Section 319
NONPOINT SOURCE PPOPRAM SUCCESS STUB
Cleanup of Leaked Petroleum Restores Whetstone Brook
WatPrbndv Imnrnvpd ^'' 'ea'<'n9 ^rom a nearby underground storage tank caused
sheens and degraded biological communities in Whetstone
Brook. This resulted in the state placing the waterbody on its 303(d) list in 1998 for aesthet-
ic and aquatic life support use impairments. Project partners removed the storage tank and
much of the leaked oil from the area. Several years later, biological assessments showed
that Whetstone Brook once again met state water quality standards. Vermont removed the
brook's aesthetic and aquatic life use impairments from its 303(d) list in 2004.
Problem
Whetstone Brook, a 7-mile stream in the
southern Vermont town of Brattleboro, is a
tributary within the state's Lower Connecticut
River Basin. The Vermont Department of
Environmental Conservation (VT DEC) classi-
fies Whetstone Brook as a Class B water—a
designation defined as "suitable for bathing
and recreation, irrigation and agricultural
uses; good fish habitat; good aesthetic value;
acceptable for public water supply with filtra-
tion and disinfection."
In 1990 citizens and VT DEC staff first
observed oil sheens in a 0.2-mile segment near
the mouth of the brook. The following year, VT
DEC located the petroleum source—a leaking
underground storage tank at a nearby gas sta-
tion. Cleanup efforts began immediately.
The leak and residual groundwater contami-
nant plume created an aesthetic nuisance and
impaired aquatic life for several years. VT DEC
monitored macroinvertebrates in Whetstone
Brook using the EPT index—a measure of
pollution-sensitive, aquatic insects inhabiting a
waterbody. Streams showing high EPT rich-
ness are less likely to be polluted than streams
showing low richness in the same geo-
graphic region. In addition, VT DEC evaluated
Whetstone Brook's biotic integrity (Bl), which
measures the presence of pollution-tolerant
VT DEC monitoring staff member taking field notes on Whetstone
Brook. Monitoring is scheduled to resume in 2008.
species. High Bl values characterize streams
with poor water quality and dominated by pol-
lution-tolerant species.
Monitoring results indicated that Whetstone
Brook failed to meet Vermont's Class B water
quality standards for aesthetics and aquatic
life support. As a result, Vermont placed
Whetstone Brook on its 303(d) list of impaired
waters in 1998. VT DEC identified oil/grease as
the primary cause of impairment.
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Project Highlights
Once VT DEC identified the pollution source,
the agency and gas station owner quickly
initiated work to remove the storage tank and
recover much of the leaked oil. By 1996, they
had removed the storage tank and—with the
help of a soil vapor extraction system—up to
4,000 gallons of oil from the surrounding soil
and groundwater.
Even with the cleanup effort, however, residual
petroleum in contaminated groundwater con-
tinued seeping into the brook until late 1999.
VT DEC continued to monitor biological com-
munities, look for oil sheens, and measure oil
seepage along the streambank.
Results
The accompanying table compares key
Whetstone Brook biomonitoring results with
Class B water guidelines. Data highlighted in
bold indicate the waterbody's failure to meet
aquatic life support biocriteria for Vermont Class
B waters. These data led to Whetstone Brook
being added to Vermont's 303(d) list in 1998.
The monitoring team reassessed the seg-
ment in 2002 and found significant biological
improvement. However, before 2004 (when
Vermont revised its listing methodology for
impaired waters), a waterbody could not be
removed from the state's impaired list until
2 years of biological monitoring data showed
compliance with water quality standards. Such
compliance was confirmed in 2003. The EPT
richness, Bl values, and other biological indica-
tors for both years remained well within the
Class B guideline. In addition, the team found
no evidence of oil sheens either year.
Because of these findings, VT DEC concluded
that oil/grease no longer impaired Whetstone
Brook's aesthetic and aquatic life uses. As a
result, Vermont removed the waterbody from
its 303(d) list in 2004. Whetstone Brook is
scheduled to be monitored again in 2008.
Partners and Funding
Remediation costs for this effort totaled
$440,000, with $430,000 coming from
Vermont's Petroleum Cleanup Fund and the
remainder from the service station owner. VT
DEC spent another $68,000 on the groundwa-
ter investigation that tracked the leaking oil to
its source. In addition, approximately $3,000
in section 319 funding supported the participa-
tion of agency monitoring staff.
Whetstone Brook Biomonitoring Results
Sampling site
0.2
0.2
0.2
Date
9/15/1998
9/17/2002
9/11/2003
Assessment rating
Fair
Very good
Very good
Class B Guideline
EPT
17.0
23.0
20.5
> 16.0*
Bl
4.56
2.78
3.33
< 4.50
* In 1998, the Class B Guideline for EPT was 18. Vermont changed the guideline
to 16 in 2002.
I
55
U.S. Environmental Protection Agency
Off ice of Water
Washington, DC
EPA841-F-06-003I
August 2006
For additional information contact:
Eric Perkins
EPA Region 1
617-918-1602
perkins.eric@epa.gov
Steve Fiske
Vermont Department of Environmental
Conservation Biomonitoring Program
802-241-1378
steve.fiske@state.vt.us
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