The town of Puerto Montt was founded in 1853 as an access road to the region of Lake Llanquihue and, from that moment on, its progress and growth was rapid. If the 1895 census counted almost 4,700 inhabitants, by 1907 the population had almost doubled (7,364). Although the city was maintained mainly thanks to its contact with the sea, the arrival of the railroad (1912), which allowed the connection with the central zone of the country, brought with it a new expansion and by 1950 the city had 27,500 inhabitants. During the 1970s, the population continued to grow at a rapid pace, mainly due to rural-urban migration, reaching 90,000 inhabitants. By 1979 Puerto Montt was nominated as the capital of the Lakes Region, becoming the administrative center of the central-south zone. Thus, industries are forced to leave the now downtown area. The fuel plant in Puerto Montt for the storage and distribution of fuels and liquids was in operation from 1960 to 2005. In July 2007, work began on the extraction of the buried facilities, initiating a soil remediation process using the . The project “Rehabilitation of former ESSO Puerto Montt Plant Land for Future Uses” was favorably qualified by means of Exempt Resolution No. 362/2007 of the Regional Environmental Commission of the Los Lagos Region and was carried out in the Chinquihue Sector of Puerto Montt. The treatment of the contaminated soil was carried out using the bioremediation technique: The total volume of excavated soil corresponded to approximately 5,270 m, which was distributed in 12 biopiles. This treatment was carried out with great success since . The time required for the compounds of concern to reach concentrations below the risk-based concentration target values (ROCVs) was between 45 and 59 days for the cleaner soils and 113 days for the soils with higher concentrations. Another success factor of the project is that the cleanup work was carried out in close proximity to populated areas (about 50 m away). The following table shows the final concentrations for each of the biopiles used for soil treatment. As can be seen, the concentrations of the compounds of concern decreased significantly: Once the remediation process was completed, the Ex ESSO Puerto Montt Plant site was returned to Bienes Nacionales.
