The White House is proposing to slash a quarter of the U.S. Environmental Protection Agency’s budget, targeting climate-change programs and those designed to prevent air and water pollution like lead contamination, a source with direct knowledge of the proposal said on Thursday. President Trump has long signaled his intention to reverse former Democratic President Barack Obama’s climate-change initiatives. But the Republican president has vowed his planned overhaul of green regulation would not jeopardize America’s water and air quality.