Assessing Spatial Occurrence of Ground Level Ozone around Coal Mining Areas of Chandrapur District, Maharashtra, India Pradeep R. Salve & Deepty Ranjan Satapathy & Yashwant B. Katpatal & Satish R. Wate Received: 15 June 2006 / Accepted: 24 October 2006 / Published online: 8 February 2007 # Springer Science + Business Media B.V. 2007 Abstract Stratospheric input and photochemical ozone formation in the troposphere are the two main sources determining the ozone levels in the surface layer of the atmosphere. Because of the importance of ozone in controlling the atmospheric chemistry and its decisive role in the heat balance of atmosphere, leading to climate change, the examination of its formation and destruction are of great interest. This study characterized the distribution of Ground level Ozone (GLO) in Chandrapur district is lying between 19°25′N to 20°45′N and 78°50′E to 80°10′E. Contin- uous ozone analyzer was used to quantify GLO at thirteen locations fixed by Global Positioning System (GPS) during the winter of 2005–2006. The daily GLO at all the locations ranged between 6.4 and 24.8 ppbv with an average and standard deviation of 14.9±6.5 ppbv. The maximum and minimum concen- tration occurs during 1300–1600 h and 0300–0500 h may be due to high solar radiation facilitating photochemical production of O 3 and downward mixing from the overlying air mass and in situ destruction of ozone by deposition and/or the reaction between O 3 and NO. GIS based spatial distribution of GLO in Chandrapur district is indicates that the central core of the district and southern sites experi- enced elevated levels of GLO relative to the northern and western areas. The sites near by Chandrapur city are particularly affected by elevated GLO. The average variation of GLO with temperature shows a significant correlation of r =0.55 indicating a direct relationship between GLO and temperature. Similarly an attempt has been made to compare the GLO monitored data in Chandrapur district with the reported values for other locations in Indian cities. This generated database helps regulatory agencies to identify locations where the natural resources and human health could be at risk. Keywords Diurnal variation . GIS mapping . GLO 1 Introduction Ground-level ozone (GLO) is a secondary air pollut- ant formed by photochemical reactions involving oxides of nitrogen (NO x ) and VOCs, mainly hydro- carbons. In the presence of solar radiation, nitrogen dioxide (NO 2 ) dissociates to form nitric oxide (NO) and an oxygen atom (O). Ozone (O 3 ) is then formed by molecular oxygen (O 2 ) reacting with the oxygen atom (O). However, when hydrocarbons are present, Environ Monit Assess (2007) 133:87–98 DOI 10.1007/s10661-006-9562-5 P. R. Salve (*) : D. R. Satapathy : S. R. Wate Environmental Impact & Risk Assessment Division, National Environmental Engineering Research Institute, Nehru Marg, Nagpur 440020 (M.S), India e-mail: salvepr1@rediffmail.com Y. B. Katpatal Department of Civil Engineering, Visvesvaraya National Institute of Technology (VNIT), Nagpur, India