Conditional Use Permit No. 25-05 (Thomas Bros. Gypsum Sales)

The applicant is proposing to establish gypsum storage and sales as a soil amendment at an existing composting facility located at 20111 Excelsior Ave., Riverdale, Assessor’s Parcel Number 004-062-003. The facility proposes to store up to 30,000 tons of gypsum during peak season (9 months) and up to 10,000 tons during off peak season (3 months). During the peak season, approximately 20 trucks per day are anticipated, which could increase to 30 trucks per day in the future. The facility will operate six (6) days a week during the peak season with approximately 4,676 truck trips, which could increase to 7,015 trips in the future. Gypsum will be stored in a designated area on site to prevent dust generation, contamination, and runoff. This storage area will be managed in compliance with air quality and stormwater control regulations to minimize environmental impacts. The enriched compost will be sold to local farmers, providing them with a high-quality, affordable soil amendment that supports healthier crop yields and sustainable farming practices. The facility’s operations ensure that gypsum sales will not interfere with existing composting activities or create significant additional impacts on traffic, noise, or air quality.