Daily Pollution

Pollution occurs at all stages of oil and gas production. Liquid, solid, noise, gaseous and aerosol discharges and emissions are released during seismic testing, exploratory drilling, extraction and transportation phases. As a result, more than 800 pollutants could enter into the ocean. The contribution of oil pollution alone is tremendously significant – over 30 percent of the total oil input into the North Sea is from the offshore oil industry.

In the Water
While spills and blowouts are major concerns, drilling muds and produced waters are dumped into the ocean every day. A single production platform can drill 70 to 100 wells and discharge over 90,000 metric tons of drilling fluids and metal cuttings into the ocean in its lifetime. The cumulative impacts of drilling a single well have the potential to affect a spatial area of 1000 metres. To give you some idea, over 400 wells have been drilled on the east coast of Canada. Almost 60 wells had to be drilled before Hibernia was discovered. And today, Hibernia drills 120 wells from its platform.

Drilling muds are released into the ocean on a daily basis. Drilling muds are essential elements for modern drilling. They are designed to lubricate and cool the working drill bit and drill pipe, remove cuttings from the bottom of the well, control and regulate pressure, stabilize and seal the sides of the well and prevent accidental blowouts. The volume of drilling muds ranges from 1000 to 5000 cubic metres for each well. The toxins released from drilling muds vary with the composition of the drilling mud and their impact on marine life depends on such variables as depth, current, substrate type and wave regimes.

Water-based muds and synthetic drilling muds are used on Canada’s east coast. These are thought to be less toxic than oil-based drilling muds, however there are concerns about their impacts on the marine ecosystem. For example, synthetic-based muds are water insoluble and do not disperse in water – they tend to sink to the bottom. The distribution and fate of these materials has not been extensively studied.

Water-based drilling muds are less toxic then oil-based muds, but barium and bentonite are associated with water-based muds and have been detected as far as 8000 metres from a well. In one case, barium was detected 65 kilometres west and 35 kilometres east of an exploratory drilling site after drilling stopped. Increases in other trace metals have been associated with water-based muds. These include arsenic, cadmium, chromium copper, mercury lead and zinc, however, compared to barium, their distribution was much more spatially limited.

Produced waters are one of the main sources of oil pollutions in the areas of offshore oil and gas production. According to the Russian scientist Dr. Patin, produced waters are responsible for 20 percent of all oil discharges from the oil and gas activity in the North Sea region. In Cook Inlet, Alaska, industry dumps at least 2 billion gallons of produced water into the Inlet each year. With oil content at 30 to 40 parts per million, it roughly equates to 70,000 gallons of pure oil dumped into Cook Inlet each year.

Preliminary research by scientists in Norway shows that produced water from offshore oil exploration could be seriously harming cod in the North Sea.

In experimental conditions, chemicals dissolved in waste water from oil platforms stunted the growth of the fish and affected their breeding patterns. Scientists at the Norwegian Marine Research Institute in Bergen found that when cod were exposed to this solution, their eggs became smaller and spawning was delayed. It remains to be seen what this means for wild populations, but this initial research shows there are reasons for concern and further study.

In the Air
The effects on human and animal health from flaring are significant. Flaring occurs when gas is burned off to test a well’s potential, to deal with a well malfunction, or to separate gas from oil deposits. Research shows emissions from flaring contain more than 250 toxic compounds, including sulphur dioxide, a lung and heart irritant, benzene, a known carcinogen, nitrogen oxide, a known asthma trigger, and toluene, a toxin linked to reproductive problems. These pollutants can travel 300 kilometres downwind, where they can affect the health of people and animals far away from the drilling site. A single offshore rig emits the same quantity of pollution as 7000 cars driving 80 kilometres a day.