Which of the following is a type of control that must be in place according to the SWPPP?

The correct answer is structural controls, as these are essential components outlined in a Storm Water Pollution Prevention Plan (SWPPP). Structural controls are designed to manage storm water runoff and reduce contamination from industrial activities. These control measures may include features such as retention ponds, swales, biofilters, permeable pavements, and other physical installations that help treat or contain storm water before it can discharge into nearby water bodies.

Implementing structural controls is crucial because they provide a tangible means to prevent pollutants from industrial sites from entering the environment. They are often engineered solutions tailored to fit the specific circumstances of a facility, and they work in tandem with other practices to ensure compliance with regulatory standards.

The other options—financial controls, human resource controls, and marketing controls—do not fall under the scope of the SWPPP. These types of controls focus on aspects like budgeting, employee management, or market strategies, which do not directly pertain to storm water management or pollution prevention in an industrial context. Therefore, they do not meet the requirements set forth by the SWPPP guidelines.