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Dams and Impoundments

Dams and Impoundments. 2010 Industry Training Workshop Jim Kline DEP- Bureau of Oil and Gas Management. Objectives:. Typical Scenarios Worksheet for Permitting of Marcellus Shale Pits and Dams What permits (if any) might be needed Construction Standards for Impoundments

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Dams and Impoundments

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  1. Dams and Impoundments 2010 Industry Training Workshop Jim Kline DEP- Bureau of Oil and Gas Management

  2. Objectives: • Typical Scenarios • Worksheet for Permitting of Marcellus Shale Pits and Dams • What permits (if any) might be needed • Construction Standards for Impoundments • Groundwater Monitoring • Current impoundment trends

  3. Typical Scenarios • Dams on a watercourse • Dams not on a watercourse • Dams on awatercourse

  4. Dams on a Watercourse Greater than 100 acre drainage area, OR Greater than 15’ maximum depth, OR Greater than 50 acre-feet maximum storage

  5. Drainage area The drainage area is the total surface area upstream of a point on a stream, where the water from rain or snowmelt which is not absorbed into the ground flows over the ground surface back into the stream to finally reach that point on the stream.

  6. Drainage area

  7. What the heck is an Acre Foot? A measurement associated with a larger volume, in this case water storage. It is the amount of water required to cover an acre one foot deep. An acre foot is equivalent to 325,851 gallons of water 50 acre feet is equal to 16,292,550 gallons of water

  8. MAXIMUM DEPTH Dmax > 15 ft

  9. The bottom of the Pit or Impoundment must be constructed at least 20” above the seasonal high groundwater table.(ref Ch 78.56 (a) (4) (iii))

  10. Dams on a Watercourse Greater than 100 acre drainage area OR Greater than 15’ maximum depth OR Greater than 50 acre-feet maximum storage If this is the scenario, then a Dam Safety Permit is required from DEP’s Division of Dam Safety

  11. Dams not on a watercourse Greater than 15’ maximum depth AND Greater than 50 acre-feet maximum storage

  12. Worksheet for Permitting of Marcellus Shale Pits and Dams

  13. Worksheet for Permitting of Marcellus Shale Pits and Dams 1. Fresh or frac water impoundment pits or dams at a well location must meet the requirements of PA Code Chapter 78.56 – 78.63 and the Design,Construction and Maintenance Standards for Pits and Dam Embankments Associated with Impoundments for Oil and Gas Wells. Plans must include an acknowledgement that these pits and impoundment dams will meet the standards. Proceed to Section6 and Section 8 and submit to the appropriate Department Regional Oil and Gas Program Office.

  14. Worksheet for Permitting of Marcellus Shale Pits and Dams • 2. On-stream intake dams. (Dams/weirs constructed for water withdrawal from streams. Height and storage are typically minimal.) • 2.A A dam/weir will be constructed on-stream solely for the purpose of water withdrawals: • No:Proceed to Section 3 or Section 4 as appropriate. • Yes: Answer the following questions:

  15. Worksheet for Permitting of Marcellus Shale Pits and Dams • Is maximum depth greater than 15 feet? Yes No • Is maximum storage volume greater than 50 acre-feet? Yes No • Is contributory drainage area greater than 100 acres? Yes No • If the answer to all three of these questions is no, an Environmental Assessment approval is required from the Department’s Dam Safety Program. Please submit form 3140-PM-WE0002, Environmental Assessment Information Sheet and information required on that form’s checklist to the Department’s Dam Safety Office. Any excavation of the stream, wetland or floodway upstream of this intake dam to expand storage volume will require a Water Obstruction and Encroachment Permit from the appropriate Department Regional Office.

  16. Worksheet for Permitting of Marcellus Shale Pits and Dams • If the answer to any one of these questions is yes, a Dam Permit may be required from the Department’s Dam Safety Program. Answer the following questions: • Is height of dam/weir above streambed elevation greater than 3.0 feet? Yes No • Is width of stream at the dam site greater than 50 feet? Yes No • Is this stream a wild trout stream designated by the PA Fish and Boat Commission? Yes No

  17. Worksheet for Permitting of Marcellus Shale Pits and Dams • If the answer to all three of these questions is no, the Dam Permit for this dam is waived pursuant to §105.12(a)(1) of the Department’s regulations. Contact the Department’s Dam Safety Program for information requirements necessary for adding to Pennsylvania’s Dam Inventory. • If the answer to any one of these questions is yes, a Dam Permit is required from the Department’s Dam Safety Program. Please complete form 3140-PM-WE0001, “Application for a Dam Permit”, and information required on that form’s checklist to the Department’s Dam Safety Office. Utilize the Design,Construction and Maintenance Standards for Pits and Dam Embankments Associated with Impoundments for Oil and Gas Wells to develop plans and specifications.

  18. Worksheet for Permitting of Marcellus Shale Pits and Dams • 3.Centralized fresh water impoundments. • 3.AA dam embankment will be constructed for the purpose of storing fresh water for the drilling or fracing at more than one well location: • No: Fresh water will be impounded in a pit. Proceed to Section 7for additional information requirements. • Yes: Provide the following depth and volume information and proceed to Section 3.B.

  19. Worksheet for Permitting of Marcellus Shale Pits and Dams • Maximum depth of water that could be impounded by the earthfill dam. See Exhibit 1. Feet. (Measure from the inside toe-of-slope of dam to top-of-dam embankment). • Maximum storage volume of water that could be impounded by the earthfill dam. See Exhibit 1. acre-feet (Measure from the inside toe-of-slope of dam to top-of-dam embankment). • Drainage area to the earthfill dam, if located on-stream, then proceed to Section3.B. Acres. • If located off-stream, proceed to Section3.C.

  20. Worksheet for Permitting of Marcellus Shale Pits and Dams • 3.B If the dam embankment used to impound fresh water is located on a watercourse, complete the following: • Is maximum depth greater than 15 feet? Yes No • Is maximum storage volume greater than 50 acre-feet? Yes No • Is contributory drainage area greater than 100 acres? Yes No

  21. Worksheet for Permitting of Marcellus Shale Pits and Dams • If the answer to any one of these questions is yes, a Dam Permit is required from the Department’s Dam Safety Program. Please submit form 3140-PM-WE0001, “Application for a Dam Permit”, and information required on that form’s checklist to the Department’s Dam Safety Office.

  22. Worksheet for Permitting of Marcellus Shale Pits and Dams • If the answer to all three of these questions is no, an Environmental Assessment approval is required from the Department’s Dam Safety Program. Please submit form 3140-PM-WE002, Environmental Assessment Information and information required on that form’s checklist to the Department’s Dam Safety Office. Any excavation of the stream, wetland or floodway upstream of this intake dam to expand storage volume will require a Water Obstruction and Encroachment Permit from the appropriate Department Regional Office.

  23. Worksheet for Permitting of Marcellus Shale Pits and Dams • 3.C If the dam embankment used to impound fresh water is notlocated on a watercourse, complete the following: • Is the dam located in a FEMA (Federal Emergency Management Agency) designated floodway? Yes No • If the answer is yes, a Dam Permit may be required from the Department’s Dam Safety Program and/or a restudy of the FEMA Floodway may be required to assess the impacts of the dam on the floodway. Coordination will also be required with the local municipality to assure that they remain eligible for the National Flood Insurance Program. Please submit information required in Section 6 to the Department’s Dam Safety Office for the determination of the need for a permit or other approvals.

  24. Worksheet for Permitting of Marcellus Shale Pits and Dams • If this answer is no, continue with the following questions: • Is maximum depth greater than 15 feet? Yes No • Is maximum storage volume greater than 50 acre-feet? Yes No • If the answer to both of these questions is yes, a Dam Permit is required from the Department’s Dam Safety Program. Please submit form 3140-PM-WE0001, “Application for a Dam Permit”, and information required on that form’s checklist to the Department’s Dam Safety Office.

  25. Worksheet for Permitting of Marcellus Shale Pits and Dams • If the answer to either or both of the above questions is no and the dam directly impacts a wetland, an Environmental Assessment approval is required from the Department’s Dam Safety Program. Please submit form 3140-PM-WE0002 Environmental Assessment Information Sheet and information required on that form’s checklist to the Department’s Dam Safety Office. Utilize the Design,Construction and Maintenance Standards for Pits and Dam Embankments Associated with Impoundments for Oil and Gas Wells to develop plans and specifications. • If the answer to either or both of the above questions is no and the dam does not impact a wetland, no dam permit is required.

  26. Worksheet for Permitting of Marcellus Shale Pits and Dams • 4. Centralized frac water storage (Fluids other than fresh water (e.g. drilling or fracing fluids)): 4.A If a dam embankment will be constructed to create this storage facility, proceed to Section 4.B. • If the storage facility is to be an excavated lined pit, the facility must meet the requirements of PA Code Chapter 78.56 – 78.63 and the Design,Construction and Maintenance Standards for Pits and Dam Embankments Associated with Impoundments for Oil and Gas Wells. Plans must include an acknowledgement that this pit will meet the standards. Complete information requirements in Section 6 and Section 8 and submit to the appropriate Department Regional Oil and Gas Program Office.

  27. Worksheet for Permitting of Marcellus Shale Pits and Dams • 4.B A dam embankment will be constructed to impound frac water and the following describes this impoundment: • Length ft. • Width ft. • Maximum potential depth of frac water ft. • Storage Volume ____ ac.-ft.

  28. Worksheet for Permitting of Marcellus Shale Pits and Dams • 4.CThis dam embankment to be constructed to impound frac water is: (Please check appropriate box below) • a. Located on a watercourse. • b. Located off-stream, but impacts a wetland. • c. Located off-stream and in FEMA (Federal Emergency Management Agency) Floodway. • d. Located off-stream, storage volume exceeds 50 acre feet and depth of impoundment exceeds 15 feet as noted in 4.B above. • e. Located off-stream, storage volume is less than 50 acre feet or depth of impoundment is less than 15 feet as noted in 4.B above.

  29. Worksheet for Permitting of Marcellus Shale Pits and Dams • If any of the boxes a through d are checked, a Dam Permit is required from the Department’s Dam Safety Program. Please submit Form 3140-PM-WE0001, “Application for a Dam Permit”, and information required on that form’s checklist to the Department’s Dam Safety Office. Also, submit information requirements in Section 8. Utilize the Design,Construction and Maintenance Standards for Pits and Dam Embankments Associated with Impoundments for Oil and Gas Wells to develop plans and specifications. • If box e, is checked, proceed to Section5.

  30. Worksheet for Permitting of Marcellus Shale Pits and Dams • 5. Potential Impacts of Dam Failure Failure of this frac water impoundment dam has the potential to: • Impact inhabited structures: Yes No • Cause significant property damage: Yes No • Flood roadways: Yes No

  31. Worksheet for Permitting of Marcellus Shale Pits and Dams • If yes to any of the dam failure impact questions, a Dam Permit is required from the Department’s Dam Safety Program. Please submit Form 3140-PM-WE0001, “Application for a Dam Permit”, and information required on that form’s checklist to the Department’s Dam Safety Office. Also, submit information requirements in Section 8. Utilize the Design,Construction and Maintenance Standards for Pits and Dam Embankments Associated with Impoundments for Oil and Gas Wells to develop plans and specifications.

  32. Worksheet for Permitting of Marcellus Shale Pits and Dams • If no to all of the questions above, a Dam Permit from the Department’s Regional Bureau of Oil and Gas Management office is required. Please submit form 5500-PM-OG0084, “Application For ADam Permit For A Centralized Impoundment Dam for Marcellus Shale Gas Wells”, and information required on that form’s checklist to the Department’s Regional Bureau of Oil and Gas Management Office.Also, complete information requirements in Section 8. Utilize the Design,Construction and Maintenance Standards for Pits and Dam Embankments Associated with Impoundments for Oil and Gas Wells to develop plans and specifications.

  33. Worksheet for Permitting of Marcellus Shale Pits and Dams • 6. Attach a copy of USGS 7½ minute quadrangle map showing the location of the pit or dam and attach a site plan and typical cross-sections of the pit or dam.

  34. Worksheet for Permitting of Marcellus Shale Pits and Dams 7. If a pit is proposed to store fresh water, no Dam Permit is required. However, if the pit is located on a watercourse, in the floodway of a watercourse, or in a wetland, a Water Obstruction and Encroachments Permit is required. Please submit Form 3930-PM-WE0036 Joint Permit Application and information on that form’s checklist to the Department’s appropriate Regional Office, Permitting and Technical Services Section. 8. Attach site restoration plan for all frac water impoundment pits and dams. Frac water impoundments pits or dam sites must be restored within nine months after completion of the last well that was serviced by the impoundment.

  35. Centralized Impoundments

  36. Well Site Pits and Impoundments • Pits and impoundments located on the drilling site will be authorized by the Oil and Gas Well Permit. These impoundments must follow the Construction Standards.

  37. Construction Standards for Dams and Embankments Associated with Pits and Impoundments for Oil and Gas Wells

  38. Construction Standards The operator may use alternate construction standards if they meet or exceed the Department’s Construction Standards, if they are developed, sealed and certified by a professional engineer registered in Pennsylvania; and if they are approved through a Dam P Application process through the Department’s Division of Dam Safety prior to commencement of construction.

  39. Construction Standards • Soils to be used for dam embankment construction must be classified in accordance with ASTMD-2487 (Unified Soils Classification). A minimum of three samples must be classified. • Soils acceptable for dam embankment construction are limited to GC, GM, SC, SM, CL or ML. Soils must contain a minimum of 20% of Plus No. 200 sieve materials.

  40. Gradation Sheet GC- Clayey gravels GM- Silty gravels SC- Clayey sands SM- Silty sands CL- Inorganic clays low to medium plasticity ML- Inorganic silts and fine sand, slight plasticity

  41. Site Preparation • Foundation of dam embankment must be stripped and grubbed to a depth of two feet prior to any placement & compaction of earthfill. • Any springs encountered in the foundation area should be drained to the outside/downstream toe of the embankment with a drain section two foot by two foot in dimension consisting of PennDOT Type A sand, compacted by hand tamper. No geotextiles to be used around sand. The last three feet of this drain at the outside/downstream slope should be AASHTO #8 material.

  42. Compaction • All compaction for embankments must be done with a sheepsfoot or pad roller. • Loose lift thickness must be 9” or less. • Maximum particle size is 6”. • A minimum of 5 passes of the compaction equipment over the entire surface of each lift is required. • Compaction to visible non-movement of the embankment material is required.

  43. Soil Placement and Compaction

  44. Pad Rollers

  45. Design Criteria • Minimum embankment top width of 12’ is required. • Minimum inside & outside sideslopes of 3H:1V are required. • All exposed embankment slopes must be limed, fertilized, seeded and mulched. Permanent vegetative ground covering compliance with PA Code Chapter 102.22 must be established upon completion of dam construction. • 2’ of lined freeboard must be maintained at all times.

  46. Embankment Top Width Minimum 12’

  47. Take a closer look…..

  48. Failure to properly compactmovement of the embankment material

  49. Failure to maintain 2 feet of lined freeboard

  50. Selecting the Correct Liner

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