The technology of a pre-project comparative assessment of alternative options for locating production facilities, developed by the St. Petersburg ecological project company Eco-Express-Service, is presented. Comparison of options is carried out on the basis of a multi-criteria score-rating assessment in two stages: first, the determination and comparison of values of the environmental safety criteria, then a generalized summary assessment across the totality of the criteria. To bring the obtained results into a general comparative scoring, four competitive methods are used, differing in the degree of detail of the accounting for the indicator significance of the criteria and the ratio of different types of object sites. The stages of technology application are illustrated with concrete examples. The main positive effects and advantages of its use are due to the increased environmental safety of construction and significant (by an order of magnitude) savings of the federal, regional and local budgets and investors owing eliminating unfavorable placement options for the object at the early stages of development.