Anthony CostelloLicensed

Licensed septic contractor based in Washington, Sullivan County, NH

"Based in" is the city and county of the address on the business's license record. That can be a mailing address; it doesn't tell you where the business works.

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What this license covers

• Design: licensed to size and lay out a septic system for a specific site and soil condition.

How to verify this license

We publish the license details exactly as they appear in the official licensing records of the agency that issued the license; we do not vouch for the business itself. Before hiring, look up license #01846 directly with the agency that issued it, confirm it is still active, and ask for a current certificate of insurance.

Source: NH DES - Septic System Designers & Installers, last checked 2026-08-16. Verify at the official source.

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