Drinking water rules
What an MCL is
An MCL is a Maximum Contaminant Level. It is the legal limit for a contaminant in drinking water under 40 CFR Part 141. It is not a treatment technique and not an action level.
Short definition only
MCL, treatment technique, and action level are three different kinds of duty. The comparison stays on the blog: MCL vs treatment technique vs action level.
Related source: 40 CFR Part 141.
The $199 Complete System Report is the cited document. Orevant Pro is $87/month or $870/year.
Orevant is not legal advice and does not report your system to the state.
FAQ
Is every limit an MCL?
No. Some rules use a treatment technique or an action level instead.
Where do I start?
Check my system with your PWSID.