Geological Context and Statistical Assessment of the Impacts of Sugarloaf Twin Disasters, in Western Sierra Leone

In the event of natural disasters, Sierra Leone like any other country loses lives as well as properties and natural resources. Despite notable occurrences of small disasters in the country, only on August 14 th sugarloaf landslide and the resulting flash flood (twin disasters) which affected Regent and other communities in 2017 have captured both national and international attention due to their alarming impacts. To obtain a better knowledge on the nature of the disasters, this research considered the geological context of the landslide and focused on statistical analysis of the impacts of the twin disasters using Statistical Package for Social Sciences (SPSS). Geological field-based approach and self-administered questionnaires of both closed and open-ended ques-tions, personal interviews and observations were adopted as research tech-niques. Descriptive statistics and qualitative analysis were used to analyze the data of the research. Relevant literature from books, journals, and newspapers was also consulted, including Radio, Television discussions and the internet. Slope destabilization that caused the Landslide was linked to the geology of sub-surface formation (highly weathered olivine gabbro), lineaments and the rate of weathering. Study showed remarkable economic, social and political impacts as a consequence of the twin disasters. Study also revealed that families assisted the most in both financial and non-financial ways to the victims, and renowned misappropriation of donated disaster funds. All variables tested using student t-distribution and chi-square test of independence accepted the hypothesis. Information obtained from this work could be fundamental for policy makers and development practitioners


Introduction
Landslides are ascertained as serious natural hazard common to mountainous or steep land areas across the continents; including Europe, Asia, South/North America and Africa. Its downward and outward movements are principally driven by gravity, which affects only a limited portion of the hill slope, with clearly defined boundaries at top, bottom, sides and the base (BGS, 2018). Their occurrence takes different formats, including slope failures, mudflows, and mass movements, which end up modifying the landscape and consequently cause severe damages and losses. Due to the huge fatalities and enormous damages attributed to landslide, particularly in topographically hilly zones globally, it is ranked as the third most dangerous disaster (Feizizadeh & Blaschke, 2011). This establishes the relevance for identifying the natural (geological) conditions controlling and triggering landslides and also statistically showing its associated impacts, which inform rational decision in line with landslide risk management.
Landslides represent a serious geologic hazard (USGS, 2015) that results in loss of lives and property damages (Ramakrishnan et al., 2002). Globally, the figures for both damages and losses have risen considerably in the last decade, amounting to 32,322 recorded fatalities (Nsengiyumva et al., 2018). According to the United Nations' analysis, of the 346 recorded disaster incidents in 2015, a total of 22,773 people lost their lives. Analysis also shows that people affected from the same disasters reached a total of 98.6 million with an economic loss of USD 66.5 billion. It is surprising to note that landslide alone in the midst of other disasters affected 150,332 people with a death record of 4369 worldwide (p. 2). The world's poorest and wettest regions i.e. villages and cities across west and central Africa, face a worsening threat from the disaster according to researchers. Igwe (2017) reported that similar landslide incidences have claimed the lives of 4000 people over the past 10 years, and the loss of multi-million dollar resources each year in Africa (McAllister, 2017). These have posed serious constraints on the economic development of these developing countries, where the economic loss due to its impacts often distinguishes between economic growth and stagnation (Westen, 2000).
Freetown, the capital city of a small West Africa country, Sierra Leone, has been struck by different types of mass movements/landslides and associated flash flood (see historic and recent slides in Figure 1 Journal of Geoscience and Environment Protection tember, has made it susceptible to landslides and flooding. City planning has been given little priority in the EU-funded Freetown Development Plan created in 2014. As a result, homes/houses have been constructed in areas identified as "at risk". Also, protected forest areas on the hills behind the city including other prohibited areas have all been encroached contributing to most slope failures (Egbejule, 2017). Despite the fact that the Freetown Layered Complex has significant natural ground instability due to landsliding, little or no related scientific research has been done, offering the peninsula as an excellent site for landslide causative factors and impact studies.
The research will therefore bridge gaps and improve landslide knowledge for future initiatives related to landslide risk reduction and management in this part of the country. Furthermore, the outcome of the impact study will bring potential economic, social, political and by extension environmental effects to the knowledge of policy makers and development practitioners.  Encyclopedia, 2017). But the victims were the hardest hit of the disasters than the non-victims. The effect of the twin disasters on both victims and non-victims cannot be over emphasized.
Mitchell (2017)  The results of field investigations were crucial to identify geological conditions controlling and triggering the landslide. The flash flood resulted from an intense rain that fell on Sierra Leone from 1 st July-14 th August 2017. The World Bank (2017) estimated 1040 mm of rain during this period, exceeding three times more than the average. Affected communities considered in the research, including Matormeh, Kaningo, Pentagon, Lumley, Kroobay and culvert, show negative economic effects. Ameliorating this requires huge cost of expenditure in rebuilding new communities for the victims and the provision of medical facilities for the injured (Amnesty International, 2017). Also, entertainment and political process were disrupted as a result of the disasters.

Study Area Profile
Sugarloaf landslide occurs at Matormeh, which is located in the outskirt of Freetown that overlooks regent mainland and the Congo Reservoir, and is also strategically located southward in a protected area of the National park. It falls within zone-3 of the topographic map of Freetown layered complex and also found on sheet-2 of the western area of Sierra Leone (Chalokwu, 2001). The The area is characterized by undulating mountain ranges with tight narrow valleys dissecting the surrounding hills. The landslide's epicentre is steep, and has a slope gradient of >60˚ (Sillah & Williams, 2017). Geomorphologically, the landslide area is seemed denuded due to anthropogenic activities (forest logging and settlement).

Field Work
This includes the extensive non-consecutive fieldwork carried out for Thirteen The next three days (7 th -9 th September, 2017) concentrated on self-delivered questionnaires. The study population accounted for only the local residents of the affected communities. They include headmen/elders, teachers, students, traders, skilled workers and NEC registration officers. A stratified simple random sampling selection of victims at each community was adopted, with a sample size of sixty (60) victims of the twin disasters. The last seven (7 th -13 th October, 2018) days of the former trip was dedicated to monitoring of discontinuities (fracture width in this case), nearby potential sliding zones and other informal interviews.
The latter trip done together with UNOPS and BGS involved site visit for ground truthing, observation of landslide deposits on slopes and along stream channels, taking of drone images/photographs and informal interviews with locals on the impacts of the disasters.

Statistical Method
The second part of the research was based on the impacts of the twin disasters in the study area, Freetown. For this reason, both qualitative and quantitative methods were used as described by Salkind, 2006. The qualitative research methodology was used because the research involved the meticulous description of the impacts of the twin disasters on Freetown municipality. The quantitative research methodology on the other hand was equally used because the exercise involved a great deal of number work, as the raw data collected for the study were cautiously analyzed and presented in statistical form; using Statistical For test of hypothesis, various variables were tested using Student's t-Distribution Test and Chi-square Test at 5% significance difference. This was done by inputting codes/data values into the Software Packages for Social Science (SPSS) system ranging from 1 -8 and others 1 -3 respectively. This method is simple and it is widely used in journal publications.
The research tools employed were questionnaires, conversational interviews, and personal observations. More precisely, sixty (60) questionnaires were administered. To complement the questionnaire method, conversational interviews and personal observations were also utilized by the researchers.

Geological Context
The Sugarloaf landslide consists of variable slope gradients along the flanks. The Western flank is steeper than 60 degree towards the head scarp and a range between 20 and 30 degrees at the bench, where as the slope of the eastern flank is Y. A. Lahai, P. S. Lahai Jr.
greater than 45 degree at the top and between 20 -25 degrees towards bench.
Despite the study area's geomorphology is indicative of natural ground instability, understanding the geological framework of the rainfall-triggered landslide is pivotal to link slope destabilization due to sliding to the underlying rocks and structural geological conditions.

Geology
Fractured and layered gabbroic rocks (olivine gabbro, gabbro and basaltic dykes) underlie the landslide area (See Figure 3(b)). The much visible major fracture set at the headscarp has a WNW-ESE trending. Two minor fracture sets consti-

Weathering
Weathering of the fractured/jointed and bedded intrusive underlying gabbroic rocks is intense. More cracks were generated by water and possible lineaments,

Types of Materials and Movement
The landslide generated different types of materials, proportionately distributed over the entire landslide area and along stream courses, including boulders (1.5 -5  Figure 6 illustrates the proportional distribution of landslide materials, mud tracks and material movements.

Effects of Landslide and Flash Flooding
This part provides both qualitative and quantitative data derived from tech-     (Gibbins, 2017). The two sectors, mining and agriculture, on which the country depends on to generate its Gross National Income (GNI), were badly affected.

Economic Effect
For the agricultural sector, the forest that is made to produce timber, wild life conservation, the quality of water was affected. This portrays that, in terms of monetary value, the timber and wildlife were all lost instead of increasing the GDP of Sierra Leone. Some mining companies operating on certain minerals were halted because of the recent report that stated that the sector was one of the major causes of mudslides, which in turn will reduce the GNI. From the sample, ($1) a day (Dumbuya, 2018). Furthermore, not only has agricultural sector affected, but also the commercial sector (Small Scale Business Centres) such as petty trading, hairdressing, weaving, catering services, carpentry, dressmaking, barbing shops, shoemaking (Kamara, 2017a). These activities done in affected communities were disrupted/destroyed which was another setback for livelihood sustainability of families as indicated in the chart. These Small Scale Businesses (SSB) play a pivotal role in the social, socio-cultural and economic development of the country. They contribute positively to the living standard of people.
2) Humanitarian Assistance deadly disasters that struck on that day, those donations and funds were diverted (Kamara, 2017b). In the wake of natural disasters, people always seize the opportunity to survive, as there are now some people claiming to be victims/survivors of this disaster to make ends meet. This is because there has been vast majority of individuals suffering to get a daily meal to survive. Freetown This labour force could have lived to contribute to the GDP for national development. It is indeed a big blow/setback to Sierra Leoneans and not only the victims/survivors of the deceased (Baraytay, 2017). The twin disasters record the worst ever in the history of Sierra Leone which has gone through many trials from the civil war to the 2014 EBOLA outbreak. The disasters occurred so fast within six hours (6 hrs.) and caused massive deaths of Sierra Leoneans. However, family members in Freetown and less disaster affected areas are presently providing great deal of support to people affected by these disasters as portrayed on the chart. Though some are receiving financial assistance as well as items like mattresses, kitchen utensils, food, clothing, shelter; etc. the bulk of this financial assistance came from siblings, children and family friends. But some are still claiming of not getting any financial assistance since the disasters struck.

Social Effects 1) Education and Health
From the chart described by Figure 9 (left), 16.7% (f = 10) victims indicated that "School Buildings" were destroyed in the twin disasters; 11.6% (f = 7) victims indicated "Hospital" was destroyed; 15% (f = 9) victims indicated "Pharmacy" was destroyed; 6.7% (f = 4) victims indicated "Clinic" was affected; and 50% (f = 30) victims indicated "School building, Pharmacy, and Clinic" were destroyed when the disaster struck in the affected communities. On this note seventy-five percent of sixty victims agreed that children affected have stopped attending school as many school buildings were destroyed when the disasters struck. But this has reversed the process with the advent of new government flagship programme 2018 "Free Education for Primary and Secondary School".
As indicated from the chart; education, pharmacy and clinic have the highest percentage of destruction from the disasters. Education is the backbone of a country's development, so it is a priority for individuals' personal development (UNDP, 2015). In this light, the schooling of hundreds of children was affected as those victims' parents died or if alive, their properties were destroyed. As Mbalu Bangura (2017) lamented "I have no chance to go back to school because our properties have all been destroyed and my parents are not working". This young girl lives in the Kaningo community, she is 15 years old and she worries about her continuing school. The most vulnerable children are the female children whose parents were wounded/dead in the event of these natural disasters.
Some are left without much help from siblings to take care of them, and without option they have dropped out of school. These girls are forcefully raped which result in teenage pregnancy, or some volunteer to give themselves to commercial sex. On the other hand, Jeneba Kanu, a 16 year old and SSS2 pupil also lamented that her parents were all dead in the twin disasters, and she was staying with her uncle, a charcoal seller with 8 children who cannot alone take all the responsibilities and her contemplation was to involve in commercial sex. The boy-child, on the other hand is now exploited as domestic workers engaged in petty trading, hawking pure water or other domestic work in order to earn money for the exploiters. School buildings have been affected during these disasters as some are buried in the debris of the mudslide or washed away by the flooding. These schools were the main pillars for sustaining community developments. These schools contributed to educational development which in turn increases the GDP via tax collection by the National Revenue Authority (NRA) Sierra Leone (Sierra Leone MoFED, 2017). Taking a look at their health sector, these communities were benefiting from hospitals, clinics, pharmacies etc. But that day, they were all gone due to the strike from the disasters. In other words, pharmacy and clinic were there to provide medical facilities for the people in the affected community but now majority are sick without proper medical care especially children and lactating mothers. Unless they have to travel farther to unaffected communities for medication. This greatly involves huge transportation cost.
These medical centres also generate income for the owners who in turn pay tax to the Government of Sierra Leone that spurs up the GDP that could be used for national development.

2) Religion
The chart represented by Figure 10  facility, building schools for members and non-members of the community.
Shelters, food, and clothing were also provided by mosques and churches in those communities. However, most of these mosques and churches were destroyed in the wake of those disasters in that part of Freetown. This massive destruction has caused the affected communities to be without churches and mosques which were contributing positively to national development. This basically portrays the reduction in the country's GDP as they were paying royalties.
For entertainment process, it was discovered that eighty-three percent of sixty (60) victims stated that entertainment process has been seriously affected in those affected communities. Some of these entertainment activities are cultural dance, football, film-show, and other sports respectively. Community development always hinges on entertainment centres for football, and other sports.
These activities bring social cohesion and also create employment within the community for sustainable development. Entertainment centres like community centre, cinema halls, cultural dance, present in these communities were affected by the dreaded disasters which destroyed them all. Football and other sporting activities are the major entertainment activities that bring people together. Not only were they bringing people together, but were contributing to the income generations for the community development. This income was used to build schools, repair bad roads, provision of pipe borne water by the strong will of councillors (Kamara, 2017b). However, the disasters stopped all the activities that were generating income for the affected communities (Mansaray, 2017).
Thus, this was not good for the overall development of Sierra Leone, and will require time and money to rebuild these communities or finding new settlements. It is the responsibility of the Government of Sierra Leone, to judiciously use the Gross National Income (GNI) or donation (funds) to rebuild the affected communities, since this country is a donor driven country.  Figure 11 (left) reveals, 41.7 (f = 25) victims indicated "Strongly Agree" that election process would be affected in those affected communities considering the number of death of people. While 33.3 (f = 20) victims indicated "Agree" that election process are deem to be affected; 16.7 (f = 10) victims indicated "Don't Know" whether or not election process would be affected as a result of the disasters. Also, 3.3 (f = 2) victims indicated "Strongly Disagree"; and 5 (f = 3) victims indicated "Disagree" that the election process would be affected as a consequence of the disasters on the 14 August, 2017 in the early morning hours.

Political Effects
As the chart portrays that forty-one point seven percent did strongly agree that political process can also be affected when disaster strikes in any country.
According to National Electoral Commission (NEC, 2017) the forthcoming election is one sure way that has been presently affected considering the number of

Test of Variables and Hypothesis
The undermentioned variables were statistically tested via the use of Student's t-Distribution Test and Chi-square Test of certain parameters such as t cal , t tab , v(df),  from Table 3 and thus we reject H O and accept H A to justify the alternative hypothesis stated above. In this vein it is true that whenever natural disaster occur in any country, in which Sierra Leone is no exception; this will negatively affect the economic, social and political process.

Conclusion
This work has presented results of geological investigations and the impacts of the disasters on economic, social, and political processes in Sierra Leone using SPSS. Therefore, the following conclusions could be drawn.
The research revealed that geological conditions played dominant role in the rainfall-triggered sugarloaf landslide underlain by fractured/jointed/bedded gabbroic rocks. Lineaments at the upper part of the slope (fault/fractures/joint sets) greatly influenced the landslide occurrence under the influence of gravity and constitute the sliding form. Relatively thick residual soil comprising numerous boulders, and cobbles indicating differential weathering, underwent rapid mass movement down slope with the presence of water (triggering factor) to form the debris slide, which eventually graded into boulder bounce. Slope destabilization at the lower gradient is strongly related to weathering, making the basal region susceptible to stream erosion and other surface processes.
For any negative effects generated from natural disasters, especially landslides and associated flash floods, there are also positive ones; including contribution to aquatic and terrestrial biodiversity, the supply of sediments/substances and woody debris to maintain pool habitat in streams and huge amount of funds

Recommendations
In addition to the geological context of the landslide, which dominance in the rainfall-triggered hazard on August 14 th is clear, further work on geotechnical investigation and analysis would be vital to predict the landslide occurrence and the threshold level of triggering process. This can aid in defining the threshold level of early warning and support informed policies and the development of appropriate technology for landslide hazard mitigation. Therefore, trained and qualified geologists, engineers should work in tandem with the Environment Protection Agency (EPA) and Office of the National Security (ONS) in Landslide Disaster Management (LDM) which reduces landslide risk in endangered regions and mitigate the extent of the disaster. Education and awareness raising should be prioritized for all and sundry regarding the deadly effect of landslides and associated flash floods. In this scenario; schools, libraries of all genres should be stock with books on disaster management and protection and encourage the public to inculcate the habit of utilising libraries. There should also be community sensitization on proper housing planning and good road construction with better drainage system that could last for long.
Government of Sierra Leone-social welfare and religious group should provide psycho-social counselling for the post traumatic disorder disaster victims.