April 13, 2015 3:00 P.M.
Today, Bill Mauro, Minister of Natural Resources and Forestry, issued the following statement on high-volume hydraulic fracturing (fracking) in Ontario:
“Protecting our environment and water is a top priority for our government.
There are currently no applications before the Ministry requesting approval to explore for shale gas or oil, or to use high-volume hydraulic fracturing, commonly known as fracking.
At this time, the Ministry would not consider applications for the use of high-volume hydraulic fracturing before proper consultations with stakeholders, Aboriginal communities, and the public are conducted to ensure that adequate measures are in place to protect the environment.
Staff from my ministry, and the Ministry of the Environment and Climate Change, will continue to monitor the latest developments and research in other jurisdictions.”
Some of the oil and gas wells currently in Ontario, including horizontals:
Ontario has “~3,600 records” for “Well treatments and stimulations. Includes details on the treatment type, treatment pressure, treatment volume, depth interval, and formation.”
Future exploration and development of Ontario natural gas and oil reservoirs will require hydraulic fracturing to make the production economic.
In most wells drilled in Ontario to depths below 500m….
An operator may choose to intersect the target conventional oil or natural gas zone using a horizontal wellbore to expose more reservoir rock. To date in Ontario, no high volume hydraulic fracturing has been used to stimulate these conventional horizontal wells [But, the Ministry has not yet defined “high volume” so who knows what companies are doing? More below]
The oil or natural gas zone is then perforated by “shooting” small holes through the casing and is stimulated through the perforations to allow the fracture fluids and particles to enter only in the desired area (see Diagram 3). This practice is standard oilfield activity in Ontario.
In Ontario, fracturing stimulations are necessary for the economical production of oil and natural as from Paleozoic-age (525 to 360 million years old) conventional reservoir rocks that have low porosity and permeability, low natural flow, compared to very porous and permeable young rocks (120 to 60 million years old, e.g., Gulf Coast USA) with high natural flow characteristics.
The amount of fluid pumped to qualify as a high volume hydraulic fracture treatment varies by jurisdiction throughout North America.
In Ontario a defined fluid volume necessary to qualify as a high volume hydraulic fracture treatment has not been established as it has yet to be determined if production from shale formations can be done economically. [ISN’T THAT A VICTIM-LIKE WAY TO RUN AN ENERGY MINISTRY? WHO’S IN CHARGE? INDUSTRY OR THE MINISTRY?] The fluid volumes that may be required will depend on the depth of the shale zones and the number and size of each hydraulic fracture treatment pumped along the multi-staged horizontal length of the well in Ontario.
Currently, wells drilled in Ontario use less than 5% of the water volume used in other jurisdictions for higher volume multi-stage hydraulic fracture treatments.
The Ontario oil and natural gas industry is dependent on hydraulic fracture stimulations to continue the exploration and development of conventional oil and natural gas reservoirs. Approximately 3,500 hydraulic fracture treatments have been performed in Ontario since the 1950’s without incident or any impact to the environment. In Ontario the volume of fluids used in hydraulic fracture treatments has ranged up to 360 m3 (79,000 gallons). [Emphasis added]
[Interesting how much less industry and regulators used to lie about movement of injected fluids, including into drinking water zones:
Subsurface Injection in Ontario, Canada by Robert T. Kent, Daniel R. Brown, and Michael E. Bentley, Underground Resource Management, Inc., Austin, Texas, USA and Ontario Ministry of the Environment, London, Ontario, Canada [Date not specified, but most recent reference included in the paper was 1982]
Underground injection has been used in Ontario for decades to dispose of brackish waters and brines that are produced from oil and gas wells. The first injection well for liquid industrial waste was completed near Sarnia in 1958. In the next few years, a number of additional industrial injection wells were drilled near Sarnia. The majority of the wells were completed in the Detroit River Formation at depths generally less than 1,000 feet (304m). This area was the site of intensive exploration for gas in the overlying Dundee Formation, and many cabletool holes had been drilled to the top of the Detroit River Formation early in this century. In the late 1960’s, several events occurred where industrial waste and/or brine flowed to the land surface through abandoned and inadequately plugged boreholes. As a result of these problems, industries in the Sarnia area voluntarily decreased their injection rate.
Ultimately, regulations were passed which prohibited industrial waste injection into the Detroit River Formation.
Since December 31, 1976, only brine has been injected into the Detroit River Formation. …
… The most commonly utilized alternative to injection has historically been by discharge to surface waters or by disposal in “evaporation” pits, which has frequently resulted in contamination of shallow ground waterand is now prohibited in many areas. Surface storage and discharge to surface waters have been common in Southwestern Ontario, but are now discouraged where an air or water pollution potential exists.
The first industrial disposal wells in Ontario were completed by Imperial Oil Limited at Sarnia between 1958 and 1960. Five disposal wells and one observation well were drilled on refinery property. In the next few years, a number of additional disposal wells were drilled by other industries in the Sarnia area. Most of the wells were completed in the Detroit River Group of Formations, at depths of 600 to 900 feet (182 to 273m). A total of 18 industrial waste injection wells were operated in the Lambton County area during the period from 1958 to 1974. All but two wells were completed in the Detroit River Group. The other two injected into a leached salt cavern. During the period from 1958 to 1974, over 63,717,330 BBLS (10,131,055 m3) of industrial waste were injected into the Detroit River Group. …
Oil Field Waste
… It is desirable to locate disposal facilities as close as possible to the industries they serve. Besides the economy of short transport distances, the installation of remote disposal sites or pipelines may involve difficulties in obtaining local permits or rezoning of property. Unfortunately, the properties of the disposal formations are different in different areas, and injection may not be geologically feasible at the site where it is most needed.
Sixteen wells were reportedly used for oil field brine disposal into the Detroit River Group and seven for disposal into the deeper Guelph Formation between 1970 and 1981. Some were used continuously through that period. Records of the MNR indicate that four new brine disposal wells were completed in 1981. If oil and gas production rates do not change significantly, then the amount of brine wastes injected into the Detroit River Group in the future should be similar to past amounts.
Environmental Problems of Waste Injection
In the late 1960’s, several incidents occurred where industrial waste or brine flowed to the land surface through abandoned and inadequately plugged boreholes. In 1966, high-pH phenolic wastes emerged beneath a building on the property of Imperial Oil Enterprises Limited in Sarnia. An old borehole was located and plugged. In 1967, another well on the property of Imperial Oil began to flow. The well was found to be obstructed at a depth of 190 feet and was plugged. In 1967, eleven old wells in Port Huron, Michigan began to flow and were subsequently plugged. Soon afterwards, several other wells began to 1 eak. One sample of the water was analyzed by Michigan authorities and was reported to contain 15 ppm of phenol, 820 ppm of H2S, and a pH of 8.7. Previous samples of native waters from the Detroit River Group reportedly had not detected phenols or H2S.
The breakout problems were reviewed by the Ministry of Mines and Northern Affairs in 1970, with the assistance of the staff of the Ontario Water Resources Commission. This review resulted in a notice to industry that wells utilizing the Detroit River Group were to be phased out within two years in the area along the St. Clair River, that the volume of waste injected in this area should be voluntarily reduced, that research into alternate methods of disposal should be accelerated….
The Lucas Formation of the Detroit River Group is the most important zone used for injections in Ontario. The Lucas Formation consists principally of dolostone and limestone, though the section is relatively complex and contains a number of different lithologies. Evaporitic beds become thicker and more numerous toward the center of the Michigan Basin, where an aggregate thickness of 1,000 feet (304 m) of halite and anhydrite occurs (Briggs, 1959). In some areas, anhydrite beds have reportedly been dissolved by natural processes, creating vuggy or cavernous “lost circulation” zones of high permeability. The Lucas formation occurs at a depth of approximately 600 feet (183m) at Sarnia.
The Dundee Formation overlies the Detroit River Group. The Dundee is a fine-grained limestone that contains scattered chert nodules. A lenticular zone of high porosity dolostone (“lost circulation zone”) occurs near the base of the Dundee. The Dundee is approximately 160 feet (50 m) thick near Sarnia. The Dundee is overlain by the Hamilton Formation, which is a calcareous shale and limestone; the upper part is a limestone interbedded with calcareous shale. The thickness of the Hamilton in southwestern Ontario varies from about 150 feet (45 m) in the south to 650 feet (198m) to the north. The Kettle Point Formation unconformably overlies the Hamilton and forms the bedrock throughout much of Kent and Lambton counties. The Kettle Point is a thin-bedded dark shale and attains a maximum thickness of 200 to 300 feet (61 to 91 m) in eastern Michigan.
The Port Lambton is the youngest Paleozoic formation in southwestern Ontario. It occurs in a small area in the vicinity of Mooretown and Sambra along the St. Clair River. The Port Lambton is composed of shale with minor sandstone and siltstone.
Injection of waste liquids into the subsurface should be permitted only in cases where it can be assured that resources such as fresh water, oil and gas, and other subsurface resources can be protected. Protection of these resources requires knowledge of their location and adequate hydrogeologic study of the reservoir strata.
Many communities in southwestern Ontario rely on abundant surface water resources. However, in rural areas, the most accessible supply of water is shallow ground water in the glacial deposits or in the upper part of underlying bedrock deposits.
The glacial deposits in Lambton County are underlain by shale of the Kettle Point Formation and by shale and limestone of the Hamilton Formation. About 90% of the water wells in L ambton County obtain water from the sand and gravel near the top of the bedrock. The thickness and grain size of these deposits determine the productivity of wells. The bedrock surface in Lambton County slopes toward the St. Clair River. The thickness of the till is approximately 60 to 150 ft. (18 to 45 m) (OWRC, 1969). Water level data suggest that water moves from east to west toward the St. Clair River and Lake Huron, in the direction of the slope of both the land surface and the bedrock surface.
Oil and Gas
The first commercial oil production in Ontario began at Oil Springs in 1857 (Harkness, 1931). The presence of evidence of a former oil spring on the ground surface (“gum beds”) led to drilling in this location and the subsequent discovery of oil in several shallow horizons, including the glacial deposits and a dolomitized zone in the Dundee at a depth of 360 ft. (110 m).
Many thousands of exploratory holes were drilled in Lambton County in the late 1800’s and early 1900’s in search of oil and gas in the Dundee Formation. Most of the records of wells drilled prior to 1930 no longer exist and the locations and plugging status of most of them are unknown. These artificial penetrations of the confining beds allowed the breakout of injected waste in western Lambton County in the 1960’s.
Operators are now required by the Ministry of Natural Resources (MNR) to submit an application for a permit to drill or deepen oil and gas wells and, upon completion of drilling, are required to submit a well history summary card and cuttings samples taken at 10-foot (3 m) intervals. These records have been combined with older data to form a computerized geologic information system known as the Ontario Well Data File. When a well is abandoned, it must be plugged according to MNR regulations.
Evaluation of Waste Injection
The environmental implications of disposal of brines to the Detroit River Group of Formations can be determined by subdividing the potential impacts into two classes.
The first class consists of those processes that may result in local escape of injected fluid or poor-quality native brines from the disposal formation during the operating life of a well. This may result from failure of the well itself, or failure of the geologic media to contain the wastes, during the period when fluid pressures in the receiving formation are increased due to injection.
The second class of potential concern is the fate of the slug of injected fluid after the well has ceased to operate. When the increased pressure due to injection dissipates, movement of the slug will be influenced by natural, regional circulation in the sedimentary basin. It would be desirable to estimate flow rates and the locations of regional discharge zones. Desirable properties of the regional system include slow rate of migration, large degree of dispersion and dilution, and low-flux discharge.
The scope of this paper is primarly concerned with the short term, local effects of injection.
Containment of Waste
Upward movement of waste or poor-quality native water out of a disposal zone is more likely to occur in the area relatively near the well than at great distances, since the imposed increase in hydraulic head is greatest at the well. Injection wells should be engineered and the site selected to ensure that the well structure is competent and that the confining beds have sufficiently low permeability and high integrity within the area of increased heads so that upward escape is unlikely. The nature of the porosity of the disposal reservoir will determine the extent and shape of the area of greatest concern, where pressures are above some critical level.
It has been estimated (Mclean, 1968) that about 10,000 wells drilled in southwestern Ontario and eastern Michigan before and around the turn of the century were never properly plugged and the records have been lost, hence the locations of these wells are unknown.
Although the concept of area of influence is attractive because it is technically sound, in practice it is not always applicable because the native head in the injection zone may be equal to or greater than the head in the zone of fresh water. In this case, the concept of a distance from the well where the heads are equal or where the head in the injection zone is lower than that in the overlying aquifer has no meaning. …
Unfortunately, the existence of a large number of unrecorded and unplugged exploratory boreholes in some areas may make this calculation irrelevant in the context of defining the area within which wells are to be plugged.
An area of review can be calculated, but the records or location of all boreholes within this area cannot be obtained. It is apparent, then, that the radius of endangering influence would have to be reduced to zero, by keeping operating liquid levels low, in order to completely eliminate the risk of movement of undesirable fluids into the overlying
fresh water. Well testing followed by calculation of the geographic extent of the theoretical zone of “endangering influence,” which has not been done in the past, would aid greatly in determining the relative risks of allowing heads in the disposal zone to rise to various levels
above heads in the freshwater zone, assuming that the locations of abandoned wells are scattered randomly throughout the region.
The route of pressurized fluids from an injection well to a water well consists of several links. The water must first travel through the disposal zone to a point of weakness or conduit in the confining beds such as a fracture or abandoned, unplugged borehole. If a vertical conduit exists through the confining beds and the conduit intersects a high-permeability disposal zone near the injection well, the pressure increase in the conduit may be large enough to cause upward migration of waste or native fluids. (The pressure “front” extends farther from the well than the waste ”front.”) Cross-formational flow can occur if the conduit has an outlet to a permeable stratum with lower hydraulic head. The fluid could also pass through an “intermediate” reservoir by discharging from a conduit into a porous and permeable lens in the confining beds, and then into a second conduit that penetrates the lens.
An outlet from a conduit to the land surface or to the freshwater zone in the glacial deposits or in the upper bedrock is the most undesirable situation and represents the primary failure scenario leading to environmental impairment. Unfortunately, the presence or absence of unplugged holes or moderately permeable fractures that penetrate the disposal zone cannot be unambiguously determined from hydraulic well tests and/or detailed geologic mapping.
Flow of waste or formation brine to the land surface may be readily observed, but flow into a freshwater aquifer may go undetected for years or decades, due to the slow rate of migration through granular deposits and the low density of wells which can be sampled to detect the foreign waters. It is not economically feasible to install an extensive array of monitor wells for the purpose of rapidly detecting the arrival of contaminants in glacial aquifers if the area to be monitored is large. However, nearby municipal and domestic wells can be sampled regularly in order to protect these users. Wells that have high average production rate should be included in a freshwater monitoring program because they sample a relatively larger part of the aquifer. Also, since the greatest pressure increase in the injection zone is near the injection well, a shallow well completed in the freshwater aquifer could be installed at the disposal site in order to provide monitoring where the driving force is highest.
In most injection wells, shallow freshwater resources are protected from the elevated fluid pressures in the reservoir near the well by intervening low-permeability confining beds. This technique cannot be relied upon in southwestern Ontario due to the large number of undocumented abandoned boreholes.
The suggested regulatory procedure would require more detailed information to be gathered by the applicant than was previously necessary. This would be unnecessary if the applicant agrees to operate at a very low pressure or fluid level that was based on expectation of worst-case conditions. If the applicant desires to operate at the maximum prudent level, he would accept the responsibility for determination of the properties of the disposal zone necessary to properly evaluate the area of endangering influence of his well. [Emphasis added]
[Refer also to:
2015 04 12: Fracing Rerun in New Brunswick Government. Why? Did Jason Kenny and Senior Alberta Government Advisor, frac patent holder Dr. Maurice Dusseault complain that citizens aren’t brainwashed yet like they are in Alberta? ]