GroundRules
40 CFR 143.3: Secondary maximum contaminant levels.
Where this section sits in the code
- Title 40—Protection of Environment
- CHAPTER I—ENVIRONMENTAL PROTECTION AGENCY
- SUBCHAPTER D—WATER PROGRAMS
- PART 143—OTHER SAFE DRINKING WATER ACT REGULATIONS
- Subpart A—National Secondary Drinking Water Regulations
The secondary maximum contaminant levels for public water systems are as follows:
Contaminant Level
Aluminum 0.05 to 0.2 mg/l.
Chloride 250 mg/l.
Color 15 color units.
Copper 1.0 mg/l.
Corrosivity Non-corrosive.
Fluoride 2.0 mg/l.
Foaming agents 0.5 mg/l.
Iron 0.3 mg/l.
Manganese 0.05 mg/l.
Odor 3 threshold odor number.
pH 6.5-8.5.
Silver 0.1 mg/l.
Sulfate 250 mg/l.
Total dissolved solids (TDS) 500 mg/l.
Zinc 5 mg/l.
These levels represent reasonable goals for drinking water quality. The States may establish higher or lower levels which may be appropriate dependent upon local conditions such as unavailability of alternate source waters or other compelling factors, provided that public health and welfare are not adversely affected.
Collected 2026-08-27T02:26:04Z. Source file · JSON