Locals and tourists alike have made the 'Trash Hero' campaign on Koh Lipe a great success, with copycat initiatives spreading throughout Thailand and even Indonesia 
 

Every Monday is a special day on Koh Lipe, a sandy, breathtaking and increasingly touristy Andaman island off Satun province. It's the day when everyone, locals or visitors, can call themselves a hero. 

Since December 2013, Monday has been designated as the day of the "Trash Hero", when a big clean-up of Koh Lipe, including other small islets in Moo Koh Adang Rawi in Tarutao National Marine Park, takes place with the participation of locals and tourists. Fifteen months after the campaign began, it is estimated over 50 tonnes of garbage have been removed. 

"Trash Hero" won The Thailand Green Excellence Awards UK in November 2014. The campaign has gradually become an inspiration for other tourist spots in Thailand, and even Indonesia. 

http://www.bangkokpost.com/lifestyle/social-and-lifestyle/599752/cleaning-up-the-accolades