A remote coastal training centre normally pumps fresh groundwater from a borehole. When the borehole pump is being maintained, seawater may provide the entire water supply.
Two treatment arrangements have been proposed.
| Arrangement | Treatment route |
|---|---|
| 1 | Water from whichever source is available enters one storage tank. Water leaving the tank goes through sand and gravel filter beds and is then exposed to ultraviolet light. |
| 2 | Groundwater goes through sand and gravel filter beds. Seawater instead goes through a high-pressure membrane. Water from either route enters a storage tank and is treated with ozone as it leaves the tank. |
Compare the suitability and energy requirements of the two treatment arrangements for producing potable water.
87 exam-style questions on AQA GCSE Chemistry 10.1 Using the Earth's resources and obtaining potable water, covering 10.1.1 Using the Earth's resources and sustainable development, 10.1.2 Potable water, 10.1.3 Waste water treatment, and 10.1.4 Alternative methods of extracting metals. Each one has a worked solution and a mark scheme showing where the marks go.