Which of the following statements about bioremediation is false?
- bioremediation can be carried out quite effectively in place, avoiding the need to transport contaminated materials elsewhere for treatment
- bioremediation is much less expensive than other methods of hazardous waste site clean up
- bioremediation does not work well in areas where soils have a high day content, making them relatively impermeable
- most projects utilizing bioremediation have involved soil or groundwater contaminated with gasoline or other petrochemicals
- most of the bioremediation projects carried out to date have utilized genetically engineered microbes