When you buy a home in the mountains, you feel like you’re on top of the world, at the pinnacle of the food chain and even the watershed.

You drill a well and out bubbles clear, sparkling “Rocky Mountain Spring Water.” Snowmelt filtered through ancient stone, that sort of thing. I’m the kind of person who analyzes the ingredients list on just about everything I eat. But somehow I’d never questioned what might be in the water I’ve been drinking for nearly two decades.

Recently, though, my wife, Mary, and I decided to obtain a comprehensive analysis of our well water. Over the years we’ve lived in Colorado’s Wet Mountains, Mary developed hypothyroidism and my son, Harrison, was diagnosed with autism. And apparently I may have attention-deficit disorder. Sometimes I’ve wondered whether some of these problems have their origins 150 feet underground.

We sent water samples to the Colorado Department of Health to test for a number of standard pollutants, including bacteria, toxic chemicals, minerals and heavy metals. Since there are abandoned thorium mines in the area, we also tested for this radioactive substance. It should be noted that there is no aquifer here; wells are drilled into the bedrock and capture water from cracks created by millions of years of geologic activity.

We’d had the water tested locally for bacteria several times and never received a positive result. In fact, the only reason we’d tested for bacteria was because such a test was included in the package. So imagine our astonishment when the day after we mailed the samples we got a call from the lab saying our water was considered unsafe for human consumption, or even bathing, because of e. coli and total coliform bacteria. Do not allow it to contact open cuts, I was told. This is “very dangerous.”

We were advised to “shock chlorinate” the well. This involved a fairly detailed procedure: pouring a carefully measured amount of bleach down the well, running the outside hose back down the well to disinfect the casing, and then opening every faucet in the house to disinfect the pipes. We waited overnight, then ran all the water out of the well and onto the driveway until the outflow no longer smelled like chlorine.

A couple days later, a new test sample was found to be free of bacteria. That was all fine and dandy, but we were worried now. We decided to continue buying water from treatment devices at two health-food stores we frequent while we awaited test results on the rest of the chemistry.

Good call. Because as information trickled in, we learned we had double the EPA-allowable level of lead in our water, and over-the-limit levels of nitrate-nitrite as well. The lab report on our well warned against drinking and cooking with the water, and said that it posed a risk to crops such as celery and green beans. At the same time, it stated that it was rated “excellent for all classes of livestock and poultry.” Yeah, right.

Also present were subtle hints of uranium and thorium, though both were well within levels considered safe by the Environmental Protection Agency. Most troubling was the report on lead. There is an old lead mine a few miles down the road, but it never occurred to us we’d find lead in our water, even after the EPA tested roads in the area a few years ago because they’d been surfaced with tailings from the mine. Hypothyroidism, autism and ADHD have all been linked to lead toxicity. Maybe that explained some of the weird things around here. Then again, maybe not.

This entire exercise made me think about all the other folks across the heavily mineralized West who may be drinking contaminated water. Very few people go to the trouble and expense of having their water tested.

But even testing may not give an entirely accurate picture. Consider that a subsequent retest by the state found no lead in the water, although it did find a renewed presence of coliform bacteria along with higher levels of nitrate than the first test. Perhaps testing is just a snapshot of whatever is present at the time the sample is taken.

The only sensible solution is to treat the water, a potentially expensive proposition, but more logical than drilling a new well. Well water just doesn’t come with an easily obtainable list of ingredients, and even the ingredients you know about seem subject to change from week to week. The best advice is to test your water, knowing that you’re only getting a snapshot of what may be in it, and treat it accordingly.

Hal Walter is a contributor to Writers on the Range, a service of High Country News (hcn.org). He writes in Westcliffe, Colorado.