1. Grouting & Placement For Geothermal Applications Presented by Stewart Krause Wyo-Ben, Inc. Billings, MT

2. Why Grout? Prevent surface water from entering aquifers Prevent co-mingling of aquifers Enhanced Loop Performance Fill All Void Spaces In The Annular Space Maintain Moisture In The Annular Space

3. To establish and maintain a seal against all void spaces of equal or lower permeability than that of the least permeable formation intersected. Match thermal properties of the formations to the grouting materials to maximize loop performance & cost. Objective of Grouting:

4. Typical Grouting & Earth Material Thermal Conductivities Ref. Dr. Charles Remund Bentonite Grout.40 Neat Cement.55 Dry Bentonite Chips.20 Saturated Bentonite Chips.50 TG85.85 Dry Sand.20 Saturated Sand1.40 Heavy Dry Soil.50 Heavy Damp Soil.75 Heavy Saturated Soil1.40 Average Rock1.40 Dense Rock2.00

5. Soil Thermal Conductivity Ref. VA Dept of Mines & Minerals

6. Hole Diameter Squared Divided by 24.5 = Hole Volume in Gallons per Foot EXAMPLE (4.5 inch Hole) : 4.5 x 4.5 = 20.25 / 24.5=.83 gpf Calculating Hole Volumes

7. Product Sheets Listed information should include Mixing ratio Density Thermal Conductivity Product Yield

8. Commonly Used Grouting Materials Cement Grouts High Solids Bentonite Grouts Thermally Enhanced Bentonite Grouts

9. Cement Grouts Available—Easily pumped—Structural—Easily Probed vs. Heat of Hydration—Subsidence—Shrinkage Commonly Used Grouting Materials

10. Cement Grouts Neat Cement Engineered Cement Grouts Mix 111

11. Cement Grouts Neat Cement 5.2 Gallons Water 94# Type 1 Cement

12. Cement Grouts Engineered Cement Grouts Bentonite Plasticizers Retardant Accelerators Filtrate Control Sand

13. Cement Grouts Mix 111 6.19 gallons water 94# Type 1 Cement 21 oz Super plasticizer 1.04# Bentonite Ref. M.L. Allan @ Brookhaven National Laboratory

14. High Solids Bentonite Grouts Pumpability—Low permeability—Cost—Flexible vs. Difficult to probe—Subsidence Commonly Used Grouting Materials

15. High Swelling Bentonite Products Effectively Create Seals Restricts surface water penetration to lower aquifers Restricts inter-aquifer mingling and artesian flow Keeps moisture around sands in the annular area Fills all void spaces in the annular area

16. Dispersed –Granular –Powder Encapsulated –Granular High Solids Bentonite Grouts

17. Thermal Conductivity.43 to.45 Solids Content 15% 20% 30% High Solids Bentonite Grouts

18. Calculating Solids Content Grout Weight ÷ (Water Weight + Grout Weight) = % Solids (By Weight) Example: 50 ÷ 250 =.20 or 20% Solids 50 lbs. (Bentonite Grout) 200 lbs. (24 Gallons Water) + 50 lbs. (Bentonite Grout)

19. Flowable High Solids Bentonite Grouts

20. Develops Gels When At Rest High Solids Bentonite Grouts

22. With Densities Greater Than Water, High Solids Bentonite Grouts Will Easily Displace Water & Fill Voids

23. High Solids Bentonite Grout’s Flowable Nature Allow It To Seal Into Voids And Establish An Excellent Bond With All Surfaces.

24. Thermally Enhanced Bentonite Grouts Pumpable—Flexible—Low permeability vs. Some subsidence—Cost — Labor Commonly Used Materials for Grouting

25. Thermal Conductivity.93 @ 200 lbs. Sand 1.20 @ 400 lbs. Sand Solids Content 64% 71% Thermally Enhanced Grouts

26. Thermal Conductivity Testing

28. Objective Behind Grouting TO ESTABLISH AND MAINTAIN A SEAL AGAINST ALL VOID FACES, WITH AN EQUAL OR LOWER PERMEABILITY THAN THE LEAST PERMEABLE FORMATION INTERSECTED.

29. Type Of Grouting Material To Be Placed Depth To Be Placed Local Regulations (allow for pulling the temmie pipe or bottoms up) Specification Requirements (tremmie pipe size limitation) Choosing Grouting Material & Equipment

30. Equipment

31. Gear Pump

32. Progressive Cavity Pump

33. Piston Pumps

36. Mud Balance Water Volume Record Keeping Thermal Conductivity Site Testing

37. Sealing Boreholes While Utilizing Thermal Energy “Is” Protecting Our Children's Future Wyo-Ben, Inc. Billings, MT

38. Questions ?