Environmental statement for the Kedonojankulma (8304/1), Kedonojankulma 2 (8775/1), Kedonojankulma 3 (9008/1) and Kedonojankulma 4 (9328/1) claim areas in Jokioinen, Southern Finland Abstract This report on the environmental statement for the Kedonojankulma claim areas, Kedonojankulma (8304/1), Kedonojankulma 2 (8775/1), Kedonojankulma 3 (9008/1) and Kedonojankulma 4 (9328/1), presents the environmental conditions and geochemical baselines in the claim areas in There is no settlement inside the Kedonojankulma claim areas, but two farms are surrounded by the claim areas and nine farms are in close proximity to the claim areas. The bedrock of the claim areas consists of multiphase highlevel porphyritic tonalite, called Kedonojankulma tonalite, surrounded by intermediate volcanics and mica schists. Quaternary deposits in the claim areas are mainly comprised of clay and sandy till, and southwest of the Kedonojankulma 3 and the Kedonojankulma 4 is a sand and gravel formation. The thickness of the Quaternary deposits ranges between 1.5 m and 34.1 m. The Vuohenoja stream gathers the surface waters of the claim areas and empties into the Koijoki River, later also called the Koenjoki River and the Kojonjoki River. The Kojonjoki River empties into the Loimijoki River, which empties into the Kokemäenjoki River in the municipality of Huittinen. The groundwater of the claim areas flows in the same direction as the surface water. There are no groundwater aquifers classified as important or suitable for water supply in the Kedonojankulma and the Kedonojankulma 2 areas. The Kedonojankulma 3 and the Kedonojankulma 4 claim areas are next to the Latovainioo gravel formation, which is classified as important or suitable for water supply ( ). There are no conservation areas in the Kedonojankulma claim areas, and no endangered animal or plant species or monuments of antiquity have been reported. GTK has taken some till, stream sediment, stream water and groundwater samples for geochemical analysis from the Kedonojankulma claim areas and their surroundings. Arsenic concentrations in soils, organic stream sediment, surface waters and groundwater from the claim areas are on average higher than in the nearby areas or in the whole of Finland. The average arsenic concentrations in soils from the claim areas were found to be higher than the threshold value for arsenic, 5 mg/kg, given in the Decree on the Assessment of Soil Contamination and Remediation Needs (214/2007). Arsenic concentrations in the groundwater of the boreholes from the claim areas exceed the upper permissible concentration for household water, 10 µg/l, set by the Ministry of Social Affairs and Health (STM Decree 401/2001). Tills, organic stream sediment and surface waters from the claim area and its surroundings contain more copper than the comparison materials. The surface water and groundwater from the claim areas are slightly acidic or alkaline and their bicarbonate, sulphate and magnesium concentrations were found to be higher than in the near surroundings. Keywords Environment, Bedrock, Quaternary deposits, Geochemical baseline, Till, Stream sediment, Stream water, Groundwater Geographical area Finland, Jokioinen Map sheet Other information Commissioned by GTK Report serial Archive code 100/2012 Total pages 22 Language English Price Confidentiality Confidential

3 and the Kedonojankulma 4 claim areas in Jokioinen, Southwestern Finland Unit and section Southern Finland Office/ Land Use and Environment Signature/name Tarja Hatakka Project code Signature/name Markku Tiainen

4 and the Kedonojankulma 4 claim areas in Jokioinen, Southwestern Finland Contents Documentation page 1 INTRODUCTION 2 GENERAL DESCRIPTION OF THE STUDY AREA 3 BEDROCK OF THE SURROUNDINGS KEDONOJANKULMA CLAIM AREAS AND 4 QUATERNARY DEPOSITS OF THE KEDONOJANKULMA CLAIM AREAS AND SURROUNDINGS CATCHMENT AREAA AND CURRENT FLOW DIRECTIONS OF WATER 6 6 CONSERVATION AREAS 7 CHEMICAL COMPOSITION OF TILL, STREAM SEDIMENT, SURFACE WATER AND GROUNDWATER IN THE KEDONOJANKULMA CLAIM AREAS AND THEIR SURROUNDINGS 8 SUMMARY REFERENCES

5 and the Kedonojankulma 4 claim areas in Jokioinen, Southwestern Finland 1 1 INTRODUCTION The Geological Survey of Finland (GTK) generates Mineral Deposit Reports based on the studies and results of its exploration projects carried out in claim areas. These reports are sent to the Ministry of Employment and the Economy after the investigations of the claim area are completed. Since the beginning of the 21 st century, some relevant environmental information on the claim area has been attached to these reports. Usually, more environmental information on the claim area exists than is feasible to include in the Mineral Deposit Report. This report on the environmental statement for the Kedonojankulma (8304/1), Kedonojankulma 2 (8775/1), Kedonojankulma 3 (9008/1) and Kedonojankulma 4 (9328/1) claim areas in Jokioinen, Southern Finland, presents the environmental conditions and geochemical baselines in the study area in GENERAL DESCRIPTION OF THE STUDY AREA The Kedonojankulma claim areas [Kedonojankulma (8304/1), Kedonojankulma 2 (8775/1), Kedonojankulma 3 (9008/1) and Kedonojankulma 4 (9328/1)] are located in the municipality of Jokioinen in southern Finland (Fig. 1). Figure 1. The Kedonojankulma claim areas in southern Finland.

6 and the Kedonojankulma 4 claim areas in Jokioinen, Southwestern Finland 2 The Kedonojankulma claim areas are dominated by areas under cultivation (Fig. 2). Small hills covered with glacial till surround the fields outside of the claim areas. North of the claim areas, in Kuuma, the highest till hill is m a.s.l., and inside the claim areas and in the east the hills are about 120 m a.s.l. The fields inside the claim areas are about m a.s.l. A road passes the northernmost claim areas from southwest to northeast to the farms Jokihaara and Saari, and side roads from northwest to southeast to the farms Seppälä and Kivisaari and to the farms Kantola, Kedonoja and KorpiMattila (Fig. 4). There is no settlement in the Kedonojankulma claim areas, but the abovementioned farms Seppälä and Kivisaari are surrounded by the Kedonojakulma claim areas. Furthermore, the farms Koivurinne, Koivumäki, Jokihaara and Saari in the north, Kedonoja and KorpiMattila in the west and Kiviniemi farm in the south, as well as Niihapää farm in the southwest and Koivurinne farm in the east, are located in the close proximity to the claim areas (Fig. 4). The agricultural lands in the Kedonojankulma claim areas are comprised of cornfields and hayfields. According to the topographic map of the claim area, there are no lakes or ponds. The small Vuohenoja stream, which gathers waters from its environs, flows from southwest to northeast. The stream empties into the Koijoki River northeast of the claim area. The Koijoki River, which westwards is called the Koenjoki River and the Kojonjoki River, empties into the Loimijoki River at Koskenkylä in Alastaro, in the municipality of Loimaa. The Loimijoki River empties into the Kokemäenjoki River in the municipality of Huittinen. Figure 2. The Kedonojankulma claim areas are dominated by areas under cultivation. Photograph: T. Hatakka.

7 and the Kedonojankulma 4 claim areas in Jokioinen, Southwestern Finland 3 3 BEDROCK OF THE KEDONOJANKULMA CLAIM AREAS AND SURROUNDINGS The Kedonojankulma claim areas are located in the Palaeoproterozoic volcanicintrusive Häme belt in southern Finland. There is a mineral occurrence in the claim areas that is hosted by a highlevel tonalitic granitoid intrusion comprising evengrained tonalite, porphyritic tonalite, quartzplagioclase porphyryy and finegrained hydrothermally altered rock types (Fig. 3). There are several outcrops in the claim areas that are composed of quartzplagioclase porphyry. All other information is based on the drilling data. The Kedonojankulma occurrence has a complex mineralogy, including various copper, silver, gold, bismuth, molybdenum, antimony, tin, zinc and lead minerals. Major ore minerals include chalcopyrite, arsenopyrite, bornite, chalcocite, sphalerite and pyrite. 4 QUATERNARY DEPOSITS OF THE KEDONOJANKULMA CLAIM AREAS AND SURROUNDINGS Quaternary deposits in the Kedonojankulma claim areas consist of clay and till (Fig. 4). Hills covered with glacial till surround the clay fields. The till deposits in the claim areas are covered with clay. The till type is sandy till. In the southwestern part of the Kedonojankulma claim areas, there is a northsouthoriented esker composed of sand and gravel. According to drillings in the Kedonojankulma claim areas, the thickness of Quaternary deposits ranges between 1.5 m and 34.1 m. The thickest layers are around the Vuohenoja stream, where the side road to the Korpi Mattila farm begins. There is an important sand and gravel formation providing a water supply in the southwestern parts of the Kedonojankulma 3 and Kedonojankulma 4 claim areas (Fig. 5). This Latovainio groundwater reservoir ( ) has been classified as important for water supply. According to the topographic map, there are no springs in the claim areas. Artesian groundwater appears in the claim areas, where the clay layers are thickest: groundwater from an approximately 70mdeep borehole flows to the ground surface under its own pressure.

8 and the Kedonojankulma 4 claim areas in Jokioinen, Southwestern Finland 4 Figure 3. Bedrock map of the Kedonojankulma claim areas.

9 and the Kedonojankulma 4 claim areas in Jokioinen, Southwestern Finland 5 Figure 4. Quaternary map of the Kedonojankulma claim areas.

10 and the Kedonojankulma 4 claim areas in Jokioinen, Southwestern Finland 6 5 CATCHMENT AREA AND CURRENT FLOW DIRECTIONS OF WATER The Kedonojankulma claim areas do not have a catchment basin of their own, but they form part of a larger catchment area (Fig. 6). From the southwest to the northeast flows the Vuohenoja stream, which gathers surface waters from its environs. The Vuohenoja stream empties into the Koijoki River in the northeast. The Koijoki River, which westwards is called the Koenjoki River and the Kojonjoki River, empties into the Loimijoki River at Koskenkylä in Alastaro, in the municipality of Loimaa. The Loimijoki River empties into the Kokemäenjoki River in the municipality of Huittinen. According to the bedrock topography based on diamond core drillings (Fig. 7), there is a depression on the bedrock surface around the Vuohenoja stream, where the side road to the east begins. Groundwater flows in this direction, and the flow direction is the same as that of surface waters (Fig. 6). In the Latovainio sand and gravel formation, which is classified as important for water supply ( ), the groundwater flow direction is from north and from south towards the Jänhijoki River (OIVA Ympäristö ja paikkatietopalvelu ), which empties into the Loimijoki River. 6 CONSERVATION AREAS There are no conservation areas in the Kedonojankulma claim areas (Fig. 8). The closest protected area is the Peiliössuo mire, about 1.2 km to the west of the claim areas. The KaakkosuoKivijärvi protected area (FI ), about 8 km to the northwest of the claim areas, belongs to the EU Natura 2000 network of protected areas. Two valuable bedrock areas are located about 5.5 km to the southwest and 7 km to the north of the claim area. One small protected area of private lands is located 8.5 km to the southeast of the claim area. No endangered animal or plant species or monuments of antiquity have been reported in the Kedonojankulma claim areas.

11 and the Kedonojankulma 4 claim areas in Jokioinen, Southwestern Finland 7 Figure 5. A groundwater area important for water supply (Latovainio ) in the Kedonojankulma claim areas and their surroundings.

12 and the Kedonojankulma 4 claim areas in Jokioinen, Southwestern Finland 8 Figure 6. Catchment area of surface water and groundwater in the Kedonojankulma claim areas and their surroundings, and flow directions of surface waters and groundwater.

13 and the Kedonojankulma 4 claim areas in Jokioinen, Southwestern Finland 9 Figure 7. Bedrock topography according to diamond core drillings in the Kedonojankulma claim areas.

14 and the Kedonojankulma 4 claim areas in Jokioinen, Southwestern Finland 10 Figure 8. Protected areas belonging to the EU Natura 2000 network of protected areas and other protected areas in the surroundings of the Kedonojankulma claim areas.

15 and the Kedonojankulma 4 claim areas in Jokioinen, Southwestern Finland 11 7 CHEMICAL COMPOSITION OF TILL, STREAM SEDIMENT, SURFACE WATER AND GROUNDWATER IN THE KEDONOJANKULMA CLAIM AREAS AND THEIR SURROUNDINGS GTK took 421 till samples for geochemical analysis from the Kedonojankulma claim areas (Fig. 9) during an exploration project in (Tiainen 2012). The median concentrations of some elements in these samples (<0.06 mm and <2 mm grain sizes, aquaa regia extraction) are presented in Table 1. GTK has also taken till samples around the Kedonojankulma claim areas in a regional geochemical mapping project (Fig. 10) (Salminen 1995), and one clay sample about 3.5 km to the west of the claim area in a targeted geochemical mapping project. The median concentrations of some elements in the till samples (<0.06 mm grain size, aqua regia extraction) and some elements in the clay sample (<2 mm grain size, aqua regia extraction) are presented for comparison in Table 1. The median values of some elements in till samples from the volcanicsedimentary belt of southern and southwestern Finland (Koljonen 1992) and the threshold values given in the government s Decree on the Assessment of Soil Contamination and Remediation Needs (214/2007) are also presented. The median concentration of arsenic in subsoil samples from the Kedonojankulma claim area is on average higher than the arsenic concentrations in tills from southern and southwestern Finland (Table 1). The median concentration is also above the threshold value for arsenic, 5 mg/kg, given in the government s Decreee on the Assessment of Soil Contamination and Remediation Needs (214/2007). The copper concentrations were found to be higher in the soils from the claim area than on average in regional and reconnaissance scale mapping.

16 and the Kedonojankulma 4 claim areas in Jokioinen, Southwestern Finland 12 Figure 9. Soil samples taken in the Kedonojankulma claim areas.

17 and the Kedonojankulma 4 claim areas in Jokioinen, Southwestern Finland 13 Figure 10. Till samples taken in and around the Kedonojankulma claim areas in the regional geochemical mapping project (Salminen 1995).

18 and the Kedonojankulma 4 claim areas in Jokioinen, Southwestern Finland 14 Table 1. The median concentrations of some elements in the fine fraction of till (< 0.06 mm and <2 mm, aqua regia extraction) in the Kedonojankulma claim areas, the median values of some elements in the till samples around the Kedonojankulma claim areas (GTK regional till geochemical mapping data 2011), the median values of elements in the fine fraction of till (< 0.06 mm, aqua regia extraction) in volcanicthe threshold values (for sedimentary belt of southern and southwestern Finland (Koljonen 1992), and <2 mm grain size and for AR extraction) given in the Decree on the Assessment of Soil Contamination and Remediation Needs (VnA 214/2007). Element Till mapping of the Kedonojankulma claim areas Targeting geochemical soil mapping, samples Regional geochemical till mapping close to the <0.06 mm <0.06 mm <2 mm Kedonojankulma claim areas <2 mm Median mg/kg Median mg/kg Till mg/kg Clay mg/kg Median mg/kg Ag < As Au Bi Cd 0.13 < Co Cr Cu Mo 1.0 < Ni Pb 6.5 < S Sb 0.20 <20 < V Zn , Number of samples Reconnaissance scale till mapping, Southern Finland <0.06 mm Threshold value given in the Decree (214/2007) for <2 mm Median mg/kg mg/kg GTK has taken one organic stream sediment sample about 7 km to the southwest of the Kedonojankulma claim areas, in a regional stream sediment and stream water geochemical mapping project in 1990 (Lahermo et al. 1996). Some element concentrations in the stream sediment sample and for comparison the median values of some elements in stream sediments for the whole of Finland in 1990 are presented in Table 2. Silver, arsenic, bismuth and copper concentrations were found to be clearly higher in the stream sediment sample close to the claim area than in stream sediments on average in Finland (Table 2). There is also more cadmium, chromium, nickel, lead, vanadium and zinc in the stream sediment near the claim area.

19 and the Kedonojankulma 4 claim areas in Jokioinen, Southwestern Finland 15 Table 2. Some element concentrations in organic stream sediment samples close to the Kedonojankulma claim areas and the median values of some elements in organic stream sediment in Finland in 1990 (Lahermo et al. 1996). Ag As Bi Cd Co Cr Cu Hg Mo Ni Pb S Sb V Zn Number of samples Stream sediment close to the Kedonojankulma claim areas mg/kg Stream sediment from the whole of Finland, Median mg/kg GTK took two surface water samples from the catchment of the Kedonojankulma claim area in July 2011 and three samples in October 2012 (Fig. 11). Four stream water samples were taken from small streams that empty into the Vuohenoja stream (Figs 11 and 12). One surface water sample was taken from the Koijoki River (Figs 11 and 13). GTK also took one stream water sample about 7 km to the southwest of the Kedonojankulma claim area in a regional stream sediment and stream water geochemical mapping project in 1990 (Lahermo et al. 1996). Some element concentrations and properties in these water samples, as well as median concentrations of some elements in stream water for the whole of Finland in 1990, are presented in Table 3. The stream waters in the Kedonojankulma claim areas are slightly acidicc or alkaline and they contain more dissolved compounds than the stream waters on average in Finland (Table 3). Bicarbonate, sulphate and magnesium concentrations were found to be higher, and there is also more silver, arsenic, cobalt, copper and manganese in the stream waters from the claim areas.

20 and the Kedonojankulma 4 claim areas in Jokioinen, Southwestern Finland 16 Figure 11. Sampling sites for surface water and groundwater in the catchment of the Kedonojankulma claim areas in 2011 and in 2012.

21 Environmental statement of the Kedonojankulma,the Kedonojankulma 2, the Kedonojankulma Ke 3 and the Kedonojankulma 4 claim areas in Jokioinen, Southwestern Finland 17 Figure 12. A stream water sample was taken from a small stream in the Kedonojankulma claim area (8304/1) close to the Vuohenoja stream in July Photograph: Photo : T. Hatakka. Figure 13. Sampling site for surface s water taken from Koijoki River iver downstream of the Kedonojankulma claim areass in July Photograph: T. Hatakka.

22 and the Kedonojankulma 4 claim areas in Jokioinen, Southwestern Finland 18 Table 3. Some element concentrations and properties in surface waters in the Kedonojankulma claim area (8304/1) and its surroundings in 1990 and in 2011, and the median values of some elements and properties in stream water in Finland in 1990 (Lahermo & al. 1996). Element or property Stream waters, catchment of Kedonojankulma claim areas and ph Electric conductivity River water, Koijoki river Stream water, close to the Kedonojankulma claim area ms/m 25 o C HCO 3 mg/l SO 2 4 mg/l NO 3 mg/l Cl mg/l Ca mg/l Mg mg/l Na mg/l K mg/l Ag µg/l Al µg/l Stream water, Finland in 1990 Median < As µg/l Bi µg/l < <0.02 <0.03 Co µg/l Cr µg/l Cu µg/l Fe mg/l Mn mg/l Mo µg/l Ni µg/l Pb µg/l Sb µg/l V µg/l Zn µg/l Number of samples < As there are no springs or household wells in the Kedonojankulma claim areas, GTK has taken and analysed groundwater samples from two boreholes, located in the claim areas, in July and August 2011 (Figs 11 and 14) and from a groundwater pond located in close proximity to the claim areas Kedonojankulma 3 and Kedonojankulma 4 in October 2012 (Figs 11 and 15). The pond is in the Latovainio sand and gravel formation, which has been classified as important for water supply (Latovainio ). There is a water intake in the Kuuma village, where the

23 and the Kedonojankulma 4 claim areas in Jokioinen, Southwestern Finland 19 groundwater quality is regularly monitored (OIVA Ympäristö ja paikkatietopalvelu ). GTK took 13 groundwater samples from the topographic map sheet area in which the Kedonojankulma claim areas are located ( ) in (GTK geochemical groundwater database 2012). Nine of the samples were taken from drilled bedrock wells and four from dug wells. The median concentrations of some elements and properties in these samples, as well as the concentrations and properties in groundwater from the boreholes, from the groundwater pond and from the Kuuma water intake, are presented in Table 4. Figure 14. Groundwater samples were taken from boreholes (Borehole 2) in the Kedonojankulma claim area (8304/1) in July and August Photograph: T. Hatakka. Figure 15. A groundwater pond in close proximity to the Kedonojankulma claim areas. A groundwater sample from the pond was taken in October Photograph: T. Hatakka.

24 and the Kedonojankulma 4 claim areas in Jokioinen, Southwestern Finland 20 Table 4. Some element concentrations and properties in the groundwater from boreholes in the Kedonojankulma claim areas, from a groundwater pond in the Latovainio esker, and the median values of elements and properties in groundwater from the Kuuma groundwater intake and from bedrock wells and dug wells in the topographic map sheet area ( ), where the Kedonojankulma claim areas are located (GTK geochemical groundwater database 2012), and the upper permissible and recommended concentrations and target values for household water set by the Ministry of Social Affairs and Health (STM Decree 401/2001). Element or property Boreholes 1 and 2 the Kedonojankulma claim areas and ph Electrical conductivity ms/m 25 o C HCO 3 mg/l SO 4 2 mg/l NO 3 mg/l <0.2 Cl mg/l Ca mg/l Mg mg/l Na mg/l K mg/l Ag µg/l <0.01 Al µg/l < As µg/l Bi µg/l <0.02 Co µg/l < Cr µg/l < Cu µg/l < Fe mg/l Mn µg/l Mo µg/l Ni µg/l Pb µg/l <0.05 Sb µg/l < V µg/l <0.05 Zn µg/l Number of samples 2 Groundwater pond in the Latovainio sand and gravel formation Kuuma water intake, tap Median Dug wells in topographic map sheet area in Median < < <0.01 < <0.02 < < Bedrock wells in Upper topographic permissible or map sheet recommended area concentration in for household water Median (STM 401/2001) < < < The groundwater from the boreholes of the Kedonojankulma claim area is alkaline and it contains more dissolved compounds than the groundwater from the bedrock wells in the same topographic map sheet area. Bicarbonate, sulphate, chloride, calcium and magnesium concentrations in groundwater were found to be higher in the claim areas. Arsenic concentrations in the borehole waters are clearly higher than those in groundwater from the Latovainio sand and gravel formation. The arsenic concentrations in the borehole waters exceed the upper permissible concentration for household water, 10 µg/l, set by the Ministry of Social Affairs and Health (Decree 401/2001).

25 and the Kedonojankulma 4 claim areas in Jokioinen, Southwestern Finland 21 8 SUMMARY There is no settlement inside the Kedonojankulma (8304/1), Kedonojankulma 2 (8775/1), Kedonojankulma 3 (9008/1) or Kedonojankulma 4 (9328/1) claim areas, but in close proximity there are 11 farms. The bedrock of the claim area is composed of a highlevel volcanic schists of the Häme belt. In the Kedonojankulma tonalitic granitoid complex intruding the intermediate claim area there is a CuAuAg(MoAs) mineralization, which occurs as a finegrained sulphide dissemination, mainly in the hydrothermally altered part of the porphyritic tonalite and quartz in the claim areas are plagioclase porphyry phases of the tonalitic intrusion. Quaternary deposits mainly comprised of clay and sandy till, and there is a sand and gravel formation southwest of the Kedonojankulma 3 and Kedonojankulma 4 claim areas. The thickness of Quaternary deposits ranges between 1.5 m and 34.1 m. The Vuohenoja stream gathers the surface waters of the claim area. The stream empties into the Koijoki River, later also called the Koenjoki River and the Kojonjoki River, which empties into the Loimijoki River. The Loimijoki River empties into the Kokemäenjoki River in the municipality of Huittinen. Groundwater of the claim areas flows in the same direction as the surface water. The Latovainio sand and gravel formation, next to the claim areas, has been classified as important for water supply (Latovainio ). There is a water intake in the village of Kuuma. There are no conservation areas in the Kedonojankulma claim areas, and no endangered animal or plant species or monuments of antiquity have been reported. The average arsenic concentrations in soils, in organic stream sediment, in surface waters and in groundwater were found to be higher in the Kedonojankulma claim areas than on average in Finland and in the nearby areas. The average arsenic concentrations in soils in the claim areas are higher than the threshold value for arsenic, 5 mg/kg, given in the Decreee on the Assessment of Soil Contamination and Remediation Needs (214/2007). The arsenic concentrations in the groundwater from the boreholes in the claim areas exceed the upper permissible concentration for household water, 10 µg/ /l, set by the Ministry of Social Affairs and Health (STM Decree 401/2001). Tills, organic stream sediment and surface waters from the claim areas or their surroundings contain more copper than the comparison materials. The surface water and the groundwater in the claim area are slightly acidic or alkaline and their bicarbonate, sulphate and magnesium concentrations are higher than the waters from the near surroundings. REFERENCES The Decree on the Assessment of Soil Contamination and Remediation Needs (214/2007). (Valtioneuvoston asetus maaperän pilaantuneisuuden ja puhdistustarpeen arvioinnista (214/2007) ). Koljonen, T Resultss of the mapping. In: Koljonen, T. (ed.) Suomen geokemian atlas, osa 2: moreeni The Geochemical Atlas of Finland, Part 2: Till. Geological Survey of Finland, Espoo, pp

26 and the Kedonojankulma 4 claim areas in Jokioinen, Southwestern Finland 22 Lahermo, P.; Väänänen, P.; Tarvainen, T.; Salminen, R Suomen geokemian atlas. Osa 3 : Ympäristögeokemia purovedet ja sedimentit = Geochemical atlas of Finland. Part 3 : Environmental geochemistry stream waters and sediments. Espoo: Geologian tutkimuskeskus. 149 p. OIVA Ympäristö ja paikkatietopalvelu. Finnish Environmental Center. /scripts/oiva.asp Salminen, R. (toim.) Alueellinen geokemiallinen kartoitus Suomessa vuosina Espoo: Geologian tutkimuskeskus, Tutkimusraportti 130, 47 s. (English summary: Regional Geochemical Mapping in Finland in ). STM Decree 401/2001. Sosiaali ja terveysministeriön asetus pientenn yksiköiden talousveden laatuvaatimuksista ja valvontatutkimuksista. Suomen säädöskokoelma, N:o 401/ s. + 3 liitettä. Tiainen, M.; Kärkkäinen, N Till geochemical exploration of the Kedonojankulma Cu Archive report Au deposits in Jokioinen, Southern Finland. Geological Survey of Finland, 56/ p. Valtioneuvoston asetus maaperän pilaantuneisuuden ja puhdistustarpeen arvioinnista (214/2007) (The Decree on the Assessment of Soil Contamination and Remediation Needs (214/2007).