Which substance is typically reduced in concentration by installation of a grease interceptor?

The installation of a grease interceptor is primarily designed to capture and reduce the concentration of grease and fats in wastewater before it enters the treatment system or sewer. Grease interceptors function by allowing wastewater to flow through a chamber where fats, oils, and grease (often referred to collectively as FOG) rise to the surface and are retained, preventing them from causing blockages in pipes and treatment systems.

By specifically targeting the removal of grease and fats, grease interceptors help maintain the effectiveness of wastewater treatment processes and protect infrastructure from damage. This focus on reducing grease content is critical because excessive grease can lead to sanitary sewer overflows and increase the risk of downstream treatment challenges. Other substances like organic solids, nutrients, and metals may be managed by different systems or processes and are not the primary focus of grease interceptors. Thus, choice B accurately reflects the substance that is most significantly reduced by the installation of a grease interceptor.