EPA Part 503rule lists four options for meeting pollutant, pathogen, and vector limits in biosolids that are applied to land:
- Exceptional Quality (EQ)
- Pollutant Concentration (PC)
- Cumulative Pollutant Loading rate (CPLR)
- Annual Pollutant Loading Rate (APLR)
Each option is equally protective of the public health and the environment, so EQ, PC, CPLR, and APLR biosolids used in accordance with the Part 503 rule are all equally safe. For a detailed discussion on these four options, the best bet is to refer to the EPA, but the table below gives a brief primer on each.
| Option* | Pollutant Limits | Pathogen Requirements | Vector Attraction Reduction Requirements |
| Exceptional Quality (EQ) Biosolids | Bulk or bagged biosolids meet pollutant concentration limits | Any one of the Class A requirements listed here | Any one of options 1–8 listed here. |
| Pollutant Concentration (PC) Biosolids | Bulk biosolids meet pollutant concentration limits | Any one of the Class B requirements listed here | Any one of the ten options listed here. |
| Any one of the Class A requirements listed here | Option 9 or 10 listed here. | ||
| Cumulative Pollutant Loading rate (CPLR) Biosolids | Bulk biosolids applied subject to cumulative pollutant loading rate limits listed here | Any one of the Class A or Class B requirements listed here | Any one of the ten options listed here. |
| Annual Pollutant Loading Rate (APLR) Biosolids | Bagged biosolids applied subject to annual pollutant loading rate limits | Any one of the Class A requirements listed here | Any one of options 1–8 listed here. |
* Each of these options requires that the biosolids meet ceiling concentrations for pollutants, monitoring requirements, and recordkeeping and reporting requirements. See the EPA’s Part 503 Rule, Chapter 2 [PDF] for more information.
Schwing Bioset’s advanced processing technology can help you understand and meet these requirements. To learn more, contact Schwing Bioset.