The 2014 OSPAR Guidelines for management of dredged material at sea set the standards for sampling and assessing the Severn Estuary dumping site, and it specifies points to be included in a license. NRW has a duty to follow these guidelines, but show no evidence of doing so, writing their own criteria, taken from previous dumping practice.
OSPAR's sampling guidance
5.2 …
The distribution and depth of sampling should reflect the size and depth of the
area to be dredged, the amount to be dredged and the expected variability in
the horizontal and vertical distribution of contaminants. Core samples should
be taken where the depth of dredging and expected vertical distribution of
contaminants suggest that this is warranted.
5.3 The
following table gives an indication of the number of separate sampling stations
required to obtain representative results, assuming a reasonably uniform
sediment distribution in the area to be dredged:
Amount dredged (m3)
|
Number of Stations
|
Up to 25 000
|
3
|
25 000 - 100 000
|
4 – 6
|
100 000 - 500 000
|
7 – 15
|
500 000 - 2 000 000
|
16 – 30
|
5.4 The
original individual samples should, however, be retained until the permitting
procedure has been completed, in case further analyses are necessary.
The Hinkley excavations will produce some 300,000m3 down to 4 metres depth. The only borehole samples of the deeper sediments were in 2009 and showed the radionuclides are signficantly worse deeper down. OSPAR's para. 5.2 requires sampling of the "vertical distribution of contaminants".
NRW required only surface sampling (to a few cm, by grab sampler) which obtains recent deposits of the mobile mud swishing around Bridgwater Bay. The deeper mud from decades-old deposits when nuclear discharges were poorly controlled is assessed only by the 2009 samples. OSPAR says the 5 core samples in 2009 were insufficient; more than 7 – 15 were needed, to obtain scientifically representative results. NRW were wrong to claim "no scientific justification" for further sampling at depth as the Petitions Committee asked.
At the Senedd
debate in Plenary session on 23 May, the Welsh Minister just repeated NRW's false claim
.No scientific basis for further testing... A robust and thorough process – can assure everyone CEFAS
working to highest standards...have made
their assessment fully in line within international standards...Clear evidence has been given - no radiological risk to people or the
environment.
If the second part of this is also untrue - as our 23 August blog-post shows - OSPAR's rules say
6.2 If
dredged material is so poorly characterised that proper assessment cannot be
made of its potential impacts on human health and the environment, it shall not be deposited at sea.
OSPAR's rules also cover Biological characterisation
6.9 Biological
tests should incorporate species that are considered appropriately sensitive..
6.10
Assessment of habitats communities and populations may be conducted in parallel
with chemical and physical characterisation, e.g. triad approach. It is
important to ascertain whether adequate scientific information exists on the
characteristics and composition of the material to be deposited and on the
potential impacts on marine environment and human health.
6.13 An Action List should include upper and
lower levels giving these possible actions:
a. material which contains specified
contaminants or which causes e.g. biological responses, in excess of the
relevant upper levels should generally be considered unsuitable for normal sea
deposit but suitable for other management options, see paragraphs 7.4 – 7.6
below;
b.
material of intermediate quality, below the upper level but exceeding
the lower level, should require more detailed assessment before suitability for
deposit at sea can be determined ; and
c. material which contains contaminants
below the relevant lower levels should generally be considered of little
environmental concern for deposit at sea.
In this case, testing for chemical contaminants found several toxic metals and organics exceed the lower level, making the material "intermediate quality" as in 6.13b. NRW didn't bother with the detailed assessment covering sensitive species (6.9) that's required for any sea dumping, and doubly needed for dumping in the Severn Estuary European SAC site "Special Area of Conservation". They simply completed a pro-forma HRA which repeats "there is no impact pathway from the proposal to the designated feature" for each species of fish and birds; this apparently based on the years of previous dumping of dredgings, with no regard to the particular toxic components in the Hinkley dredgings, largely of deep material.
OSPAR rules also cover assessing the dumping area:
8.2 For the evaluation of a sea deposit site
information should be obtained and assessed on the following, as appropriate:
a. the
physical, chemical and biological characteristics of the seabed (e.g.,
topography, sediment dynamics and transport, redox status,
benthic organisms);
b. the
physical, chemical and biological characteristics of the water column
(e.g., hydrodynamics, dissolved oxygen, pelagic species);
c. proximity to:
(i) areas of natural beauty or significant
cultural or historical importance;.
(ii) areas of specific scientific or biological importance (e.g.
Marine Protected Areas);
(iii) recreational areas;
(iv) subsistence, commercial and sport fishing
areas;
(v) spawning, recruitment and nursery areas;
(vi) migration routes of marine organisms;
(vii) shipping lanes;
(viii) military exercise zones;
(ix) past munitions dump sites;
(x)
engineering
uses of the sea such as undersea cables, pipelines, wind farms
(xi)
areas
of mineral resources (e.g. sand and gravel extraction areas); and
d. the
capacity of the site should be assessed, taking into account:
(i) the degree to which the site is
dispersive;
(ii) the allowable reduction in water depth
over the site because of mounding of material.
(iii) the
anticipated loading rates per day, week, month, or year
NRW have no study, nor did they require EdF to produce one. This would normally have been supplied via an EIA (Environmental Impact Assessment); NRW wrongly claimed that EdF had made an EIA to cover the dumping, though CEFAS told them not.
OSPAR rules also cover permit conditions, ignored by NRW:
10.3 Permit conditions should be drafted in plain and unambiguous language
and will be designed to ensure that:
a. only those materials which have been
characterised or considered exempted from detailed characterisation according
to paragraph 6.3, and found acceptable for sea deposit, based on the impact
assessment, are deposited;
b. solid
waste
contained within the dredged material should be separated and managed on land;
c. the material is deposited at the selected deposit
site;
d. any necessary deposit management
techniques identified during the impact analysis are carried out; and
e. any monitoring requirements are
fulfilled and the results reported to the permitting or supervising authority.
10.4 A
permit to deposit dredged material that is assessed to be contaminated according to national
assessment criteria shall
be refused if the permitting authority determines that appropriate
opportunities exist to reuse, recycle or treat the material without
undue risks to human health or the environment or disproportionate costs.
,Since CEFAS had assessed the mud as "contaminated" above Action Level-1, under this 10.4, NRW had to consider alternatives to sea-dumping, that could include landfill for restoration. The company application says they considered using the material on the construction site, but dismissed using the silt as too fine (it could obviously be used for landscaping). They dismissed dumping on-shore, as it would be washed away (!), but failed to consider it for soil improvement, land restoration or landfill (more costly). NRW did set a requirement to 'minimise dispersion' during dumping, but failed to specify depositing via pipe to the bottom and/or restricting dumping to times of low current (on turn of the tide) in accord with OSPAR:
11.7 Operational
controls can include temporal
restrictions on deposit activities, such as tidal and/or seasonal restrictions
