Disk Cleanup can be automated for regular silent cleanups. Physical cleanups of oil spills are also very expensive. The volunteer group organizes park cleanups and improvement events. Environmental groups have pressured state regulators to begin forcing cleanups. Gloves, litter grabbers and refreshments may occasionally be provided at these cleanups. The cleanups occurred primarily in residential areas of Dayton. They may organise litter collections or "best kept village" cleanups. Occasional cleanups and crack downs satisfied the demands for reform. Volunteer cleanups aided by the Corps of Engineers began in 2010. Other cleanups have taken place along the Hudson River and San Francisco Bay. The organization hosts annual cleanups in the summer. I* with GL/EL, although a number of detail cleanups improved range and accuracy. The vast majority are shorter-term cleanups that are not listed on the NPL. Earth Day cleanups have been held globally since 1970.