National Pollutant Release Inventory (NPRI)
2008 Facility Data Summary
3. Summary of reported on-site releases, disposals and transfers for recycling
3.1 On-site releases
On-site releases reported to the NPRI for 2008 totalled over 4.2 million tonnes. Air pollutant emissions, including criteria air contaminants, or CACs (the key pollutants that contribute to poor air quality, smog and acid rain), accounted for 97.0% of reported on-site releases. Releases to water made up 2.9% of total on-site releases. On-site releases to land (spills and leaks) made up 0.2% (Figure 3.1-1).
Releases to water accounted for 52.6% of reported on-site releases (excluding air emissions of CACs), followed by releases to air of other substances of concern (44.2%) and releases to land (3.3%). (See Figure 3.1-2.)
On-site releases are discussed in more detail in the sections that follow.
The types of releases to air that must be reported to the NPRI are direct discharges through a stack, vent or other release point. Losses from storage and handling of materials, fugitive emissions, spills and accidental releases, and other non-point releases are also reported to the NPRI. In this summary, releases to air are reported under two groups: criteria air contaminants (CACs) and all other (non-CAC) substances.
Criteria air contaminants (CACs) are a group of air pollutants that affect human health and contribute to air pollution problems such as smog, acid rain and poor air quality. They include total particulate matter (TPM), particulate matter less than or equal to 10 microns (PM10), particulate matter less than or equal to 2.5 microns (PM2.5), sulphur oxides (SOx), oxides of nitrogen (NOx), volatile organic compounds (VOCs) and carbon monoxide (CO). Because CACs make up a large proportion of reported releases to air, it is beneficial to examine them separately from other releases to air.
For 2008, 4.0 million tonnes of CAC emissions were reported to the NPRI. Figure 22.214.171.124-1 shows a breakdown of these reported releases by industry sector (it is important to note that individual CACs differ in terms of their health and/or environmental impacts, and cannot be directly compared).
Facilities reporting to the NPRI are not the only sources of CAC emissions in Canada. Other sources of CAC emissions include facilities that are not required to report to the NPRI as well as non-facility emission sources such as forest fires, motor vehicles and residential fuel wood combustion. CAC emissions from both industrial and non-industrial sources are compiled and made available annually by Environment Canada.
Table 126.96.36.199-1 compares the releases of CACs reported to the NPRI with the latest estimates for emissions from all human activities (i.e. excluding natural sources), as compiled by Environment Canada. Facilities reporting to the NPRI account for a large proportion of national CAC emissions for some substances, but a small proportion for others. For example, facilities reporting to the NPRI account for almost all of the sulphur dioxide emissions in Canada, but for a relatively small share of total particulate matter (TPM) emissions, which are primarily released from vehicle travel on paved and unpaved roads, construction operations, and agriculture.
|Substance||2008 releases reported to the NPRI (tonnes)||National CAC emissions (2007) excluding natural sources (tonnes)|
1 562 186
1 903 423
9 152 911
|Oxides of nitrogen (expressed as NO2)|
2 268 812
|Volatile organic compounds (VOCs)|
2 271 341
|PM - total particulate matter|
18 502 880
|PM10 - particulate matter ≤ 10 microns|
5 951 756
|PM2.5 - particulate matter ≤ 2.5 microns|
1 133 417
For 2008, releases to air of non-CAC substances totalling 102 709 tonnes were reported to the NPRI. Figure 188.8.131.52-1 shows reported non-CAC releases broken down by substance. The largest reported releases were of ammonia, methanol, hydrochloric acid and sulphuric acid. These substances accounted for approximately half of the non-CAC releases to air reported to the NPRI for 2008.
As noted above, individual substances vary in terms of their effects on the environment and human health. In addition, substances with the greatest quantities of reported releases are not necessarily those of greatest health or environmental concern. Some substances can be a concern even when released in small amounts.
Reported releases to water include direct discharges to surface water as well as spills and leaks. While this category includes discharges to water from municipal wastewater treatment plants and other facilities, it does not include discharges to municipal wastewater treatment plants. These are reported under off-site transfers for treatment prior to disposal.
As shown in Figure 3.1.2-1, most of the 122 201 tonnes of releases to water reported to the NPRI for 2008 were from facilities in the Water, Sewage and Other Systems sector. This sector includes municipal sewage treatment facilities that receive and treat much of the large amount of wastewater produced by households, businesses and industries.
Wastewater contains a number of pollutants such as nitrate ion, ammonia and phosphorus. In 2008, these were the substances released to water in the largest reported quantities (Figure 3.1.2-2). Wastewater can also contain small amounts of certain metals such as zinc, copper, mercury and cadmium.
Releases to land reported to the NPRI include spills, leaks and other uncontrolled releases of pollutants. These releases do not include disposal methods such as landfilling, underground injection or land treatment, which are reported to the NPRI as "disposals." In 2008, most of the releases to land were Ethylene glycol, used primarily as a de-icing agent by facilities in the Support Activities for Air Transportation and the Defence Services sectors. The Defence Services sector also reported sizable releases to land of copper, lead and zinc, resulting mainly from the firing of weapons at training facilities.
As defined by the NPRI, disposal methods include on-site disposals (at the facility location), off-site disposals (at another facility) and off-site treatment prior to final disposal. On-site disposal includes landfill, underground injection and land treatment. Off-site disposal includes these same categories, plus storage. Off-site transfers for treatment prior to final disposal include physical, chemical, biological, incineration/thermal, and sewage treatment. For more detailed descriptions of these categories refer to the NPRI Guide for Reporting 2008 (PDF format 1.44 Mb).
On-site disposal refers to the disposal of substances within the boundaries of the facility. The difference between an on-site disposal and an on-site release is that a disposal is a more controlled method of discarding waste, whereas a release is a direct discharge to the environment. An on-site disposal can be reported as underground injection, landfill or land treatment. Land treatment means the distribution of material upon or insertion into the land surface for the purpose of pollutant removal, assimilation or utilization. Disposal of material in a confined area, such as in a landfill, is not land treatment.
Figure 3.2.1-1 shows that the disposal of hydrogen sulphide by underground injection made up the majority of the total reported on-site disposals for 2008. Hydrogen sulphide is a naturally occurring but highly toxic substance in raw natural gas and must be removed before the gas can be safely transported to market. All of the hydrogen sulphide that was reported to the NPRI as an on-site disposal was disposed of by underground injection. Underground injection is a regulated waste disposal method in which materials are injected into deep underground wells.
Off-site disposals are similar to on-site disposals, with the exception that the reported substances are transferred off site to another facility for final disposal. A breakdown of off-site disposals reported to the NPRI for 2008 is shown in Figure 3.2.2-1. As with on-site disposal, off-site disposals reported to the NPRI are dominated by underground injection of hydrogen sulphide reported by the oil and gas extraction industry.
Off-site transfers for treatment occur when a facility sends a substance to another facility for further treatment prior to final disposal in order to reduce the substance's impact on the environment. A breakdown of reported transfers for treatment prior to final disposal for 2008 is shown in figures 3.2.3-1 and 3.2.3-2.
Over three quarters of reported off-site transfers for treatment prior to final disposal were for treatment at municipal sewage treatment, chemical treatment, and incineration and thermal treatment plants. Sulphuric acid, ethylene glycol and ammonia account for the greatest percentage of substances transferred off site for treatment.
Facilities that meet the reporting criteria are required to report on the transfer of substances tracked by the NPRI to off-site locations for recycling and energy recovery. "Recycling" refers to activities that keep a material or a component of a material from becoming a waste destined for final disposal. The NPRI identifies nine types of recycling activities:
- recovery of solvents;
- recovery of organic substances (other than solvents);
- recovery of metals and metal compounds;
- recovery of inorganic materials (other than metals);
- recovery of acids and bases;
- recovery of catalysts;
- recovery of pollution abatement residues;
- refining or reuse of used oil; and
- other recovery, reuse or recycling activities.
Off-site transfers for energy recovery are reported by facilities when the substance or the material containing it has sufficient energy content to allow its use as an alternative to fossil fuel or other forms of energy.
Over one million tonnes of NPRI substances were sent off site for recycling and energy recovery in 2008. As shown in Figure 3.3-1, recycling of metals and metal compounds accounted for 14.0% of total reported transfers for recycling and energy recovery. The Non-Ferrous (except Aluminum) Production and Processing and Motor Vehicle Parts Manufacturing sectors accounted for most of the transfers of metals and metal compounds for recycling reported in 2008. The substance sent for recycling in the largest quantity in 2008 was hydrogen sulphide, mostly from oil and gas processing facilities. Many oil and gas facilities send hydrogen sulphide to be processed into elemental sulphur for use by other industries.
Under Canadian Environmental Protection Act, 1999, the Minister of the Environment can require a company or facility to prepare and implement a pollution prevention plan. Pollution prevention planning is the process of examining current operations and developing a plan to eliminate or reduce pollution at the source. A pollution prevention plan involves the use of processes, practices, materials, products, substances, or energy that prevents or minimizes the production of pollutants and waste and reduces the overall risk to the environment and human health. Specific or targeted pollution prevention plans can focus on a particular substance of concern, whereas a broader pollution prevention plan can target an entire production process or even an entire facility.
For the 2008 reporting year, 3570 facilities reported to the NPRI that they undertook some form of pollution prevention. The four most frequently reported types of pollution prevention activities were good operating practices and training, spill and leak prevention, equipment and process modifications, and on-site recovery, reuse or recycling.
Use the NPRI Online Data Search website to search pollutant release and transfer data for facilities in your community.
- Due to rounding, some of the figures presented in this Summary may not add up to 100%.
- In order to avoid double counting, Total Reduced Sulphur (TRS) is not included in the analysis above. For a summary of TRS reported to the NPRI for 2008, see Part 1A of the 2008 NPRI Summary by Substance. For more information on potential double counting and other NPRI data analysis issues, please see the Considerations When Using NPRI Data page.
- NPRI data as of September 28, 2009, were used for the analysis above. Updates reported by facilities since that date are not reflected in the Summary. For this reason, totals generated using the NPRI Online Data Search tool may differ from those presented here.
- Date Modified: