New England Radon Ltd
- Radon in Water
About 56,878 households in Rockingham County, 47% of the county, rely on a private well. Nobody tests that water unless the owner does.
In Rockingham County, roughly 47% of households, about 56,878 homes, draw their water from a private well. Nobody tests it, treats it or inspects it unless the owner does.
The rules that apply in Rockingham County are set at the state level in New Hampshire. The state does not require a test on a new well, and nothing is required at sale. Some counties and townships add permits or setbacks of their own, so check locally before drilling. The state's own recommendations are below.
No statewide water test and no state permit for a household well. The well must be constructed by a New Hampshire licensed water well contractor to the Water Well Board's rules (steel casing seated into bedrock or at least 20 ft, a watertight cap 12 inches above grade, and the setbacks in the subdivision and septic rules, 75 ft from a leach field for most lots), and the contractor files a well completion report with NHDES within 90 days, which puts the well in the state Water Well Inventory. Most towns require a bacteria test, and some a full Standard Analysis, before a certificate of occupancy; NHDES recommends the Standard Analysis on every new well before it is used.
No statewide requirement. RSA 477:4-c requires the seller to disclose the well's location, type, malfunctions and the date and results of the most recent water test, so buyers routinely test as a contingency, and FHA, VA and USDA loans require a bacteria, nitrate and lead sample from an accredited lab. Radon and arsenic are the results that most often hold up a New Hampshire closing.
NHDES recommends the Standard Analysis every three to five years and bacteria and nitrate every year, plus a test after any well or plumbing work, flooding or a change in taste, color or smell. The Standard Analysis from the state lab covers bacteria, nitrate, nitrite, arsenic, uranium, fluoride, chloride, copper, iron, lead, manganese, sodium, hardness, pH and radon. New Hampshire uses its own arsenic standard of 5 ppb, half the federal limit, and NHDES also suggests a one-time PFAS test for wells in the southern tier and near known contamination.
No statewide free program. The NH Public Health Laboratories in Concord sell the Standard Analysis kit for a modest fee (the radon vial is a separate sample), picked up at the lab or mailed, and NHDES interprets the results through its Be Well Informed web tool. Towns and regional planning commissions periodically run subsidized arsenic and radon screening, and the state has paid for PFAS sampling of wells near known sources.
The nearest certified lab is New England Radon Ltd in Salem, in the county. There are 7 more within 40 miles, listed below with what each tests for.
8 certified labs within 40 miles
Homeowner samples
Homeowner samples
Homeowner samples
Homeowner samples
Licensed help in Rockingham County includes Allied Clearwater and Aqua Specialties and 26 others. Every listing was matched to the New Hampshire license list; the "verify" link on each profile opens the state lookup.
28 licensed contractors
License 1354 Active
License 1561 Active
License 1956 Active
License 1381 Active
License 1627 Active
License 253 Active
License NYRD10954 Active
License 141 Active
License 1401 Active
License 1768 Active
License 650 Active
License 1445 Active
Well depth and water chemistry in Rockingham County follow the rock underneath it. Typical wells here run 240 to 480 feet; the median of 5,130 new domestic wells in the NHDES Water Well Inventory completed since 2000 is 320 feet. Contaminants worth testing for in this part of New Hampshire include arsenic (naturally occurring in bedrock, worst in the southeast from nashua and manchester to the seacoast, where about one well in five is over the state's 5 ppb standard), radon in water (granitic bedrock statewide.
240 to 480 feet; the median of 5,130 new domestic wells in the NHDES Water Well Inventory completed since 2000 is 320 feet
Neighboring counties: Strafford County, Hillsborough County, Merrimack County, Belknap County.
New Hampshire state lab: $15 bacteria, $85 standard analysis, $90 home buyer test. Installed costs are national 2026 ranges; local quotes vary with depth, access and materials. Sources, checked September 2026: NH Water Analysis Laboratory testing guide, HomeGuide cost guides, Angi: cost to shock a well.
About 56,878, or 47% of households, based on Census housing data and state well surveys. The share is highest outside the towns with public water.
New England Radon Ltd in Salem, inside the county. Call first to ask whether they accept homeowner samples.
No statewide water test and no state permit for a household well. The well must be constructed by a New Hampshire licensed water well contractor to the Water Well Board's rules (steel casing seated into bedrock or at least 20 ft, a watertight cap 12 inches above grade, and the setbacks in the subdivision and septic rules, 75 ft from a leach field for most lots), and the contractor files a well completion report with NHDES within 90 days, which puts the well in the state Water Well Inventory. Most towns require a bacteria test, and some a full Standard Analysis, before a certificate of occupancy; NHDES recommends the Standard Analysis on every new well before it is used.
Published lab fees in New Hampshire: $15 for a bacteria test. New Hampshire state lab: $15 bacteria, $85 standard analysis, $90 home buyer test. Mail-in kits cost about the same as walking in.