Managing Emissions to the Water Environment Flashcards
What are the general classifications of water pollutants?
> physical - eg litter, suspended solids, heat and radioactivity
> chemical - eg acids, alkali, pesticides, etc
> biological - eg harmful pathogens, in water that cause disease, eg viruses and intestinal parasites
What is Oxygen Stress?
effluents that contain a high level of organic matter (human sewage - strip oxygen from receiving waters.
Substances,( such as iron) will combine with oxygen in water, thus reducing the amount of freely available oxygen for wildlife.
What are the main effects of Solids in water?
main effects are aesthetic as you can see, smothering plants and animals on the bed of the watercourse, damaging fisheries, and interfering with self-purification.
How can Acids and Alkalis effect water bodies?
changes in pH leads to change in the biodiversity of the water course and the release of secondary pollutants such as metals.
What can Phosphorus and Nitrogen Compounds do to water bodies ?
Can indirectly remove oxygen from the water by the process of eutrophication.
What can Hydrocarbons do to water bodies ?
Oil may coat the leaves of aquatic plants and other organisms such as birds, in addition to impacting on oxygen exchange.
What can Pesticides do to water bodies ?
Acute release of pesticides into water has been found to kill aquatic life and may cause thyroid disruption.
Persistent Organic Pollutants?
These are a group of substances that can accumulate in fatty tissues of any organism and, as they degrade very slowly, can bioaccumulate in food chains posing a high risk to human health and the environment (eg a number are carcinogenic)
What is the effect of Thermal increase in water?
raised temperature can have the effect of reducing the amount of oxygen in the water and altering bio-diversity.
Pathogens and Parasites?
sewage and animal waste contain pathogenic micro-organisms (viruses, bacteria, protozoa, and intestinal paretic eggs) which may cause disease.
Chlorine and Chlorine Containing Compounds?
Tricholorethylene (TCL) is a common industrial solvent. Ingestion of which in drinking water may lead to liver damage and increase the risk of various types of cancer.
Heavy Metals?
Such as mercury and cadmium have the ability to bioaccumulate in food chains. The effects of this bioaccumulation will vary depending upon the substance, eg mercury may cause nervous system impairment, dizziness, coma and death.
Explain Point and Diffuse Sources of Pollution.
> Point Sources of water pollution are those where there is a distinct controlled discharge into the watercourse
> Diffuse sources are those that do not enter a watercourse through controlled sources
Detail the practical Methods of Pollution Prevention.
> Identifying, Marking and Maintaining Drains
Binding
Pipework
Deliveries
Drum and IBC Storage
Spill Kits
Spillage Control Management
Identifying, Marking and Maintaining Drains
A drainage plan of the site is necessary for effective pollution control.
Education of the different uses of the different drains is also important.
Recommended that surface water drains are marked as blue and foul water drains as red.
Practical Means of Pollution Prevention - Binding.
> should be constructed of sturdy material, or lined with sturdy material, impervious to the material to be contained.
> they should comprise a base and surrounding walls (with no damp course
> The capacity of the bund should be the whole capacity plus 10% as a minimum.
> ice there is more than one tank in the bund it should be at least 120% of the combined capacity
> even if tank is double skinned should still follow the same requirement as traditionally bounded tanks
Practical Means of Pollution Prevention - Pipework
> Should be above ground where possible
> Filler pipes should be within the bund and vent, overflow pipes should be positioned to overflow into the bund
Practical Means of Pollution Prevention - Deliveries
Deliveries should be isolated from surface water drains in the event of a spillage
> automatic cut-off valves should be fitted to oil delivery points to prevent over-filling.
Practical Means of Pollution Prevention - Drum and IBC Storage
> bunding of an oil-containing drum are a drip tray of a capacity of 25% of the volume of the drum
> for IBC containing oil, the requirements are 110% of the largest container or 25% of the total of the containers (whichever is the greater)
Practical Means of Pollution Prevention - Spill Kits
provision of a spill kit is sound practice
they should be appropriate to the substances used on site and training must be given.
Spill kits should be accessible - so their location is important
Practical Means of Pollution Prevention - Spillage Control Management
A pollution incident control plan should be prepared based on the spillage control hierarchy:
- contain at source
- contain close to the source
contain on the surface
- contain in the drainage system
- contain on or in the watercourse
All spillages must be cleaned up and disposed of in line with legal requirements for waste
What are the elements of Mitigating the Effect of Fire Water Run Off?
control methods to be implemented include:
- containment lagoons and sacrificial area
- penstock valves
- consulting enforcement authorities
- fire-fighting strategies
What is the Purpose of Effluent and Water Monitoring?
- legislation often dictates requirements to sample and monitor effluent discharges (permits and consents to discharge will identify Emission Limit Values (ELV)
- monitoring of water use by a site is normally undertaken as part of a water minimisation scheme (to assist in the reduction of costs and environmental impacts associated with water use)
- standard tests using accredited laboratories is essential if results are to be relied upon and for legal purposes
Explain the Role of the Environmental Practitioner in Water Pollution Monitoring
-specific competencies are required for monitoring standards which are dictated by law
- MCERTS standards state competency requirements for those undertaking the chemical testing of sewage and trade effluents
- those undertaking sampling should be deemed to be competent to do, falling in line with any competence standards that may be set in permits/consents and/or assocaiated guidance
