Before you spend a dollar, confirm the result
The first call people make after a failed test is to somebody selling equipment. That's backwards. A single lab result is one sample, from one tap, on one day, handled by one person, and any of those links can produce a number that isn't true of your water.
Sampling error is real and it's common. A tap with an aerator full of biofilm, a hose bib, a sample bottle touched on the inside, a bottle that sat in a hot truck for a day, a preservative that wasn't right for the parameter. Bacteria results are the most sensitive to all of this, which is exactly why bacteria is the parameter that gets falsely flagged most often. A garden hose sample tells you about the hose.
So retest before you react. Same lab or a different one, a proper cold water tap with the aerator off, run to clear the line, sterile bottle, straight to the lab inside the hold time. If the second result agrees with the first, you have a real finding and you can spend money with confidence. If it doesn't, you just saved yourself a treatment system you didn't need. The one exception to waiting is drinking water while a bacteria result is unresolved, which is covered below.
Sort the report into two piles
Lab reports don't tell you which numbers matter. They just list everything with a limit next to it, and a homeowner reading it at the kitchen table sees fifteen lines and assumes the water is poison. Most of the time it isn't.
The first pile is aesthetic, sometimes called secondary or nuisance parameters. Iron, manganese, hardness, sulfur smell, total dissolved solids, pH on the low or high side, color. These stain fixtures, ruin laundry, taste bad, smell like rotten eggs, eat up a water heater and clog a pump. They are not a health emergency and nobody needs to stop drinking the water over them. They're also the easiest category to treat, and the treatment is well understood equipment that's been doing the job for decades.
The second pile is health based. Total coliform and E. coli, nitrate, arsenic, gross alpha, uranium, lead, volatile organic compounds, radon in water. These have standards behind them because of what they do to people, not what they do to a sink. A number over the limit in this pile deserves a specific response, and the response is different for each one.
Coliform and E. coli: what to do today
Total coliform positive means stop drinking the water and stop cooking with it until it's resolved. Use bottled water, or bring water to a rolling boil for one minute and let it cool. Boiling handles bacteria. If E. coli came back positive on top of the coliform, that's an indicator of fecal contamination and it's the more serious version of the same finding. Treat it the same way and move faster.
Here's the part most homeowners don't hear. Coliform in a well is far more often a construction problem than a water problem. The aquifer down in the rock isn't teeming with bacteria. Surface water is, and coliform in your sample means a path most likely exists between the surface and the inside of your casing. A cracked or loose well cap. A cap with a missing vent screen that lets insects in. A casing cut off at or below grade with runoff pooling against it. Deteriorated grout in the annular space. A bad seal at the pitless adapter. On an old dug or spring fed well, the whole structure.
That's why chlorine alone isn't the repair. Shock chlorination disinfects what's in the well right now, and if the entry point is still open the bacteria comes back in a month and you do it all again. The real sequence is find the path, fix it, then shock chlorinate, then flush the chlorine out of the well and the house, then wait and retest. A retest too soon while chlorine residual is still in the system gives a clean result that means nothing.
If repeated repairs and repeated chlorination don't hold, continuous disinfection at the point of entry, an ultraviolet system or a chlorine injection setup, is the durable answer. It's a good answer. It just shouldn't be the first one, because it treats the water instead of closing the hole.
The other health parameters, one at a time
Nitrate. The drinking water standard is 10 milligrams per liter measured as nitrogen. Above that, the specific and urgent concern is infants under six months of age, where nitrate interferes with the blood's ability to carry oxygen. Pregnant women are also advised to avoid it. Critically: boiling makes nitrate worse, not better. Water evaporates and nitrate stays, so a boiled pot is more concentrated than what came out of the tap. If nitrate is high and there's a baby in the house, use bottled water today and sort out treatment after. Nitrate in a well often points at a septic system or fertilizer nearby, which is worth investigating alongside any treatment.
Arsenic. Naturally occurring in the bedrock across a lot of northern New Jersey, and New Jersey's standard is tighter than the federal one. It's a long term exposure concern rather than something that hurts you this week, so there's time to do this properly. Treatment is real and effective, either adsorptive media or anion exchange at the point of entry, or reverse osmosis at the kitchen tap if the goal is drinking and cooking water only. Which one depends on the arsenic concentration, the form the arsenic is in and what else is in the water, which is a lab question.
Gross alpha and uranium. Also naturally occurring here, from the same bedrock that puts them on the required test panel in Sussex, Passaic, Bergen and Morris counties. Gross alpha is a screening measurement of alpha radioactivity, and a high gross alpha commonly leads to a follow up test to identify what's driving it. Uranium responds well to anion exchange, and reverse osmosis at the tap is a point of use option. Neither result means the well is ruined or the house is unsafe to live in.
Lead. Lead in well water most often comes from the plumbing rather than the aquifer. Old solder, brass fittings, an older submersible pump or the drop pipe fittings. A useful diagnostic is a first draw sample compared against a flushed sample. A big difference points at the house plumbing, a similar number in both points at the well side. Fix the source where you can find it, and filter certified for lead where you can't.
VOCs and radon in water. Volatile organic compounds are man made and mean something upstream, an old tank, a spill, a former commercial property, so the source matters as much as the treatment. Granular activated carbon at the point of entry is the standard approach. Radon in water off gasses into the house air when you shower or run the dishwasher, and aeration at the point of entry is the usual treatment. New Jersey handles radon in water differently than a parameter with a hard enforceable limit, so ask the lab and your county health department what the current guidance is rather than taking a salesman's word for it.
Treatment gets sized from the raw water numbers
Nobody can specify a treatment system by looking at your basement. The equipment gets sized from the test, and not just from the parameter that failed. A softener sized without knowing the iron content fouls. Arsenic media that works fine at one pH does poorly at another. An ultraviolet lamp is only as good as the clarity of the water reaching it, so iron and turbidity have to be handled upstream or the lamp is decorative. Anion exchange for uranium behaves differently depending on the sulfate in the water.
That's the real reason a full raw water panel comes before any purchase. The test is not a formality, it's the specification. A contractor who quotes you a system without asking for the numbers is guessing, and you'll find out he guessed in about eighteen months.
Size it for the house too. Point of entry treats everything, which is what you want for anything that matters in a shower or a washing machine, radon and iron and bacteria included. Point of use at one tap is cheaper and is a reasonable choice when the concern is only what you drink and cook with, which is the case for some arsenic, uranium and nitrate situations. Those are different price points and different answers, and the right one depends on the parameter.
After the system goes in
Retest once the equipment has been running and flushed in, and test both the raw water and the treated water. Raw tells you the well hasn't changed. Treated tells you the system is actually doing what it was sold to do. Keep that first post installation report, because it's your baseline and every later test gets compared against it.
After that, a reasonable cadence for most private wells is bacteria and nitrate annually, and the fuller panel every three to five years or after anything changes. Anything changes means a new well or septic nearby, construction on the road, a pump replacement, a flood, a long drought, or water that suddenly tastes, looks or smells different. Any of those is a reason to test regardless of when the last one was.
Treatment equipment also has a maintenance schedule that isn't optional. Media beds exhaust, ultraviolet lamps lose output long before they burn out, sediment prefilters plug, softener brine tanks need salt. A system nobody services is a system that stopped protecting you at some point you didn't notice.
Call 973-853-1550 with the lab report in your hand. Reading the actual numbers off the page is a five minute conversation that tells you whether you're looking at a well cap, a filter, or a real treatment system, and it beats guessing from a search result.