Construction SWPPP in an Industrial Environment

Industrial facilities are required to obtain coverage under the Multisector General Permit (EPA) or in CA under the Industrial General Permit for storm water discharges. These Permits cover the operations of the facilities year after year. When an industrial covered facility undergoes a construction project within their drainage areas covered by the Industrial Permit those construction activities can cause unintended water quality exceedances that are not associated with their normal operations. How this interplay can impact compliance requirements will be investigated using the California General Permits as a backdrop for the regulatory environment. Example facilities will include airports, and large manufacturing sites.
Construction related activities and materials may have more total suspended solids and sediment that would not normally be present during typical facility operations. When these pollutants are added to the current storm water discharge, the Numeric Action Levels may be exceeded under the Industrial General Permit but the discharges from the Risk Level 1 construction site were not sampled as that is not required under the Construction General Permit. This scenario could cause the industrial compliance group to have to prepare Level 1 Exceedance Response Evaluation and a Level 1 Exceedance Response Action Report and be held as a Level 1 facility until the average of 4 consecutive storms are sampled to be below the NAL. This is typically at least one year of sampling. This construction related exposure now puts the industrial facility on the regulatory map to the regulators and the third party NGOs. So in essence, a couple months of construction can lead to a year or more of additional reporting and compliance scrutiny. This presentation will provide some strategies to identify and mitigate these types of issues when one Permit overlaps another Permit.