WAC 246-272A-0110, Table I, Category 2, On-site Sewage Systems
Affected and Interested Parties
Companies that manufacture proprietary treatment products and other interested parties.
What’s Happening?
The Department of Health (Department) adopted a proposed change to WAC 246-272A-0110, Table 1, Category 2, on February 26, 2025. The adopted change adds NSF/ANSI 40 -Residential Wastewater Treatment Systems (versions dated between January 2009 and May 31, 2021) testing for Category 2 products. The rule becomes effective on April 1, 2025.
Why?
Category 2 products treat high-strength sewage from restaurants and other facilities that generate high levels of oil and grease. Prior to the recent rule revision, the rule required testing for Category 2 products under the EPA/NSF Protocol for the Verification of Wastewater Treatment Technologies/EPA Environmental Technology Verification (April 2001). This protocol tested for biochemical oxygen demand (BOD5), total suspended solids (TSS), and oil and grease. EPA archived this testing protocol in 2013. During the recent rule revision of chapter 246-272A WAC, the EPA Method 1664, Revision B (February 2010) testing was adopted for Category 2 systems to treat oil and grease. This recommendation, however, neglected to assure that Category 2 products are also tested for carbonaceous biochemical oxygen should be tested by both EPA Method 1664, Revision B (February 2010) and NSF/ANSI 40 -Residential Wastewater Treatment Systems (versions dated between January demand (CBOD5) and TSS. The Department determined Category 2 products 2009 and May 31, 2021).
Rulemaking Timeline
May 2024 – Start rulemaking
July 2024 – Informal comment period
December 2024 – Formal comment period
December 18, 2024 - Public hearing
March 2025 – Rulemaking complete
Rulemaking Resources
| Documents | What's This | Date Filed/Released |
|---|---|---|
| CR-101 Preproposal Statement of Inquiry (PDF) | Announces intent of rulemaking. | May 13, 2024 |
| CR-102 Proposed Rule (PDF) | Proposed Rulemaking | November 6, 2024 |
| Significant Analysis (PDF) | Describes why the rule is needed | |
| Small Business Economic Impact Statement (PDF) | Describes what a small business is likely to need in order to comply with the proposed rule. | |
| CR-103 Adopted Rule (PDF) | Adopted Rule | February 26, 2025 |
| Concise Explanatory Statement (PDF) | Summary of comments received during formal comment period |
Rule Revision Contacts
Peter Beaton, Rule Coordinator
Jeremy Simmons, Wastewater Section Manager