Technical Users Background Document

On this page:

• Technical Users Background Document and Appendices
• Addendum
  • Radioactive Pollutant Categories
  • Color Pollutant Category
  • Whole Effluent Toxicity (WET) Pollutant Category
  • PFAS Pollutant Category

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 Technical Users Background Document and Appendices

Technical Users Background Document for the Water Pollutant Loading Tool (PDF) (143 pp, 2.4 MB)

• Section 3.2.3 - Nutrient Aggregation
• Appendix A (PDF) (234 pp, 1 MB)
• Appendix B (PDF) (211 pp, 1.2 MB)
• Appendix C (PDF) (58 pp, 348 K)
• Appendix D (PDF) (1,064 pp, 4.15 MB)
• Appendix E (PDF) (18 pp, 99K)

Addendum to Section 3.3.1

 3.3.1.10 Radioactive Pollutant Categories in Water Pollution Search

The Loading Tool calculates annual pollutant loadings for specific radioactive isotopes or radionuclides, as listed in Table 3-20. Radionuclides can be measured in units of mass or radioactivity (in curies (Ci)). For all measurements, the Loading Tool first converts to standard units, either Ci or grams. For measurements of radioactivity, the specific activity of the radionuclide is used to convert from curies to mass.

Source: Turner, James E. (1992). Atoms, Radiation, and Radiation Protection. Mc-Graw Hill.

^aSource: International Atomic Energy Agency (IAEA) International Nuclear Structure and Decay Data Network. Evaluated Nuclear Structure Data File (ENSDF) DatabaseExit
^bRadioactivity (Ci/d)/[SA (Ci/g)*(1000 g/kg)] = Mass (kg/d)
^cRadioactivity (Ci/L)*(1000 mg/g)/(SA (Ci/g)) = Concentration (mg/L)

Parameters included in the Radionuclides Category. All parameters measuring radioactivity of a specific radionuclide are included in this category.

Parameter Grouping/Category Priorities. All parameters with the same pollutant name are grouped together as shown in the "Group Priority" column of Table 3-20. The radionuclide category does not have a category-level aggregation hierarchy and includes all radionuclides with equal priority. Therefore the category priorities for all radionuclide parameter codes are assigned a '1' in Table 3-20.

Pollutant Load Aggregation. For category aggregation, all pollutant loads are summed together to calculate the total load.

Table 3-21 below provides the pollutant group and category priority for all parameters in the General Radioactivity category.

Parameters included in the General Radioactivity Category. All parameters measuring gross radioactivity or radioactivity of more than one radionuclide are included in this category. Pollutant loadings are not calculated for these parameters.

Parameter Grouping/Category Priorities. All parameters with the same pollutant name are grouped together as shown in the "Group Priority" column of Table 3-21. The general radioactivity category does not have a category-level aggregation hierarchy and includes all radioactive pollutants with equal priority. Therefore the category priorities for all general radioactivity parameters are assigned a '1' in Table 3-21.

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 3.3.1.11 Color Pollutant Category in Water Pollution Search

The Loading Tool provides data for measurements of color in wastewater. Color measurements may be reported using a variety of units, such as Platinum Cobalt (Pt-Co) units or pound/ton produced. The Loading Tool presents the measurements in the units reported on DMRs, and does not convert the measurements into standard units.

Parameters Included in the Color Category. All parameters measuring color are included in this category. A complete list of the color parameters is provided in Table 3-22 below.

Parameter Grouping/Category Priorities. There is no grouping or prioritization in the color pollutant category.

Pollutant Load Aggregation. There is no load aggregation in the color pollutant category.

 3.3.1.12 Whole Effluent Toxicity (WET) Pollutant Category in Water Pollutant Search

The Loading Tool provides data for wastewater parameters measuring WET. WET refers to the aggregate toxic effect to aquatic organisms from all pollutants contained in a facility’s wastewater. WET tests measure a wastewater's effects on specific test organisms' ability to survive, grow and reproduce. WET measurements may be reported using a variety of units, such as percentages or pass/fail. The Loading Tool presents the measurements in the units reported on DMRs, and does not convert the measurements into standard units.

See Whole Effluent Toxicity Methods for more information about Clean Water Act WET test methods.

Parameters Included in the WET Category. All parameters measuring WET are included in this category. A complete list of the WET parameters is provided in the DMR Pollutant Parameters Used and Not Used by the Loading Tool (CSV) (650 K).

Parameter Grouping/Category Priorities. There is no grouping or prioritization in the WET pollutant category.

Pollutant Load Aggregation. There is no aggregation in the WET pollutant category.

 3.3.1.13 PFAS Pollutant Category in Water Pollution Search

The Loading Tool provides data for measurements of  Per- and Polyfluoroalkyl Substances (PFAS) in wastewater. PFAS are a group of man-made chemicals that includes PFOA, PFOS, GenX, and many other chemicals. The Loading Tool calculates pollutant loadings for individual pollutants within this category.

Parameters Included in the PFAS Category. The list of parameters is provided in Table 3-23 below.

Parameter Grouping/Category Priorities. There is no grouping or prioritization in the PFAS pollutant category.

Pollutant Load Aggregation. There is no load aggregation in the PFAS pollutant category.