|Brett Smith, owner of All’s Well in High River, Alta., circulating Boresaver Ultra C to treat a well with iron bacteria issues. The product turns a greenish colour when active.
Baker refers to iron bacteria as “nuisance bacteria” due to the slime problems associated with their presence in wells, cribbed wells and cisterns. “Odour and discoloration of the water are usually the first things customers notice, but it can become a more extensive problem,” he says. “You see well yield reductions and fouling and plugging of water treatment systems (inline sediment filters, reverse osmosis units, and media-based filters) with slime, as well as water lines and even submersible pump screens.” Baker asserts that if things have got to that point, maintenance is no longer an option and full remediation of the well and the filtration system is needed – which is both costly and time-consuming.
The traditional treatment practice, Baker explains, involves pouring household bleach or varying concentrations of 12 to 60 per cent chlorine in granular or liquid form directly into the top of the well. “Circulation or flooding the well with water was considered an important part of the procedure, but it wasn’t always done due to limited access to well or inability to haul larger volumes of water,” Baker notes. This procedure of overwhelming the iron oxide bacteria with high doses of chlorine came to be known as “shocking” the well, and it became the industry standard for removing iron bacteria. “Although it gave the owner peace of mind, later studies showed that it wasn’t an effective solution at all,” Baker notes. “The corrosive nature of the chlorine was considered an accepted risk and the iron bacteria were controlled temporarily, but would always return – sometimes worse than before.”
Baker Water Systems adopted a treatment that involves adding five gallons of 12 per cent acetic acid to the well (lowering the pH of the water makes chlorine less corrosive) followed by circulation to dilute and disperse the acid. Secondly, a five-gallon dose of 12 per cent chlorine is added, followed by continuous circulation. The well is then flushed with fresh water to force the chlorine into the aquifer around the well bore. “All this is completed from the top of the well casing, and the chemical mixture varies depending on the depth and the severity of the iron bacteria,” says Baker. “But this practice has its limitations and risks. Mixing the acid with chlorine produces dangerous gases and, although it appears that the treatment has done a good job, it doesn’t eliminate the iron bacteria completely. Regrowth is to be expected and regular maintenance will always be necessary.”
Newer treatments: pros and cons
Baker says there are many products available to treat iron bacteria issues. They involve chemical and mechanical rehabilitation processes that usually boast amazing results, but, he says, the costs of the chemicals are astronomical and the processes are very labour-intensive. “Trying to convince customers to spend thousands of dollars to treat a well when they are accustomed to spending only a few hundred for ‘shocking’ is difficult, to say the least,” he notes. “You also have to manage expectations, because the customers who do choose a more expensive treatment go into it expecting some kind of guarantee, which isn’t possible.” Baker adds, “I’ve seen a few of these treatments and the results are typically good, but the expense and the fact that in some cases, the treatment lasts no longer than a basic ‘shocking’ treatment makes them of questionable use. Customers have been very vocal with their disappointment.”
About six months ago, Baker was introduced to Boresaver Ultra C by his business supplier (and the Canadian distributor of the product), Brian Reierson of Ability Pump & Equipment in Calgary, and decided to give it a try. It’s a proprietary blend of monohydrates and organic acids created in Australia and brought to North America by Laval Underground Surveys of Fresno, Calif. “It’s been shown to be 10 times more effective than other products at removing iron oxide and iron bacteria,” says Laval global product manager Steve Strong. Boresaver Ultra C is certified by NSF International (an independent, nonprofit organization that provides standards development, product certification, auditing, education and more) for use in potable water supplies.
“I had two wells in particular that were having reoccurring iron bacteria problems, even with scheduled treatments,” Baker notes. “The process is simple and the product safe to handle. I poured it into the top of the wells, left it to circulate for a period of time and then flooded with fresh water.” In both cases, the results were very good. “In the first well, Boresaver Ultra C increased well yield by 1 igpm,” says Baker. “With the second well, in the past it has needed scheduled iron issue maintenance every six to eight months, but it’s been five months since treatment with Boresaver Ultra C and thus far there are no indications that would suggest the return of the iron bacteria.”
Although you can use the product in this way, Strong says, “We recommend using a purpose-built cable tool rig and an inspection camera to record pre-treatment and post-treatment results, and to be able to gauge the correct amount to use to achieve maximum results,” says Strong. “You can use it by doing a water sample test or visual inspection, but it’s much more effective to verify the severity of the issue by using a camera.” Strong did a presentation on Boresaver Ultra C at the CanWell conference in Hamilton on May 24, and Laval Underground Surveys also had a booth there.
Baker thinks the cost of Boresaver Ultra C treatment is very reasonable. “It’s about $1,000, which is about double the cost of ‘shocking’ – which I don’t do anymore – depending on a few factors, and it’s certainly more affordable than other labour-intensive treatments, which range from $2,000 to $4,000,” he observes. “But you also have to look at the long term. If a customer is paying for iron bacteria treatments twice a year for a few hundred dollars each time and this treatment is more expensive but you don’t have to do it nearly as often, the benefits become clearer.”
Baker adds: “Iron issues will always be there, and this product has the potential to be a cost-effective and long-term maintenance solution for the customer. Further field testing on the many different consistencies of iron bacteria and iron oxides along with service technician and customer feedback is the first step.”
Brett Smith at All’s Well Filtration & Pumping Solutions in High River, Alta., has also given Boresaver Ultra C a try. “Although I don’t have long-term results to discuss, the outcomes seem to be good,” he says. Smith applied it to two neighbouring wells about two months ago and another well in late April (two weeks before this interview). Each time, he applied the product, circulated for 45 minutes, let the treatment sit for about 20 minutes and then circulated again for another 20 to 30 minutes. He then introduced 150 to 200 gallons of fresh water to back-flush to push the treatment into the aquifer, letting the treatment sit for a minimum of 12 hours before pumping off. (Like Baker, Smith has used acetic acid and chlorine for iron bacteria issues in the past.) “With the wells two months ago, they did ultraviolet violet measurements afterwards, and that showed good results,” Smith reports. “I see Boresaver as a specific treatment, a tool that’s nice to have in situations where iron bacteria are an issue. The other big attraction with this product is that it’s biodegradable. You can tell customers that and they really appreciate it. After treatment, the water can be pumped onto a lawn or field with no worries.”
David Hanson of Design Water Technologies (a Minnesota-based consulting firm) developed a dual product line to treat iron bacteria in wells, pipelines, heat exchange units, and plumbing/piping called Unicid. It was developed over two decades ago and has been used in over 29,400 wells over the last 21 years worldwide. Hansen says it provides virtually zero return of bacterial problems. He has seen only 15 wells had a recurrence, which was due to physical factors in the well (such as corrosion in the well casing or failed/no grout) that allowed a recurrence of the organisms. He says their lab can predetermine if this problem exists and will warranty chemistry, if done. The products are shipped as non-corrosive, non-hazardous substance. Canadian distribution began last year.
“Unicid Catalyst penetrates and breaks up iron bacteria sludge and Unicid Granular fully dissolves it,” explains Hansen. “Because the buildup of live and decayed bacteria is completely removed from the borehole, there are no remaining nutrients for iron bacteria in the water to attach to and feed on.” The products are applied together into a well, followed by a development and monitoring procedure to determine when the well is clean, followed by flushing. Low pH (below 4.5) may kill grass, and a neutralizing agent can be added before flushing. The entire process of cleaning a domestic well can take from about four hours to a day and a half. Total cost of the treatment is $2,500-$3,000.
Hanson adds that because iron bacteria, coliform, and E. coli are found in the top two inches of soil, he believes it’s important to avoid things like laying pumps on the ground when servicing or installing them. “Keeping equipment intended for wells away from bacterial sources is what we as professionals should be doing.”
Treena Hein is a science writer based in Ontario and a regular contributor to Ground Water Canada.