|Authors:||Duncan Kenyon, Nikki Way, Andrew Read, Barend Dronkers, Benjamin Israel, Binnu Jeyakumar, Nina Lothian|
|Publish Date:||October 2016|
|PDF Download:||[Landowners' Guide] [Landowners' Primer]|
|Pipelines and Other Infrastructure|
Oil and Gas Operational Impacts,
Conservation and Reclamation
|Abandonment and Reclamation|
|Compensation, Rights, and Hearings|
Flaring and venting from wells, gas plants and other facilities and the associated smoke, odour, and potential exposure to hazardous air pollutants have long been a source of concern for those living and working near oil and gas operations.
There are several types of flaring:
|Background information on flaring is given in Flaring: Questions + Answers.|
Research done by the former Alberta Research Council showed that a flare can release a large number of air pollutants, including unburned hydrocarbons and other harmful substances that result from incomplete combustion. The products of incomplete combustion depend on the constituents in the gas that is burned but can include BTEX aromatics, polycyclic aromatic hydrocarbon compounds and, if the gas is sour, hydrogen sulphide (H2S). When H2S is burned, it produces sulphur dioxide, which is also harmful (see Risks of sour gas).
If problems are occurring with flares, you should first contact the company and make them aware of the situation. You can also call the AER’s emergency and complaint line to register your complaint, asking them to investigate and take action. Signs of problems with flaring include visible black smoke or plumes, frequent or long-lasting flares, continuous flaring for projects that have not been approved for such, or abnormally intense flames. If you experience health issues that seem to be correlated with flaring activity, take detailed notes about flaring activity nearby.
You should document issues, especially if they are ongoing: take photographs of flares and smoke, and keep records of the date, nature of the occurrence and length of time that the problem persists. Be sure to include something in the photograph to provide scale and to identify the location where it was taken — such as the company sign adjacent to the site. Ideally, you should use a camera that includes a date and time stamp on the image. This is especially important in cases where the flaring event may conclude before a field inspector can come to the site to investigate.
|Ensure you document any issue you have with an operation, including the time you spent investigating the problem, associated damages, and other relevant details. See the example in Appendix D at the end of the guide for ideas of what you should document.|
Venting of gases can also pose problems. Venting occurs when solution gases from oil wells, batteries or tanks are released unburned to the air. Some venting may also occur from compressor vents, instrument gas stations, pneumatic devices, dehydrators and storage tanks. This release of unburned hydrocarbons to the atmosphere creates odours and exposure to potentially harmful substances. Vented gas also contributes to global climate change and wastes a non-renewable resource. Current AER regulations set standards for venting and allow venting of small volumes of gas where it is not considered practical to recover or flare it. For example, continuous venting of gas containing H2S must not exceed Alberta Ambient Air Quality Guidelines for H2S or result in odours outside the lease boundary. There are also limits on the total amount of benzene that may legally be released.
|Venting of natural gas or methane from oil and gas operations is a significant contributor to climate change. Methane is 86 times more potent as a greenhouse gas than carbon dioxide, over a 20-year period. The Government of Alberta has announced as part of its Climate Leadership plan that methane emissions will be reduced by 45% below 2014 levels by 2025.|
Flaring and venting can be eliminated in various ways, such as by piping the gases for other processing, using the gas on-site to drive equipment or provide heat, or pooling gas from several small sources and sending via pipeline to processing plants. When deciding about flare reductions, a company must consider economic, social and environmental factors, including the proximity of nearby residents.
While emissions from solution gas flares and gas plant flaring have received most of the attention, there is also concern about flaring and venting from pipeline maintenance. Pipeline maintenance is often preceded by purging the line and flaring or venting the gas directly to the atmosphere. To inspect the condition of pipeline walls, a cylindrical device known as a “smart pig” is sent along the pipe; it detects and sends back data on cracking and corrosion.
|Background: Flaring in Alberta|
The Alberta Research Council study led to a review of flaring and subsequent efforts to reduce flare emissions. At the request of the oil and gas industry, a multi-stakeholder project team of Alberta’s Clean Air Strategic Alliance (CASA) was formed to develop recommendations to manage solution gas flaring in the province. The initial recommendations adopted were successful in substantially reducing emissions, but due to a lack of consensus over measures that would generate further reductions, the CASA team was disbanded in 2010.
|Flared volumes reached an all-time low in 2009 but have subsequently returned to early 2000s levels due to lower natural gas prices and increasing pipeline and compression costs.|
Despite the initial success, the regulations related to solution gas flaring were never intended to remain static over the long term. It was recognized that alterations may be necessary to account for new technologies, new production methods, and new economic conditions. The approach has not been comprehensively reviewed since 2010 when the CASA team provided their final report.
In some circumstances using an incinerator may be preferable to flaring. Some types of incinerator can burn with high efficiency and thus minimize odour and air pollution, including greenhouse gas emissions. Unlike flares, the efficiency of well-designed incinerators is not affected by cross-winds. Additionally, an incinerator reduces the noise and eliminates the light associated with flare.
A company will consider a variety of factors when determining whether to use a flare or incinerator, including cost, volume of gas flow, proximity of houses and land topography. Although the emissions from an incinerator may be less than a flare, they are released closer to the ground and may not disperse as effectively. Thus, if a well is close to a dwelling located in a hollow, a flare stack may be considered preferable to an incinerator.
After a company has drilled a well, it must be tested to determine characteristics about the oil or gas being produced, rate of production, and other factors for production. During this testing, reservoir fluids and gas can be produced and must be managed accordingly. The reservoir fluids can be stored on site before being transported for waste management. The produced gas, after it is separated from the fluids (see Drilling Wastes), can be transported in a pipeline for processing or can be flared or vented at a well site. If flaring or venting is used, air quality might be affected.
The recommendation for producers is to first try to avoid any gas emissions at all. If they cannot be avoided, the emissions should be minimized, and any emissions that do occur should meet the performance requirements. Gas capture is preferred to flaring, and flaring is preferred to venting.
The AER allows 21 days to complete well testing. Although a company can apply to the AER for a longer test period under specific circumstances, any flaring and venting during well testing must not exceed 72 non-consecutive hours. Flaring approved by the AER must conform to Alberta Ambient Air Quality Objectives and Guidelines. The challenge is that there are no requirements for ongoing air monitoring at wells that do not contain H2S, and in some instances it will not be known if these guidelines are exceeded. If you believe these operations are exceeding these standards, it is important to inform the AER immediately so that they may be able to respond to the complaint in time to measure the air quality event. Even in an instance where the individual project may still be in compliance, it can be helpful to register your complaints with the AER so they can see over time that this may be an area of concern.
|Flaring intensity during oil and gas well testing has increased consistently since 2005; in 2014 well test flaring per well drilled was over 90% greater than in 2005. This is related to the increasing number of horizontal, multistage-fractured wells being drilled.|
Well test flaring may emit pollutants that can damage vegetation and affect human and animal health. As explained in Site Selection and Setbacks, setbacks are intended to protect people from exposure, but people may wish to be alerted during well tests. The AER requires a company to notify its local field centre, the local municipality, and rural residents before testing an oil well or sour gas well using a flare that will last more than four hours in a 24-hour period. The requirements are different for oil wells and gas wells, but the minimum notification radius ranges from 0.5 km to 3 km depending on the composition of the gas being flared, duration of the flare and the gas volume discharged.
Companies are not automatically required to notify adjacent landowners or occupants when they test flare for a shorter duration. However, the AER suggests that companies conduct “good neighbour” operations, where residents have identified themselves as being sensitive to or interested in emissions from a facility.
You may want to arrange for livestock to be located upwind or away from the flare. If you or others suffer from respiratory illness, you can negotiate with the company to ensure that it notifies you when it plans to carry out its well-test flaring so you can leave the area at that time. You may want to make arrangements for the company to delay the start of a well test or to stop a test if meteorological conditions are unfavourable and would result in pollution concentrating at ground level. Although regulations require companies to ensure ground level concentrations do not exceed maximum allowable levels, general ambient monitoring is not always required.
In an established area where pipelines are already nearby, a company may be able to greatly reduce well test flaring by conducting an in-line test through a pipeline to a processing facility. However, a short period of flaring will probably be required to remove any remaining fluids from the well after it is drilled, since the fluids could cause corrosion if released into the pipeline.
If small quantities of solution gas are measured in an oil well, it may not be economic for the company to collect and pipe the gas. Instead, a company may want to install a permanent flare stack or incinerator for production from such a well. Operators with continuous solution gas flares, incinerators or vents are expected to provide public information packages with the following information:
Total solution gas flared and vented reached an all-time low in 2009, while the overall conservation rate has remained relatively stable at 95 percent through this period.
|Air emission issues at compressor stations are described in Compressor Stations. Dehydrators, which may be located at well sites, are described in Sour gas plants.|
In most years, odour is the most frequent cause of complaints to the AER. Venting of gases (especially from crude oil and bitumen batteries), tank venting, leaking tank seals or ineffective vapour recovery units on storage tanks can cause odours. If there is an odour it is important to notify the company and AER at once and ask that action be taken to locate and stop the source. If the odour is caused by H2S see What to Do in a Sour Gas Emergency for information on evacuation in emergency situations. If you are concerned that you or individuals in your household might be affected by the emissions, you may wish to leave the area. If you leave because of odours when there is no general emergency, you should notify the AER as to the reason that you left.
If you are troubled by a recurring odour, notify the AER of each event or on a regular basis. Keep a record of when events occur, noting the wind direction, wind strength, ambient temperature, and any other weather conditions that may be present during the event. You should also document your description of the odour during each event, as that may reveal details to assist finding the cause of the odour.
As indicated in Risks of sour gas, Alberta Health has reviewed the health effects associated with short-term exposure to low levels of H2S. There are still many gaps in our knowledge about the long-term effects of exposure, but “there is evidence that cumulative health effects of repeated low-level H2S exposure exist.” The specific risk of low-level exposure to H2S for the general population or sensitive people is not known.
The AER has two mobile monitoring units to measure H2S and sulphur dioxide, as well as infrared cameras that detect leaks of hydrocarbons. The AER uses these units to monitor locations where there have been odour complaints. If you have a problem, ask the AER to set up the monitoring unit in your area. Sometimes the AER will require a company to conduct its own air monitoring when they have received a complaint, or the AER may work with Alberta Environment and Parks and partner airshed organizations to conduct further monitoring, as they may have mobile monitoring equipment that can measure for more substances at lower concentrations.
It is important that any monitoring equipment is properly located in an area where the air pollution is high and where conditions lead to bad air. Thus, the equipment should be downwind, where the emissions seem to be the worst when the wind speed is low or during air inversion conditions. Landowners or occupants can suggest what they consider to be the best monitoring location based on their experiences.