Health Consultation - Environmental Health Investigations Branch

Health Consultation
EVALUATION OF INITIAL PRIVATE WELL DATA
COLLECTED AT WEST COLLEGE AVENUE AND CLOVER DRIVE
SANTA ROSA, SONOMA COUNTY, CALIFORNIA
MAY 7, 2001
U.S. DEPARTNIENT OF HEALTH AND HUMAN SERVICES
Public Health Service
Agency for Toxic Substances and Disease Registry
Division ofHealth Assessment and Consultation
Atlanta, Georgia 30333

Health Consultation: A Note of Explanation
An ATSDR health consultation is a verbal or written response from A TSDR to a specific request
for information about health risks related to a specific site, a chemical release, or the presence of
hazardous material. In order to prevent or mitigate exposures, a consultation may lead to specific
actions, such as restricting use of or replacing water supplies; intensifying environmental
sampling; restricting site access; or removing the contaminated materiaL
In addition, consultations may recommend additional public health actions, such as conducting
health surveillance activities to evaluate exposure or trends in adverse health outcomes;
conducting biological indicators ofexposure studies to assess exposure; and providing health
education for health care providers and community members. This concludes the health
consultation process for this site, unless additional information is obtained by ATSDR which, in
the Agency's opinion, indicates a need to revise or append the conclusions previously issued.
You May Contact ATSDR TOLL FREE at
1-888-42ATSDR
or
Visit our Home Page at: http://www.atsdr.cdc.gov

HEALTH CONSULTATION
EVALUA TION OF INITIAL PRIVATE WELL DATA
COLLECTED AT WEST COLLEGE AVENUE AND CLOVER DRIVE
SANTA ROSA, SONOMA COUNTY, CALIFORNIA
Prepared by:
California Department of Health Services
Under Cooperative Agreement with the
Agency for Toxic Substances and Disease Registry

Summary
In September 2000, the Environmental Health Investigations Branch (EHIB) of the California
Department of Health Services (CDHS), was asked by the North Coast Regional Water Quality
Control Board (NCRWQCB) to address the potential health impact of private well contamination
from the West College Avenue at Clover Drive PCE (tetrachloroethylene) plume, in Santa Rosa,
California. In January 2001, at the request of community members, CDHS sent a letter to the
Slate Water Resources Control Board (SWRCB) in support of funding for health outreach
activities in the impacted community. The content of the correspondence between the
NCRWQCB, the SWRCB and CDHS is the basis'of this health consultation (Appendix A:
September 2000 and January 2001 Letters). CDHS has a cooperative agreement with the federal
Agency for Toxic Substance and Disease Registry (ATSDR), and this health consultation is being
forwarded to ATSDR for their concurrence.
Background and Statement of Issues
The West College at Clover Drive community is located approximately 50 miles north of San
Francisco, in an unincorporated area in the City of Santa Rosa, within Sonoma County,
California. PCE contamination was detected in wells north of West College Avenue in 1995. The
NCRWQCB began investigating the West College and Clover Avenue PCE plume in December
1999 after learning of contamination in a private well south of West College Avenue. In
December 1999, and January 2000, NCRWQCB staff conducted a well survey in the West
College/Clover Drive area to gain an understanding of private well use. The NCRWQCB
determined that there are approximately 98 parcels served by private wells. This area (south of
West College) falls within the "county island", an unincorporated portion of Santa Rosa, with no
current access to municipal water supplies. In August 2000, after obtaining emergency funds
from the State Water Resources Control Board, NCRWQCB staff began sampling private wells.
At that time, approximately 40 wells had been sampled. Initial sampling results from five wells
revealed concentrations of PCE up to 306 parts per billion (ppb). Subsequent sampling revealed
levels up to 576 ppb. The maximum contaminant level (MCL) allowable in municipal water
supplies is 5 ppb. NCR WQCB staff distributed information in the community about the
contamination, and recommended that an alternative water source (bottled water or treatment
system) be used. In September and October 2000, CDHS staff conducted community outreach
and provided health education about PCE and exposure reduction.
In November 2000, the NCRWQCB began installing well head treatment systems on
contaminated wells in areas where there is no access to a municipal water supply. Residents who
live on West College Avenue were able to be connected to the City of Santa Rosa's municipal
water supply.
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In January 2001, the NCRWQCB received $100,000 from the SWRCB for health outreach
activities in the West College Avenue and Clover Drive community. These activities are being
carried out by Sonoma County Department of Health Services, Environmental Health Division,
with support from CDHS.
Discussion
Evaluation ofHealth Impact:
In September 2000, CDHS staff reviewed private well data provided to us by the NCRWQCB to
determine if the levels of PCE in private drinking water wells pose an immediate health hazard to
residents.
CDHS evaluated non-cancer health effects from exposure to PCE contaminated well water. Noncancer
health effects were evaluated relative to ATSDR health comparison values. We estimated
an exposure dose from ingestion and inhalation for an adult and a child using a private well with
the highest level (306 ppb) of PCE detected at that time (Appendix A: September 2000 Letter).
CDHS assumed that the inhalation dose was equal to the dose received through ingestion. This
assumption is based on a number studies which indicate inhalation exposure to VOC (volatile
organic compound) contaminated water may be as great or greater than exposure from ingestion
alone [1]. Thus, we used the estimated dose calculated for ingestion as a representation of the
inhalation dose. The estimated exposure for a young child (0.04 milligrams per kilograms per day
(mg/kg/day)) approaches acute health standards (Minimal Risk Level (MRL)) for non-cancer
health effects [2]. An acute exposure is considered to be 1-14 days in duration. The acute MRL is
based on a developmental study which showed increased motor behavior (hyperactivity) at an
exposure level of 5 mglkg/day [2]. Additionally, these levels exceed the USEPA MCL of 5ppb,
which is set to be protective over a lifetime of exposure. CDHS concluded that immediate steps
should be taken to eliminate exposures of this magnitude.
Based on our review of the initial data, and the fact that it is likely that exposures occurred for a
number of months if not years, young children are most at risk for non-cancer health effects.
However, since the NCRWQCB has taken measures to eliminate exposures, non-cancer health
effects are not likely to occur.
Health Outreach Activities:
Since September 2000, CDHS staff have conducted health outreach activities in the community,
which have included the following: attended several neighborhood meetings; gone door to door
and provided health and exposure reduction information relating to PCE; presented health
information at a large public meeting held by the NCRWQCB; and provided individual
consultation with community members.
2

Based on the outreach efforts conducted by CDHS, and ongoing community health concerns,
NCRWQCB staff recognized the need for continued health outreach in the community. While
Sonoma County Environmental Health Division is the agency charged with carrying out these
types of activities, limited resources and lack of expertise at the county level was prohibiting the
development and implementation of such a process. In December 2000, the NCRWQCB
requested $100,000 from the SWRCB to fund Sonoma County Department of Health Services in
developing a process for health outreach, while at the same time building capacity within their
agency. CDHS was asked by community members to write a letter to SWRCB supporting the
request for funding (Appendix A: January 2001 Letter).
On January 10,2001, CDHS staff attended the SWRCB hearing and expressed support for the
funding of health outreach activities. Several community members also spoke at the hearing,
urging the board to allocate the funds. The SWRCB awarded $100,000 for health outreach
activities in the community. The award was somewhat unprecedented as the SWRCB deals
primarily with cleanup issues relating to water, not health outreach. CDHS will continue to
provide support to Sonoma County and the NCRWQCB in the development and implementation
of a health outreach plan in the West College Avenue and Clover Drive community.
Children's Health Issues
CDHS and ATSDR recognize that children can be more sensitive to health effects caused by
environmental contaminants, and believe that it is important to search for additional information
that will increase our understanding of the contaminants, and ensure that the children's health is
protected. Thus, our correspondence to the NCRWQCB focused on the exposure a child may
receive.
Conclusion
Based on initial sampling results, CDHS has determined that PCE levels measured in some of the
private wells approached acute MRL's for non-cancer health effects. CDHS recommended that
immediate steps be taken to eliminate exposures from impacted wells. The NCRWQCB
implemented well head treatment systems on impacted wells, and connected residents to
municipal water where available.
Due to the high level of community health concerns, a need for continued health outreach in the
community was identified. Future health outreach activities will be developed and carried out by
Sonoma County Environmental Health, with assistance from CDHS.
Public Health Recommendations and Actions
The Public Health Recommendations and Actions Plan (PHRAP) for this site contain a
description of actions taken. to be taken, or under considerations by ATSDR and CDHS at and
near the site. The purpose of the PHRAP is to ensure that this health consultation not only
3

identifies public health hazards, but also provides a plan of action designed to mitigate and
prevent adverse human health effects resulting from exposures to hazardous substances in the
environment. The CDHS and ATSDR will follow-up on this plan to ensure that actions are
carried out.
Actions Completed
1. September 2000, CDHS responded to the NCRWQCB's request for technical assistance.
2. September-October 2000, CDHS conducted health outreach and education in the
impacted community.
3. January 2001, CDHS responded to community requests to support funding for continued
health outreach by speaking at the SWRCB hearing and writing a letter of support.
Ongoing Actions
1. CDHS will provide technical resources and support to Sonoma County Department of
Health Services, Environmental Health Division, in the development and implementation
of a health outreach plan.
2. CDHS will provide technical assistance to the NCRWQCB, as needed.
3. CDHS will provide individual consultation to residents in the West College A venue and
Clover Drive community.
4. CDHS will continue to keep community members aware of the CDHS and ATSDR
activities in the West College Avenue and Clover Drive community.
Recommendations for Further Actions
L
CDHS/ATSDR recommend that Sonoma County Environmental Health explore avenues
to identify other "county islands" served by private wells, which potentially may be
impacted by industrial sources and provide education relating to sampling and safety of
private well use.
4

Preparers of Report
Environmental and Health Effects Assessors:
Tracy Barreau, R.E.H.S.
Research Specialist
Impact Assessment contractor to the
Environmental Health Investigations Branch
California Department of Health Services
Marilyn C. Underwood, Ph.D.
Staff Toxicologist
Environmental Health Investigations Branch
California Department of Health Services
Tivo Rojas, M.P.H.
Community Health Educator
Environmental Health Investigations Branch
California Department of Health Services
ATSDR Regional Representatives:
William Nelson
Gwen Eng
Regional Representatives, Region IX
Agency for Toxic Substances and Disease Registry
ATSDR Technical Project Officer:
Tammie McRae, M.S.
Environmental Health Scientist
Division of Health Assessment and Consultation
Superfund Site Assessment Branch, State Programs Section
5

Certification
The Evaluation of Private Well Water Data Collected at West College Avenue and Clover Drive
Health Consultation was prepared by the California Department of Health Services under a
cooperative agreement with the Agency for Toxic Substances and Disease Registry (ATSDR). It
is in accordance with approved methodology and procedures existing at the time the public health
consultation was begun.
Tammie McRae, MS
Technical Project Officer, SPS, SSAB, DHAC
The Division of Health Assessment and Consultation, ATSDR, has reviewed this health
consultation and concurs with the findings.
~#
Richard Gilh
Chief, State Program Section, DHAC, ATSDR
6

REFERENCES
1. McKone, Thomas. Human Exposure to Volatile Organic Compounds in Household Tap
Water: The Indoor Inhalation Pathway. Environmental Science Technology
1987;21:1194-1201.
2. Agency for Toxic Substances and Disease Registry. Toxicological Profile for
Tetrachloroethylene. U.S. Department of Health and Human Services; 1997 Sept.
7

APPENDIX A
8

STATE OF CAUFORNIA-HEALTH AND HUMAN SERVICES AGENCY
GRAY DAVIS, Governor
DEPARTMENT OF HEALTH SERVICES
1515 CLAY STREET, SUITE 1700
OAKLAND, CA 94612
(510) 672-4500
f
September 27, 2000
Lee Michlin, Executive Officer
North Coast Regional Quality Control Board
5550 Skylane Boulevard, Suite A
Santa Rosa, CA 95403-2067
Dear Mr. Michlin:
On September 11, 2000 the Environmental Health Investigations Branch (EHIB) of the
California Department of Health Services (CDHS), was asked by the North Coast
Regional Water Quality Control Board (NCRWQCB) to address the potential health
impact of private well contamination from the West College and Clover Avenue PCE
(tetrachloroethylene) plume in Santa Rosa. CDHS conducts health assessment
activities under a cooperative agreement with the federal Agency for Toxic Substances
and Disease Registry (ATSDR).
On September 13, 2000 staff from CDHS, Sonoma County Environmental Health, and
the City of Santa Rosa attended a meeting at the NCRWQCB's office to discuss the
investigation, and magnitude of the problem. The following paragraph summarizes the
history and status of investigation.
PCE contamination was detected in wells north of West College Avenue in 1995. The
NCRWQCB began investigating the West College Avenue and Clover Drive PCE plume
in December 1999 after learning of contamination in a private well south of West .
College Avenue. In December 1999 and January 2000, NCRWQCB staff conducted a
well survey in the West College Avenue and Clover Drive area to gain an understanding
of private well use. The NCRWQCB determined that there are approximately 98
parcels served by private wells. This area (south of West College Avenue) falls within
the "county island", an unincorporated portion of Santa Rosa, with no current access to
municipal water supplies. In August 2000, after obtaining emergency funds from the
State Water Resources Control Board, NCRWQCB staff began sampling private wells.
To date, approximately 40 wells have been sampled. Initial sampling results from 5
wells revealed concentrations of PCE up to 306 ppb (parts per billion). The maximum
contaminant level (MCL) allowable in municipal water supplies is 5 ppb. NCRWQCB
staff distributed information in the community about the contamination, and

Mr. Lee Michlin
September 27, 2000
Page 2
recommended that an alternative water source (bottled water or treatment system) be
used. The NCRWQCB is planning a public meeting in October (date to be announced)
once more data becomes available.
During the meeting CDHS stressed the importance of reducing exposures through
bottled water use. but also emphasized that bottled water would not reduce the
inhalation exposure that a person may receive from volatilization (primarily during
showering/bathing activities). In fact, the inhalation pathway may account for an
exposure dose equivalent to the ingestion dose.
Since the meeting, CDHS staff have estimated an exposure dose for adults and
children using a private well with the highest level (306 ppb) of PCE detected. The
estimated exposure for a young child (0.04 mg/kg/day) approaches acute health
standards (Minimal Risk Level (MRL)) for non-cancer health effects. An acute exposure
is considered to be 1-14 days in duration. The acute MRL is based on a developmental
study which showed increased motor behavior (hyperactivity) at an exposure level of 5
mg/kg/day. Additional studies on inhalation of PCE have shown that the developing
nervous system is at risk because PCE is known to cross the placenta, and is present
in breast milk. It is thought that these developmental effects are irreversible, even if the
exposure ceases. Since it is likely that exposures have been occurring for a number of
months if not 'years, it is critical that immediate steps be taken to eliminate exposures of
this magnitude. CDHS recognizes that steps have been taken by the NCRWQCB to
make the residents aware of the issue, and have recommended that they use
alternative water. However, given the high levels of PCE detected in three of the wells,
it seems prudent that more public health protective measures be implemented to
reduce/eliminate both the ingestion and inhalation pathways.
CDHS also recommends drafting a protocol which evaluates the urgency and course of
action on new well data as it becomes available. Some of these activities may include:
• implementation of well head treatment;
supplying bottled water to impacted and potentially impacted residents;
outreach and education to individual households about exposure; and
• availability of CDHS to provide health consultation.

Mr. Lee Michlin
September 27, 2000
Page 3
, i
, We look forward to discussing these issues with you. If you have any questions please
do not hesitate to call Tracy Barreau at (510) 622-4489 or Marilyn Underwood, Ph.D. at
(510) 622-4415 .
.~~
~~~---
Tracy Barreau, R.E.H.S.
Research Specialist
Environmental Health Investigations Branch
Marilyn Underwood, Ph.D.
Staff Toxicologist
Environmental Health Investigations Branch
cc:
Jo Bentz
North C.Oast Regional Water Quality Control Board
5550 Skylane Boulevard, Suite A
Santa Rosa, CA 95403
Susan Warner
North Coast Regional Water Quality Control Board
5550 Skylane Boulevard, Suite A
Santa Rosa, CA 95403
Lauren Brown, P.E.
City of Santa Rosa
Utilities Department, Engineering Division
69 Stony Circle
Santa Rosa, CA 95401
Jonathan Krug, M.P.H., R.E.H.S.
County of Sonoma Environmental Health
1030 Center Drive, Suite A
Santa Rosa, CA 95403-2067

SrAlE of: CAUFORNIA-HEALTHAND HUMAN SEfMCESAGENCY
DEPARTMENT OF BEALm SERVICES
DIVISION OF ENVIRONMENTAL AND OCCUPATIONAL
DISEASE CONTROL
1515 CLAY STREET, SUITE 1701
OAKLAND. CA 94612
(510) 622-4900
GRAY DAVIS, Gcm/mcH'
January 8,2001
Mr. Ed Anton
Acting Executive Director
Executive Office
State Water Resources Control Board
1001 I Street, 25 th Floor
Sacramento, CA 95814
Dear Mr. Anton:
The California Department of Health Services (CDHS) was contacted by the North
Coast Regional Water Quality Control Board (NCRWQCB) in September 2000
concerning the West College at Clover Avenue tetrachloroethylene (PCE) plume
investigation. NCRWQCB staff requested assistance in addressing health concerns
relating to residential exposure to PCE contamination in private wells. It is our
understanding that the NCRWQCB has requested funding to address community health
concerns through the clean-up and abatement fund. This item will be discussed at the
State Water Resources Control Board meeting on January 10, 2001. CDHS would like
to express its support for the funding of this item.
CDHS staff reviewed the initial well sampling data and have determined that PCE levels
in a few ofthe wells (>300 ppb [parts per billion]) exceed acute (exposure duration 1-14
days) health standards for non-cancer health effects. A number of the wells (>100 ppb)
exceed chronic (exposure duration >365 days) health standards for cancer health
effects. It appears that these exposures may have been ongoing for a number of years.
While the NCRWQCB has taken steps to eliminate these exposures, there are a great
deal of health concerns being voiced by residents. Our experience with communities
around hazardous waste sites has been such that a process of health education and
community participation is a critical first step in addressing community health concerns.
CDHS staff met with Dr. Mary Maddux-Gonzalez, Health Officer with the Sonoma
County Department of Health Services as well as staff from the NCRWQCB to discuss
options for addressing health concerns in the community impacted by the PCE
contamination. Dr. Maddux-Gonzalez has expressed a desire to develop a process for

Mr. Ed Anton
January 8, 2001
Page 2
outreach and education in this community if funding were available. CDHS would
support these efforts and assist Sonoma County in this process as we believe this to be
necessary for the community.
Sincerely,
~------;>
Raymond Richard Neutra, M.D., Dr.P.H., Chief
Division of Environmental and Occupational Disease Control
cc:
Mary Maddux-Gonzalez, M.D., M.P.H
Health Officer
Sonoma County Department of Health Services
625 5 th Street
Santa Rosa, CA 95404
Susan Warner
North Coast Regional Water Quality Control Board
5550 Skylane Boulevard, Suite A
Santa Rosa, CA 95403
Sharon Marchetti
Sf. Josephs Memorial Hospital
789 Lombardi Court, Suite 205
Santa Rosa, CA 95407
Marilyn C. Underwood, Ph.D.
California Department of Health Services
1515 Clay Street, Suite 1700
Oakland, CA 94612