Arsenic Removal Project

Lost Hills Water District, 
California

Arsenic Removal Project

Service Type: 
Project Highlights: 
  • Evaluation of IX, AA, C/F, EDR and RO arsenic removal processes.
  • Preliminary capital and O&M costs for C/F process.
  • Preparation of financial tables and detailed information as required for a USDA Rural Development grant/loan.
Lost Hill facility site
Carollo developed process schematics and costs for the 1.4-mgd facility at Lost Hills Utility District.

Carollo was retained by the Lost Hills Utility District to evaluate feasible arsenic treatment processes and prepare documents necessary for the United States Department of Agriculture (USDA) funding review process. The District draws groundwater from one location containing arsenic at relatively high levels, often approaching the current arsenic Maximum Contaminant Level of 50 ppb arsenic. Groundwater is relatively clean with minimal amounts of compounds that can interfere with arsenic removal processes (e.g., sulfate). However, a raw water pH level of 9.5 does present a treatability concern that will likely result in increased treatment costs. By a desktop analysis, it was determined that a coagulation/filtration process would remove arsenic at less than $1.00 per gallon when complete.