Benzene in Well Water: The Public 0.005 mg/L Line

By SubcontractorHub Editorial Team·Published October 2026

Dealers meet benzene in well water on a lab sheet that also lists other solvents, or on a city report a customer brings to the kitchen table. The annual city packet is a consumer confidence report. This page is only the benzene row. The national primary rules apply to public water systems. They are not a private-well statute. How to order the jug is the well water testing guide.

Benzene in Well Water on the Primary Table

The national primary drinking water regulations are legally enforceable primary standards and treatment techniques that apply to public water systems. In the organic block, benzene's MCLG cell is zero. The MCL is 0.005. The potential health effects listed are anemia, a decrease in blood platelets, and an increased risk of cancer. The source cell says discharge from factories, and leaching from gas storage tanks and landfills.

The table notes put those figures in milligrams per liter unless otherwise noted. The notes say milligrams per liter are equivalent to parts per million. 0.005 mg/L is therefore 0.005 ppm on that note. It is not a different standard. Moving the same digits to micrograms per liter uses the 1,000-to-1 scale on milligrams and micrograms. 0.005 mg/L is 5 µg/L on that scale. Write both labels if the lab used the smaller unit, so a later reader does not think 5 is a new limit.

An MCLG is a goal. An MCL is the enforceable public number. Zero in the goal cell is not a second MCL sitting under 0.005. The definitions of those two words, and why a goal is not a fine, are on MCL and MCLG.

The 0.005 Figure in the 2025 CFR

Section 141.61 of the 2025 Code of Federal Regulations prints maximum contaminant levels for volatile organic contaminants. Benzene, CAS 71-43-2, is 0.005 mg/L. Vinyl chloride, the row above it on that table, is 0.002 mg/L. Those are not one number. The vinyl chloride row has its own page, vinyl chloride in drinking water.

Paragraph (a) says those volatile-organic levels apply to community and non-transient, non-community water systems. A private well is not named in that sentence. A dealer who copies the 0.005 line onto a kitchen-tap jug still has to say the jug is not the public-system rule. The difference between a city report and a private well is private well water regulations.

What Is the Benzene Mark on the BAT Table?

Table 2 of the same section marks best available technology for organic contaminants, except PFAS. The columns are granular activated carbon, packed tower aeration, and oxidation. Benzene is marked under granular activated carbon and packed tower aeration. The oxidation cell on that row is empty. Empty is not a quiet yes.

A mark is not a removal percentage. The table does not say what share of benzene a carbon bed takes out, how long the bed lasts, or what the equipment costs. A pitcher, a softener, and a UV lamp are not named on that row. Do not tell a household that a softener “handles benzene” because the word carbon appeared in a different column. The primary-versus-secondary distinction, so this enforceable line is not read as a taste standard, is primary and secondary drinking water standards.

Keep Benzene Apart From the Neighbors

The same volatile table also prints trichloroethylene at 0.005 mg/L and tetrachloroethylene at 0.005 mg/L. Sharing a digit is not sharing a name. If the lab wrote benzene, write benzene. If the lab wrote a different solvent, open that row. Adding the numbers together is not the rule this page fetched.

Carbon tetrachloride is also 0.005 mg/L on that table. A customer who hears “five” still needs the chemical name. The source story is different. Benzene's source cell is factories, gas storage tanks, and landfills. Do not paste a solvent story from a neighboring row onto this one.

A city customer may already have the row inside the annual report. Read the detected value, the unit, and the violation language on that report before you quote 0.005 from memory. A private-well customer does not have that report. Their sheet is one sample. Say so on the work order.

What to Write for Benzene in Well Water

1. The lab name for the analyte, so the row is not filed under “organics.”
2. 0.005 mg/L as the public line, and 5 µg/L only as the same line.
3. Whether the paper is a public-system result or one private-well jug.
4. The BAT marks as names, not as a removal percent.
5. No installed price from this page.

A water treatment dealer who saves those lines can explain the sheet without turning a public MCL into a private-well statute. This page does not diagnose anemia, does not rank filters, and does not tell anyone to stop drinking the water. Those conversations belong with the lab, the physician, and the authority that actually regulates the tap.

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