Kleinfelder - Hunter's Point Groundwater Monitoring

Projects / Federal Government / Hunter's Point Groundwater Monitoring

Hunter's Point Groundwater Monitoring

Hunters Point Naval Shipyard
San Francisco, CA

Project Description:

In November 2003, the U.S. Navy retained Kleinfelder to implement the required base-wide groundwater monitoring at the Hunters Point Naval Shipyard in San Francisco, California. This program involves quarterly sampling of 235 groundwater wells and collecting water level measurements at 442 groundwater wells. Sampling data that is generated on this project undergoes a 20% Level IV data review by LDC, Inc. while the remaining 80% receives Level III validation.

To date, approximately 98% of our data has been successfully validated. Kleinfelder compiles the validated data into the Navy's project database, and then manipulates the data for quarterly and annual reports. The data is evaluated and used to generate iso-concentration plots and water level contour plots using a GIS interface. In addition, Kleinfelder further evaluates the data for optimization of remediation and for cost saving possibilities.

Kleinfelder has supported several innovative approaches to monitoring to reduce long-term costs. The project has evolved to the use of low-flow sampling, flow through cells and a central sample processing center. Low flow sampling per ASTM standards is used during the purging of monitoring wells; crews purge the well at 200-500 milliliters per minute using the latest Grundfos stainless steel pump and controller technology. Low flow purging and sampling allows a pump to be set within the screened interval of a well and allows fresh water to enter from the surrounding aquifer without disturbing the stagnant column.

While purging at low flow rates, crews take continuous readings using a Horiba U-10 multi-meter submerged in a flow-through cell. The meter measures turbidity, pH, conductivity, dissolved oxygen, temperature, and salinity on an easy to read handheld display. Once the various parameters stabilize, samples are collected by the field crews and brought to a central sample processing location. The sample processing location performs a quality check for correct number and types of bottles, logs each sample onto a chain of custody, then packages the samples for shipment to APPL laboratory.

Client Benefits

To date, this project has sampled nearly 1,000 wells filling 340 coolers with 8,000 sample containers, with every cooler being delivered within temperature requirements and with only one broken bottle (an extra bottle that did not require re-sampling of the well). Project requirements include extensive documentation. Monitoring reports are frequently over 1000 pages in length. Reports have been prepared nearly error-free resulting in very few comments going from draft to final.
Due to the large number of wells and samples for this project, previous contractors have experienced a significant percentage of quality control issues. Kleinfelder solved these problems by implementing unique sample processing and data management procedures. Procedures have produced a high level of both efficiency and accuracy, managing thousands of sample containers while maintaining sample integrity.
Kleinfelder has implemented extensive field quality control (QC), including internal audits of the sampling crews and several types of field and laboratory QC samples. Data management involves an external data validation process, maintenance of several databases, and implementation of strict QA/QC protocol. The greatly improved performance implemented by Kleinfelder has prompted the client to extend Kleinfelder's activity at the site in both time and scope.