the value of improvement in air quality by reducing sulfur dioxide gas (so2) emitted from sarcheshmeh copper complex: one-and-one-half-bound dichotomous choice contingent valuation approach

sarcheshmeh copper complex is one of the largest industrial-mining complexes in the world and is the largest copper producer in iran. despite this, a huge amount of so2 gas is produced and enters the environment in this complex. therefore, this study investigates the value of improvement in air quality and estimates the marginal willingness to pay curve. for this purpose, oohb dccv method has been used. a sample of 2158 households was chosen, based on the stratified sampling method. the respondents’ wtp was then elicited through a series of face-to-face interviews. results showed that 87.3% of the respondents were able to express a positive wtp for the reduction of so2 emission from this complex and the improvement in air quality worth 719252.75$ for the regional people. estimated marginal willingness to pay curve has a rising positive slope. this curve can be a useful tool for policy makers on the use of economic instruments (e.g. tax and subsidies) to control this pollutant.