1974 and 1975 concern came to focus on uranium mining in Australia and several Friends of the Earth groups were formed. The Australian Conservation Foundation also began voicing concern about uranium mining and supporting the activities of the grass-roots organisations. Concern about the environmental effects of uranium mining was a significant factor and poor management of waste at an early uranium mine, Rum Jungle, led it to become a significant pollution problem in the 1970s. The Australian anti-nuclear movement also acquired initial impetus from notable individuals who publicly voiced nuclear concerns, such as nuclear scientists Richard Temple and Rob Robotham, and poets Dorothy Green and Judith Wright. However, the main public audience was informed by well qualified senior scientists such as Sir Ernest Titterton and Sir Philip Baxter as detailed in the Book "The Nuclear Knights" by Brian Martin (1970). In 1975, Moss Cass, Minister for the Environment and Conservation, led parliamentarians and ALP branch members in expressing concerns about the effects of uranium mining. A key concern was the adverse effect that uranium mining would have on the northern Aboriginal people. Cass said: "nuclear energy creates the most dangerous, insidious and persistent waste products, ever experienced on the planet". The years 1976 and 1977 saw uranium mining become a major political issue, with the Ranger Inquiry (Fox) report opening up a public debate about uranium mining. Several groups specifically concerned with nuclear issues were established, including the Movement Against Uranium Mining (founded in 1976) and Campaign Against Nuclear Energy (formed in South Australia in 1976), cooperating with other environmental groups such as Friends of the Earth (which came to Australia in 1975) and the Australian Conservation Foundation (formed in 1975). In November and December 1976, 7,000 people marched through the streets of Australian cities, protesting against uranium mining. The Uranium Moratorium group was formed and it called for a five-year moratorium on uranium mining. In April 1977 the first national demonstration co-ordinated by the Uranium Moratorium brought around 15,000 demonstrators into the streets of Melbourne, 5,000 in Sydney, and smaller numbers elsewhere. A National signature campaign attracted over 250,000 signatures calling for a five-year moratorium. In August, another demonstration brought 50,000 people out nationally and the opposition to uranium mining looked like a potential political force. In 1977, the National Conference of the Australian Labor Party (ALP) passed a motion in favour of an indefinite moratorium on uranium mining,