This week I have read and debated about tailings disposal in the desert. That set me in mind of a paper I wrote more than twenty years ago. It is fun to go back and see what was in issue then as compared to now. Here is the link to the paper with the long title Remedial Activities in Arid Areas: The Design of Hazardous Waste Cells in the Desert. Some of what we wrote then is now out-of-date, but a surprising amount is still valid. Because it is Friday, the sun is shining, and my bike beckons, I say no more than invite you to download it and contemplate the passage of time and the developmen of knowledge. A good weekend.