A Sonoma County-based environmental group with a litigious history is suing Lunny Grading and Paving and has announced its intention to file suit against Drakes Bay Oyster Company, both over alleged violations of the Clean Water Act. 

River Watch, which has sued or threatened to sue 20 local governments or private businesses in 2013 over violations mostly of that federal law, claims the oyster farm is disposing of shells, unwanted shellfish, shellfish parts, bleach, ammonia,…