Health Topics > Sierra-Crete Task Force
Sierra-Crete Task Force
September 27, 2002
Task Force Members
Present: Ron Bernal, City of Antioch; David Berry, California Department of Toxic Substances Control; Tim Bingman, DuPont; Brian Bornstein, City of Brentwood; Dr. Wendel Brunner, Contra Costa Public Health Director; Julie Bueren, Contra Costa Public Works; Brenda DeLaOssa, staff to Donna Gerber, Contra Costa Supervisor District III; Tim Farley, staff to Federal Glover, Contra Costa Supervisor District V; Annette Guiseppi-Elie, DuPont; Sara Hoffman, Contra Costa Office of the County Administrator; Devra Lewis, Central Valley Regional Water Quality Control Board; Walter Pease, City of Pittsburg
Absent: Steven Carmichael, City of Oakley; Martha Harnly, California Department of Health Services;
Staff: Michael Kent, Contra Costa Health Services
Members of the Public: Stefan Edelbacher, City of Antioch Resident; Bill Faisst, Brown and Caldwell; Kay LaCour, Cooper, White & Cooper; John Pekala, Environ Corp; Brian Poyezdala, Antioch Press; Deborah Proctor, Exponent; Ben Strumwasser, Public Affairs Management;
Others Present: Greg Harvey, Contra Costa County Counsel's Office;
Dr. Brunner, Contra Costa Public Health Director, opened the meeting at 9 a.m.. Introductions were made and the agenda was approved as proposed.
2. Approval of the Minutes
The minutes of the July 26, 2002 meeting were approved with minor corrections.
3. Update on Action Items
a) Location of Roads where Sierra-Crete was Used
Julie Bueren, Contra Costa County Public Works Department, reported that they have completed mapping the unincorporated portion of the County and Oakley. They are coordinating with Pittsburg and Antioch to transfer their data to the map, and the map should be ready to put on the County's web site in a couple of weeks. They will also be able to put the locations of where samples were taken on the map.
Action Item: Contra Costa County Public Works Department will continue to coordinate the collection of this information and placement of it on the County's web site.
b) External Agency Review of the Risk Assessment Submitted by DuPont
David Berry, California Department of Toxic Substances Control, reported that his agency has completed their review of the risk assessment. Copies of their comments were distributed to those present. He will provide an electronic version so that it can be put on the County's web page. In sum, they felt the risk assessment requires some revisions, but the basic method and conclusions are sound. Their concerns were mostly that the risk assessment needed to better clarify how its conclusions were reached, and it needed to be more consistent with current DTSC guidelines for conducting risk assessments. He thought that when recalculated, the risks may be a little higher than originally thought, but not significantly so. In DTSC's comments on the addendum to the risk assessment, they addressed the surface water quality concerns, and determined that additional samples were needed at the school sites.
Michael Kent, Contra Costa Health Services, asked whether the risk assessment adequately took into consideration scenarios of children playing on roads and the subsequent exposure. Mr. Berry responded that these scenarios will be pulled out more clearly in the next version of the risk assessment.
Annette Guiseppi-Elie, DuPont, said they would start updating the risk assessment methodology based on DTSC's comments, so that it would be ready to apply to the new data when it becomes available next month. She also wanted to know if the California Office of Environmental Health Hazard Assessment and Department of Health Services would be reviewing the risk assessment methodology. Michael Kent said he would check on this.
Action Item: Michael Kent, Contra Costa Health Services, will put these comments on the web site and check to see if the other state agencies are going to provide comment.
c) Public Involvement and Outreach
Dr. Brunner, Contra Costa Health Services, reported that door hangers and letters intended to be distributed before sampling began were not completed in time, and since sampling needed to be conducted during relatively warm weather conditions, the sampling could not be delayed. However, a press release did go out to the media about the samples being taken.
The group then discussed what type of outreach would be needed when the results from the sample analyses are complete and when the risk assessment is complete.
Bill Faisst, Brown and Caldwell, felt that the risk assessment should contain an executive summary written for the general public. Tim Bingman, DuPont, felt the level of outreach needed would be dictated by what the results of the risk assessment are.
Ben Strumwasser from Public Affairs Management, felt it would be a good idea to update the County's web site to let the public know that additional samples have been taken.
The group reached concensus that no public mailing should be sent out now, but that when the new risk assessment is complete, the appropriate level and detail of mailings and public meetings should be determined and carried out. Tim Farley, Supervisor Glover's office, stressed that all information sent to the public needs to fully inform them without being alarmiStreet Brenda DeLaOssa, Supervisor Donna Gerber's office, thought that maybe a press release should be sent out know to let the media know the timing of the rest of the project.
The group then discussed a question raised to Michael Kent from a community resident. This resident heard that core samples were taken several years ago from affected streets by one of the builders, and wanted to know if the analytical results from those samples could be of any use now. The group determined that it was probable that dioxins weren't sampled for then and could not be sampled for now because of holding time restrictions. Also, because of quality control and chain-of-custody issues, any results taken were not likely useable now.
Steve Edelbacher, Antioch resident, came in towards the end of the meeting and wanted to know why the door hangers and letters weren't done. Dr. Brunner gave him the explanation previously provided. He also asked if Tee Pee Court was sampled. Dr. Brunner reported that it was not because when all the streets were evaluated, this street was not among the worst.
4. Review of the Sampling Plan (discussed before item 3)
John Pekala, Environ, reported that the sampling plan was agreed to by the sampling subcommittee in early September. The sampling team consisted of Paul Andrews, Contra Costa Health Services, John Pekala, Environ, and Kate Burger, DTSC. On September 10th, they drove all 36 miles of roads where Sierra-Crete was used before deciding on where to sample.
Surface wipe samples were taken on September 11, 12, 21,and 24 in Antioch, Pittsburg, Bay Point, Oakley, and Brentwood where Sierra-Crete was used and at the sensitive receptors - Stoneman Elementary School, O'Hara Park School and the Antioch Youth Sports complex. Both discrete and composite samples were collected. Four background composite samples were also taken. Also, on September 25th and 26th sixteen core samples were taken of the Sierra Crete itself and of soil 3 feet below the base of the roadbase material. Four background core samples were also taken. In addition, they took 2 samples of solid material from two different locations for analysis.
These samples were sent to Alta Analytical labs in Eldorado Hills, CA and tested for dioxins according to EPA Method 1613A. At the request of DTSC, Sierra Crete samples taken from the three sensitive receptor locations were sent to STL in Denver, Colorado to be tested for semivolatile chemicals, metals, hexavalent chromium, and polyaromatic Hydrocarbons.
The two solid surface samples were split so that DTSC could also sample the material at their lab. Two of the Sierra-Crete core samples were split with DTSC as well as one of the subsurface soil samples. They decided not to split the wipe sample extracts because the labs use different methodologies to analyze for dioxin and therefore produce results that aren't comparable. David Berry said that DTSC is comfortable with the work that Alta does and they have used them in the past.
The results are expected back at the end of October.
Dave Berry felt that once the test results were complete it would take about a month to conduct the risk assessment itself.
Devra Lewis from the Regional Water Quality Control Board felt that at the next meeting the group should start to discuss the surface water quality sampling plan. It was decided that a smaller sub-group would meet in the interim to begin developing the surface water sampling plan. Dave Berry would be the contact point for that sub-group.
Dr. Brunner closed the meeting at 10:15.
5. Set next meeting time and Agenda
The next meeting will be Friday November 8, from 9:00 to 11:00 in the Antioch Police Station Community Room at 300 "L" Street in Antioch.