Well rehabilitation has become a field of interest as people become more interested in reclaiming existing wells than simply abandoning them to start over. The main reason usually is the sometimes very high cost of finding a new location (getting it approved), drilling and testing, and the logistics of powering a pump and piping water. As drillers know, their costs in this list are almost minor. In plume management and clean-up, you may not have a choice to move over. That well that is failing was put in that particular spot for a good hydrologic reason (wasn't it?). This is the same for problem monitoring wells. Sometimes the only alternative is to attempt to rehabilitate such wells.

Now we run into the "how" part. There are many opinions and conflicting views: What chemicals to use? What development method? How long to work it? How to evaluate? The chemical part is particularly confusing with various blends now on the market. Some of these make extraordinary claims. Their actual performance under varying circumstances needs to be validated, and their chemical mode of action made known. Otherwise, I do not see how a driller or well operator can make an objective decision for a particular job.

We DO KNOW that it is possible to specify a well-cleaning blend for a specific known problem need (for example, iron biofouling in a tight sand formation). These can be specified based on simple, but effective testing. As for the chemicals, this grizzled old vet in well rehab planning and research personally advises caution and specifying chemical blends by generic name and quantity (“so much glycolic, amended by so much sulfamic and polymer in so much water, etc.). If the name-brand blend meets those specific qualifications, fine. Don't buy on sales pitch alone. If you don’t know this stuff, call us, will you, and reap a benefit?

Then we have old reliables: "I have always used two carloads of muriatic in all my wells. If the grout can't take the pressure, that's just too bad. They need to drill another well." I exaggerate, of course (don't I?). The time has really come for those who have done it the same old way forever to take a look at alternatives. We DO KNOW that muriatic and chlorine are not the answer to everything. They are dangerous and not that effective actually. There are less dangerous and more effective ways to deal with iron biofouling, for example. We DO KNOW that phosphorous-containing cleaners and additives are prone to encourage regrowth and that it is very difficult to remove them totally (and it doesn't take much to restart a clogging biofilm that can then sustain itself). We DO KNOW that chlorinating afterward is not the antidote to putting essential nutrients in the hole.

We DO KNOW that rehabbing plume control and pumping wells requires another level of caution, consideration, and expertise. The chemical tool kit is much smaller (in the case of the ASTM Standard Guide for monitoring well maintenance, there is no toolkit). The results less certain. The possibility of failure is higher.

It seems sometimes that less thought and expertise is going into these projects than should be the case. The reason is a lack of foresight about the difficulty of the operating conditions of these types of wells in budgeting and planning for their operation, including material selection and even basic well design.

We DO KNOW that all well rehab requires time, patience, and effective development motion to work. Many methods work very well under specific circumstances: Sonar Jet, AquaFreed, and conventional surging and jetting (done intelligently) (See “Innovations in Well Rehabilitation” in the articles section on this web site.). I have recently become a fan of the Airburst Method. Day in and day out, I am personally a fan of the cable tool rig with air compressor for workover purposes. With proper tools, air amendment, etc., you have all you really need: a hoist, an effective means of forcing an in-and-out motion, a slurry pumping system (various bailers plus airlift), all at relatively low hourly cost. It is not the only effective system, but I suggest that you rotary hotrods should not let the old 22W rust away just yet. This can be new life for it.

We ALSO KNOW that rehabilitation is ONLY THE START OF RECOVERY for the rehabbed well. The tendency is to get it back in operation and then go on. The actual thing to do is to plan for when the deteriorating conditions will return. We KNOW they will.

We KNOW from study and experience that maintenance monitoring (see other articles and our publications on this web site) and preventive treatment are both effective and less costly than waiting for failure and rehabbing again. This can be a service opportunity for many well contractors. It is this MAINTENANCE that will keep the well operating far into the future. That keeps wellfields from becoming pipelines, folks.

We DON'T KNOW the full answer to the economics of well rehabilitation and maintenance. The last nationwide economic studies of rehabilitation processes were done in 1960 in the United States. The relative economics of maintenance as a policy versus crisis-reaction management are developing based on studies by colleagues of mine in England. From that, we are CONFIDENT TO A HIGH DEGREE OF CERTAINTY that a maintenance policy saves a lot of money over a wellfield life cycle. Perhaps more valuable information will be coming in the near future.

We DON'T HAVE a "one-size-fits all" recommendation -- would you expect one? -- because each well situation is different. What we DO KNOW is that with testing and careful planning and competent execution that effective well rehab is possible. We DO KNOW that it must be followed by a maintenance program or the rehab is a TOTAL WASTE of MONEY. Both testing and the maintenance are do-able by any competent driller and water treatment or remediation treatment plant operator with the right knowledge.

So go deeper, Dear Reader. Go past the fiery sales preaching and graphical glitz and study the scriptures: the available literature on well maintenance and rehabilitation is there for all to read. And WE KNOW we can teach you what you need TO KNOW.

We keep track of this information (as do some other worthies). See the links offered from our home page.

Of course, I highly recommend my pocket book on the subject -- Monitoring and Remediation Wells -- Problem Prevention, Maintenance and Rehabilitation from CRC Press CRC Press Lewis Publishers.

You can visit the rest of our web site for some basic information. Take some time and check it all out during a slow period or occasional off evening. Watch for our training events. Then go forth armed to take good care of wells.