July 7, 1999

Amy Church Haley and Aldrich, Inc. 465 Medford Street Suite 2200& Boston, MA 02129-1400

re:

W. R. Grace & Co. - Conn. 62 Whittemore Avenue Cambridge, MA RTNs 3-00277 & 3-17104 PIP comments

Dear Ms. Church,

This letter is in regard to the documents: Scope of Work, Phase II Comprehensive Site Assessment (SOW) and Report on Evaluation for Asbestos in Soil (Evaluation Report), both produced by Haley and Aldrich, Inc., for W. R. Grace & Co.-Conn. in relation to the asbestos contamination on their Cambridge site. These comments are pursuant to the Public Involvement Plan (PIP) established for this site under the Massachusetts Contingency Plan (MCP; 310 CMR 40) established by the Massachusetts Department of Environmental Protection (DEP).

This correspondence supplements comments in my May 11, 1999 correspondence regarding the above-listed documents, and provides some clarifications to that correspondence.

I believe it is still too early to determine a reasonable "Airborne Asbestos Management and Monitoring Plan" (Containment Plan) without having a better characterization of the site. The only plan that can be discussed at this time is one that is designed, as Chris Lawson from W. R. Grace has been quoted in the Cambridge Chronicle as proposing, "to ensure construction activities pose no risk to human health." [emphasis mine]

Such a plan would ensure that subsurficial asbestos does not become exposed to the environment during construction activities. Covering the area with additional soil and/or providing a temporary enclosing shelter are possible ways to accomplish this goal.

It must be emphasized that if a site evaluation indicates "no imminent hazard" and "no current risk" for the asbestos contamination, then there is no requirement that the soil must be disrupted for any reason other than for remediation of other contaminants. Therefore, an unwarranted increase in risk will result if activities occur that increase the level of asbestos in the air above the ambient concentrations that exist with no such activities.

The currently proposed Containment Plan in the Evaluation Report allows some release of asbestos. Therefore, if the proposed approach is to be undertaken, then at minimum, a full characterization of the site is needed to accurately determine the level of exposure risk that may be present due to an error in the assumptions regarding the site contamination profile. This characterization must include:

1. full characterization of all areas where past testing has found asbestos.
2. more statistically based sampling, using the additional characterization results.

By "full characterization," I am referring to a thorough analysis of the lateral extent of the area surrounding the boring locations which were found to have visible levels of asbestos. This analysis should determine if the boring locations represent areas of diffuse contamination, or if they are indicative of localized areas of high asbestos concentration, such as the edge of a waste site. If these areas are presumed to encompass the types of contamination distributions to be expected on the site, then this analysis would provide an indication of the upper bounds of any concentrated regions of contamination at the site.

However, it should be noted that without further sampling based on the results of the analysis, the probability of encountering more such contaminated regions cannot be determined. But even if the whole site is presumed to be contaminated, this analysis should be performed to indicate whether concentrated regions of contamination may be expected.

Mr. Lawson was also quoted as saying, "This plan includes additional soil sampling in proposed development areas where asbestos has been detected." There is currently no plan to conduct the additional characterization until just prior to disruption of the soil at those locations. As I have mentioned, the characterization must occur as part of the SOW in order that a reasonable Containment Plan may be developed based on data, not speculation.

Note, at this point I am only suggesting that the characterization of the contaminated boring locations which is already planned be carried out during Phase II of the MCP. The current proposal starts disruptive activities at sites where no asbestos was indicated, before the further characterization occurs. It is unknown if concentrated contamination sites exist between the boring locations where no asbestos was indicated. A characterization of the existing "hits" may give an indication of what could be expected between the boring locations.

I can see no reason why this already planned characterization should not occur as part of the SOW, and why it is being detained until after disruptive soil activities commence.

Furthermore, there should be no decrease in the level of containment practices based only on the observation that "monitoring indicates no airborne particulates, low levels of airborne particulates, or low levels of airborne asbestos," which was suggested in the proposed Containment Plan. No decrease should occur unless:

1. there is conclusive evidence that higher concentrations of asbestos do not exist elsewhere on the site at locations that have not been sampled or disrupted.
2. that containment under all possible site conditions can be ensured.

Since the distribution and identification of asbestos on the site are not deterministic, a stochastic model must be assumed, where, like the stock market, "past performance does not guarantee future results." Even if a full site characterization were to be performed, there would be some statistical probability that a region of concentrated contamination may be uncovered during the construction process.

Furthermore, a statement was made at the June 17, 1999, PIP meeting stating that the risk on the site cannot be determined. While this may be true given the currently available information, in fact, a reasonable statement of exposure risk could be made, but only if a truly comprehensive site assessment were to be conducted.

My further comments provide clarifications to my previous (May 11, 1999) correspondence:

1. Directional references (e.g. on page 4: "northeast portion of Zone 4") are in error because the directional marker on Haley and Aldrich's map provided in the Evaluation Report shows east as "north." Therefore, "northeast" is actually southeast, etc.
2. Asbestos has been shown to be mutagenic. See references.
3. No "safe" levels have been determined, particularly for children. Toxicological Profile for Asbestos (Update) dated August 1995, states, "it seems most appropriate at present to continue to assume that these is no threshold for asbestos-induced lung cancer. Furthermore, The Health Effects Institute - Asbestos Research states:

A critical question is whether a "threshold" of biological response can be demonstrated in vitro; that is, are there concentrations of asbestos fibers which do not induce biological endpoints? While many does-response studies have shown no response at one or more low asbestos doses, it is not possible to conclude, on the basis of this evidence alone, that thresholds exists.

4. Adding the results from TEM and other neighborhood testing, 64 of 365 (17.5%) of sampling locations contained visible levels of asbestos, vs. 55 locations indicated in the prior correspondence.

I anticipate your response to my comments.

Sincerely,

Michael Nakagawa

cc:
John Miano, Department of Environmental Protection
Patricia Donahue, Department of Environmental Protection
Sam Lipson, Director of Environmental Health, Cambridge Public Health Department
Harold D. Cox, Chief Public Health Office, Cambridge Public Health Department
Kevin Coghlan, Environmental Health and Engineering
John Wardzell, W. R. Grace & Co.
Cambridge City Hall
Cambridge Main Library
North Cambridge Library
Denise Guerin, Alewife Neighbors, Inc.

References:

Cellular and molecular mechanisms of asbestos carcinogenicity: implications for biopersistence.
Environ Health Perspect. 1994 Oct;102 Suppl 5:19-23

Asbestos fibers are mutagenic after all: new signs of orthodoxy for a paradoxical group of carcinogens.
Ann N Y Acad Sci. 1991 Dec 31;643:271-9