Well Abandonment Presentation West Central Stakeholders Rocky Mountain House. November 19, 2013

Transcription

1 Well Abandonment Presentation West Central Stakeholders Rocky Mountain House November 19, 2013

2 Why are Wells Abandoned? The well has reached the end of its productive life and is no longer economical. No other formations in the well have productive potential. Mineral Rights have expired Abandoned wells are common world wide. As of June 2013, the Alberta Energy Regulator states there are approximately 151,000 abandoned wells in Alberta, representing about 35% of all wells. 2

3 Abandoning Oil and Gas Wells Governed by Alberta Energy Regulator Directive 020: Well Abandonment Licensee of record is responsible for the well integrity forever. Before abandoning a well, the licensee must inform all affected landowners. Licensees are required to test the well to ensure it will not pose any risk to the environment or the public after abandonment. If any issues are found during the testing phase, the licensee must make all necessary modifications according to AER requirements. 3

4 Abandoning Oil and Gas Wells cont d To ensure the safe and effective abandonment of all wells, Talisman follows the AER defined and regulated process as follows: 1. Identification and Creation of a Project Plan. Design an abandonment program that identifies any wellbore integrity issues, all oil or gas formations, all groundwater zones and evaluates the cement in the well. 4

5 Abandoning Oil and Gas Wells cont d 2. Execution and Implementation First step is to clean the inside of the well to remove any oil, water or gas that may cause the casing to corrode or limit the effectiveness of the abandonment cement plugs. Any issues identified with the well are repaired and all porous formations and groundwater zones are isolated from each other with cement. Well is then filled with non-saline water or other noncorrosive fluid and is assessed to ensure the long term integrity of the well. 5

6 Abandoning Oil and Gas Wells cont d 3. Finalization- Surface Abandonment The final step is known as the cut and cap. The well casing is exposed and cut off 1-2 meters below ground level. A vented cap is installed on the casing stub with the well id number welded on the cap. All surface equipment is removed within 12 months of the cut and cap operation. 6

7 Abandoned Wells and Potential Risks The AER and Industry do not anticipate any issues living or working near an abandoned wells given the strict requirements set out in Directive 020. Abandoned wells do not place the environment or public at significant risk, however small leaks are possible. A well leak can be caused by many things, including corrosion, improper abandonment or damage incurred during excavation for the cut and cap. If an abandoned well leaks, regulations require the AER to be notified immediately, followed by application and AER program approval before the well can be re-entered to repair the leak. 7

8 Abandoned Wells and Potential Risks cont d Gas (methane) detection tests are used to identify leaks and are conducted by the licensee with all results reported to the AER. If a gas leak is detected, the licensee must meet with the appropriate landowners to discuss an appropriate course of action. Abandoned wells close to development are governed by Directive 079: Surface Development in Proximity to Abandoned Wells Licensee's are required to test wells for methane anomalies as per Directive 079. Depending on the risk category, it may be tested annually (high), every 3 years (medium) or 10 years (low). 8

9 TALISMAN ENERGY INC. WELLBORE DIAGRAM Typical Cased Hole Well Abandonment 100/ W5/00 Lic. No Lic. Date: mm/dd/yyyy, Spud date: mm/dd/yyyy, Rig release date: mm/dd/yyyy KB elev. = 900 m, Grd Elev = 905 m Vertical Well Casing's cut off 2.0 m below G.L. and capped with steel plates Cement Top outside Surface Casing at Surface Cement Top in Production Casing annulus at Surface Base of Ground Water mkb 200 mm Open Hole Formation Tops Belly River, 1158 mkb Surface Casing: mm, kg/m, J55 from Surface to 650 mkb. Cemented using Class G with returns to surface. Production Casing: mm, kg/m, P110 from Surface to 3100 mkb. Cemented using 1:1:2 + Class G with Cement returns to Surface. Lea Park, 1428 mkb Fresh water Cardium, 1768 mkb Viking, 2066 mkb Nordegg, 2292 mkb Nisku, 2785 mkb Cement Plug mkb Permanent Bridge Plug at 3137 mkb Pressure tested to 7,000 kpa Duvernay perforations mkb Beaverhill Lake 3165 mkb Plug Back TD mkb Total Depth mkb 9

10 TALISMAN ENERGY INC. WELLBORE DIAGRAM Typical Open Hole (D&A) Well Abandonment 100/ W5/00 Lic. No Lic. Date: mm/dd/yyyy, Spud date: mm/dd/yyyy, Rig release date: mm/dd/yyyy KB elev. = 900 m, Grd Elev = 905 m Vertical Well Casing cut off 2.0 m below G.L. and capped with a steel plate Fresh Water Cement Top outside Surface Casing at Surface Base of Ground Water mkb Formation Tops Belly River, 1158 mkb Lea Park, 1428 mkb Cardium, 1768 mkb Cement Plug. Surface Casing: mm, kg/m, J55 from Surface to 650 mkb. Cemented using Class G with returns to surface. Drilling mud Cement Plug. Drilling mud Second White Specs, 1930 mkb Base Fish Scales, 2031 mkb Viking, 2066 mkb Cement Plug. Mannvile, 2104 mkb Glauconite, 2208 mkb Ostracod, 2235 mkb Drilling mud Nordegg, 2292 mkb Banff, 2353 mkb Wabamun, 2545 mkb Nisku, 2785 mkb Ireton, 2845 mkb Duvernay, 3147 mkb Cement Plug. Drilling mud 200 mm Open Hole Cement Plug. Cement Plug. Total Depth mkb 10

11 TALISMAN ENERGY INC. WELLBORE DIAGRAM Typical Cased Hole Well Abandonment Drilled pre / W5/00 Lic. No Lic. Date: 1985, Spud date: 1985, Rig release date: 1985 KB elev. = m, Grd Elev = m Vertical Well Casing cut off 2 m below G.L. and capped with steel plates Surface Casing: mm, kg/m, J55. Landed at 204 mkb. Cemented with 17 tonnes Class G + 3% CaCl2. 3 m3 cement returns at surface. Fresh water BGWP- cemented with 9 tonnes Class G Neat. Cement returns at surface through the Surface Casing vent. Base of Ground Water mkb Cement Retainer set at 305 mkb BGWP perforations mkb Formation Tops Belly River, 802 mkb Cement Top logged at 511 mkb Lea Park, mkb Colorado, mkb Fresh water with 0.5% inhibitor Cardium, mkb Second Specks, mkb 200 mm Open Hole Basal Fish Scales, mkb Cement Plug mkb Viking, 1637 mkb Viking perforations mkb Permanent Bridge Plug at 1640 mkb Pressure tested to 7,000 kpa Production Casing: mm, 25.3 kg/m, AC80 landed at 1679 mkb. Cemented with 36 tonnes 1:1: % D65. Tailed in with 4 tonnes Class G + 0.5% D % D65. Joli Fou, mkb Plug Back TD mkb Total Depth mkb 11

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