Hearst Castle Neptune Pool Renovation Project


The iconic Neptune Pool at Hearst Castle in San Simeon, California embarked on a complete restoration project nearly three years ago. The restoration and renovation project included completely draining the pool, carefully removing and storing the ancient statues that adorned the perimeter of the pool, removing all of the old tile, finding and repairing leaks in the system, sealing the concrete shell, updating the filtration, piping and flow systems, adding waterproofing, resurfacing the pool and installing about 10,000 replica white marble tiles and 4,500 green serpentine tile pieces. Dozens of different industry experts were included in this project to preserve the historical accuracy, restore the artifacts, and integrate modern plumbing systems into a historical pool.

A-Tech Consulting at Neptune Pool Project

For over 10 months, A-Tech Consulting was part of the renovation and restoration project for the Neptune Pool serving as the environmental consultants.

Neptune Pool History

According to HearstCastle.org, the Neptune Pool was originally constructed in the 1920s, designed by William Randolph Hearst. The Neptune Pool is built above ground, lined with marble and serpentine tiles. The pool is 104 feet long, 58 feet wide and 95 feed wide at the alcove. It takes around 350,000 gallons of water to fill the pool.

In 2014, the nearly 90-year-old pool was drained due to cracks that caused it to leak up to 5,000 gallons a day. Construction work begun in 2016 and renovations were completed in August 2018, where the process of refilling the pool finally began.

Did You Know … The state rock of California is serpentine. One of the primary serpentine minerals is chrysotile. Chrysotile is white asbestos.

Therefore … Serpentine = asbestos.

Restoration Project

In order to obtain a close to identical match of the original green marble tiles in the pool, they purchased new green marble tiles from the exact same location where the original tiles were purchased nearly 100 years ago – a stonework quarry in Vermont. However, due to the color and the historic nature of the material, there was NOA (naturally occurring asbestos) in the tiles and this is where A-Tech Consulting was retained for occupational and environmental exposure compliance for asbestos related work activities.

Neptune Pool Construction

A-Tech Consulting was hired to train skilled tile workers how to work with NOA, properly use personal protective equipment, properly assemble and utilize a containment and institute proper engineering controls. A-Tech Certified Asbestos Consultants and Technicians, conducted personal monitoring for the contractors who were doing the green marble tile cutting for the Neptune Pool.  A-Tech was hired to conduct oversight to ensure the contractors and general public were not exposed to any asbestos fiber concentration above the Permissible Exposure Limit (PEL). We conducted personal air monitoring, using PCM cassettes attached to the workers suit as they were filing and shaping the green marble tiles.  Additionally, we conducted daily air monitoring around the entire work site.  There was a lot of technical logistics throughout the phases of the project that our expert staff was able to create cost and time efficient solutions for.  This project will be a company favorite; being trusted with such a sensitive and complex project as a participant in a historical project in a beautiful location in the Central Coast is a huge testament to expertise and responsiveness of our team.