<prompt> Translate the following text to EnglishKwa mfano, RCED ilichunguza maendeleo yaliyofanywa tangu miaka ya 1970 katika kusafisha hewa, maji, na ardhi ya taifa, na kugundua kwamba wakati hatua zilikuwa zimetolewa kuelekea kufikia malengo yaliyowekwa hewa safi, maji taka yaliyotengenezwa vizuri, maji zaidi ya kunywa, tarehe za mwisho zilikuwa zimepanuliwa na masuala yasiyosuluhishwa yalifanya kukutana hata na tarehe hizi za mwisho kuwa ngumu.  <response>: In 1982, for example, RCED examined the progress made since the 1970s in cleaning up the nations air, water, and land, finding that while strides had been made toward meeting the established goals cleaner air, properly treated wastewater, more drinkable water, deadlines had been extended and unresolved issues made meeting even these deadlines difficult U.S. 