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Site Remediation–Related Laws and Regulations
Published in Rong Yue, Fundamentals of Environmental Site Assessment and Remediation, 2018
Ning-Wu Chang, Jian Peng, Jason J. Wen, Yue Rong
A TMDL is the maximum amount of a pollutant that a water body can receive and still safely meet WQSs. Each TMDL must account for all sources of the pollutant, including point source WLA, nonpoint source and natural background load allocation (LA), and a margin of safety (MOS): TMDL = LA + WLA + MOS. TMDLs allocate allowable pollutant loads for each source and identify management measures that, when implemented, will assure that WQSs are attained. Currently, there are nearly 2000 water body–pollutant combinations and over 400 TMDL projects in California. TMDLs are essentially technical documents and are not by themselves enforceable. Once formally adopted, the WLAs will be written into appropriate permits (e.g., NPDES permits, as discussed later, or other permits, such as waste discharge requirements [WDRs]) to be implemented. For groundwater and soil remediation projects that could discharge point source pollutants (including sediments) to surface waters, such as groundwater pump and treat, the allocation will be written into such permits. Meeting the permit requirements often becomes an important part of the cleanup projects themselves, since they are often fairly stringent.
Water Quality and Security
Published in Barry L. Johnson, Maureen Y. Lichtveld, Environmental Policy and Public Health, 2017
Barry L. Johnson, Maureen Y. Lichtveld
A TMDL is both a planning process for attaining water quality standards and a quantitative assessment of problems, pollution sources, and pollutant reductions needed to restore and protect a river, stream, or lake. TMDLs may address all pollution sources, including point sources such as municipal sewage or industrial plant discharges; nonpoint sources, such as runoff from roads, farm fields, and forests; and naturally occurring sources, such as runoff from undisturbed lands. The TMDL itself does not establish new regulatory controls on sources of pollution. However, when TMDLs are established, municipal and industrial wastewater treatment plants may be required to install new pollution control technology.
Ambient Water-Quality Monitoring in the Willamette River Basin
Published in Antonius Laenen, David A. Dunnette, River Quality, 2018
A TMDL is the total amount of a pollutant that can enter a water body without causing it to violate a water-quality standard for that pollutant. Once a TMDL is established, the “load" is divided into load allocations (that part of the load that is either from natural background sources or point sources) and waste load allocations (that part of the load that is allocated to point sources of pollution).
Importance of accurately quantifying internal loading in developing phosphorus reduction strategies for a chain of shallow lakes
Published in Lake and Reservoir Management, 2020
Dale M. Robertson, Matthew W. Diebel
Water quality in many lakes has declined because of excessive external nutrient loading from their watersheds (for most lakes this refers to phosphorus [P]; Schindler et al. 2016), and total maximum daily loads (TMDLs) are being developed. A TMDL is a regulatory term describing a plan for restoring impaired waters that identifies the maximum amount of a pollutant a waterbody can receive while still meeting a specified water quality standard (US Environmental Protection Agency [USEPA] 2019). To estimate the P load reductions needed to meet the specified standard, eutrophication models, which estimate inlake total phosphorus concentrations (TP) from external P loading and lake morphometry, are frequently used (USEPA 2019). Most of these models originated from basic Vollenweider (1975) type models and are summarized in Cooke et al. (1993).
Limnology and the future of African inland waters
Published in Inland Waters, 2018
Richard D. Robarts, Tamar Zohary
Harding (2017) has argued that South Africa needs to move to a total mean daily load (TMDL) approach to managing its water resources, an approach that has been successfully tested in South Africa in 2 catchments. TMDL accounts for all point and nonpoint sources of a particular pollutant within a catchment upstream of a particular impoundment, river segment, or wetland, so it is both a quantitative assessment and a planning process (Harding 2017). Some of the other benefits of the approach include science comprehensively informing the law, serving as both an opportunity and a template of needs for immediate upskilling that could become the foundation of future reservoir management in South Africa (Harding 2017).
Grey water footprint as a tool for wastewater treatment plant assessment– Hostivice case study
Published in Urban Water Journal, 2021
Lada Stejskalová, Libor Ansorge, Jiří Kučera, Dagmar Vološinová
The concept of the Critical Load (Lcrit) is similar to the Total Maximum Daily Load (TMDL) developed by the US Environmental Protection Agency (Benham and Zeckoski 2007). The TMDL calculates the maximum amount of a pollutant allowed to enter a water body so that the water body will meet and continue to meet water quality standards for that particular pollutant.