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 he Sparks Solvent/Fuel Site (SSFS) is a railyard and fuel terminal tank farm located in Sparks, Nevada. Industrial activities at the site over the past century led to contamination of groundwater and soils by gasoline, solvents, diesel fuels, and other petroleum products. This webpage presents an overview of the site and provides information on the current status of the site investigation and cleanup.
History of the Sparks Solvent/Fuel Site
The railyard was constructed in the late 1800's and has served as a major east-west thoroughfare for railroad traffic since its construction. Before the 1950's, the railyard was the largest industry in Sparks, with a roundhouse, powerhouse, machine and locomotive shops, crew lodging and commissary. Current and past railyard operations include maintenance, cleaning, refueling, and storage of railroad engines and other rolling stock.
The site has been used as a refueling and service area for Southern Pacific Railroad since about 1907 and has been a fuel storage and distribution facility since 1957. Current and past operations at the terminal include the storage, distribution, and loading of gasoline, heating oil, diesel fuels, military fuels, and fuel additives.
In 1991, the terminal and railyard landowners and tenants began coordinated remediation and monitoring at the site through the Vista Canyon Group. The Vista Canyon Group includes the following entities:
- Berry-Hinkley Terminal, Inc.
- Chevron USA, Inc.
- Equilon Enterprises LLC, a joint venture between Shell Oil Company and Texaco Refining and Marketing, Inc.
- Kinder Morgan Energy Partners, L.P. through its operating partner SFPP, L.P. (formerly Santa Fe Pacific Pipelines, Inc.)
- Union Pacific Railroad Company (formerly Southern Pacific Transportation Company)
- Time Oil Co.
- Union Oil Company of California, d.b.a. UNOCAL
Current Status of Site
The water level of the Sparks Marina Park Lake controls the local hydrology, including water levels and flow directions of groundwater underlying the SSFS. Groundwater underlying the SSFS flows toward the lake and would ultimately discharge in the lake unless intercepted. Protection of the lake from contaminated groundwater is a major objective of the SSFS remediation system. The pump and treat remediation system currently contains and remediates contaminated groundwater at the SSFS.
The plume of contaminated groundwater is being hydraulically contained by two "fence lines" of extraction wells ("M" and "P" wells), so the contaminants do not pose a threat to the Truckee River, the Sparks Marina Park Lake, groundwater supplies, or local water sources. Monthly testing is conducted on the treated groundwater (that is, effluent from the remediation system) to ensure contaminants are not being discharged to the Truckee River.
Monitoring wells across the site are sampled annually or semi-annually to provide the concentration data needed to evaluate and monitor the extent and behavior of contaminants in groundwater; water-level measurements are also collected from the monitoring wells.
Groundwater monitoring reports and remedial system reports are submitted semi-annually to the NDEP for review. Concentrations of contaminants have generally decreased over the period of remedial action (see Table 1).
Investigation During 2006 and 2007
Recent work at SSFS has included continued groundwater and remediation systems monitoring, with groundwater monitoring following the revised schedule for long-term monitoring plan (see NDEP letter of November 16, 2006). Recent documents include the 2006 Annual Monitoring Report (January 2007), quarterly Remediation System Reports, completion of a human health risk assessment (April 2007), and NDEP concurrence with a Multi-Level Sampling Work Plan (November 2007).
The purpose of the multi-level sampling is to evaluate whether site contaminants have migrated into the deeper zones of the regional shallow aquifer. Water-supply wells for the Truckee Meadows Water Authority (TMWA) are screened at various depths, with the nearby Stanford Well first screened at 215 to 250 feet bgs. Contaminants such as MTBE and PCE have been detected in other TMWA water-supply wells. Although the sources of these contaminants are not well defined, their presence in the deeper portion of the potable water aquifer indicates that there is hydrologic communication between the shallow and deeper (water-supply) zones of the regional aquifer.
The goal of the multi-level sampling is to evaluate lithology and contaminant concentrations in the lower part of the aquifer, which contains more clay-rich zones than the upper portion (0 to 100 feet bgs) of the aquifer. Five borings will be drilled to approximately 150 feet bgs at selected locations across the SSFS. Groundwater samples will be collected at multiple depths from within each boring, and analyzed for chemicals of concern.
 Sparks Solvent/Fuel Site -- Administrative Record 2006-2007
Plume Map of MTBE Concentrations in Shallow Groundwater at SSFS, Fourth Quarter, 2001.
Geologic Cross Section across the SSFS (East-West trace, looking north)
For additional "historic" information see the SSFS Archive Website
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