6.6 TERRESTRIAL ECOLOGY
6.6.1 This Section of the assessment describes and evaluates the construction and operational impacts on terrestrial ecology in terms of the flora and fauna known or expected to occur at or near the proposed Qatalum Site (as determined in Section 5.7).
The most significant impacts are likely to arise from:
• Emissions of hydrogen fluoride and sulphur dioxide during operation of the plant;
• The physical presence of the Aluminum Plant / associated facilities and construction workers camp, resulting in permanent habitat loss;
• temporary presence of an area for the deposition, storage and dewatering of dredged materials, resulting in habitat loss; and
• General construction activities (e.g. site preparation), leading to disturbance of the land surface, resulting in potential damage to habitats, flora and fauna.
Less significant potential impacts relate to
• Operational and construction noise generation, resulting in potential disturbance to fauna; and
• Operational and construction dust generation and deposition, resulting in potential smothering of flora and fauna.
This assessment focuses on the most significant potential impacts. Where possible, mitigation and compensation measures have been considered and suggested. In light of this, the mitigation measures outlined below are proposed for consideration as measures for which financial contributions could be made in order to compensate for adverse impacts of the project.
Operational Impact Assessment – Effect of HF Emissions
6.6.2 Emissions of fluoride from the proposed facility may cause damage to plants in terms of tissue damage, or death, if exposure occurs above a certain level. Terrestrial plants may accumulate inorganic fluorides following airborne deposition and uptake from the soil50, 63. Exposure to a high concentration of fluoride causes necrosis (tissue death) of part, or even the whole, of the leaf. In most monocotyledonous (narrow-leaved species including grasses and lilies) plants, the initial symptom is the development of chlorosis (yellowing) at the tips and margins of elongating leaves (see Figure 6.16). In dicotyledonous (broad-leaved) species the initial symptom of fluoride effects on leaves is usually chlorosis of the tip, which later extends downward along the margins and inward toward the midrib. Continued exposure may lead to the tip becoming necrotic and falling off, leaving the leaf notched. The availability to plants tends to decrease with time following initial application of fluoride. The degree of accumulation depends on several factors, including soil type and, most prominently, pH. At acidic pH (below pH 5.5), fluoride becomes more phyto-available through complexion with soluble aluminum fluoride species (which are themselves taken up by plants, or, increase the potential for the fluoride ion to be taken up by the plant). The soils of Qatar are generally alkaline, due to the limestone geology of the area, thus limiting the availability of fluorides to plants in this area.
Figure 6.16 – Leaf Necrosis in the Lily
6.6.3 In general, plant species are particularly vulnerable to injury during the growing season when leaves are young, and during daylight hours when gas uptake rates are high. However, some plants, typically hardy and salt tolerant coastal species, grow on the made/disturbed ground and three “natural” plant communities were identified:
? The vegetation of coastal sands; consisting mostly of halophyte species;
? Reed bed vegetation, associated with the discharge of treated effluent from the adjacent MIC sewage treatment plant; almost entirely dominated by Phragmites australis; and
? Vegetation fringing the reed bed proper; consisting of grasses and chenopods.
A summary of the indigenous and ornamental/landscaping species identified, and their sensitivities to fluoride, is provided in Appendix E. The areas of vegetation in closest proximity to the Qatalum Site are illustrated in Figure 6.17.
Figure 6.17 – Areas of Vegetation in Proximity to the Qatalum Site
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6.6.4 To assess the potential for damage to occur, the modelled ground level concentrations of hydrogen fluoride have been compared with air quality standards and guidelines. There are currently no regulatory standards for HF emissions in Qatar and none have been identified in other Middle East countries. The MIC Authority has proposed a draft guideline9 of 1 µg/m3, as a monthly average, albeit suggested for the protection of human health xix, rather than vegetation. The WHO recognizes that levels in ambient air should be less than 1 µg/m3, to prevent effects on livestock and plants63. This guideline applies to long-term exposure (assumed to be equivalent to a one year averaging period) xx. For other averaging periods, an illustrative sample of air quality standards from other countries, for the protection of vegetation, are presented in Table 6.6.
Qatalum have questioned the scientific basis of this draft guideline as a measure to protect human health; this has been discussed previously in Section 6.3.
Qatalum will submit a more comprehensive study on applicable international ambient HF criteria as a standalone document.
Table 6.6 – Vegetation Air Quality Guidelines for Gaseous Fluorides (µg/m3)
Country Averaging period
24 hours 7 days 30 days Annual
WHO – – – 1.0
Norway (non-statutory guideline) 1.0 – 0.4
Japan 1.0 0.5 – –
Texas, USA 2.9 1.7 1.0 –
Queensland, Australia 2.9 – 0.84
6.6.5 The standards / guidelines in Table 6.6 have been designed to protect specific / the most sensitive receptors, usually plant species, and are devised so that the highest concentrations are acceptable for only the shortest durations. It should also be noted that the plants and soil types in the Mesaieed area are likely to be quite different to those in the countries listed in Table 6.6; therefore, any assessment against these standards should be regarded with caution. There is a greater degree of uncertainty relating to guidelines / standards for short averaging periods (e.g. 7 day, 24 hour, 1 hour), particularly when they have been derived with country specific sensitive species in mind, thus, this assessment only considers the monthly and annual standards presented in Table 6.6 for comparison with the modelling results. The Figures presented in this Section showing the presents the maximum monthly mean concentrations of hydrogen fluoride; the contour lines show that the concentrations are above the non-statutory Norwegian guideline of 0.4 µg/m3 across the majority of the Industrial Area. Based on the non-statutory Norwegian guideline there may be some visible damage to reeds, which are more sensitive than the coastal vegetation, at concentrations above 0.4 µg/m3. The landscaping plants which are used in the Industrial Area alongside roads and offices are, on the whole, tolerant species and are therefore unlikely to be affected by the concentrations of between 0.4 and 2 µg/m3 which were modelled within the greater part of the Industrial Area. The trees planted along the road parallel to the south western site boundary may show some signs of necrosis with concentrations of up to 10 µg/m3 over a small localized area (less than 500 m). Although these trees are generally hardy, as implied by their existence in an industrial zone and their tolerance of an arid, salty environment; based on the modelled concentrations and the standards in Table 6.6, some impact (e.g. partial defoliation) cannot be ruled out.
Figure 6.18 – Maximum Monthly Average HF Concentrations, µg/m3
Figure 6.19 – Maximum Annual Average HF Concentrations, µg/m3
6.6.6 Figure 6.19 presents the annual mean concentrations of hydrogen fluoride. The contour lines show that the concentrations are below the WHO guideline of 1 µg/m3 across the majority of the modelled area. Therefore, based on the modelled annual concentrations, no damage is likely, even to the most sensitive plant species. There is a much localized area close to the pot rooms, within less than 600 m of the Main Site south western boundary, where modelled concentrations are between 2 and 7 µg/m3. The trees planted in this area, along a small section of the road parallel to the south western site boundary, may be susceptible to damage. The assessment indicates that the extent of the potential impact of fluoride emissions will be limited to the immediate local area, in particular, to roadside plantings directly adjacent to the site’s south western boundary within the MIC Industrial Area. On the basis of the above, and in the absence of mitigation / control measure, the impact of HF emissions on flora is anticipated to be minor; however, as a further precaution and in light of various uncertainties, the impact has been assigned as moderate.
Operational Impact Assessment – Effect of SO2 Emissions
6.6.7 Sulphur dioxide penetrates into leaves primarily in gaseous form through the stomata. Under dark or drought conditions, stomata are closed and resistance to gas uptake is very high giving the plant a very low degree of susceptibility to injury. The WHO has set a value of 10 to 30 µg/m3 (depending on vegetation type) as an annual mean critical level for sulphur dioxide, based on effects on terrestrial vegetation. The soils of the Middle East were assigned to “Class 5” (see Figure 6.20), which is defined by UNEP/RIVM64 as being insensitive to acid deposition. Therefore the effects on plants of acid deposition to soil are not considered further within this impact assessment.
Figure 6.20 – The Global Distribution of Soil Sensitivity to Acid Deposition
6.6.8 A contour plot of modelled annual mean concentrations of sulphur dioxide is presented in the Air Quality Assessment Section, in Figure 6.9. This figure illustrates the rapid decrease in concentrations with increasing distance from the source. The contour lines show that concentrations are below the WHO vegetation guideline of 20 µg/m3 across the majority of the modelled area, including most of the MIC Industrial Area. There is a limited area close to the south western Qatalum Site boundary where modelled concentrations approach the WHO vegetation guideline of 20 µg/m3. SO2 emissions will be continuous throughout the operational life of the Qatalum Project. On the basis of the above, the impact of SO2 emissions on flora is anticipated to be negligible to minor. The main source of SO2 emissions from the process has been reduced by 90% through the selection of a seawater scrubbing gas treatment system. As for the potential effects of HF, visual monitoring of vegetation will be undertaken to determine whether any damage is caused, no further mitigation techniques are considered necessary.
Operational Impact Assessment – Minor Impacts (Noise and Dust)
6.6.9 Noise has the potential to disturb fauna, particularly during breeding seasons. The noise assessment (see Section 6.7 below). In addition, Dust deposition, resulting for example from material handling activities, has the potential to smother flora. Dust generation during operation of the plant has been minimized through, emissions control and will be further controlled through the environmental management system. Due to other construction activities and the widespread and heavily disturbed desert surface in this region of Qatar; thus this impact is considered to be of negligible significance.
Operational Impact Assessment – Non-Typical Operation
6.6.10 Activities related to process upset conditions have not been specifically addressed but are not considered likely to result in any impacts that are of a significantly greater magnitude than those experienced during typical plant operation.
Construction Impact Assessment – Impacts on Habitats, Fauna and Flora
6.6.11 The construction of the plant will result in the permanent loss of terrestrial habitat as a result of the presence of the Aluminum Plant and associated facilities. reed beds; man-made inland water bodies such as these have been identified as being of potential local importance for wildlife such as invertebrates and birds .The impact on the habitat and vegetation in the remaining Project Areas is considered to be of negligible significance, on the basis that this consists of mostly of sparse vegetation, with low species diversity, and which is similar to many other areas within Mesaieed and Qatar.
Reed bed Habitat Loss Mitigation and Residual Impact
6.6.12 Assuming that an appropriate and equivalent method of compensation can be agreed, and implemented successfully, it is anticipated that the residual impact on the reed bed (habitat loss) would be reduced to minor, or even negligible. The loss of habitat through land-take can also impact on non-avian terrestrial fauna. No mammals were observed during the Ecological Survey or site walkovers, but MIC supports at least three native mammal species, most of which are likely to be widespread and locally common in Qatar. Since the quality of habitat affected is considered to be generally poor, the impact is considered to be of negligible to minor significance.