Stormwater pollution occurs when rainfall or snowmelt comes in contact with pollutants before running off into storm drains and into the environment. Industrial facilities contain a variety of chemicals and materials that could contaminate stormwater and pollute any runoff that leaves a facility site. Areas of the site where exposed surfaces may contain pollutants are often called “source areas.” Outdoor source areas include:

• Roofs
• Fueling areas
• Vehicle maintenance areas
• Scrap storage areas
• Processing areas
• Waste storage
• Equipment storage
• Chemical storage

Within these source areas, specific pollutants may include:

• Suspended solids, such as dust, compost, garbage, plastic, and debris; Fuels, oils, and greases from vehicles like trucks and forklifts;
• Various chemicals from spills, leaks, or residue left on containers;
• Metals from outdoor maintenance activities or outdoor storage of metal equipment/products; and
• Raw materials.

Frequent inspections of outdoor source areas are important to ensure all stormwater controls are in place to prevent pollution. If asked to perform a stormwater inspection at your site, make sure you use the appropriate site-specific checklist that includes specific source areas and potential pollutants to look out for. In general, there are certain common issues you want to check for. Make sure you don’t see any:

• Leaks from chemical containers or tanks;
• Signs of corrosion or damage on chemical containers;
• Visible sheen or stains on the ground, which are signs of spilled oil or other chemicals; or
• Debris, garbage, or raw materials on the ground that are uncontained and exposed to the weather.

On the other hand, you’ll want to make sure that:

• Secondary containment barriers are in good condition, such as those in hazardous waste storage areas.
• Dumpsters and trash cans are covered or otherwise protected from the weather.
• Nearby spill kits are fully stocked.
• Gutters, drain spouts, storm drains, and catch basins are clear and unclogged.

If any issues are identified during a stormwater inspection, report them to your supervisor immediately. If any source areas around the site need to be cleaned up, clean them up or get help from your coworkers to make sure the issues are fixed before the next rainfall or snowstorm.