9.3 Lead & Copper Rule Revisions (LCRR)

9.3 Lead & Copper Rule Revisions (LCRR)

Quick Answer: The Lead and Copper Rule (LCR) is a treatment-technique rule — there is no MCL for lead at the tap. Instead, systems sample at high-risk customer taps (Tier 1 sites) and judge compliance by the 90th-percentile value: lead action level = 0.015 mg/L (15 ppb), copper action level = 1.3 mg/L. The Lead and Copper Rule Revisions (LCRR), with compliance beginning January 2022, added a lead service line (LSL) inventory (due October 2024) and faster LSL replacement. EPA's Lead and Copper Rule Improvements (LCRI) is in development and may lower the lead action level to 10 ppb; LCRR is the current operative rule.

Why a Treatment Technique Instead of an MCL

Lead in drinking water rarely comes from the source or the treatment plant — it comes from materials in the plumbing and service line: lead service lines, lead solder, brass fittings, and galvanized pipe attached to a lead service line. Because the same water can be safe at the plant and unsafe at the tap, EPA regulates lead and copper with a treatment technique: corrosion-control treatment that keeps water non-aggressive, plus tap sampling at the highest-risk sites.

Action Levels and the 90th Percentile

The action levels are not MCLs — they are thresholds that trigger additional treatment and actions:

The 90th percentile is calculated by ranking results from lowest to highest and picking the value at the 90th-percentile position. If a system samples 10 sites, the 9th-highest value is the 90th-percentile result. If that value exceeds the action level, the system has an action-level exceedance — not an MCL violation.

Tier 1 Sampling Sites

Samples must come from the highest-risk taps. Tier 1 sites are, in priority order:

1. Lead service lines (LSLs) — single-family residences with a known or presumed lead service line.
2. Lead-soldered copper plumbing installed after 1982 — the high-risk lead-solder window that ended when the 1988 federal lead-solder ban took effect (mandated by the 1986 SDWA Amendments).
3. If insufficient Tier 1 sites exist, the system drops to Tier 2 (multi-family with LSLs or lead solder) or Tier 3 (single-family with copper pipe and lead-solder sites of any age).

This is why the post-1982 window matters: the LCR defines lead-soldered copper installed after 1982 as high-risk.

Sampling Protocol — First-Draw, 1 Liter, 6-Hour Stagnation

Each tap sample is a first-draw 1-liter sample collected after the water has stood in the plumbing for at least 6 hours (overnight is typical). The tap is not flushed before sampling. The sample represents what a customer would drink first thing in the morning after stagnation — the worst-case exposure for lead leaching.

Key protocol points:

• Use a cold-water kitchen or bathroom tap used for consumption.
• Do not remove or clean the aerator before sampling unless the system's protocol requires it.
• Do not sample through a point-of-use filter.
• Sample bottles contain nitric acid preservative.
• Record the stagnation time on the chain-of-custody.

This is the opposite of coliform sampling, where you flush the tap first.

What an Action-Level Exceedance Triggers

If the 90th-percentile lead value exceeds 0.015 mg/L (or copper exceeds 1.3 mg/L), the system must:

1. Optimize corrosion-control treatment (or install it if none exists) — typically by adjusting pH and alkalinity or adding an orthophosphate inhibitor.
2. Conduct source-water monitoring for lead and copper at the entry point to the distribution system.
3. Begin or accelerate lead service line replacement at a rate of 7% per year under the original LCR; LCRR tightens this.
4. Deliver public education to consumers about lead sources, health effects, and tap-flushing.

Public education for lead is delivered annually until the system returns below the action level for two consecutive 6-month periods.

LCRR and LCRI Status (2026)

• LCRR (compliance January 2022) — the current operative rule. It requires systems to inventory lead service lines (initial inventory due October 16, 2024), notify customers served by LSLs, and replace LSLs faster when action levels are exceeded.
• LCRI (Lead and Copper Rule Improvements) — under development by EPA. Proposals include lowering the lead action level to 10 ppb, requiring LSL replacement on a firmer schedule, and strengthening public education. Treat the LCRR requirements as the operative rule on the exam unless a question explicitly asks about pending proposals.

Distribution Operator Role

• Help select and maintain Tier 1 sampling sites and update the site inventory.
• Deliver sample bottles to residents and explain the first-draw, 6-hour stagnation protocol.
• Collect the bottles, complete the chain-of-custody, and ship to the lab within holding times.
• Track results and flag a 90th-percentile exceedance to the state and the public education lead.
• Maintain the LSL inventory records for your system.

Exam Tip

Three numbers and one protocol dominate LCR questions: 0.015 mg/L lead, 1.3 mg/L copper, 6-hour first-draw. Remember the action level is mg/L (15 ppb is the same as 0.015 mg/L). And remember: an exceedance is not an MCL violation — it triggers treatment, monitoring, and education.