During a courtesy visit with President
Rodrigo Duterte in
Davao City, Lopez initiated an environmental lecture for Duterte about the need for a better national environmental policy. Duterte then asked her to be his secretary for environment. A few days later, she accepted the offer and was formally appointed by the president to head the Department of Environment and Natural Resources or DENR. She was grilled by social media on her appointment because of her family name,
Lopez, which is much regarded as a Filipino business tycoon surname. She hit the ground running on the very first day in office. She audited all mining sites and firms in the entire country and stripped environmental certificates from a chunk of the
mining industry due to massive violations against the environment and the law, the first time a secretary of environment had done so. This led to a massive public show of support for Lopez's work as DENR secretary and an apology to her for the grilling she suffered on social media. Few of the many notable certificates that were stripped were those for mining companies doing operations in
Semirara Island (a key biodiversity area) in
Antique,
Eastern Samar,
Surigao del Sur which is home to indigenous Lumad communities, and
Cordillera Administrative Region, which is the melting pot of the northern Luzon indigenous people. Lopez advocated a
100% renewable energy Philippines and was vehemently opposed to mining having stated,
"The Philippines does not need mining." Her anti-mining sentiment was backed by years of Philippine research on mining, both ecologically and economically. She also said that there would be no mining operations of any form on Palawan, which is popularly known as the last ecological frontier of the country. Within less than 2 months, she audited all mining firms from
Luzon,
Visayas, and
Mindanao. She was also an indigenous people (IP) advocate. She immediately established forums for consultations between the DENR and the indigenous people sector in the Philippines, the first time a DENR secretary did so. She also established the first ever DENR public hotline wherein the public could report all environmental violations of any entity in the country directly to the DENR and her office. She was against nuclear energy due to years of research on the matter. The Nuclear Power Plant in
Bataan will only contribute to less than 0.5% to the National Energy Grid when operated and its costs will be much higher, making it unsustainable. She preferred the establishment of more wind and solar power plants, which are massively cheaper and sustainable in the long-run, and the possible cooperation of the Philippines and
Australia to establish the first wave energy plants in
Asia. The Philippines is the center of the
Pacific Typhoon Belt, bestowing it with the most maximized wind and wave shocks in the world. In a public announcement, she told the media that all buffer zones in all protected areas in the country shall also be revitalized into their natural state. She was also pushing for the establishment of numerous protected areas in the country such as the West
Panay Mountain Range National Park. She also announced that the UP Arboretum would be an ecological paradise where the informal settlers in the area will be the partners for its development. Her environmental policies were much criticized by some big business ventures and pro-mining lawmakers (her father owns one of the biggest companies in the country), but were backed by numerous environmental and human rights NGo's. In a recent survey, Filipinos backed Lopez's environmental policy by a huge majority. She was called a symbol and champion of environmental conservation in the country ever since. Lopez's appointment as Environment Secretary was rejected by the
Commission on Appointments (CA) in a vote of 8–16 on May 3, 2017, amid issues over her controversial policies and alleged incompetence. She was the second member of President Rodrigo Duterte's cabinet to be rejected by the Commission on Appointments following former
Department of Foreign Affairs Secretary Perfecto Yasay. In a press conference after the announcement of her rejection, Lopez thanked the eight CA members who "voted according to their conscience" and urged the legislators to look after the needs of the poor and not of big businesses. She said "it is unfortunate that business interest have in fact run the day." She added "if government co-opts to big businesses, then what hope does the poor have? What message are we giving here? If you wanna be confirmed, don't go against big businesses." ==Return to private sector and public activism==