Source of emissions
Like any industry, the offshore oil and gas industry inevitably generates several waste streams during exploration and production activities. These waste streams are of two types:
- operational wastes that are discharged to sea under permit or authorisation, for example produced water
- other wastes, which are unwanted materials that are stored on the installation and returned to shore for disposal or recycling
These materials range from inert platform wastes (e.g. general waste, paper, glass, cardboards etc) and garbage to scrap metals, empty metal and plastic drums, oils, sludge and chemicals. It is these latter wastes that are considered here.
Click here for more about environmentally aware waste removal and recycling services.
The volume of waste varies with the level of maintenance, drilling and production activities. Scrap metals are generated during shutdown, construction and/or refurbishment. Plastic and metal drums are employed for the supply and use of chemicals offshore. Special wastes arise from drilling for natural gas, workover and platform maintenance activities and mostly include residual hazardous fluids e.g. biocides, surfactants, emulsifiers, corrosion inhibitors, oxygen scavenger, greases, fuels, hydraulic oils, paints, thinners, lubricants, anti-freeze, cleaning solvents and batteries.
The future of gas production must be more environmentally responsible. Click here to read more.
Potential environmental impacts
Although some wastes are inherently hazardous, they will only present a risk to the environment if they are improperly managed. Modern disposal and recycling techniques such as engineered landfill, incineration and recovery of waste oils minimise the environmental impact.
Disposal to landfill is costly and not sustainable in the long term and operators seek to segregate wastes to reduce the quantity of material going to landfill and to maximize reuse or recycling. There are some waste streams that are currently difficult to dispose of other than by landfill.
All offshore operations are subject to individual operator environmental management systems which will recognise waste disposal as having the potential for environmental effect. Operators will therefore seek to continually improve the management of wastes through the adoption of a waste management plan.
Installations Regulations dealing with the discharge of hydrocarbons and chemicals from offshore installations as operational wastes also prevent the use of the marine environment as a disposal route.
Although regulation of these wastes does not begin until the wastes are onshore, personnel on the installation will ensure that the different wastes are appropriately segregated to facilitate appropriate treatment onshore.
The controls on waste originate from the Control of Pollution Act 1974 and were greatly tightened with the introduction of the Environmental Protection Act 1990. Legislation originally focused on the disposal of waste, but since the introduction of the EC Framework Directive on waste (Directive 75/442/EEC, amended as Directive 2006/12/EC and Directive 2008/98/EC) control has extended to include the storage, treatment, recycling and transport of waste.
Anyone who imports, produces, carries, keeps, treats or disposes of waste is subject to a duty of care whereby they must take all reasonable and applicable measures:
- To ensure that waste is stored and transported appropriately and securely so it does not escape
- To check that waste transferred to people or businesses that are authorised to do so
- To complete waste transfer notes (WTNs) to document transfers.
The Duty of Care is designed to be an essentially self-regulating system, based on good business practice. Its purpose is to prevent the practice of waste producers simply handing their waste over to anyone prepared to take it away, without giving consideration to where it is going and whether it will be dealt with properly. It also ensures there is a clear audit trail from when the waste is produced until it is disposed of.
Find out more about environmental practices – visit this site