Alamitos Barrier Improvement Project - UPDATE Seal Beach Leisure World Community Meeting Clubhouse 2 August 31, 2016 Orange County Water District
Meeting Objectives Overview of OCWD Overview of the Alamitos Barrier Why we need to construct more monitoring and injection wells What happened behind the noise walls in the Clubhouse 2 parking lot, and what we learned Well construction project update OCWD contact information
Orange County Water District Formed in 1933, responsible for managing and protecting the OC groundwater basin Replenishes the basin for benefit of 19 retail water agencies in northern OC OC groundwater basin provides 70-75% of water for over 2.4 million people 10-member board of directors Internationally recognized
Two freshwater injection barriers protect Orange County from seawater intrusion. Alamitos Barrier Bixby Ranch Hill Landing Hill Bolsa Chica Mesa Talbert Barrier Huntington Beach Mesa Newport Mesa
The Alamitos Barrier has operated since 1964. SCWC-LAYT SB-LEI SB-BEV Long Beach LEISURE WORLD Seal Beach
OCWD is constructing 17 new injection wells to prevent intrusion through the barrier. SCWC-LAYT SB-LEI SB-BEV I Zone 2015 Chloride (mg/l) Feet 0 1,000 2,000??
Seal Beach Fault Saline groundwater is getting through parts of the barrier. A A' Injection Wells Production Wells SB GSWC Pacific Ocean C B A I Main Aquifer
San Gabriel River Seal Beach Blvd Existing monitoring wells inside Leisure World 7th St Production Wells LADWP 2nd St Westminster Ave
San Gabriel River Seal Beach Blvd 7th St New monitoring wells Production Wells LADWP 34V3 & PZ7 PZ9 2nd St Westminster Ave
Noise-reducing panels installed in Clubhouse 2 Parking Lot
Reverse-Circulation Mud-Rotary Drilling Method Shaker Table Drilled Cuttings Drill Column Pipe Trailer Drill Rig Mud Tank with Sediment-Removal Shaker Table Surface Conductor Casing Open Borehole Drill Column Pipe Drill Bit
Drilling Equipment Setup
Borehole Drilling 17½-inch diameter clawed-end drag bit Adding drill pipe to drill deeper
Borehole Drilling Collecting Drilled Cuttings Using a colander-like tool, Geologist collects the drill cuttings above the shaker table The shaker table separates the fluids from the solids. Gravel, sand, clay balls, wood chips or shells can appear
Lithologic logging Color and sediment type changes with depth; important in interpreting the hydrogeology.
Nested Monitoring Well 34V3 Construction Installing 4-inch diameter PVC casing Casing Depths #1: 185 feet [C-zone] #2: 225 feet [B-zone] #3: 280 feet [A-zone] #4: 345 feet [I-zone] Installing filter pack & low permeable seals between well screens
Shallow Well Drilling & Construction Geologist logs the soil cores, borehole depth 20 feet Drilled and constructed by hollow stem auger PZ9 Well casing inside subgrade vault
Monitoring & Sampling the New Wells Nested Monitoring Well 34V3 Sample for chloride and measure water levels 2-4 times per year Shallow Monitoring Wells PZ7 & PZ9 Measure water levels once a month 34V3 PZ7 34V3 PZ7
Seal Beach Fault West Pacific Ocean Initial Findings at Monitoring Well 34V3 Add Future Injection Well C B A 34V3 East I Main Aquifer
Depth to Water (feet) Shallow Wells Water Levels 0 Ground Surface 5 PZ9 (Golden Rain Rd) PZ9 [Golden Rain Rd] PZ7 [CH2 Parking Lot] 10 15 PZ7 (CH2 Parking Lot) 20 July August September
Well construction along Los Alamitos Channel
Los Alamitos Channel
Wells completed to date Los Alamitos Channel
Highly Constrained Work Area Leisure World Residences Proposed Well
Construction along Los Alamitos Channel 24-hour operation, including some weekends Well construction completion: Fall 2017 Temporary noise walls installed Injection well equipping (vaults, piping, valves) after all wells are constructed Days only Completion Spring 2018
Noise-reducing panels installed on the Channel roadway View from Mutual 3 View from Mutual 8 Sound walls on the north end of Channel
Drilling & Well Construction on the Channel
Fact Sheet and OCWD contact information Project Fact Sheet (hand-out) OCWD contact information: Construction hotline: (714) 378-8244 Email: info@ocwd.com
End of Presentation Questions?