Fast-growing Shantou has been warned it risks losing its status as one of Guangdong's six 'environmental model cities' after failing to meet green benchmarks. The State Environmental Protection Administration (Sepa) has given the Pearl River Delta city until the end of next year to meet its standards for economic sustainability, waste water treatment, ratio of greenery to developed areas, household waste disposal and progress towards a comprehensive pollution-control plan, the Southern Metropolis News reported. As well as failing Shantou on these five factors, Sepa, in an evaluation two months ago, said the city had provided inadequate information to grade it on another four factors out of a total of 27. In their defence, city officials said Shantou had grown in size from 310 sq km to nearly 2,000 sq km when administrative boundaries were redrawn two years ago. The three districts absorbed had contained backward suburbs, they told the Guangzhou-based daily. The paper quoted a Sepa official as supporting this explanation. He said Shantou would have passed November's examination had its area not been enlarged. City officials are determined to keep its green status, which it shares with 43 others across the mainland. At an emergency meeting on Thursday, a day after receiving Sepa's ultimatum, they vowed to launch a cleanup.