MANILA, Philippines — Mark Allan Arevalo, Wawao Builders general manager, invoked his right against self-incrimination when asked whether his firm was involved in ghost flood control projects. Arevalo was among the contractors who attended the Senate Blue Ribbon Committee investigation on questionable flood control projects. "I invoke my right against self- incrimination," Arevalo said when Senate President Pro Tempore Jinggoy Estrada asked whether they had flood projects in Bulacan. "Hindi po ako sigurado (I'm not sure)," Arevalo said when Estrada asked him if his firm has flood control projects in Bulacan. Estrada said that Wawao has 42 projects with the Department of Public Works and Highways. "The bulk of your projects is in Bulacan, [you have] two in San Juan [City], in Quezon City, Ilocos Norte, Kalookan [City], and Laguna. And they have identical [project] cost: P77 million," he told Arevalo.