Laudric, which operates car washes, has for six years published on its website an "environmental charter" undertaking to treat the polluted sludge of its former stations, which it has always done. At 31 December 20X5, three stations closed during the year contain sludge; in addition, management is considering installing new retention tanks in 20X6 in the stations still open, with no legal obligation. Write a memo analysing the obligations to be provided for, distinguishing the rules of the standard, the case data and judgement.