Unreliable Information on the Hazards of Consuming Putah Creek Fish
Due to Excessive Bioaccumulation of Mercury and Lead

Davis South Campus Superfund Oversight Committee
Rt. 2 Box 2879
Davis, CA 95616
530-753-9446
fax 530-753-8220
e-mail [email protected]
http://www.members.aol.com/dscsoc/dscsoc.htm

April 14, 1998

Remedial Project Managers
UCD-DOE LEHR Superfund Site
University of California, Davis
Davis, CA 95616

Dear RPMs,

As a result of the statements made at recent RPM meetings where Brian Oatman and Susan Timm referred to the ATSDR/US EPA initial round of fish sampling data as unreliable, Dr. G. Fred Lee has prepared, on behalf of DSCSOC, the attached comments, "Unreliable Information on the Hazards of Consuming Putah Creek Fish Due to Excessive Bioaccumulaton of Mercury and Lead." Dr. Lee's comments review these issues in order to clarify any misunderstanding of the reliability of the ATSDR-US EPA Region 9 data on the hazards to public health that were detected by bioaccumulation studies that took place in Putah Creek during the summer of 1996.

Dr. Lee invites anyone with questions about his comments to contact him.

Sincerely,

Julie Roth, Ex. Dir;

cc: DSCSOC Ex. Board
PRPs
William H. Taylor
Jane Riggan

G. Fred Lee & Associates
________________________________________
27298 E. El Macero Dr.
El Macero, California 95618-1005
Tel. (530) 753-9630 � Fax (530) 753-9956
e-mail [email protected]
web site: http://members.aol.com/gfredlee/gfl.htm
Please note the new area code for telephone and fax has been changed to 530


Unreliable Information on the Hazards of Consuming Putah Creek Fish
Due to Excessive Bioaccumulation of Mercury and Lead

April 13, 1998

Julie Roth, Exec. Director
DSCSOC
Route 2, Box 2879
Davis, CA 95616

Dear Julie:

Again at the last RPM meeting there was mention that the ATSDR US EPA initial round of sampling fish tissue for hazardous chemicals had problems with the data with respect to indicating that the fish caught off of UCD's campus wastewater treatment plant discharge and the west side LEHR site stormwater runoff were hazardous to eat. Two RPM meetings ago, Brian Oatman made the statement that the data are unreliable. At the last meeting, Susan Timm indicated that she has been told that the ATSDR - US EPA data are unreliable. These kinds of statements require that again on behalf of the public and my obligation to DSCSOC that I review these issues in order to clarify any misunderstanding of the reliability of the ATSDR - US EPA Region 9 data on the hazards to public health that were detected by bioaccumulation studies that took place in Putah Creek fish during the summer of 1996.

I have been involved in mercury bioaccumulation issues in fish for many years. At this time, I am part of a Central Valley Regional Water Quality Control Board mercury TMDL work group that is advising the Central Valley Regional Board and CALFED on how best to proceed to control the excessive bioaccumulation of mercury that occurs in Cache Creek and within the Delta and Upper San Francisco Bay fish that is likely related to Cache Creek mercury input. I am also involved as an advisor to the Central Valley Regional Water Quality Control Board's Sacramento River Watershed Program on the definition of the real water quality problems within the Sacramento River watershed and where such problems are found, working toward addressing these problems in a technically valid, cost-effective manner. The excessive bioaccumulation of mercury in fish within the Sacramento River watershed is one of the primary areas of concern for use impairment of the Sacramento River system. These comments are based on my many years of experience and current activities related to excessive bioaccumulation of hazardous chemicals in fish as they represents a threat to public health and the environment.

Unreliable Information on the Hazards of Consuming Putah Creek Fish

As indicated at both meetings, such statements are inappropriate with respect to indicating that there is any question about the hazards that were associated with consuming fish taken near UCD's campus wastewater treatment plant discharge to Putah Creek. While the reason typically given for unreliability of the data is that a mixed population of fish sizes was used in determining the concentrations to assess whether there was excessive mercury and lead in the fish, as I have pointed out in my writings, the fact that a mixed population of fish, including some small fish, was used means that while the total magnitude of the hazards associated with eating fish taken from this location in Putah Creek is unknown, there is no question about the fact that there is a significant hazard. Additional sampling at that time in which only larger fish were used in developing the average concentration would have raised the magnitude of the hazard to even greater levels since larger fish tend to bioaccumulate mercury and lead to a greater extent than smaller fish.

With reference to the statements made by the US EPA staff at the last RPM meeting that ATSDR is finding that the fish sampled during this past year do not have excessive mercury or lead, it is important to note that there is a major disagreement between the ATSDR and the US EPA on critical levels of mercury in fish. Fish that are no problem with respect to ATSDR mercury levels are significant problems based on US EPA Region 9 critical mercury levels.

It is important to point out that one of the most intensively, if not the most intensively, fished area of Putah Creek in the Davis region is the area immediately adjacent to and downstream of the UCD campus wastewater treatment plant's discharge to the Creek. In the now almost three years that I have been concerned about Putah Creek water quality, virtually every time that I have visited that area of the Creek there have been a number of people fishing in that region.

Other Possible Hazardous Chemicals in Putah Creek Fish

As I pointed out when I first saw the data a year ago, the conclusions by ATSDR that there were no other problems associated with bioaccumulation of other (than mercury and lead) potentially hazardous chemicals in Putah Creek fish is not reliable since the US EPA did not use sufficiently sensitive analytical procedures for some of the other constituents that typically bioaccumulate in fish tissue to hazardous levels. Basically, for the several organochlorine pesticides that I discussed a year ago, the situation is one that ATSDR should not have indicated that there are no other hazardous chemical problems with fish taken from Putah Creek. Dr. William Taylor subsequently agreed with my conclusions on this matter, namely that there could be other hazardous chemical problems which were not detected by the analytical methods used by the US EPA. Hopefully, the analytical methods that are used as part of the second year of sampling of Putah Creek fish conducted by the US EPA Region 9 and ATSDR will be adequate to detect all of the potentially hazardous chemicals that are being found to bioaccumulate to hazardous levels in Putah Creek fish.

One of the groups of chemicals that was not measured in the initial 1996 sampling and I believe has not been measured in the 1997 sampling is dioxins. Dioxins are being found to bioaccumulate in fish to excessive levels in many areas. As I have pointed out previously, any study of bioaccumulation of hazardous chemicals in fish that claims that there are no problems with excessive bioaccumulation when dioxins have not been measured is inadequate and could readily be unreliable. Another reason for bioaccumulation studies to be inadequate is that only a small number of the potentially hazardous chemicals that could bioaccumulate in fish tissue are measured in typical bioaccumulation studies such as those conducted by ATSDR/ US EPA. Those familiar with such studies know that fish taken from some areas contain one or more and sometimes many unidentified peaks representing chemicals that could be hazardous to those who consume the fish. Therefore even if lead and mercury had not been found at excessive concentrations, the fish in Putah Creek could be hazardous for consumption due to inadequate analytical procedure sensitivity used by the US EPA in measuring the concentrations within fish tissue, failure to measure dioxins in the tissue as well as the presence of hazardous chemicals in the tissue that were not identified/reported.

Need for On-going Bioaccumulation Studies

There seems to be a supposition developing among the RPMs and PRPs for the LEHR national Superfund site that if the fish that were sampled during the fall of 1997 do not have excessive levels of mercury, lead or other constituents, there is no need to sample the fish in future years for excessive bioaccumulation. That is not a proper assessment. I have repeatedly pointed out that there can be season-to-season, year-to-year variability in the tissue concentrations of hazardous chemicals in fish associated with runoff from sites like the LEHR site. I have also previously pointed out that bioaccumulation issues for aquatic life in Putah Creek upstream, at and downstream of the LEHR site is an integral part of a credible stormwater runoff monitoring program for the LEHR site. Both UCD and DOE must commit to an on-going program of bioaccumulation monitoring for this site for at least three to five years after the site has been completely remediated and there is no further excavation or other remedial activities at the site and all wastes associated with the site have been removed from the site.

Of particular concern with respect to contaminating stormwater runoff is an area that has yet not been addressed, of plant roots being present in the waste areas which could translocate waste materials through the roots to the leaves and flowers and thereby be a mode of transport of subsurface wastes currently at the site as well as those that might be left at the site upon remediation and thereby be a source of contamination for surface runoff. Even though this problem was pointed out over 2.5 years ago, UCD, DOE and the RPMs have still not taken action to address this issue. This is another of the significant deficiencies in the way in which the LEHR Superfund site is being investigated with respect to protecting public health and environment.

There could readily be seasonal as well as year-to-year variability in the bioaccumulation of excessive concentrations of chemical constituents, especially mercury, in fish at various locations along Putah Creek. As I have pointed out in my previous writings, the excessive bioaccumulation of mercury in the fish near where UCD's campus wastewater discharge occurs to Putah Creek may not be necessarily related to a mercury discharge at that point. It could be caused by creating a more favorable environment for methylmercury formation in the sediments of that region due to the inadequately treated wastewaters discharged to that area. That area at times has sludge deposits associated with the wastewater treatment plant discharges. Such deposits would provide the anaerobic environment which would promote the conversion of bioavailable forms of mercury to methylmercury which tends to bioaccumulate in fish tissue. The presence or absence of sludge deposits is a function not only of the wastewater treatment plant operations, but also of the scour - flow that occurs in Putah Creek. The campus wastewater treatment plant is well documented to be overloaded where it has been providing inadequate treatment to protect the designated beneficial uses of Putah Creek.

The conditions that occurred in 1996 were favorable to formation of methylmercury which lead to the excessive bioaccumulation in the region of the campus wastewater treatment plant discharge. Those same conditions may not have occurred in 1997, but could, however, occur again in 1998 and in subsequent years. It is therefore essential that UCD/DOE continue an on-going mercury and other chemical constituent monitoring program in edible fish taken from various locations along Putah Creek, but especially in the vicinity of the campus wastewater treatment plant discharge in order to address year-to-year variability in the conditions that exist in Putah Creek which impact the methylmercury formation. Additional justification for such studies is based on the fact that Putah Creek at the point of the campus wastewater treatment plant discharge is intensively used by the public as an area for fishing.

Posting of Putah Creek to Warn People of the Hazards of Consuming Fish

Based on my public health background and experience, the ATSDR recommendation that Putah Creek should be posted to warn people about the hazards of consuming fish in the vicinity of the University of California, Davis campus wastewater discharges and stormwater runoff was highly appropriate and prudent public health practice. The fact that the UCD L. Vanderhoef administration has failed to act appropriately on the ATSDR recommendations again reflects the recalcitrant polluter approach that this administration and its staff follow in protecting the public's interests associated with management of campus wastes.

Summary of Issues

In summary, the ATSDR - US EPA Region 9 data released a year ago on Putah Creek fish unequivocally shows that:

The UCD L. Vanderhoef administration has tried to create a smokescreen through UCD propaganda and staff statements that the data collected by the ATSDR and the US EPA are not reliable to indicate that there was a hazard from mercury and lead that had bioaccumulated in fish tissue taken from near the campus wastewater treatment plant discharge. The fact that Susan Timm is now repeating such statements caused me to discuss the facts in this matter again, I believe for the third time, in connection with DSCSOC's discussion of these issues. As I have indicated, if someone questions my assessment of these facts as inappropriate, then I would be happy to have this matter independently peer reviewed by experts in the field. I am confident that such a review would show that my assessment of this situation is correct.

Please contact me if there are questions or comments. Please pass this discussion to the RPMs indicating a willingness to answer questions they may have about it.

Sincerely yours,

G. Fred Lee, PhD, DEE

GFL:oh

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