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California contractor license

Petersen - GPM Well Testing And Water Treatment Services LLC

Petersen - GPM Well Testing And Water Treatment Services LLC of Santa Rosa holds California license 985445 (C55 Water Conditioning, C57 Well Drilling, D21). The CSLB file dated Nov 1, 2026 lists it as active.1 It expires Jul 31, 2027.

Active

Petersen - GPM Well Testing And Water Treatment Services LLC, Santa Rosa

License
985445
Class
C55 Water Conditioning; C57 Well Drilling; D21
Expires
Jul 31, 2027
Bond
$25,000
Workers' comp
Insured to Jan 1, 2027

CSLB file dated Nov 1, 2026

From the CSLB file dated Nov 1, 2026. Not a consumer report; check the board before you hire.

Has the board taken action on this license?

None in the CSLB file dated Nov 1, 2026. Confirm with the board: CSLB license check

What bond, insurance and workers' comp are on file?

Bond
$25,000Harco National Insurance Company, from Jan 1, 2023, continuous
Liability insurance
Not in the CSLB fileCheck with the board
Workers' comp
InsuredService American Indemnity Company, from Jan 1, 2026, to Jan 1, 2027

Who is on this license?

Responsible managing manager
Matthew R. PetersenSince Jul 25, 2013

What work does this license cover?

Issued Jul 25, 2013.

Which other Santa Rosa businesses hold C55 Water Conditioning?

What should you check before hiring?

What to ask before you hire

  1. Get the license number in writing. The name on the license should match the name on your contract and invoice.
  2. Check the class covers the job. A license for one trade doesn't cover another. California license classes
  3. Ask for a certificate of insurance sent to you by the insurance agent, not handed over by the contractor. How to read a COI
  4. Ask who will be on site. If a crew works on your property, ask for proof of workers' comp. An exemption on file means the contractor told the CSLB it has no employees.
  5. Put it in a written contract: license number, price, start date and payment schedule. Check the license again on the day you sign.

If the license is lapsed

  1. Don't sign or pay a deposit until the CSLB shows the license active again.
  2. Ask the contractor why. For a bond or insurance lapse, ask for proof that the new bond or policy was filed with the CSLB, then check again.
  3. If work has started, hold further payments, keep the contract, receipts and photos, and file a complaint with Contractors State License Board (CSLB).
  4. Check another contractor. California license lookup

Sources

  1. CSLB License Master (cslb.ca.gov, Nov 1, 2026)
  2. Contractors State License Board (CSLB)