10 CFR § 39.51 - Use of a sealed source in a well without a surface casing.

---
identifier: "/us/cfr/t10/s39.51"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "10 CFR § 39.51 - Use of a sealed source in a well without a surface casing."
title_number: 10
title_name: "Energy"
section_number: "39.51"
section_name: "Use of a sealed source in a well without a surface casing."
chapter_name: "NUCLEAR REGULATORY COMMISSION"
part_number: "39"
part_name: "LICENSES AND RADIATION SAFETY REQUIREMENTS FOR WELL LOGGING"
positive_law: false
currency: "2026-03-24"
last_updated: "2026-03-24"
format_version: "1.1.0"
generator: "[email protected]"
authority: "Atomic Energy Act of 1954, secs. 53, 57, 62, 63, 65, 69, 81, 161, 181, 182, 183, 223, 234 (42 U.S.C. 2073, 2077, 2092, 2093, 2095, 2099, 2111, 2112, 2201, 2232, 2233, 2273, 2282); Energy Reorganization Act of 1974, secs. 201, 206 (42 U.S.C. 5841, 5846); 44 U.S.C. 3504 note."
regulatory_source: "52 FR 8234, Mar. 17, 1987, unless otherwise noted."
cfr_part: "39"
---


# 39.51 Use of a sealed source in a well without a surface casing.

The licensee may use a sealed source in a well without a surface casing for protecting fresh water aquifers only if the licensee follows a procedure for reducing the probability of the source becoming lodged in the well. The procedure must be approved by the Commission pursuant to § 39.13(c) or by an Agreement State.