William A. McEllhiney Distinguished Lecturer Series Well Technology

1. William A. McEllhiney Distinguished Lecturer Series Well Technology Made possible by a grant from Franklin Electric Company to the National Ground Water Research and Educational Foundation

2. To foster professional excellence in water well technology, the National Ground Water Research and Educational Foundation has established the William A. McEllhiney Distinguished Lecture Series in Water Well Technology. Initiated in 2000, the lecture series honors William A. McEllhiney, who was the founding president of the National Ground Water Association in 1948, and a ground water contractor and civil engineer from Brookfield, Illinois. NGWREF McEllhiney Lecture Series

3. "McEllhiney and the other founders of the Association saw several primary functions for the new national group," explains Foundation Executive Director Kevin McCray, "including serving as a clearinghouse for information and its dissemination, serving as an intermediary in coordinating advances occurring in different parts of the country, and serving as a place to bring contractors together so that they might have a working knowledge of contracting from all parts of the nation. NGWREF's McEllhiney Lecture series promotes and perpetuates those original aims." NGWREFMcEllhineyLectureSeries

4. Annually, a panel of ground water contractors invites an outstanding ground water contracting professional to share his or her work with the industry. Individuals may nominate themselves or others they believe to be qualified to serve as the NGWA McEllhiney distinguished lecturer. NGWREFMcEllhineyLectureSeries

5. Effective May 2005, Franklin Electric Co., the world's largest manufacturer of submersible electric motors, has agreed to underwrite the next three years of this lecture series for presentations to organized groups of contractors and other qualified and interested parties. Meetings and conventions of state and regional associations are eligible. Foreign associations of ground water contractors, academic institutions teaching water well technology, gatherings of water well regulators, and other bodies with a direct and identifiable interest in water well design and construction are eligible as well. NGWREFMcEllhineyLectureSeries

6. 2011 Lecturer Tom Christopherson Program Manager for the Water Well Standards and Contractors Licensing Program for the Department of Health and Human Services/State of Nebraska NGWREFMcEllhineyLectureSeries

7. The Nebraska Grout Task ForceResearch: Unexpected Results-New Solutions NGWREFMcEllhineyLectureSeries

8. Grout studies prior to 1999 State revised standards in 1999… Laboratory controlled to protect State Natural Resource… Controlled Environments adopts industry standard… Segmented constructs ultimate well. In-situ Bentonite cracks but will rehydrate Limited depth Is limited in how high % can be pumped Historically destructive Cementisious Grouts- Universal material Bond logging Cracks horizontally- bonds to everything Prevailing Technology

9. “Full length grout provides maximum protection to the ground water”… “When in doubt- Grout”… “All grout materials are alike”… Conventional Thinking – The Magic Bullet

10. UNLDemonstration

11. “ The Sun revolves around the Earth”… “ The World is Flat”… “ If man was meant to fly, God would have given him wings”… Conventional Thinking – Historical Perspective

12. In-situ Study Visual component Allows full length perspective Studies differing geologic conditions Real world testing Dye testing Limitless time frame for study Non-destructive Effective for all types of grout materials Led to new discoveries beyond study [ picture of clear casing ] Nebraska Grout Study- Changes Conventional Thinking

13. Site Assessments- Monitoring • All sites tested for; • Water Quality • Contaminates • pH • Chlorides • TDS • Soil Analysis • Contaminates • Particle size • Moisture content

14. Pilger- Stanton-area Moist Subhumid (20-38-in) Glaciated – Multiple Aquifers Water Table 28-38 feet bgs Perched Water Potential UZ - 3 Loess Deposits Grand Island Subhumid (17-39 in.) (25 in. ave) Platte River Valley – Unconfined Alluvial Aquifer Water Table (13.5 - <22 Ft) UZ – Mainly Sand Research Sites • Trenton • Semiarid (<10 - >29 in.) • Single Aquifer System • Water Level - • 34-35 ft bgs • UZ – silt with sand • Lake McConaughy • Semiarid (12.6 – 24.5 in.) • Unconfined Ogallala Aquifer • Water Table 132-142 ft bgs • UZ – Fine-Medium Silty Sand/Sandstone

15. Well Construction

16. Well Construction-Closed Loop

17. Rating System 0= No Data 1= Good 2= Cracks and Small Inconsistencies 3= Voids and Detachments Visual Assessment

18. Bentonite Slurry Code #1 – Good Code #3 – Cracks and Voids Code #2 – Cracks

19. Code #1 Code #3 Bentonite Chip Code #2

20. Closed Loop Slurries-Code #3

21. Cement-Based Code #1 – Neat Cement Code #3 Detached Code #3 Void Code #2 Crack

22. Visual Assessment Overall Average Ratings

24. Original Dye Tests

25. Maximum Dye Depth (1-hr or 24-hr) Cement-Sand – Best performance overall Neat Cement – Neat1 = 7 gallons and Neat2 = 6 gallons Original Dye Tests Comparison of Cement-Based Grouts

26. Visual Ranking – Performance Ranking = Ranking Variation + Variation = Grout performed better than it appeared – Variation = Grout performed worse than it appeared Grout Type Performance Visual Variation Cement-Sand 1 3.5 +2.5 Chip(3 Wells) 2 1 -1 Neat Cement-7 gal 3 5.5 +2.5 Concrete 4 8 +4 Neat Cement- 6 gal 5 2 -3 Cement-Bentonite 6 3.5 -2.5 Bentonite Slurry >20% 7 5.5 -1.5 Geothermal-Sand ~60% 8 10 +2 Bentonite Slurry =20% 9 7 -2 Geothermal ~20% 10 11 +1 Bentonite Slurry <20% 11 9 -2 Grout Nature and Performance

27. Infiltration into Filter Pack Hydrostatic Head Water Phase Given Off H2O Acidic & High Ca = Breaks Down Chip Recommend blotter sand between materials Neat Cement Grouts

28. Neat Cement Penetrates Bentonite Chips

29. Hydrogeologic Conditions Bentonite slurry grouts appear to be reactive to conditions in the unsaturated zone 2005 Unsaturated Zone Study by Myers Particle Size Moisture Content Annual precipitation Key Components - Critical Findings

30. Vadose Zone Study 2008-2009

31. Planning began in 2007 Used preliminary findings from the original grout study (2001-2006) Each group of the expanded technical team was to develop annular fill mixes that had not been previously tested. Attempt to test as many variations as possible that would resist cracking, be easily placed, economical, and readily available Annular Fill Mix Design

32. Drill Method – Rotary Placement –Predominately Freefall from surface, some tremie State Mixes Mix #1Mix #2 Mix #3 10 gallons water Drill cuttings 1 bag cement Puddled clay Gravel pack – 100 lbs sand topped with 5 lbs bentonite chips

33. Drill Method – HSA Placement – Predominately Tremie, some free fall Mix #1 Mix #3 14 gal H2O 24 gal H2O 1 bag bentonite 1 bag dispersed bent (one step ) 450 lb sand (16-30) Mix #2 Mix #4 18 gal H2O 1 part 30 mesh bent granular 1 bag bentonite 3 part masonry sand 16-30 2.5 lb catalyst Environmental Mixes

34. Drill Method – Rotary Placement – Predominately Tremie, some free fall… Mix #1 Mix #3 22 gal H2O 1 part chip bent 1 bag bentonite 3 part pea gravel 400 lb sand(30-70) Mix #3 18 gal H2O 1- 94 lb cement 50 lb bentonite Wyo-Ben Mixes

35. Drill Method – Rotary Placement – Predominately Tremie some free fall Mix # 1 Mix # 3 36 gal H2O 1 part bentonite 1 bag bentonite 1 part sand (by volume) 50 lb sand 36 oz polymer Mix # 2 10.5 gal H2O 1- bag bentonite Cetco Mixes

36. Drill Method – Rotary Placement – Predominately Tremie, some free fall… Mix #1Mix #2 5.2 gal H2O 1 part granule bent. 1 bag cement 1 part sand 6-9 mesh 2 lb IDP- 381 (by weight) Mix #2 5.2 gal H2O 1 bag cement (pozzolanic additive) Baroid Mix 1

37. Unit Composition 14 gallons water a. untreated b. treated –Soda Ash 1 bag bentonite (200 mesh) Drill Method – Direct Push Placement – Tremie Direct Push Mix 1 a & b

38. Composition sand bentonite drill fluid Drill Method – Rotary Placement – Freefall through the drilling fluid Geothermal Loops 1

42. HSA - All Mixes – Match Grout to Environment Dry Borehole Use Dry Mix? High Water High Solids

43. Direct Push

45. Rotary – All Mixes High Water Content High Solids Content

47. “The borehole cannot be sealed”…Dave Hansen Design Water Technology- 2001 Because the surrounding unsaturated zone isn’t sealed… The unsaturated zone acts as filtration for ground water re-charge… The protection of groundwater depends upon the protection of the filtration system… And includes the reconstruction of conditions in the borehole that mirror the surrounding soils in the unsaturated zone Unconventional Thinking – New Results

48. Better understanding of the unsaturated zone physical properties More attention to unsaturated zone geology while drilling the borehole More accurate detail of the borehole recorded on well logs Logging every change no matter where it occurs Know the descriptive language for identifying formations Matching the grout composition to the on-site conditions Unconsolidated vs. Consolidated unsaturated zones What is Needed?

49. “There is no magic bullet”… Grout must maintain a less permeable seal than the surrounding vadose zone material… No short cuts… Good grout begins with good samples…obtaining good samples dependant on drilling fluids program… The higher the solids content of the grout column-the better chance your grout has of maintaining protection of the ground water… What is the best method?...Best Material?

50. Bentonite slurries perform when they stay wet… Sand added to bentonite slurries improves performance… Bentonite slurries will not re-hydrate once damaged… Bentonite chips perform very well in the saturated and unsaturated zone–but can be hard to place in a deep settings with narrow annular space… Cement grouts crack above and below static water levels… Cement grouts provide structural stability to the casing in the borehole… Cement grout will not bond to plastic PVC pipe… Cement will intrude through bentonite chips…sand blotter is needed. In Summary- new truths