SAN DIEGO (CBS 8) - Lakeside residents railed against a proposal to excavate part of the El Monte Valley at a packed planning group meeting Wednesday evening. 

Opponents of a plan to mine millions of pounds of sand from the area over a period of 15 years said it would destroy the natural beauty of the valley, as well as take away miles of horse trails that equestrians use on a daily basis. 

The company behind the plan, the El Monte Nature Preserve, promised to work with the community, and provide alternate riding trails while the excavation work was underway.