It is well known that mixing slurry can produce toxic gasses like hydrogen sulphide (H2S), which is invisible although it smells like rotten eggs. In a confined area, like a slatted floor shed, it can rapidly suffocate animals or humans.
Adding silage effluent to slurry increases the risk as it feeds the bacteria which produce the H2S gas. Gypsum or calcium sulphate, which is increasingly being used for animal bedding, contains raised levels of sulphur, encouraging the production of even more H2S when it is incorporated into slurry.
Following a number of recent livestock deaths in Scotland and Northern Ireland, the statement provides formal guidance on restrictions associated with the material.
The guidance highlights how the use of recycled gypsum as animal bedding would require a waste management licence as there is no exemption, within Scottish environmental legislation, for this material to be used in such circumstances.
However, due to the associated risk to animal and human health, it would be unlikely Sepa would be able to grant a licence if it were to be used as animal bedding.
As there are no exemptions in the waste legislation to allow the use of waste gypsum and waste plasterboard as animal bedding, any such uses may be reported to the procurator-fiscal as an offence under Section 33 of the Environmental Protection Act 1990.
Stephen Field, land unit manager of Sepa, said: "The disposal of plasterboard, gypsum and gypsum-containing wastes can lead to the production of the highly odorous, and toxic gas, H2S. Due to its high levels of sulphate, gypsum, and wastes with similar properties, cannot be land-filled with biodegradable waste in Scotland.
"When used in animal bedding, it is likely waste gypsum will produce considerable levels of H2S due to the damp, non-ventilated conditions. In such circumstances, H2S presents a significant risk to animal and human life, as well as the environment, and we would advise against anyone using it for this purpose until there is clear, scientific evidence to demonstrate it does not pose such a risk".
l Rural communities in Scotland can now apply for support to help buy their land, Environment Minister Stewart Stevenson announced yesterday.
The new £6 million Scottish Land Fund – which will be delivered by Big Lottery Fund Scotland and Highlands and Islands Enterprise – will empower communities by helping them acquire land and opens for applications on Monday, July 2.
UNITED Auctions sold 177 store bullocks at Stirling yesterday to a top of 251.6p per kg and an average of 206.3p (-2.3p on the week), while 84 store heifers peaked at 222.7p and levelled at 201.2p (-1.5p). In the rough ring, 75 cast cows averaged 145.3p.