Stanislaus County is planning an event in October for collection of old pesticides that are stored on farmers’ properties. The Board of Supervisors gave approval Tuesday evening to hold the four-county Pesticide Takeback Disposal event Oct. 11-13. The county agricultural commissioner’s office is organizing the state-funded event with Merced, Tuolumne and Mariposa counties. … Storage of chemicals in older containers raises safety issues and can lead to environmental harm. Improper storage “increases the likelihood of containers breaking down and leaking” and “release of pesticide concentrates into the environment can (result in) harming people, wildlife, water supply and the environment,” a county staff report said.