Soil Remediation: BioRem-2000 Surface Cleanerâ„¢ can be applied to topical spills of hydrocarbons on soil and gravel areas. It can be applied by spraying directly onto the surface of the soil or gravel. Tilling the soil and re-spraying provides an even distribution of microbes throughout the soil, as well as providing aeration (oxygen) for the microbes. Repeated tilling accelerates the biological degradation of the soil contaminants.