This study monetizes spillover effects of soil and groundwater contaminated sites using a quantile hedonic price model for different site types in Taoyuan City in Taiwan, which has 1664 sites, the highest number for any city in Taiwan. The results show that except for those living in the cheapest housing, most residents are willing to pay a higher price to live farther away from contaminated sites. Farmland makes up the largest share of the total contaminated site area and has the highest per square monetary spillover effects in Taoyuan City; remediation of farmland is one of the most urgent missions for the city. Overall, a NIMBY effect is found to exist for soil-and groundwater-contamination in this city.Keywords: geographic information system, housing property, NIMBY effect, quantile hedonic price model, willingness to pay. JEL classification codes: C21, Q24, Q51, Q53.