973 GEOCHEMICAL PRESSURE OF COAL ASH AND DUST ON THE SOIL ECOLOGY OF KYUSTENDIL VALLEY Anton Sotirov Abstract: All type of coals used for heating or for the production n of electricity in Kyustendil valley has an increased ash content and exceeds the Clark contents of the elements and their oxides in the coal, and all to a lesser or higher degree is rich in harmful substances. The main problem is the use of coal for heating in winter by the local population, the burning of any type of waste and the disposal of the ashes anywhere in the environment. Therefore, the described elements and oxides exert high geochemical pressure on the soil ecology in the Kyustendil valley for the last 100 years. The wind roses of the winds and the entrance, especially the exit of the Struma River, help a lot for the natural cleansing of the valley, as well as the natural geochemical barriers that are the slopes of the mountains around. Keywords: geochemistry, coal, soil, ecology, contamination, ash Introduction Location. Town of Kyustendil is located in South-West Bulgaria, Lat.: 42°16'N / Lon.: 22°41'E / Altitude: 527 m, Timezone: Europe/Sofia (UTC+2). It is settled in the Kyustendil Pliocene Valley, which is fenced by the mountains Osogovo from the South, Lisets and Chudinska from West and North-West, Zemenska from the North and Konyavska from the North- East and East. It is connected to the neighboring valleys by gorges. It is drained by the Struma River and its tributaries, that flows into the Mediterranean Sea (Fig. 1). N SERBIA North MACEDONIA GREECE TURKEY BLACK SEA M: 45 km ROMANIA Danube River Sofia Varna Burgas Plovdiv 8 Kyustendil Studied Area BULGARIA Major Ash and Dust Flows Secondary Ash and Dust Flows Fig. 1. Location of the studied area and major and second ash and dust air flows, town of Kyustendil, SW Bulgaria