Statement From Source Document Poa
• On October 31st, the City submitted a monitoring plan to the EPA. The monitoring requirements include the following:
1. Monitoring beginning on June 1, 2022, to establish a baseline for CSO solids loading and solids contaminant levels;
2. Periodic in-Canal monitoring beginning one year after capping is completed in RTA 1.
To meet the above requirements, the monitoring plan will quantify the levels of contaminants of potential concern (COPCs) on solids discharging from CSO outfalls RH-034 and OH-007 along with the levels of total suspended solids (TSS), suspended solids organic carbon, and suspended solids grain size distribution. Samples will be collected from sewer pipes feeding these two outfalls quarterly for a period of two years starting from June 1, 2022. This sampling will provide a baseline for the characteristic of the CSO solids that enter the Canal. To quantify the solids loading to the Canal, the City will use data from this monitoring program along with the Owls Head and Red Hook WWTP Collection System. The flow estimated from a model and the measured TSS concentrations will be used by the City to estimate the annual CSO solids load to the Canal.
The monitoring plan described above, as well as DEP’s regular harbor water quality monitoring program are the best methods for understanding the water quality impacts of combined sewer overflows on the Gowanus Canal. The annual report is available at DEP’s website and will contain information about major indicators of environmental changes including dissolved oxygen, bacteria, secchi transparency, chlorophyll ‘a’ and nitrogen levels.
Narrative
The City has submitted an update to the Combined Sewer Overflow (CSO) monitoring workplan and responded to two rounds of the United States Environmental Protection Agency (USEPA) comments. The City is targeting Fall of 2022 to begin the monitoring program, as required. It is anticipated that several rounds of sampling will be completed by the end of 2022.
