Rancho Murieta Sewage Treatment Plant Expansion Phase I

For the Rancho Murieta Sewage Treatment Plant expansion, Youngdahl evaluated soil conditions at a borrow area and at the project site to determine the adequacy of the materials for embankment construction and impervious lining materials. As part of our geotechnical work, falling and rising head permeability testing was performed on the on-site native material.

Rancho Murieta Water Treatment Plant Expansion Phase III

Youngdahl conducted a geotechnical engineering study for the proposed Rancho Murieta Water Treatment Plant, Phase III. The proposed expansion consisted of four to five single-story support structures, several sedimentation and flocculation basins, and two sludge drying ponds. The study was to explore and evaluate the surface and subsurface soil conditions at the site and to develop geotechnical information and design criteria for the proposed plant.  The scope included:

• A field study consisting of a site reconnaissance, characterization of the soil and groundwater conditions at the site, and an exploratory soil boring program to formulate a description of the subsurface conditions.

• A laboratory testing program performed on representative samples collected during our field study.   

• A review of available published and unpublished geotechnical and geologic data pertinent to the project site. 

• Engineering analysis of the data gathered during our field study, laboratory testing, and literature review.  Development of recommendations for site preparation and grading, and geotechnical design criteria for building and storage tank foundations, underground installations, retaining structures, and slab-on-grade construction.

• A report summarizing our findings, conclusions, and recommendations regarding the geotechnical aspects of the project site.

• This report summarizes the results of our study, together with the above recommendations and design criteria.

Geotechnical Engineering Study Of The Pond 4 Embankment

The Rancho Murieta CSD asked Youngdahl to conduct a site reconnaissance and subsurface investigation on suspected seepage from the downstream slope of the wastewater treatment plant’s Pond 4 embankment. Youngdahl provided the following services:

• A Geotechnical Subsurface Field Study,

• Geologic Engineering & Hydrogeologic Analysis,

• Engineering Analysis

• Preliminary Reporting

We evaluated the surface and groundwater elevation, general water chemistry, and weir flow data provided daily. The CSD was able to initiate a repair program after Youngdahl’s study confirmed that there was indeed seepage when the water level was near capacity.

Main Photo Credit: Town and Country Real Estate