seller disclosures - California

[Kathleen Brady]

Hi! Wondering if anyone can give me insight into seller disclosure requirements?  More specifically, should a seller have been required to disclose that the yard was full of hazardous materials? I bought a 2 family rental in Sacramento and turns out the yard is full of hazardous debris including lots of syringes and broken glass right under the topsoil. Since the seller did minor landscaping throughout the entire property, I can't help but assume they knew this was there. Do I have any recourse?