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The United States Environmental Protection Agency (“EPA”) published the 9th Biennial Report titled:

Biosolids Biennial Report No. 9 (“Report No. 9”)

Biennial reports are required by federal legislation found in Section 405(d)(2)(C) of the Clean Water Act. Addressed in Report No. 9 are the sewage sludge regulations found at 40 CFR Part 503. The reporting period is 2020-2021.

Biosolids typically refer to sewage sludge treated to meet the requirements found in 40 CFR Part 503. This is material intended to be applied to land as a soil amendment or fertilizer.

Section 405(d) requires EPA to establish requirements and management practices for the use and disposal of sewage sludge (i.e., biosolids). The regulations promulgated in 40 CFR Part 503 implement this mandate.

Section 405 of the Clean Water Act also requires EPA to biennially:

• Identify those toxic pollutants which, on the basis of available information on their toxicity, persistence, concentration, mobility or potential for exposure, may be present in sewage sludge in concentrations which may adversely affect public health or the environment, and propose regulations specifying acceptable management practices for sewage sludge containing each such toxic pollutant and establishing numerical limitations for each such pollutant.
• From time to time, but not less often than every two years, review the regulations for the purpose of identifying additional toxic pollutants.

Note that a biennial report does not result in the addition of regulated pollutants in sewage sludge under 40 CFR Part 503. EPA states that it simply assists in meeting the Clean Water Act requirements to identify additional pollutants in biosolids and compile data that may be used to assess risk.

EPA states in Report No. 9 that since the previous report was published the federal agency:

. . . undertook an effort to curate a complete list of chemicals found in biosolids based on the three previous national sewage sludge surveys and eight biennial review reports.

Through curation it was determined there were 259 chemicals that had been previously reported as detected in biosolids but had not been included in the data collection phase of previous biennial reviews. The agency also made corrections to the Chemical Abstracts Service of 22 chemicals that had been reported in previous biennial reviews. These 281 chemicals are included in the biennial review process for Report No. 9.

Report No. 9 also identifies what it describes as “16 new articles” that provide relevant data on chemical pollutants found in biosolids along with two papers which provide data on both chemical and microbial pollutants. Thirteen new chemicals are stated to have been found in biosolids which include:

• Nine drugs
• Three per- and polyfluoroalkyl substances
• One element

New data is stated to have been identified for three chemicals. Further, concentration data in biosolids were found for the 13 new chemicals.

Human health toxicity values were stated to have been found for 70 chemicals and 64 previously identified chemicals. In addition, five of the new articles are stated to have provided relevant data for microbial pollutants that had been found in biosolids. This review is stated to have identified one new microbial pollutant in biosolids and data for two previously identified microbial pollutants.

A copy of Report No. 9 can be downloaded here.