This Web site is an educational and outreach service of the Pennsylvania Ground Water Association, Inc.
Learn How To Use Stiff-Foam To Air-Rotary Drill Through
Caving Overburden at the PGWA 2014 Summer Field Conference
Friday, June 13, 2014 at the same location as last year west of State College, PA.
By Todd Giddings, Ph.D., P.G., Education Committee Chairman
Each year, for the past twelve years, the Pennsylvania Ground Water Association has held one-day, totally outdoor, summer field conferences that have had live demonstrations of water-well and geothermal borehole drilling, casing, grouting, development, test pumping, hydrofracturing, and decommissioning.
What will be demonstrated on Friday, June 13, 2014? We are going to demonstrate how to use Stiff-Foam to air-rotary drill through caving overburden. The Stiff-Foam drilling method uses significantly less air volume and creates a pseudo-wall-cake to minimize the collapsing of the caving overburden and to decrease the erosion of the borehole wall.
The Stiff-Foam air-rotary drilling method uses a polymer that is mixed into the water that is injected into the compressed air that operates the down-the-hole hammer. This water/air mixture also cleans the button bit (on the down-the-hole hammer) and carries the drill cuttings up the annular space around the drill rods to the ground surface. The polymer keeps the silt and clay and fine sand particles in the drill cuttings from aggregating (sticking together) into larger mud balls. By also coating the small particles in the borehole wall it creates pseudo-wall-cake which reduces the intrusion of the compressed air into the caving overburden and thereby reduces the collapsing of the borehole wall. A foaming agent is also mixed into the injected water and it forms small, very long-lasting bubbles (hence the name Stiff-Foam) that, by increasing the viscosity of the air stream, helps to carry the small clay, silt, and sand particles up the annular space. This increased carrying capacity of the Stiff-Foam bubbles means that a much lower air volume (and a lower air velocity in the annular space) is required to drill through the overburden. Hence the Stiff-Foam drilling method has been described as “tip-toeing” or drilling “very gently” through caving overburden.
This demonstration will be at the same location as the past two years, next to the Home Depot store at the I-99, Route 220, and Route 322 Exit 69, located just west of State College. In 2012 we demonstrated the case-as-you-drill method of air-rotary drilling through caving overburden, and in 2013 we demonstrated how to convert an air-rotary drill rig to mud-rotary drill through the same caving overburden. Both of these drilling methods usually guarantee success, while the Stiff-Foam air-rotary method does not have quite as high success rate. However, the Stiff-Foam air-rotary drilling method is easy and fast to set-up, and does not require any special equipment that the other two methods of drilling through caving overburden require.
The Gatesburg Formation overburden at this site is a silty and clayey sand material that is notorious for its caving conditions and flowing sand zones. A large commercial geothermal loop field was constructed across the street from this demonstration site by using mud-rotary drilling to keep the geothermal boreholes from caving in before the loops were inserted and then grouted in place. The caving overburden conditions at this 2014 PGWA Summer Field Conference site will provide a very good challenge for the Stiff-Foam air-rotary drilling method.
Who should attend? Air-rotary water-well drilling contractors who want to learn how to use Stiff-Foam, geologists, water-supply engineers, hydrogeologists, sanitarians, watershed specialists, water-supply regulators, municipal officials, planning commission members, members of watershed associations, water-well owners, Master Well Owners, and anyone interested in learning the Stiff-Foam technology that can overcome caving-overburden conditions.
Equipment manufacturers and suppliersto the ground-water industry and the geothermal industry should also attend and take advantage of this opportunity to display their products.
Pennsylvania State Police Motor Carrier Enforcement Officer Supervisor MitchellScalia will be back to do another walk-around inspection of a rig-tender truck this year. Officer Scalia will also discuss the PA CDL requirements. If you operate drilling equipment in Pennsylvania, you won’t want to miss this session.
There will be a concurrent session in the big tent on “How 45 years of water-table level monitoring can tell you a whole lot about the Gatesburg Formation”.
Why attend these demonstrations? This Summer Field Conference will demonstrate Stiff-Foam drilling technology that you may only have read about. By direct observation of this Stiff-Foam drilling demonstration, you will gain a much better understanding of how it works. As the Stiff-Foam drilling progresses, it will be explained step-by-step, and there will always be an opportunity for questions. There will also be a demonstration of a BubbleBuster unit that uses compressed air to turn the persistent bubble foam-cake into a slurry. There will also be tabletop displays and large equipment displays.
Registration is FREE for any employee or member of any federal, state, or local government agency or entity, Master Well Owners, faculty, and students. The PGWA Summer Field Conference Site is at the same location as last year on the northwest side of State College, and a detailed location map with driving directions is available by clicking the link below.
This PGWA Summer Field Conference program will provide 4.5 Professional Development Hours (PDH’s) for licensed Professional Geologists and licensed Professional Engineers. PGWA will provide Certificates of Participation for 4.5 PDH’s upon request to P.G.’s and P.E.’s who attend. Check the Certificate of Participation request box on the registration form.
For hotel, motel, bed-and-breakfast, campground, and local attraction information, click this link.
For a location map with driving directions, click this link.
To print a PAID registration form for the Summer Field Conference and Trade Show, click this link.
The registration deadline is Friday, June 6, 2014.
For a Trade Show exhibitor display table registration form, click this link.
To qualify for a Free Registration, you must be an employee or member of any federal, state, or local government agency or entity, a Master Well Owner, or a teacher or student. Commission and authority members and employees also qualify for a free registration.
To submit a FREE Registration form, click this link. After you fill out your Free Registration form and submit it, you will receive an email confirming your Free Registration to the PGWA Summer Field Conference.
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