Taking the Key Step

Well development is often overlooked, but it is critical to the life of a well system.

By William Wagner

Well development is the last item on the to-do list in an installation, but that doesn’t diminish its significance. In fact, experts insist it’s the most important step in the entire process.

“Well development is often overlooked and underappreciated, but it sets the stage for success moving forward,” says Michael Schnieders, PG, PH-GW, the president of Water Systems Engineering Inc. in Ottawa, Kansas.

“You remove all the disruptive material, whether that’s a physical disruption of sediment, introduced drilling fluids that haven’t been fully evacuated, or just restabilizing the aquifer. In removing the material—the congested water chemistry—you improve those flow pathways and really set the well up for efficiency from a pumping and self-cleaning standpoint.”

Thom Hanna, RPG, a hydrogeologist with Aqseptence in Durango, Colorado, puts it this way: “It doesn’t matter if you’ve made a well out of solid-gold screen casing and used diamonds for the filter pack. If you haven’t done the proper well development, you don’t have a good well. That’s the simplest way to sum it up.”

To prevent dollars from turning to dirt, here are six key steps to remember when addressing well development:

Step 1: Incorporate well development into the design

A plan for the development stage should be mapped out even before a drill rig arrives at a jobsite. Among other things, the type of well screen or gravel pack that is chosen and the wellbore size can have an impact on well development. Too often, contractors don’t think this far ahead.

“The physical part (of well development) is done at the end, but you really have to start thinking about it in the design process,” Hanna says. “If you don’t design a well that you can properly develop—if you don’t specify the tooling and methods of development—you’re going to be behind the eight ball already.”

Water is pumped into a bucket as a part of well development so the water can be evaluated.

Step 2: Allow for adequate time

This can be a particularly tricky part of the equation. Says William Baldwin, MGWC, CVCLD, the CEO of Hawk Drilling Inc. in Ballston Spa, New York.: “Every job is different, so there isn’t really a time range.”

There are, however, some general rules that apply. For example:

“We’re finding with our finer materials, two or three hours is about all it takes with our development, and we don’t see any improvement after that,” Baldwin says. “On coarse screens, where you have a lot of different graded material, you can have anywhere from, say, eight to 24 hours of development time. But I’m talking larger municipal jobs. For residential, it’s not as much time.”

Baldwin has a simple workaround when he encounters a time-related predicament.

“What we do is put an estimated time in our quote based on that area,” he says. “Sometimes it’s more, sometimes it’s less. And since we have it at an hourly rate, people just pay whatever it happens to be.”

Step 3: Disruption is the name of the game

Once the planning and installation are complete, the actual well development takes place. The object here is to move various materials out of the flow pathways in order to create optimal pumping power and efficiency.

“You need some means of agitation for physical disruption,” says Schnieders, who was the NGWA Foundation 2017 McEllhiney Lecturer. “You typically want to start with low-pressure jetting. Then once you get some physical disruption, you purge and evacuate that material.”

Overpumping is often an important part of this process.

“The idea with overpumping is to move the material as fast as you can, more than what your designed pumping rate is going to be,” Baldwin says.

Air jetting is another common method, though its use depends on the composition of the well.

“Sometimes air jetting disturbs things in a way you don’t want to,” Baldwin adds. “With some of our real fine formations, we end up plugging up the screen if we air jet them. I’m talking real fine material.”

Step 4: Monitor the water

It’s not enough to produce maximum pumping efficiency and capacity. Equally vital is ensuring the water is clean. Therefore, various field tests should be employed throughout the development to monitor the water quality.

“Improper development can haunt a well,” Schnieders says. “Not only can it increase pumping costs, but it can also impact the water quality. If we fail to remove those fine sediments or drilling fluids, it can create an anaerobic condition that is a perfect breeding ground for nuisance bacteria.”

After water is pumped into the bucket, a field evaluation must be conducted to gauge solids output. A rule of thumb is 10 ppm sand equals approximately an amount of sand the size of a dime in the bucket.

Step 5: One size doesn’t fit all

Every well is unique, which means every well development job is unique. Among the factors that come into play are the drilling method, the geology, and design of the well.

“Each job we do is a little different, and you have to tailor the development to the type of formation you have,” Baldwin says. “You can either make or break a well. You can destroy it or make it a good producer.”

Consider some of the variables a contractor must navigate:

“If a drilling fluid has been used—some kind of mud or stabilizing agent—you’ll want to use a chlorination step,” Schnieders says.

“Twenty years ago, this wasn’t as important because we didn’t have as much polymer being used. Now, about a 1200-part-per-million chlorine solution is needed to shear those polymers and break them apart. If you’ve got a fine sediment in the formation, you may want to use a dispersant chemistry, such as Nu-Well 220 by Johnson Screens. Those help destabilize the clays so they can be evacuated.

“So the chlorine does part of the work in breaking down the polymer, and then these dispersants destabilize the physical nature of the clay so they can be evacuated. That makes subsequent mechanical methods more effective.”

The “one size doesn’t fit all” mindset also applies to redevelopment during the life of the well. Some wells might never need to be redeveloped, whereas others should be revisited every several years.

Part of this contrast comes down to the quality of the original well development. Says Schnieders, “It depends on how well the well was originally developed, or whether it was developed at all.”

In other instances, redevelopment is dictated by the well type.

“Alluvial wells tend to have a higher need for redevelopment,” Schnieders says. “If it’s a well that is run 24/7 with a maximum production yield, redevelopment might be needed as frequently as every seven years. But if you’ve got a well-constructed, well-developed, deep hard-rock aquifer, you may never need redevelopment.”

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The National Ground Water Association recently added an updated DACUM Geothermal Research Chart to its website. DACUM charts cover major duties and related tasks for occupations. This article covers some of the necessary skills and competencies for geothermal contractors. GO refers to the geothermal chart. The letter and number below refer to the skill on the chart. This article covers: DOG-1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11. More information on DACUM and the charts are available at www.NGWA.org/Certification and click on “Exam information.”

Step 6: Don’t take shortcuts

A video found signs of poor development in a well—drilling fluids visibly remain after the well has been put in service.

Since development takes place at the end of the project, there’s a temptation to let it slide. After all, budgets must be met, and impatient clients must get their wells up and running.

But if the experts have one piece of advice they stress time and again, it’s this: Don’t skimp on well development.

“You get down to that final point, and you have only so much time to develop the well,” Hanna says. “It’s like—‘Ah, I can come in under budget (by taking shortcuts on development). I can get this done.’

“But what you’ve done in that case is hand over a well to the owner that is going to cost a lot more to operate. You’re better off explaining that the budget is over in other areas and the one place where you don’t want to cut back is well development.”

You often find yourself fighting the nature of the business.

“It’s a fascinating industry we work in,” Hanna adds. “A lot of times there are misconceptions, and we do whatever is cheapest. But the value of doing it right is quite often much greater than building something inexpensively. Then you have to pay for it over the life of the well.”

William Wagner is an award-wining writer, editor, and project manager for Wagner Communications. He has written for magazines, newspapers, books, and websites. He lives in the Chicago area and can be reached at william.wagner7@gmail.com.

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