One of the peculiar properties of phytoremediation is the economic aspect, since it presents costs much lower relative to the other technologies. Black (1995) estimated costs of only 80 $/m3 of soil cleaned with phytoextraction, and 250 $/m3 with soil washing. According to Cunningham and Berti (1997), costs for phytodepuration would be 100000 $/ha, and excavation and landfilling would amount 500000 $/ha, while costs for traditional technologies of in-situ treatment would range between 500000 and 1000000 $/ha. However, actual costs for phytoremediation are still highly variable, and will be better estimated when this innovative technology will be really effective. Presently, indeed, the paucity of full scale application makes difficult to obtain reliable indication on remediation time and costs. A comparison of costs for different remediation technologies is reported in Table 4. It is noteworthy to point out that many ex-situ treatments require the combined use of different items reported in the table, and therefore the whole cost would be higher than the single item.
Table 4 - Comparative costs of different remediation technologies per soil unit