Sanitary sewer & special pathways
Most Ac-225 waste should not go to the sanitary sewer. The §20.2003 release pathway exists, but the per-isotope monthly average concentration limits, the requirement for the material to be readily soluble or dispersible in water, and the recordkeeping burden combine to make decay-in-storage the better default for almost every program.
Sanitary-sewer release: when and how
Eligibility
Material must be readily soluble or dispersible in water and meet the §20.2003 concentration limits averaged over a month. Patient-excreta release from a sanitary toilet is treated separately from facility liquid waste release.
Recordkeeping
Document activity per release, monthly running total, and basis for the concentration calculation. Inspectors will ask for the monthly average — not just the per-release record.
Patient excreta
Patient-restroom releases via sanitary plumbing are permitted and standard. Document the post-administration hold protocol and the rationale for any caregiver instructions provided at discharge.
Off-site shipment
If any stream must leave the site as licensed waste — typically high-activity sharps from a clinical-trial dose-draw — coordinate manifest, transport, and broker acceptance in advance under §20.2006.
Defaulting to decay-in-storage for anything that fits — and reserving §20.2003 for genuinely liquid streams where decay storage isn't practical — tends to work well. Programs that try to optimize sanitary-sewer release often end up with more recordkeeping burden than storage space saved.
- 10 CFR §20.2003 — Disposal by release into sanitary sewerage.
- 10 CFR §20.2006 — Transfer for disposal and manifests.