Domestic wastewater which passes through a sewer system to a POTW is not considered to be a ______.

Domestic wastewater that travels through a sewer system to a Publicly Owned Treatment Works (POTW) is not classified as solid waste or hazardous waste. The primary characteristic of domestic wastewater is that it primarily consists of water and typical household pollutants, such as food scraps, human waste, soaps, and detergents.

Solid waste refers to discarded materials that are not liquid or gaseous, including a variety of refuse and garbage from homes and industries. Since domestic wastewater is liquid, it does not fall under the category of solid waste.

Hazardous waste, on the other hand, is defined by specific criteria relating to its composition, toxicity, or potential harm to human health or the environment. Domestic wastewater generally does not meet these criteria, as it is treated to minimize pollutants before discharge. Therefore, it is classified separately and does not fall into the hazardous waste category unless it contains specific hazardous materials in significant amounts.

As a result, domestic wastewater is distinct from both solid waste and hazardous waste, which justifies the selection of the answer indicating that it does not belong to either category.