Part 7. Oil Field Fluid Disposal Wells

No person shall commence disposal operations without written approval from the Ministry.

Operators shall design, construct, operate and maintain oil field fluid disposal wells to:

  1. permanently isolate and protect all potable water formations from contamination;
  2. protect existing and potential hydrocarbon-bearing formations from contamination caused by migration of the injected fluid;
  3. prevent the migration of fluids between permeable formations;
  4. ensure that the disposal fluids are compatible with the disposal formation such that precipitates or clay mobilization are minimized; and
  5. ensure that the disposal fluids are retained within the disposal formation.

Note: A typical disposal well design is shown in Figure 3.

7.01 Restricted disposal areas

Disposal into the Detroit River formation in areas located within 8 km of the St. Clair River is prohibited.

7.1 Notification

An operator planning to dispose of oil field fluid shall notify in writing:

  1. all landowners and other operators located within 750 metres of the proposed well site;
  2. the municipality in which the disposal well is situated; and
  3. the Ministry.

7.2 Disposal well design and construction

The operator shall design and construct a disposal well to include:

  1. injection of oil field fluid through tubing:
  2. isolation of the annular space between the tubing and production casing from the injection zone by a packer or some other acceptable method;
  3. placement of a corrosion inhibitor within the annulus outside the injection tubing;
  4. isolation of all fresh water zones with casing and cement;
  5. cementing the surface casing, intermediate and product casings to surface; and
  6. wellhead components that are rated to 110 percent of the maximum operating pressure.

7.3 Formation water sampling

The operator shall collect and analyze samples of water from each aquifer penetrated during the drilling of the disposal well, and:

  1. record the depth, chemical characteristics and static level of each aquifer; and
  2. provide a copy of the chemical analysis of each formation water to the Ministry.

7.4 Existing well conversions

Conversion of existing wells for use as disposal wells may be made if:

  1. the well’s condition and construction meets the requirements of this Standard; and
  2. for conversion of a well older than 10 years, the operator conducts additional pressure tests, casing evaluation logs and cement evaluation logs to demonstrate the integrity of the well’s casing and the cement seal.

7.4.1 Old wells

Wells that are 20 years and older shall not be converted for use as a disposal well.

Note: No departures from this requirement will be accepted.

7.5 Disposal report

The operator shall prepare and submit a report to the Ministry on the suitability of the proposed disposal well and formation for oil field fluid disposal and the report shall include:

  1. the name and address of the operator;
  2. the location, identity, status, depth, formation at total depth, the oil, gas, water and loss of circulation zones encountered in wells located within 750 metres of the proposed disposal well;
  3. for wells identified in item (b), that penetrate the disposal formation, the casing, cementing and plugging details of the wells;
  4. the location and status of potable water wells within 750 metres of the proposed disposal well;
  5. a description of all uses of the subsurface within 750 meters of the proposed well;
  6. a chemical analyses of the formation water in the proposed disposal;
  7. the chemical analyses of water samples taken from the fresh water wells or selected representative wells identified in item (d);
  8. the initial reservoir pressure of the disposal zone;
  9. the volume, rate, and maximum injection pressure for the proposed disposal operation;
  10. the source, chemical composition and specific gravity of injected oil field fluid;
  11. results of fluid compatibility tests of the proposed disposal fluid with the formation water located in the disposal zone;
  12. the projected subsurface area of influence of the fluid disposal operation over time;
  13. the geology of the disposal formation, its lateral extent, the nature of the upper and lower confining beds, its reservoir characteristics, and its oil and gas potential;
  14. the results of the injectivity test;
  15. the drilling and completion record including any stimulation and workover of the well;
  16. a complete description of the installation and cementing of the surface, intermediate and production casings;
  17. a complete report on the installation of the injection tubing;
  18. records of the tests of the integrity of the various casings;
  19. the well history, if a conversion of an existing well;
  20. a detailed record and cross-sectional diagram of the method of well completion (well-bore diagram);
  21. a description of the proposed fluid handling procedures;
  22. a site plan of the wellhead and associated facilities; and
  23. if external pressure is necessary for the injection of oil field fluid, an assessment of the impact of the applied pressure on the disposal zone, other formations, and subsurface resources.

7.6 Disposal operations

The operator shall:

  1. only inject oil field fluid (formation water and drilling fluid) into a disposal well that;
    1. is produced by the operator, or
    2. originates from the same field and is delivered by pipeline to the disposal well;
  2. not inject fluids that are classified as "liquid industrial waste" under the Environmental Protection Act, including stimulation fluids, unless the well is licensed by the Ministry of the Environment, Conservation and Parks for that purpose; and
  3. not inject oil field fluid between the outermost casing and the well bore or into the annular space between strings of casing.

7.7 Recommended injection practice

Oil field fluids shall be injected:

  1. by gravity feed with no applied pressure or by the lowest practical pressure not exceeding 75% of the known fracture gradient; and
  2. into suitable formations located as deep as practical.

7.8 Pre-Commissioning

Prior to commencing injection of oil field fluid into a disposal well, other than for the initial injectivity test, the operator shall:

  1. identify all known wells and water wells within 750 metres of the disposal well;
  2. confirmed the integrity of the injection casing of the disposal well by pressure tests and/or cement evaluation logs;
  3. run a cement bond log or equivalent logs to verify the integrity of cement; and
  4. conduct an injectivity test on the candidate disposal zone to supplement existing permeability and porosity data and to determine the quality of any candidate disposal zone;
  5. submit the disposal report required in section 7.5; and
  6. submit an operating procedure for the proposed disposal operations.

7.8.1 Water wells

Prior to commencing injection of oilfield fluid, the operator shall collect water samples from selected, accessible fresh water wells located within 750 metres of the proposed disposal well and obtain chemical analyses of the samples suitable for characterization of the ground water according to the specifications of the Ministry of the Environment, Conservation and Parks and during the collection of the samples, the operator shall obtain from the water well owner the following information about each water well and submit this information to the Ministry with the chemical analyses:

  1. depth of well;
  2. age of well;
  3. volume of water taken from the well; and
  4. static level of the water in the well.

7.9 Initial injection test

The operator shall submit the program for the initial injectivity test of a disposal well to the Ministry prior to the commencement of the test and injection of fluids during the test shall be through tubing set on a packer located as close as practical above the injection zone.

7.9.1 Injection test program

The injectivity test program shall include:

  1. the depths of the injection intervals;
  2. the rates of injection;
  3. injection pressure(s); and
  4. the volume and source of the fluids to be injected.

Note: Sampling of the original formation water is required under section 7.3 and should be done prior to injection of any fluid for testing.

7.9.2 Injection test pressure

During the initial injectivity test, the subsurface pressure at the midpoint of the disposal zone shall not exceed 75% of the formation fracture pressure.

7.9.3 Injection test duration and volume

The initial injectivity test shall not exceed:

  1. 30 days in length; and
  2. 500 m3 in total injected fluid.

7.10 Disposal well operations

The operator shall not commence disposal operations unless written approval is received from the Ministry.

7.10.1 Fluid measurement

The operator shall measure the volume of fluid injected and the injection pressures.

7.10.2 Corrosion blanket

The presence of corrosion inhibiting fluid and the isolation of this fluid from the injected fluid, shall be witnessed and certified by an Examiner using a pressure gauge, visual inspection or equivalent means semi-annually.

7.10.3 Maximum injection pressure

The subsurface pressure at the midpoint of the disposal zone shall not exceed 75% of the formation fracture pressure at that depth during the injection of oil field fluid except during well stimulation.

7.11 Site plans

The operator shall keep and maintain plans and maps of the disposal well and associated storage and collection facilities.

7.12 Spill contingency plan

The operator shall have, at its operations center or office, available at all times, a spill contingency plan in the event of a leak or break in a pipeline, storage tank or wellhead and operations personnel shall be trained and knowledgeable regarding this plan.

7.13 Periodic pressure test

The operator shall conduct a pressure test of the annular space after every 5 years of injection and provide for an Examiner to certify the mechanical integrity of the well at this time.

7.14 Termination of injection

Injection of fluid shall be stopped immediately after loss of fluid or an increase of pressure is detected in the tubing annulus, and shall not resume until the cause is determined and remedy is made.

7.15 Records

The operator shall keep and maintain the following information for each disposal well:

  1. name and location of disposal wells;
  2. monthly and cumulative volume of fluid disposed;
  3. volume of fluid from each source;
  4. the operating range of surface pressures during injection;
  5. maximum surface pressure applied during injection;
  6. name of the formation used for disposal;
  7. the depth interval(s) used for disposal;
  8. records of subsurface pressure measurements, pressure fall-off tests and other reservoir performance or evaluation tests;
  9. copies of chemical analyses from fresh water wells adjacent to the disposal well;
  10. descriptions and results of mechanical integrity tests at the well;
  11. description of workovers, acid treatments, and fracture stimulations conducted during the year; and
  12. the source well name and licence number, chemical characterization and transmittal slips for oil field fluids disposed of in the disposal well.

7.16 Periodic examinations

The operator shall provide for an Examiner to examine disposal well facilities and operations semi-annually and to certify that all disposal well standards are met.