By Amanda Czepiel, J.D., BLR Water Expert
aczepiel@blr.com
Iindustrial stormwater permits have a visual assessment requirement. Under EPA’s MSGP 2008, all permittees are required to perform quarterly visual assessments of each outfall once each quarter for the entire permit term., with exceptions only for adverse weather conditions, climates with irregular stormwater runoff, areas subject to snow, inactive or unstaffed sites, and substantially identical outfalls. To comply with visual assessment requirements, collect samples in clean, clear glass or plastic containers and assess the color, odor, clarity, floating solids, settled solids, suspended solids, oil sheen, and foam.
Other types of required monitoring may include benchmark monitoring, effluent limitation guidelines monitoring, state- or tribal-specific monitoring, or impaired waters monitoring – check your permit to see if any additional monitoring applies to your facility.
Where are the discharge points?
Walk the grounds and perimeter of your facility during a storm event to identify the locations of outfalls (where stormwater exits the facility property, including pipes, ditches, swales, and other structures that transport stormwater). Also determine whether stormwater runoff is entering the facility from a neighboring property.
Where and how should you sample?
Typical sampling points include the underground pipes that collect stormwater and convey it to an off-site location, open ditches, gutters, or swales, facility driveways, and outlets discharging off-site from on-site detention ponds. Sample stormwater before it leaves the facility and downstream from all other industrial materials and activities.
Some permits, such as the MSGP 2008, may allow you to reduce the number of outfalls you sample if you can determine that some outfalls are “substantially identical,” meaning that they have similar industrial activities and control measures, exposed materials, and runoff coefficients.
Who will sample and what laboratory will analyze the results?
Your Stormwater Pollution Prevention Plan (SWPPP) should identify the monitoring team. The monitoring team members should be staff familiar with the SWPPP, the layout of the facility, potential pollutant sources, and the monitoring and reporting program. Ideally, the team consists of at least one individual from each shift so that a team member is always present during operating hours.
You must also select a lab to analyze the samples and that can provide such components as assistance, sampling bottles, and forms. EPA recommends selecting a lab that is a participant in EPA’s Discharge Monitoring Report – Quality Assurance (DMRQA) Program. During the lab selection process, discuss with laboratory representatives the types and sizes of sampling bottles, how to fill the bottles, required labels and forms, sample preservation methods and holding times, how to deliver the sample to the lab, and the applicable costs. Review "How to Hire an Environmental Testing Laboratory" for more guidance on selecting a lab that fits your needs.
What materials do you need?
Use a checklist to make sure you have all of your necessary supplies in order. Have materials readily available for a storm event: sample bottles, forms and field notebook, coolers and/or ice, and rain gear.
You’re ready to sample!
If you have answered the above questions, you should be adequately prepared to comply with your industrial stormwater permit’s sampling requirements. For more tips and guidance for industrial stormwater sampling, see EPA’s Industrial Stormwater Monitoring and Sampling Guide.
Amanda Czepiel, J.D., is a Legal Editor for BLR’s environmental law publications. Ms. Czepiel has over 6 years of experience as an attorney and writer in the field of environmental compliance resources and has published numerous articles on a variety of environmental law topics, including wastewater and NPDES permitting, brownfields and contaminated sites remediation, oil spill prevention, wetlands, and corporate sustainability. Before starting her career in publishing, Ms. Czepiel worked in hospitality consulting and for various non-profit organizations and government agencies in the environmental field. Ms. Czepiel received her law degree from the University of Connecticut School of Law, and is licensed to practice in the state of Connecticut.