PUBLIC HEALTH ASSESSMENT

HOCOMONCO POND
WESTBOROUGH, WORCESTER COUNTY, MASSACHUSETTS

APPENDICIES

Appendix 1. Figures

Appendix 2. Tables

Appendix 3. Summary of Written Correspondence Received during the Public Comment Period

Appendix 4. Responsiveness Summary

APPENDIX 1 – FIGURES

Figure 1.

APPENDIX 2 – TABLES

Table 1
On-Site Soil Contamination

Contaminant	Levels (in ppm)	Comparison Values (in ppm)	Source	Location	Depth (in feet BLS)	Year Detected
Total Carcinogenic PAHs	682.4	.12	CREG	At abandoned
Napthalene	ND	NA		tank farm	0-.5	1988
Benzo(a)Pyrene	84	.12	CREG	south of
Arsenic	5.3	15	RfD*C	Hocomonco Pond
Total Carcinogenic PAHs	203.7	.12	CREG	Between Kettle	0-2	1984
Napthalene	29.4	NA		Pond and Otis St.
Total Carcinogenic PAHs	22.0	.12	CREG	Southwestern	.5-1	1984
Napthalene	110.0	NA		Edge of Hocomonco Pond
Total Carcinogenic PAHs	2,510.7	.12	CREG	At abandoned
Napthalene	4,470	NA		tank farm	2.0-2.5	1988
Benzo(a)Pyrene	311	.12	CREG	south of Hocomonco Pond
Total Carcinogenic PAHs	690	.12	CREG	At former	3	1984
Napthalene	3,090	NA		lagoon
Total Carcinogenic PAHs	95.6	.12	CREG	Immediately	10-12.5	1989
Napthalene	1,110	NA		east
Benzo(a)Pyrene	14	.12	CREG	of Kettle Pond
Total Carcinogenic PAHs	102.6	.12	CREG	Immediately	12-12.5	1989
Napthalene	130	NA		west
Benzo(a)Pyrene	15	.12	CREG	of Kettle Pond

Table 2
On-Site Sediment Contamination

Contaminant	Levels (in ppm)	Comparison Values (in ppm)	Source	Location	Date Detected
Total Carcinogenic PAHs	1,500	.12	CREG	Kettle Pond
Napthalene	28,000	NA		Surface Sediment	1984
Arsenic	111	15	RfD*C
Total Carcinogenic PAHs	170	.12	CREG	Kettle Pond
Napthalene	620	NA		Surface Sediment	1988
Arsenic	4.2	15	RfD*C
Total Carcinogenic PAHs	119.7	.12	CREG	Hocomonco Pond	1990
Benzo(a)pyrene	20.1	.12	CREG	50 feet west of
Napthalene	1.0	NA		drainage pipe
Arsenic	37.0	15	RfD*C	discharge point
Total Carcinogenic PAHs	30.3	.12	CREG	Hocomonco Pond	1990
Benzo(a)pyrene	4.3	.12	CREG	at drainage pipe
Napthalene	4.5	NA		discharge point
Arsenic	27.0	15	RfD*C
Total Carcinogenic PAHs	12.5	.12	CREG	Hocomonco Pond	1990
Benzo(a)pyrene	1.0	.12	CREG	southeastern edge
Napthalene	609	NA		north of Kettle Pond
Arsenic	234	15	RfD*C
Total Carcinogenic PAHs	54.2	.12	CREG	Hocomonco Pond	1990
Benzo(a)pyrene	7.2	.12	CREG	at discharge point
Napthalene	124	NA		to Otis St. culvert
Arsenic	21	15	RfD*C

Table 3
Storm Drain Sediment Contamination

Contaminant	Levels (in ppm)	Comparison Values (in ppm)	Source	Location	Year Detected
Total Carcinogenic PAHs	33.4	.12	CREG	In storm drain
Napthalene	40.6	NA		leading to	1984
Benzo(a)pyrene	9.4	.12	CREG	Hocomonco Pond

Table 4
On-site Ground Water Contamination

Contaminant	Levels (in ppb)	Comparison Values (in ppb)	Source	Location	Date Detected
Napthalene	11,000	20	LTHA	Shallow Overburden
Benzene	90	1.2	CREG	at northern edge of Kettle Pond	1984
Napthalene	11,000	20	LTHA	Deep Overburden
Benzene	91	1.2	CREG	at northern edge of Kettle Pond	1984
Napthalene	8,600	20	LTHA	Shallow Overburden
Benzene	63	1.2	CREG	at northern edge	1989
Arsenic	34	3	RfD*C	of Kettle Pond
Napthalene	13,000	20	LTHA	Deep Overburden
Benzene	110	5	CREG	at northern edge	1989
Arsenic	25.1	3	RfD*C	of Kettle Pond

Table 5

On-site Surface Water Contamination

Contaminant	Levels (in ppb)	Comparison Values (in ppb)	Source	Location	Date Detected
Napthalene	25	20	LTHA	Hocomonco Pond at
Benzene	27	1.2	CREG	terminus of storm drain	1984
Carcinogenic PAHs	4.5	0.006	CREG	Hocomonco Pond at	1990
Arsenic	14.1	15	RfD*C	terminus of storm drain
Napthalene	530	20	LTHA	Storm Drain leading to
Carcinogenic PAHs	35	0.006	CREG	Hocomonco Pond	1984

Table 6
Food Chain Contamination

Contaminant	Levels (in ppb)	Spieces	Sample Preparation	Location	Date Detected
Carcinogenic PAHs Napthalene	2.72 31.7	Perch	5 fillet composite	Hocomonco Pond	1990
Carcinogenic PAHs Napthalene	1.83 42.8	Pumpkinseed	5 fillet composite	Hocomonco Pond	1990
Carcinogenic PAHs	5.25	Catfish	4 fillet composite	Hocomonco Pond	1990
Standards are not available for these contaminants in fish ppb-parts per billion

Table 7

Off-site Sediment Contamination

Contaminant	Levels (in ppm)	Comparison Values (in ppm)	Source	Location (in feet East of Otis St. Culvert)	Depth (in feet BLS)
Total Carcinogenic PAHs	62.3	.12	CREG	69	0-2
Benzo(a)pyrene	6.3	.12	CREG
Napthalene	92	NA
Arsenic	5.6	15	RfD*C
Total Carcinogenic PAHs	956	.12	CREG	165	0-2
Benzo(a)pyrene	44.1	.12	CREG
Napthalene	36	NA
Arsenic	5.8	15	RfD*C
Total Carcinogenic PAHs	14.7	.12	CREG	800	0-2
Benzo(a)pyrene	.99	.12	CREG
Napthalene	.83	NA
Arsenic	8.1	15	RfD*C
Total Carcinogenic PAHs	50.6	.12	CREG	69	2-4
Benzo(a)pyrene	5.2	.12	CREG
Napthalene	130	NA
Arsenic	6.6	15	RfD*C
Total Carcinogenic PAHs	137.3	.12	CREG	265	2-4
Benzo(a)pyrene	14.2	.12	CREG
Napthalene	180	NA
Arsenic	4.2	15	RfD*C
Total Carcinogenic PAHs	29.2	.12	CREG	365	2-4
Benzo(a)pyrene	2.8	.12	CREG
Napthalene	25.3	NA
Arsenic	4.2	15	RfD*C

Table 8

Off-site Surface Soil Contamination

Contaminant	Levels (in ppm)	Comparison Values	Source	Location	Date Detected
Total Carcinogenic PAHs	7.1	.12	CREG	Immediately South of Smith Valve Pky Storm Drain	1984
Total Carcinogenic PAHs	32.1	.12	CREG	Immediately South	1988
Benzo(a)pyrene	3.4	.12	CREG	of Smith Valve Pky
Napthalene	.52	NA		Storm Drain
Arsenic	18.8	15	RfD*C

Table 9
Toxic Release Inventory (TRI) Data for Westborough
Amounts released to air (in pounds) for 1990.
Compound	Amount Released
Acetone	9,140
1,1,1-Trichloroethane	10,917
Phenol	4,655
Formaldehyde	750
Creosote	750
Lead	250

Table 10

Completed Exposure Pathways

Pathway Name	Source	Environmental Media	Point of Exposure	Route of Exposure	Exposed Population	Time
Sediment	On-site Lagoons	Pond Sediment	Hocomonco Pond	Dermal contact ? Ingestion	Individuals frequenting site	Past Present
Surface Water	On-site Lagoons	Surface Water	Hocomonco Pond	Dermal contact ? Ingestion	Individuals frequenting site	Past Present
Biota	Surface water	Biota	Hocomonco Pond & Discharge Stream	Ingestion	Individuals fishing in pond waters	Past Present
Sediment	Hocomonco Pond	Discharge stream sediment Discharge stream	Dermal contact ? Ingestion	Individuals fishing in stream waters	Past Present

Table 11

Potential Exposure Pathways

Pathway Name	Source	Environmental Media	Point of Exposure	Route of Exposure	Exposed Population	Time
Soil	Tank farms	Soil Sediment	Tank farms	Dermal contact ? Ingestion	Individuals frequenting site	Past Present
Ground Water	Kettle Pond	Ground Water		Ingestion		Future

Table 12

Cancer Incidence in
Westborough, MA
1982-1988

Type of Cancer	Sex	Expected	Observed	SIR
Melanoma	Male Female Total	4.6 4.2 8.8	5 3 8	108 NC 91
Stomach	Male Female Total	4.8 3.2 8.0	3 5 8	NC 157 100

SIR-Standardized Incidence Ratios
NC-Rates are not calculated when less than five cases are observed.

APPENDIX 3 – SUMMARY OF WRITTEN CORRESPONDENCE RECEIVED DURING THE PUBLIC COMMENT PERIOD

Hocomonco Pond site
Public Comment

Name and Address	Information Supplied      Request	Comment
Razelle S. Hoffman, Risk Assessment Specialist ENSR Consulting and Engineering 35 Nagog Park, Acton, MA 01720		X

APPENDIX 4 – RESPONSIVENESS SUMMARY

SUMMARY OF PUBLIC COMMENTS

This responsiveness summary addresses comments that were received by MDPH or ATSDR during the public comment period for the Hocomonco Pond NPL site. This period was from August 12, 1993 to September 11, 1993. The MDPH received written commentary from ENSR, an environmental consulting firm representing Beazer Inc., who currently owns the firm that conducted wood treatment operations at the pond between 1928 and 1942. It should be noted that Beazer was not associated with the firm during that time. ENSRs commentary is addressed in the following section.

ENSR GENERAL COMMENT 1: ENSR believes that the use of the word "contaminants" could be misconstrued as being associated with a public health threat and suggests the use of the word "compound" in its place.

Response: MDPH believes the word contaminant is not alarming or indicative of a health threat and that its use in the document is appropriate.

ENSR GENERAL COMMENT 2: ENSR believes the public comment draft of the document to be more alarming in nature than the earlier release reviewed by the state and federal environmental agencies.

Response: MDPH disagrees with the above assertion and believes that every effort was made to convey that the site does not pose a health risk to individuals who stay away from areas where elevated contamination levels were detected. MDPH also believes that these areas are clearly identified in the document.

ENSR GENERAL COMMENT 3: ENSR believes that the compounds at the site need to be differentiated by those whose existence is due to activities by Koppers Inc.-related interests and those that are not. (Note: Koppers Inc. owned the wood treatment firm when it was listed on the NPL in 1983 and not when it conducted wood treatment operations at the pond between 1928 and 1942.)

Response: MDPH believes that the source of contaminants does not need to be distinguished since the purpose of this document is to determine health risks associated with the site and not liability.

ENSR SPECIFIC COMMENT 1: This comment refers to language on page 14 of the second paragraph stating that given the possibility of future developments in PAH toxicology, the levels of PAH exposure considered safe may change. ENSR believes that the word "safe" should be substituted with the phrase "no significant increase in health risk".

Response: MDPH agrees that no PAH exposure is entirely risk free and has modified the statement accordingly.

ENSR SPECIFIC COMMENT 2: ENSR believes that the concerns and associated recommendations regarding inhalation of PAHs by nearby residents in the event of a forest fire at the site are ill-founded. ENSR maintains that the release of PAHs as a result of the burning of trees would far outweigh PAH contamination volatilized by the fire. In addition, ENSR considers the point to be insignificant since the contaminated media will be removed and placed in a capped and lined landfill.

Response: The ATSDR Public Health Assessment identifies all past, present and future health risks associated with exposure to site-related contaminants. The present risk must therefore be predicated on current site conditions and not those that may or may not exist in the future. MDPH agrees that PAHs will be released as a result of burning trees but we believe that the volatilization of PAH contamination prior to clean-up at the site in the event of a forest fire also needs to be considered. It should also be noted that it is stated in the document that it is not certain what, if any, health risks would exist in the event of such exposure.

ENSR SPECIFIC COMMENT 3: ENSR believes the plan for environmental health education among the medical community practicing in areas near the site is unnecessarily alarming.

Response: MDPH disagrees with this assertion and we believe it to be important that health professionals in the area know when a site does not pose a health concern as well as when it may.

ENSR SPECIFIC COMMENT 4: ENSR believes that the document should be consistent in the use of either the term environmental pathway or exposure pathway.

Response: The term exposure pathway is the correct term and if appropriate the document will be revised accordingly.

ENSR SPECIFIC COMMENT 5: ENSR believes that the second sentence of the introductory paragraph of the environmental pathways section should be replaced with "To estimate if individuals engaged in activities on or near the site have a significant risk increase in the probability of developing adverse health effects, environmental, chemical and human components that could potentially lead to human exposure must be evaluated".

Response: The introductory paragraph used in the pathways section is standard language used in all ATSDR Public Health Assessments. The suggested replacement also incorporates wording pertaining to health risk which is not addressed in the pathways section.

ENSR SPECIFIC COMMENT 6: ENSR believes that the statement on page 9 that PAHs are of low water solubility and strongly adhere to sediments in soils is inaccurate. In addition, ENSR believes that the statement on page 12 that all PAHs of high molecular weight are carcinogenic is not true.

Response: The intent of the last sentence in the third paragraph on page 9 was to convey that PAHs as a whole are not environmentally mobile in aquatic media. MDPH believes this to be accurate in that even the low weight PAHs which are more water soluble than those of high weight are not as water soluble as constituents of other classes of environmental contaminants. With respect to the commentary on the second paragraph, it is never stated that all PAHs of high molecular weight are carcinogenic. It is stated that those large PAHs that are suspected to be carcinogenic have low water solubilities. The parenthetical expression defines large, ie. those of high molecular weight.

ENSR SPECIFIC COMMENT 7: ENSR believes that assuming that all PAHs are as carcinogenic as Benzo(a)pyrene [B(a)P] can lead to a one hundredfold overestimation of cancer risk and that newer assessment methodologies have been proposed to more accurately estimate risk associated with exposure to PAH mixtures.

Response: It should be noted that the cancer risk slope for B(a)P was not applied to the entire mixture of PAHs found in environmental media at the site but of those believed to have carcinogenic activity that are listed in the document. ATSDR assumes these compounds to be as carcinogenic as B(a)P when deriving their comparison values and risk estimates.

ENSR SPECIFIC COMMENT 8: ENSR believes the first sentence of the first paragraph on page 12 stating that human exposure to surface water contaminants is occurring via dermal contact should be replaced with "may occur via dermal contact".

Response: Considering that human activity was observed in pond waters, it can be safely stated that exposure via dermal contact is occurring. The extent of this exposure is considered in other sections of the document.

ENSR SPECIFIC COMMENT 9: ENSR believes the word "therefore" in the second sentence of the first paragraph on page 12 should be eliminated.

Response: MDPH believes the original wording is correct.

ENSR SPECIFIC COMMENT 10: ENSR requests clarification regarding the depth of dredging at Kettle Pond.

Response: The public comment release is correct stating the dredging at Kettle Pond will be to a depth of five feet. This is per the Explanation of Significant Differences presented on May 11, 1993. The initial release ("red cover"), which is for review by government environmental agencies, is no longer current with respect to the remedial plan.

ENSR SPECIFIC COMMENTS 11 and 12: ENSR believes that the cancer slope factor was developed based on the findings of one animal study and may not be valid for use in quantitative risk assessment. As a result, they do not believe that the mention of these studies in statements on page 14 is justified.

Response: In order to be protective of public health, valid animal studies demonstrating an effect of exposure with an increased risk of cancer development must be considered and the results incorporated into the Public Health Assessment. Since an increase in stomach cancer was noted among animals administered PAHs and since the cancer slope factor has not been changed by USEPA, these statements will be retained in the document.

ENSR SPECIFIC COMMENTS 13 and 14: ENSR believes that the mention of the completed biota exposure pathway is indicative of an elevated health risk resulting from such exposure. ENSR does not believe that ingestion of contaminated fish poses a health risk and that the third conclusion, first and second recommendations, and first Public Health Action Plan should be modified accordingly.

Response: Description of a completed exposure pathway in the pathways analyses section does not mean that a public health threat exists. The extent of health risk associates with this exposure is discussed in the Public Health Implications section of the document. The MDPH does believe ingestion of fish from Hocomonco Pond to pose a health risk in those individuals regularly (more than once per month) incurring such exposure; especially those consuming catfish where levels as high as 5.25 parts per billion (ppb) (page 3-54, Public Health and Environmental Assessment for Hocomonco Pond and Discharge Stream, Keystone Environmental Resources Inc., 1992) were detected. The language in these section of the document will therefore be retained and MDPH believes that the fishing ban at Hocomonco Pond should remain in effect until further fish monitoring data indicate that such a ban is no longer necessary.

ENSR SPECIFIC COMMENT 15: ENSR questions the practice of eliminating monitoring results whose value is None Detected (ND) from consideration of the mean contaminant value when conducting quantitative risk assessment. In addition ENSR questions the value of 5.25 presented for the PAH level in catfish. Finally ENSR notes that PAH levels detected in fish sampled from Hocomonco Pond were similar to those detected in Jordon Pond approximately five miles west of the site.

Response: The fish contamination values presented in Table 6 of the Public Health Assessment are maximum values detected. In some instances the fish sample was monitored in duplicate. In those instances where the maximum value was a duplicate the mean of the two values was presented. "None Detected" was never removed from consideration when presenting the maximal values. Please see previous response for the location of the maximum value for PAH contamination in catfish. MDPH also believes that mention of the similarity in PAH levels detected in fish sampled from Hocomonco and Jordon Ponds is misleading. Jordon Pond receives runoff from a highly travelled sector of Route 9. It is expected that Jordon Pond also has high PAH levels and therefore PAH levels in fish sampled here would also have elevated PAH levels.

ENSR SPECIFIC COMMENT 16: ENSR believes that the first sentence of the first paragraph on page 10 stating further exposure to PAHs in sediment will be reduced upon completion of remedial plan implies that the target clean-up levels are not adequately protective of human health.

Response: No implication whatsoever is meant regarding the future completion or removal of a completed pathway described in the pathways analyses section. Human health risk for a potential or incomplete pathway if addressed is done so in the Public Health Implications section of the document.

ENSR SPECIFIC COMMENT 17 and 18: ENSR disagrees with the conclusions that ingestion of fish caught from Hocomonco Pond and dermal contact with sediment pose a potential health risk to individuals engaged in these activities at the pond.

Response: MDPH maintains that based on regular exposure to PAHs via these two pathways and using the cancer slope factor currently accepted by both USEPA and ATSDR, exposure to PAHs via these two pathways poses an elevated cancer risk. It should be noted that the document very clearly states that individuals who do not access the site are at no elevated health risk resulting from exposure to site-related contaminants.

ENSR SPECIFIC COMMENT 19: ENSR believes that the description of the completed surface water pathway is indicative that a health risk exists as a result of the existence of this pathway.

Response: The pathways section does not address risk. It is clearly stated in the introductory paragraph of the section, "The presence of a complete exposure pathway, does not, however, mean that adverse health effects will occur or have occurred in the past as a result of such exposure".

ENSR SPECIFIC COMMENTS 20-23: ENSR believes that the use of the word contaminant is inappropriate.

Response: Please see response to General Comment number one.

ENSR SPECIFIC COMMENT 24: ENSR believes that the second sentence of the third full paragraph on page 15 describing the effects of benzene exposure should state that individuals incurring such exposure would be at increased risk of leukemia development (not "at risk of leukemia development").

Response: MDPH agrees and will modify as appropriate.

ENSR SPECIFIC COMMENT 25: ENSR believes that the statement regarding health risks associated with the site should read: "Insufficient data exists at present to estimate if individuals involved in activities on and around the site (ie. swimming and fishing) are at increased risk of developing adverse health effects.

Response: MDPH disagrees with this statement. It is unlikely that individuals involved in activities away from the site are at increased risk of adverse health effects associated with exposure to site-related contaminants. The extent of the public health concern posed by the site is uncertain since it is not exactly known to what extent activities on the site are ongoing. It is certain that some exposure resulting from on-site activities is occurring since such activities have been noted by federal environmental and state health officials.

ENSR SPECIFIC COMMENT 26: ENSR believes that continued monitoring of cancer rates in Westborough is unnecessary and the recommendation is alarming in nature since they believe that any observed increase in cancer incidence in Westborough could be attributable to a multitude of factors unrelated to the site.

Response: While MDPH recognizes that all cancer elevations within an area are not solely due to environmental exposure, we also believe that continued monitoring of cancer rates in Westborough through the Massachusetts Cancer Registry is necessary as it is with any area where a potential environmental health threat exists. If an elevation of a cancer specific to a certain anatomical site is observed in an area in proximity to where a release of environmental contaminants is known to have occurred, the plausibility that exposure to these contaminants could result in the observed increase would need to further explored. This would include determining the prevalence of other risk factors associated with the cancer in question in the area of concern.

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