applied sciences Article A Hybrid Approach Using Fuzzy AHP-TOPSIS Assessing Environmental Conflicts in the Titan Mining Industry along Central Coast Vietnam Manh Tien Dao 1 , An Thinh Nguyen 2, *, The Kien Nguyen 2 , Ha T.T. Pham 3 , Dinh Tien Nguyen 2 , Quoc Toan Tran 2 , Huong Giang Dao 1 , Duyen T. Nguyen 1 , Huong T. Dang 1 and Luc Hens 4 1 Institute of Resource, Environment and Sustainable Development, Hanoi 10000, Vietnam 2 University of Economics and Business, Vietnam National University (VNU), Hanoi 10000, Vietnam 3 University of Sciences, Vietnam National University (VNU), Hanoi 10000, Vietnam 4 Vlaamse Instelling voor Technologisch Onderzoek (VITO), Boeretang 200, 2400 Mol, Belgium * Correspondence: nathinh@vnu.edu.vn; Tel.: +84-912-300-314 Received: 1 July 2019; Accepted: 18 July 2019; Published: 22 July 2019   Abstract: Environmental conflict management gains significance in rational use of natural resources, ecosystem preservation and environmental planning for mineral mines. In Central Coast Vietnam, titan mines are subject to conflicting use and management decisions. The paper deals with an empirical research on applying a combination of the fuzzy Analytic Hierarchy Process (AHP) and the fuzzy Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) to measure environmental conflicts emerging as a result of titan mining in Vietnam. The methodology used in the paper combines the fuzzy AHP and the fuzzy TOPSIS to rank environmental conflicts and propose conflict prevention solutions in the titan mining industry of Ky Khang coastal commune (Ky Anh district, Central Coast Vietnam). Data was collected by using a questionnaire with 15 locals, 8 communal authorities, 2 district authorities, and 12 scientific experts on titan mining, environmental geology, and sustainability management. The result shows that, titan mining conflicts with the eight criteria of economic sectors at five alternative sites including beach, protected forest, agricultural area, settlement area, and industrial area. The conflicts between titan mining and forestry, agriculture, settlements, fishing and aquaculture are highly valued. The beach area shows most environmental conflict as a result of titan mining, followed by the agricultural area and settlement area. Based on the empirical findings, legal and procedural tools such as environmental impact assessments, strategic environmental assessments, integrated coastal zone management, marine spatial planning, and multi-planning integration advancing environmental management for titan mines in Vietnam are suggested. Keywords: fuzzy AHP; fuzzy TOPSIS; titan mining; environmental conflict; Ky Anh; Vung Ang Economic Zone; Central Coast Vietnam 1. Introduction Environmental conflicts, which originate as a result of environmental pollutions, resource use competition, and social conflicts, emerge when stakeholders take part in activities with contradictory interests, values, power, perceptions, and goals. Environmental conflicts cover different issues: Biodiversity conflicts [1–3], coastal zone conflicts [4–7], air pollution conflicts [8], land use conflicts [9,10], and water conflicts [11–14]. Most recently, environmental conflict is considered in relation to economic, development and social issues in the context of global climate change [15,16]. Worldwide, environmental conflicts challenge the economic security at both local, regional, national, and global scales [17,18]. Appl. Sci. 2019, 9, 2930; doi:10.3390/app9142930 www.mdpi.com/journal/applsci