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

December 27, 1997

John Caffrey, Chairman
State Water Res Control Board
PO Box 100
Sacramento, CA 95812-0100

RE: Implementation of CTR

Dear Chairman Caffrey:

At the State Board hearing on the draft implementation plan for the California Toxics Rule (CTR) a number of presenters discussed aspects of chemicals of concern to them, such as dioxin, copper, etc. With respect to dioxin, there was some concern that monitoring of POTW effluent, which is evidently called for in the draft CTR implementation plan, was not justified based on the projected small contribution of POTWs to the dioxin problem in San Francisco Bay fish. I am contacting the Board on this issue to point out that based on having worked over the past 25 years on PCBs, dioxins and a number of other chemicals of this type, where there is concern about bioaccumulation in fish tissue that could cause the fish to be hazardous to those who use them as food, it is important that the State Board not continue to assume, as some of its staff have done, such as in the BPTCP, that the available forms of a constituent, such as dioxin, PCBs, mercury, etc. are proportional to the total concentration present in water and/or sediments.

For dioxins, it is almost certain that different sources of dioxins, such as POTW discharges, airborne transport from incinerators, stormwater runoff from streets, etc. have significantly different availabilities for uptake by fish and other organisms. Monitoring POTW effluents, urban stormwater runoff, refinery discharges, etc. for dioxins could yield highly misleading information on the control program that is necessary to control the input of dioxins that are bioaccumulating within fish tissue in the Bay. It is important that the implementation plan for the California Toxics Rule make provisions so that a watershed-based, technical stakeholder-driven program can be developed which would generate the data necessary to formulate technically valid, cost-effective control programs. For dioxins, there is need to do work on the availability of each of the major sources to determine if any of them are less/more important than the others as a source that bioaccumulates in fish tissue. With this type of information, it would then be possible to formulate technically valid control programs that focus on those sources that are the primary sources for the excessive bioaccumulation that is occurring in San Francisco Bay fish.

At the Society for Environmental Toxicology and Chemistry (SETAC) national meeting that was held in San Francisco in mid-November, I presented a poster session paper on the Cache Creek mercury problem as it relates to the excessive mercury inputs to the Delta and upper San Francisco Bay. Enclosed is a copy of the poster items that I used in this presentation. I have been working as a volunteer with the Central Valley Regional Water Quality Control Board's Cache Creek Mercury Technical Advisory Committee on helping to formulate an overall program that would address the issue of what part of the mercury that is present in Cache Creek high flows is available to become methylmercury that accumulates in excessive levels in Delta and/or San Francisco Bay fish. As with dioxins, PCBs and other bioaccumulatable chemicals, the total concentration of the constituent, i.e. mercury, in a water is not a reliable basis for cost-effectively regulating mercury. Mercury, like other heavy metals, exists in a variety of chemical forms, only some of which are toxic/available. It is not possible for the chemical analysis of the concentrations and/or loads to reliably predict the extent of mercury bioaccumulation that will occur in a waterbody's fish. The US EPA's regulatory approach for mercury is to assume that worst-case conditions for bioaccumulation prevail in all waterbodies. While this approach is protective, it can also be tremendously wasteful of public resources. With few exceptions, the bioaccumulation of mercury that occurs will be less than that predicted based on US EPA criteria.

This poster summarizes some of the key issues that need to be addressed in regulating mercury inputs from various sources. It also presents information on the regulatory situation that is occurring with mercury associated with the US EPA Region 9's proposed revisions of the California Toxics Rule mercury-based bioaccumulation level. The CTR will temporarily raise the mercury limit from the current 12 ng/L to about 50 ng/L. While some may look on this as a significant relaxation of the standard, in fact, this is a temporary situation where, as discussed in the poster items, it is likely that within a year the US EPA will promulgate a new mercury criterion of about 5 ng/L as part of the Science Advisory Board's review of mercury regulatory issues. POTWs in many parts of the country are having problems meeting the current 12 ng/L ambient water standard that evolved from the "Gold Book" criteria. There will be few that can meet the 5 ng/L standard that will evolve from the current national regulatory efforts underway through the US EPA. This is going to be a significant problem for a number of communities in California and elsewhere.

The Cache Creek mercury situation is like the dioxin, PCB and other bioaccumulatable constituent situations. It is a bioaccumulation problem where the technical field does not understand what forms of mercury present in Cache Creek runoff eventually become bioaccumulatable in Delta or upper San Francisco Bay sediments. The State Board should understand that within a few years, it may find itself in the difficult situation of how to regulate the mercury from the former mining areas when there is massive exceedances of the US EPA criterion based on total recoverable mercury. The mechanical application of the total mercury concentrations as a limit that cannot be exceeded more than once in three years, will cause significant over-regulation and could readily lead to massive expenditures of funds to control non-toxic, non-available forms of mercury.

I fully appreciate that the US EPA's current approach towards regulating bioaccumulatable chemicals is based on a worst-case assumption and Independent Applicability situations where if the exceedance of a numeric criterion/objective occurs more than once in three years, that this sets in motion the water quality limited designation and ultimately TMDLs for the mercury sources. The State Board needs to try to incorporate into the CTR implementation plan an approach that allows the regional boards and others to work together to define the sources of constituents that are contributed to a waterbody where excessive bioaccumulation is occurring that leads to, or significantly contributes to, excessive bioaccumulation. This situation is of importance not only in implementing the NPDES permits, but also in developing the Bay Protection and Toxic Hot Spot clean-up plans.

For your information, enclosed is a review of bioaccumulation issues that I wrote about a year ago after attending a US EPA conference devoted to this topic. Bioaccumulation of hazardous chemicals that results in human health advisories associated with the consumption of fish or other organisms is a real, significant water quality problem in the state that needs to be addressed. However, the mechanical, brute force approach of simply applying US EPA criteria and state standards/objectives based on these criteria is not the way to proceed to use the state's funds wisely to control excessive input of constituents that lead to excessive bioaccumulation.

I suggest that the State Board appoint an advisory panel that could work with the staff in developing technically valid, cost-effective programs for regulating bioaccumulatable chemicals, based on those sources which contribute the chemical to a waterbody in an available form, or that convert to available forms within the waterbody. I would be happy to serve on an advisory panel to assist the State Board and regional boards in developing guidance on how to determine whether a particular constituent that is of concern because of excessive bioaccumulation should be evaluated with respect to its contribution to excessive bioaccumulation. If you have questions on these comments, please contact me.

Sincerely yours,

G. Fred Lee, PhD, DEE

Copy to: WRCB members
W. Pettit

GFL:aa
Enclosure

References as:"Lee, G.F., 'Reregisteration of Diazinon and Chlorpyrifos,' Letter to J. Caffrey, State Water Resources Control Board, Sacramento, December (1997)."