40 CFR § 142.301 - What is a small system variance?

---
identifier: "/us/cfr/t40/s142.301"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "40 CFR § 142.301 - What is a small system variance?"
title_number: 40
title_name: "Protection of Environment"
section_number: "142.301"
section_name: "What is a small system variance?"
chapter_name: "ENVIRONMENTAL PROTECTION AGENCY"
subchapter_number: "D"
subchapter_name: "WATER PROGRAMS"
part_number: "142"
part_name: "NATIONAL PRIMARY DRINKING WATER REGULATIONS IMPLEMENTATION"
positive_law: false
currency: "2026-03-24"
last_updated: "2026-03-24"
format_version: "1.1.0"
generator: "[email protected]"
authority: "42 U.S.C. 300f, 300g-1, 300g-2, 300g-3, 300g-4, 300g-5, 300g-6, 300j-4, 300j-9, and 300j-11."
regulatory_source: "41 FR 2918, Jan. 20, 1976, unless otherwise noted."
cfr_part: "142"
---


# 142.301 What is a small system variance?

Section 1415(e) of the Act authorizes the issuance of variances from the requirement to comply with a maximum contaminant level or treatment technique to systems serving fewer than 10,000 persons. The purpose of this subpart is to provide the procedures and criteria for obtaining these variances. The regulations in this subpart shall take effect on September 14, 1998.