Abstract. Characterization and seasonal (periodic) monitoring of plant species distribution in the context of former industrial activity is crucial to assess long-term anthropogenic footprint on vegetated area. Species discrimination has shown promising results using both HyperSpectral (HS) and MultiSpectral (MS) images. Airborne HS instruments enable high spatial and spectral resolution imagery while time series of satellite MS images provide high temporal resolution and phenological information. This paper aims to compare supervised classification results obtained with non-parametric (Random Forest, RF, Support Vector Machine, SVM) and parametric methods (Regularized Logistic Regression, RLR) applied on both kinds of images acquired on an industrial brownfield. The studied site is a complex vegetated environment due to species diversity: 8 dominant species are retained. The performance obtained by preliminary feature selection based on principal component analysis and vegetation indices, to improve separability of spectral or temporal information according to species, is analysed. The best performance is obtained by RLR method applied on HS data without feature selection (global accuracy of 93 %). Feature selection is found to be a necessary step to perform classification with time series of MS images. Species that are difficult to distinguish from the HS image, namely Salix and Populus, are well separated using Sentinel-2 images (precision around 70%).

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Total E&P Uganda undertook a 3D seismic survey in Exploration Area 1/1A lying within the Murchison Falls National Park. During the survey, an impact mitigation program was applied to; Avoid unnecessary damages; Minimize unavoidable damages; Restore damages; and Offset any residual damage to ecosystems. Here, we describe highly innovative approaches used in Avoidance, Minimization, and Restoration of impacts presented as a model for future operations in similar sensitive ecosystems. A simplified Avoidance model was designed to implement avoidance while Minimization involved use of alternative technologies such as cable-less technology, and vegetation mapping. Restoration involved use of both manual and mechanical methods. Unmanned Aerial Vehicle was also used to scout predefined seismic lines and monitor restoration. Ecological Compliance Officers supervised activities on ground to ensure enforcement of the Avoidance Mapping Procedure, identification of impacts and overseeing restoration of impacted areas. Consequently, there were generally few impacts resulting from avoidable damages. Impacted areas were identified, mapped and later restored. In total 64 tracks, 59 upholes and 30 patches were fully restored. Total of 40,328 avoidance features were mapped along approximately 3500kms of seismic lines. 678 features were later sampled and revisited after operations to assess compliance to Avoidance. Only one feature, a burrow was found impacted upon, having a tyre mark depression implying it may have been trampled by a vehicle.Observations indicate compliance by the Seismic crews, further suggesting the mitigation hierarchy is an effective impact mitigation measure. The seismic survey was very intensive and the first of its kind in such a sensitive ecosystem employing highly innovative technologies such as use of cable-less data acquisition implemented for the first time in Africa. Application of the UAV was highly innovative, as well as the creative Simplified Avoidance Model which provides an extensive knowledge, technicalities and experience in avoiding impacts in such operations.

TOTAL have recognised the fact, that there has been a need to put more focus on the environmental aspects associated with major accidents hazards. Major accidents as defined by the Offshore Installations (Offshore Safety Case) Regulations 2015 have been specifically assessed by the UK affiliate to identify if they could result in a Major Environmental Incident(s) (MEIs); in line with the EU Directive 2004/35/EC on environmental liability with regard to the prevention and remedying of environmental damage. Hydrocarbon releases of over 1,000bbls have therefore been modeled using the OSCAR software for events such as topside / subsea releases and wells blow outs in order to define fate and location of hydrocarbons from these releases. The exposure/effect (acute mortality, population loss, quantity of oil reaching/endangering shoreline habitats) of the releases on Valued Ecosystem Components (VECs) has then been assessed to define restitution time of the relevant organisms/habitats. Results of the modeling have been assessed so that any event that has a potential effect on the VECs classed by the Company as "Catastrophic" (>3years restoration time) or above is classed as MEI. The incidents not identified as MEIs are then screened along with other liquid releases using a complementary method. This method utilises a matrix to define the environmental severity, based on the volume and toxicity of the release as well as the sensitivity of the marine environment and when relevant (shoreline) the extent of the release. The above Offshore Safety Case regulation defines Safety and Environmental Critical Elements (SECEs) as "parts of an installation where either (a) failure could cause or contribute substantially to a major accident or (b) it has a purpose to prevent, or limit the effect of, a major accident". For major accidents potentially resulting in MEIs, a review of existing barriers was undertaken to demonstrate their adequacy and sufficiency. As an outcome of this process, Critical Elements performance standards were reviewed and amendments proposed as required.

Total Exploration and Production Uganda undertook a 3D seismic survey in Exploration Area 1/1A lying within the Murchison Falls National Park inhabited by many species of wildlife. During the seismic survey, an ecological avoidance program was applied to; i). Scout and map all sensitive features within the seismic footprint, ii). Avoid impacts on sensitive features and maintain their ecological integrity, iii). Proactively demonstrate sustainable oil & gas extraction in a sensitive ecosystem. A mitigation hierarchy of; Avoidance, Minimization, Restoration and Offsetting residual impacts was followed to limit ecological impacts. In this paper, we focus on Avoidance, presented as a model for future seismic or other intensive operations in similar sensitive ecosystems. This involved systematic surveys of predefined seismic lines for sensitive features, mapping locations of features, sensitizing Seismic crews, and on-ground supervision of Avoidance implementation. A total of 25,484 features such as; lekking grounds of ungulates, clay-licks and wallows were mapped along approximately 3300km in total of seismic lines surveyed. Out of 25,484 features mapped, 10,169 significant features were sorted, from which 678 features were sampled and revisited after seismic operations to assess compliance to Avoidance. Out of 678 features revisited, only one, a burrow was found to be impacted upon, having a tyre mark depression implying it was trampled by a vehicle. Three other burrows were found filled with soil, but with no indication of whether this was due to anthropogenic or natural occurrence. Five hundred and twenty features were found to have signs of animal activities such as; footmarks and physical presence of animals, including birds, indicating continued use of the features after seismic operations. The results indicate compliance by Seismic crews, suggesting that the Avoidance Mapping Procedure is an effective impact mitigation measure especially in such sensitive ecosystems. No such intensive seismic operation had been undertaken before in such a sensitive ecosystem. Some impact minimization measures used such as cable-less seismic data acquisition were implemented for the first time in Africa during these surveys. The Avoidance Mapping Procedure designed and applied was as well therefore the first of its kind, and provides an extensive knowledge, technicalities and experience in avoiding and minimizing impacts during seismic operations in such sensitive ecosystems.