What types of industrial discharges can lead to sewer plugging?

The correct choice highlights the impact of fibrous materials and grease on sewer systems. Fibrous materials, such as those found in paper products, food waste, and similar items, can accumulate in pipes and create blockages. These materials do not break down easily when disposed of in the sewer system, leading to significant clogs, especially when combined with other waste.

Grease is another critical factor in sewer plugging. When fats, oils, and grease cool and solidify within the sewer lines, they can stick to the walls of the pipes and trap other materials, further exacerbating the blockage issue. The combination of fibrous materials and grease creates a dense, obstructive mass that can restrict flow and lead to backups or overflows in the sewer system.

Understanding the effects of these materials can help in preventing sewer issues by promoting proper disposal practices within industrial processes, thereby protecting the infrastructure of wastewater systems.