2C, Storm Water Ponds Maintenance Program

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For example, in the Great Lakes Basin, especially in the large tributaries and harbors, a more extensive list of parameters is required to properly characterize sediment. It is known that many of these tributaries have concentrations of polycyclic aromatic hydrocarbons (PAIL) from former coal gasification plants, urban run- off, oil spills, and vehicle and smoke stack particulate emissions that are deposited on the watershed. For projects involving sediment in urban areas associated with inland waters and Great Lakes tributaries, PAH analysis is required. Two contaminants that bioconcentrate up aquatic food chains are highly bioaccumulative in upper trophic level organisms like game fish are PCBs (polychlorinated biphenyls) and mercury. In the risk assessment phase, fish consumption advisories issued by the MDNR should be reviewed to determine if the project area is in a water body included in the advisory. For projects involving sediment from water bodies included in a fish and/or wildlife consumption advisory, mercury and PCB analysis, as relevant, is required. Stormwater projects Stormwater project proposers should also review the "Modified Characterization and Permit Approach for Urban Stormwater Ponds" section below. Management levels Based on the results of completed sediment characterization, that is, the type and level of pollutants in the material in comparison to established SRVs, dredged material is categorized into one or more Management Levels. The Management Level of a dredged material dictates the appropriate disposition of the material. Dredged Material is categorized into three Management Levels: Level 1 Level 2 Level 3 Level 1 Dredged Material is suitable for use or reuse on properties with a residential or recreational use category. Level I Dredged Material is characterized as being at or below analyte concentrations for all of the SRVs listed in the Level 1 SRV column of Table 5. The SRVs incorporate the most common human exposure pathways (ingestion, dermal contact, and inhalation of contaminants volatilized from soil in outdoor air) using generic exposure assumptions. The Level 1 SRVs generally use a chronic residential exposure scenario, but are also protective of acute health effects in young children when acute toxicological data is available. For dredged materials, the Level 1 SRV limits in Table 5 are the most restrictive. Note: Exposure pathways in an agricultural land use setting have not been evaluated, and is therefore not an appropriate land use category for comparison to SRVs. Level 2 .dredged Material is suitable for use or reuse on properties with an industrial use category. Level 2 Dredged Material is characterized as being at or below analyte concentrations for all of the SRVs listed in the Level 2 SRV column of Table 5. The Level 2 SRVs use an industrial exposure scenario based on average working adults according to a typical industrial site use. Level 2 SRVs are less restrictive then the Level 1 SRVs. Level 3 Dredged Material is characterized as having significant contamination, as demonstrated by one or more analyte concentrations being greater than the Level 2 SRV column of Table 5. Sites that have potentially important exposure pathways or other conditions that are not incorporated into a residential or industrial risk characterization must be evaluated in the context of a fully site specific risk assessment for which site specific SRVs are calculated that account for all potentially significant exposure Managing Dredged Materials in the State of Minnesota June 2009 15 Dredged material is categorized into management levels, based on the level of contamination, Minnesota Pollution Control Agency Analysis of parameters beyond the baseline analytes may be indicated based on the evaluation of historical land uses and the reasonable likelihood for pollutants in sediment to be dredged.