1 Fish Farm Wastes in the Ecosystem
17
legal commitments to meet individual directive requirements that, in general, are
transposed into UK law by means of regulations or other forms of secondary legislation
issued as statutory instruments. A regulation identifies the competent regulatory authority
and the actions required of it in order to achieve the directive’s requirements. … It is primarily
regulations and directions passed by the UK or Scottish Parliament, which impose obligations
on SEPA, as the competent authority, to deliver the objectives and standards so transposed
from an EC Directive.
The “Control of Pollution” Act (COPA) of 1974 marked the beginning of marine
pollution control in the UK, although it took a decade to implement fully. The main
regulatory tool is the “consent to discharge” from a “point source” such as a waste
pipe or a fish farm. According to its web site (SEPA 2005a),
SEPA has a duty to control discharges to surface waters and groundwaters [in
Scotland], including tidal waters out to the three-mile limit. SEPA does this by issuing
a legally-binding consent to discharge under the Control of Pollution Act 1974.….
Where consent is granted this will include specific conditions to limit the effects that
the discharge may have upon the receiving environment. Monitoring will be carried out
by the discharger and SEPA to ensure that the impacts of the discharge remain within
acceptable levels.
Thus, anyone wishing to establish or extend a salmon farm in these waters must,
amongst other legal requirements, make an application for a consent to discharge
the waste from the farm. Then (SEPA 2005b),
SEPA will impose consent limitations on the maximum permitted fish biomass which
may be held at any time. This is designed to minimise accumulation of organic wastes
on the sea bed to prevent anoxic and polluted sediments and associated deleterious
effects on the normal benthic fauna outwith the allowable zone of effects. In certain
instances to protect important wild salmonid stocks, SEPA will limit the biomass to
that which can be treated at the site using an authorised sea lice medicine [without
exceeding environmental quality standards for these medicines]. … SEPA will [also]
limit consented biomass to ensure that the receiving water will not be [at risk of
eutrophication].
An allowable zone of effects, or AZE is a small region beneath fish cages where
some impact is allowed. SEPA accepts
that a certain area immediately below and around the cages may experience carbon accretion to a level which may change the community structure of sediment fauna. Within this
AZE quality standards ensure a minimum number of sediment re-workers will be available
to breakdown wastes and prevent total anoxia developing.
Two salmon farming sites have been consented in loch Creran, each of 1,500 t
maximum biomass; however, only one site is available at a time, because each site
is required to lie fallow for two years between use, in order to allow recovery of the
benthos in the AZE.
The “Wildlife & Conservation” Act of 1981 has been used to implement the
European “Habitats” Directives of 1992/1997 and the “Birds” Directive of 1979. It
protects wild birds, and certain other animals, and plants that have been officially
listed, together with designated sites. UK regional conservation agencies, exemplified by Scottish National Heritage (SNH), work under this law. The agency’s web
site (SNH 2006b) explains that
17
legal commitments to meet individual directive requirements that, in general, are
transposed into UK law by means of regulations or other forms of secondary legislation
issued as statutory instruments. A regulation identifies the competent regulatory authority
and the actions required of it in order to achieve the directive’s requirements. … It is primarily
regulations and directions passed by the UK or Scottish Parliament, which impose obligations
on SEPA, as the competent authority, to deliver the objectives and standards so transposed
from an EC Directive.
The “Control of Pollution” Act (COPA) of 1974 marked the beginning of marine
pollution control in the UK, although it took a decade to implement fully. The main
regulatory tool is the “consent to discharge” from a “point source” such as a waste
pipe or a fish farm. According to its web site (SEPA 2005a),
SEPA has a duty to control discharges to surface waters and groundwaters [in
Scotland], including tidal waters out to the three-mile limit. SEPA does this by issuing
a legally-binding consent to discharge under the Control of Pollution Act 1974.….
Where consent is granted this will include specific conditions to limit the effects that
the discharge may have upon the receiving environment. Monitoring will be carried out
by the discharger and SEPA to ensure that the impacts of the discharge remain within
acceptable levels.
Thus, anyone wishing to establish or extend a salmon farm in these waters must,
amongst other legal requirements, make an application for a consent to discharge
the waste from the farm. Then (SEPA 2005b),
SEPA will impose consent limitations on the maximum permitted fish biomass which
may be held at any time. This is designed to minimise accumulation of organic wastes
on the sea bed to prevent anoxic and polluted sediments and associated deleterious
effects on the normal benthic fauna outwith the allowable zone of effects. In certain
instances to protect important wild salmonid stocks, SEPA will limit the biomass to
that which can be treated at the site using an authorised sea lice medicine [without
exceeding environmental quality standards for these medicines]. … SEPA will [also]
limit consented biomass to ensure that the receiving water will not be [at risk of
eutrophication].
An allowable zone of effects, or AZE is a small region beneath fish cages where
some impact is allowed. SEPA accepts
that a certain area immediately below and around the cages may experience carbon accretion to a level which may change the community structure of sediment fauna. Within this
AZE quality standards ensure a minimum number of sediment re-workers will be available
to breakdown wastes and prevent total anoxia developing.
Two salmon farming sites have been consented in loch Creran, each of 1,500 t
maximum biomass; however, only one site is available at a time, because each site
is required to lie fallow for two years between use, in order to allow recovery of the
benthos in the AZE.
The “Wildlife & Conservation” Act of 1981 has been used to implement the
European “Habitats” Directives of 1992/1997 and the “Birds” Directive of 1979. It
protects wild birds, and certain other animals, and plants that have been officially
listed, together with designated sites. UK regional conservation agencies, exemplified by Scottish National Heritage (SNH), work under this law. The agency’s web
site (SNH 2006b) explains that