Review of Chemical Recoveries Sewer Releases

We have for the last 6 years provided a range of statistics on our operations as part of our open policy and these have now all been updated for 2006.

As a major treatment plant of waste water we treat all our own surface waters and those from wastes we bring in through these plants.

All waters off-site are thus released to Sewer.

Chart 1 shows the volumes of COD IN as shown in maroon which reflect the wastes we bring in for processing. The efficiency for 2005 was lower than in 2004 and the new digester plants should improve this in 2006

Chart 1

We measure a number of other parameters.

Chart 2 shows the suspended solids increased considerably in 2002 and 2003 as a by-product of our Biological Treatment Plant which will produce organic solids which we clarify and centrifuge (producing around 1000 tonnes of cake per annum). The improvements documented in previous years for suspended solids continued in 2005.

Chart 2

Chart 3 shows the volume of metals we release which remains largely static they are however dependent on the load of incoming metals which are not recorded here

Chart 3

9 Feb 2007