Public Participation Grant No. G1000328 (2009-2011)
Edmonds Citizens’ Awareness Committee,
Brackett’s Landing Foundation
PPG PROJECT EVALUATION REPORT
UNOCAL EDMONDS SITE
UNOCAL operated a Bulk Fuel Terminal in Edmonds, Washington from 1923 to 1991. In addition to the large volumes of various fuels handled at this site for almost 70 years, an asphalt plant was also in operation at the site for about 20 years. The site is located near Puget Sound, adjacent to Willow Creek and the Edmonds Marsh. A fish hatchery is also located at the southeast corner of the property.
The UNOCAL Edmonds site includes an Upper Yard where storage tanks and distribution piping were located and a Lower Yard with offices, rail and truck loading facilities, the asphalt plant and associated warehouse, and storm water handling facilities (Detention Basins 1 and 2). After extensive excavation of contaminated soils, the Upper Yard was sold and is now a residential condominium development. The Lower Yard has been identified for use as a multimodal transportation hub, including relocation of the Edmonds ferry. A purchase and sale agreement for the Lower Yard has been completed between UNOCAL (since purchased by Chevron) and the Washington State Department of Transportation (WSDOT). Due to budget constraints, the schedule for development of the multi-modal transportation hub, known as Edmonds Crossing, has been delayed.
Site characterization studies of the Lower Yard documented extensive contamination of soils and ground water with TPH and related contaminants. Floating product (LNAPLs) was also detected at multiple wells over large portions of the Lower Yard. After early attempts to recover LNAPLs, a series of Interim Actions began in 2001 and included excavation and removal of contaminated soils, removal and treatment of contaminated ground water, and product removal in localized areas of the Lower Yard. The large Detention Basin 1 was also dewatered and cleaned out. During 2007-2008 an extensive Interim Action covering most of the Lower Yard was undertaken, intended by Chevron to complete active site remediation. A post-Interim Action two-year ground water monitoring program started in October 2008. Ground water chemistry was monitored at 40 wells to track compliance with ground water cleanup levels at the property boundary (the MTCA point of compliance), determine if remaining ground water contamination within the Lower Yard was naturally attenuating, detect any re-occurrence of LNAPLs, and determine if residual soil contamination was adversely affecting ground water quality.
The ground water monitoring program was originally intended to include 13 rounds of sampling and analysis of ground water (every two months from October 2008 through October 2010). The monitoring program was modified midstream to a quarterly schedule, to include only 11 rounds over two years. Ground water monitoring is continuing on a quarterly basis after completion of the planned two-year post-Interim Action monitoring program. As of June 30, 2011, data from a total of 12 rounds of sampling are available to track trends in ground water quality following completion of recent Interim Actions. Based on results to date, Ecology issued a Determination Letter on May 27, 2011 stating that the 2007-2008 Lower Yard Interim Actions do not constitute final cleanup actions for the Lower Yard. As a result, Chevron will prepare a Feasibility Study to identify and evaluate alternatives for additional cleanup actions. After the Feasibility Study is completed, Ecology will prepare a Cleanup Action Plan.
PUBLIC PARTICIPATION GRANT HISTORY
Reflecting community interest and concerns regarding cleanup of the UNOCAL Terminal Site, the Brackett's Landing Foundation established the Edmonds Citizens' Awareness Committee (ECAC) to support citizen involvement in the cleanup process. Brackett's Landing Foundation has applied for and received a series of Public Participation Grants from Ecology, starting in 1995. Those grants have allowed ECAC to hire its own technical consultants to review site information, provide technical review comments to Ecology, and help educate the community about site contamination issues. The grants have also supported citizen participation in the extended MTCA cleanup process, so that Ecology can take community interests into account.
The formal cleanup process at the UNOCAL Edmonds site started in 1993 when Ecology and UNOCAL signed an Agreed Order for completion of a Remedial Investigation and Feasibility Study. The time needed to complete site cleanup has far exceeded what was foreseen when ECAC received its first grant in 1995. Ecology has provided ongoing community support through continuation grants as the cleanup process has been repeatedly extended. ECAC has applied for a continuation grant for 2011-2013 to continue oversight of the ground water monitoring program, support independent technical reviews of the Feasibility Study (including further site characterization studies to address data gaps) and Cleanup Action Plan, and educate citizens through ECAC’s website.
CURRENT GRANT ACTIVITIES
Monitoring of Site Cleanup. The planned Lower Yard Interim Actions - which included extensive soil excavations, LNAPL removal, removal and treatment of large volumes of ground water, and backfilling of the Lower Yard – were completed in the second half of 2008. No additional physical cleanup actions occurred during the 2009-2011 PPG period. By agreement between Chevron and Ecology, a two-year program for monitoring ground water throughout the Lower Yard and along the property boundary (the MTCA Point of Compliance for ground water cleanup) was instituted after the 2007-2008 Interim Actions. The status of ground water quality in comparison to established site ground water cleanup levels was to be tracked over this monitoring program (see below). If ground water conditions had improved and could be shown to be in compliance with the cleanup standards, the Interim Actions could have been considered final cleanup actions. By the end of the ground water monitoring program it was clear that this was not the case. The process to complete a Feasibility Study and a Cleanup Action Plan was therefore initiated before the end of the 2009-2011 grant period. Chevron announced that there would be no further Interim Actions at the site before a final Cleanup Action Plan was developed. Absent further Lower Yard cleanup actions during this grant period, ECAC’s activities focused on the ongoing ground water monitoring program. ECAC and its consultant visited the site on two occasions (October 2009 and April 2010) to observe ground water sampling activities. Ecology’s Blake Nelson, PPG program staff, met with ECAC at the site in October 2009 and was provided with a site briefing.
Review of Site Reports. ECAC reviewed and provided technical comments on several reports during the current grant period. Documents reviewed included the following:
- Phase II Lower Yard As-Built Report (May 13, 2009). Review comments were submitted to Ecology on July 21, 2009.
- 2009 Annual Groundwater Monitoring Report (February 12, 2010). Review comments were submitted to Ecology on April 19, 2010.
- 2010 Annual Groundwater Monitoring Report (January 25, 2011). Review comments were provided to Ecology as a document markup on May 20, 2011.
- Aquifer Testing Work Plan (January 25, 2011). Review comments were discussed with WSDOT’s consultant (Landau Associates) and Ecology.
In addition, ECAC received copies of Chevron’s monthly progress reports as submitted to Ecology. The results for each round of ground water sampling were attached to these monthly progress reports and formed the basis for ECAC’s ongoing review of the ground water monitoring program and site ground water status.
Meetings. ECAC met periodically with its technical consultant to discuss the status of site cleanup activities, evaluations of recent sampling results, and plans for community updates via the weblog. Ecology, Chevron and its consultant ARCADIS, and ECAC, along with WSDOT and its consultant (Landau Associates), continued the cooperative approach established earlier through the Technical Work Group to identify and discuss issues as they arose. ECAC participated in meetings with this group at ARCADIS’ offices in Seattle on three occasions during the grant period: October, 2009; November, 2010; and May, 2011. At these meetings, review comments and technical issues for several site reports (see above) were discussed, cumulative ground water monitoring data were reviewed, and the status of the site and schedules for future activities were discussed.
Long-Term Ground Water Monitoring Program Data Reviews. The post-Interim Action two-year ground water monitoring program started with round 1 sampling in October 2008. A total of 40 wells was sampled and analyzed each round, with additional wells observed for ground water elevations and product occurrence. During the current grant period results from sampling rounds 5 through 11 of the planned two-year program were reported by Chevron (as attachments to monthly progress reports to Ecology). The first round of additional sampling from Q1 2011 was also completed. ECAC reviewed the results from each round as they were reported and prepared summary reports to be posted on ECAC’s website (see below). Time trend plots were prepared for selected sets of wells to visualize and track trends in ground water TPH concentrations; those time trend plots were periodically posted on the website. At the completion of the planned two-year post-Interim Action ground water monitoring program, TPH results were summarized by sampling round (n=11) and by monitoring well (n=40) in a set of tables to provide an easily accessible overview of ground water quality status at the site. Those summary tables were also posted at the website. A number of patterns were observed in the two-year data set. Some wells, mostly within the interior of the Lower Yard, showed progressive decreases in TPH concentrations over time; by the end of the two-year period, few interior wells exceeded cleanup levels. A subset of the perimeter (point of compliance) wells showed consistent exceedances of cleanup levels over time, with several having non-decreasing or even increasing TPH concentrations. Those trends are difficult to reconcile with natural recovery processes and may indicate ongoing TPH sources. Another subset of wells showed marked “up-and-down” patterns in TPH concentrations over time, with low TPH levels at a point in time followed by exceedances of cleanup levels in later rounds. Short-term results at such variable wells are thus not necessarily indicative of longer-term compliance. Petroleum product (LNAPLs) has been consistently observed at one perimeter monitoring well, MW-510, located near the former asphalt plant “slops pond”.
Weblog. During the previous grant period, ECAC established a website (www.ecac-unocal.org) as a primary means of keeping the community informed about the status of site cleanup, issues needing resolution, and opportunities to participate and comment on the overall cleanup process. By June 30, 2011 there have been more than 3,000 hits on this blog site. The results of 8 rounds of ground water sampling, occurring between June 2009 and March 2011, were reported during the current grant period. After each round’s results were reviewed, summary information was posted on the ECAC website. Additional information posted included time trend plots of TPH concentrations at wells, an example calculation of time-to-compliance based on exponential decreases in TPH concentrations over time, summary tables of TPH exceedances of cleanup levels by round and by well, copies of technical review comments submitted by ECAC for various site reports, site status and schedules information discussed at technical Work Group meetings, and the 2007-2009 PPG Evaluation Report. The website also includes a map showing the Lower Yard and all monitoring well locations and a set of historic airphotos of the UNOCAL Edmonds site and its surroundings. Ecology’s Determination Letter of May 27, 2011, stating that the 2007-2008 Interim Actions were not final cleanup actions and including a list of key issues for site ground water, was also posted on the website to communicate the latest information on site status. A preliminary anticipated schedule for completion of a Feasibility Study and Cleanup Action Plan, suggesting that further cleanup activities would not occur before 2014, was also noted on a website posting.
SITE STATUS AS OF JUNE 30, 2011
Attempts at floating product (LNAPLs) recovery in the Lower Yard date back to 1987. After a series of more limited and localized cleanup actions, the 2007-2008 Interim Actions completed an extensive excavation program to remove contaminated soils, while also removing free product and removing and treating a large quantity of contaminated ground water during excavation dewatering. The excavation areas and volumes of soils removed were considerably larger than identified during planning of the Interim Actions, based on site characterization information. Buried drums with product and assorted debris were found buried in the southeast Lower Yard, an area without significant historic operations associated with Bulk Fuel Terminal operations.
Some TPH-contaminated soils remain in the Lower Yard, including soils with TPH below the selected remediation level of 2,975 ppm, a few locations with TPH levels marginally above that remediation level, and more substantially contaminated soils near the WSDOT storm drain line. It is also possible that one or more areas with elevated TPH concentrations have not yet been detected (as substantial portions of the southeast Lower Yard were not identified before excavations began).
The post-Interim Action ground water monitoring program has identified continuing TPH contamination above cleanup levels at multiple locations across the Lower Yard. One well, MW-510 located near the former slops pond adjacent to the asphalt plant, has repeated observations of LNAPLs presence. Approximately one-third of the perimeter (point of compliance) monitoring wells, at multiple locations along the property boundary, exceed the TPH cleanup levels for the site, and several of those have non-decreasing or increasing concentration trends. Ground water flow directions are outward from the property boundary, suggesting some degree of continued offsite migration of ground water contamination, some 20 years after site operations ended in 1991. The non-decreasing TPH trends at some wells, as well as the presence of LNAPLs, suggest that there may still be some uncontrolled sources of petroleum contamination at the site which could result in a prolonged duration of ground water contamination. The “up-and-down” trends in TPH concentrations at several wells, including at least one well in the interior of the Lower Yard, still need to be understood, especially with respect to seasonal effects of ground water elevations and remaining sources. In general, ground water in the interior of the Lower Yard has lower TPH concentrations compared to those perimeter wells with elevated levels.
Ecology has determined that a Feasibility Study needs to be completed for the Lower Yard to identify and evaluate alternatives for further cleanup actions. Chevron has begun the steps needed to prepare that report. It is likely that additional site characterization information will need to be collected to address data gaps and support completion of the Feasibility Study. Ecology will prepare a Cleanup Action Plan by 2013, which will be released for public comment. Final cleanup actions are now deemed likely to occur in 2014. The Draft Work Plan for the Feasibility Study is scheduled to be submitted to Ecology in August 2011. Ecology expects to complete its review of that Work Plan by the end of 2011.
With further PPG support from Ecology, ECAC intends to continue to review all ground water monitoring data, the Draft Feasibility Study and Draft Cleanup Action Plan, and all additional site characterization results, and to inform the community through ECAC’s website and encourage citizen participation in the cleanup process.