ENVIRONMENTAL
STATUS REPORT
for the
U.S. VIRGIN ISLANDS
0
Q
ST. THOMAS
' A^«
May 1983
ST. JOHN
ST. CROIX
&EPA
UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
REGION II
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VIRGIN ISLANDS
ENVIRONMENTAL STATUS REPORT
MAY 1983
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TABLE OF CONTENTS
SECTION PAGE
LIST OF FIGURES AND TABLE iii
AIR QUALITY
Progress in Control of Conventional Air Pollutants 1
Status of Air Quality 1
Priority Air Quality Problem 3
0 Total Suspended Particulates and Sulfur Dioxide
on St. Croix
SURFACE WATER QUALITY
Progress in Water Quality 4
Status of Water Quality 5
SURFACE DRINKING WATER AND GROUND WATER
Status of Public Water Supply Systems 9
Groundwater Sources of Drinking Water 13
Priority Drinking Water Problems 15
0 Insufficient Quantity
0 Persistent Violations in Public Water Supply Systems
HAZARDOUS WASTES 16
PESTICIDES 16
RADIATION 17
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LIST OF FIGURES AND TABLE
Figure
1
2
3
4
5
6
United States Virgin Islands
Public Water Systems
Size Distribution of CWS's
Community PWS's with Bacti Violations
Community PWS's with Turbidity Violations
Percentage of Community PWS's
in Violation for Bacti
Percentage of Community PWS's
in Violation for Turbidity
Page
2
9
10
10
11
12
12
Table
Paqe
Summary of Source Control Problems
by Segments
111
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AIR QUALITY
PROGRESS IN CONTROL OF CONVENTIONAL AIR POLLUTANTS
The extensive data necessary to establish long-terra air quality
trends do not exist for the Virgin Islands. Its low population
density and lack of major pollution sources (except along the
southern coast of St. Croix), have helped the Virgin Islands
avoid air quality problems.
STATUS OF AIR QUALITY
The Virgin islands attains the ambient air quality standards for
CO, 03 and NO2« The industrial southern part of St. Croix is
currently designated as "unclassifiable" with respect to attainment
of the TSP and S02 air quality standards.
Discussion of Air Quality for Each Air Quality Control Region
Although the approximately fifty islands comprising the Territory
of the Virgin Islands are classified as one air quality control
region, the three major islands may be addressed separately
concerning air quality attainment status (see Figure 1).
St. Croix - Unlike the rest of the Virgin Islands, St. Croix
supports a large industrial complex. Dispersion modeling analyses
indicates that ambient concentrations of TSP and S02 could approach
the air quality standards for these pollutants. As a result,
the southern portion of St. Croix is designated "unclassifiable"
with respect to TSP and S02« Also, the S02 concentrations in
this area are near the limits set by the Prevention of Significant
Deterioration rgulations.
The major point sources of TSP and S02 on St. Croix include:
Amerada Hess, Martin Marietta Alumina and St. Croix Petrochemical.
Although these facilities are the major emitters of TSP and S02i
they are efficiently controlled and comply with all 'applicable
air quality regulations. However, accidents have occurred that
have threatened to cause violations of the air quality standards.
In addition to point sources, fugitive emissions from industrial
storage piles and open burning at the municipal dump contribute
to TSP levels.
St. Thomas - While St. Thomas is in attainment of all ambient air
quality standards, the island could experience occasional, isolated
air pollution problems due to the major S02 and TSP source in
the Virgin Islands, the Water and Power Authority. In addition,
the expansion of Truman Airport and occasional open burning at
the municipal dump can cause local TSP air quality problems.
St.
in
John - The only potential source of significant air pollution
St. John is open burning at the municipal dump.
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FIGURE 1
51. THOMAS
ST. CIOIX
4IIAMMC UCIAM
VH«IM KLAMOi
UNITID STATES
VIRGIN ISLANDS
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PRIORITY AIR QUALITY PROBLEM
0 TSP and S02 on St. Croix
There are no significant air quality problems currently degrading
the air quality of the Virgin Islands.
However, as stated above, the ambient levels of TSP and S02 on
St. Croix could approach the air quality standards. The potential
SC>2 problem stems from new and expanded industries located in
the island's South Shore Industrial Complex. These additional
SC>2 emissions are resulting in ambient SC>2 concentrations close
to the area's increment limit under the Prevention of Significant
Deterioration program.
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SURFACE WATER DUALITY
PROGRESS IN WATER QUALITY
The Virgin Islands are located approximately 1400 nautical
miles southeast of New York and about 900 nautical miles
southeast of Miami, Florida. They are made up of three
major islands, St. Thomas, St. John, and St. Croix, and
approximately fifty smaller uninhabited islands and cays.
The Virgin Islands have been broken down into the following
three segments for the purpose of discussion of water quality
issues (See Figure 1):
0 St. Thomas (52.8 miles of shoreline)
0 St. John (49.7 miles of shoreline)
° St. Croix (70.3 miles of shoreline)
The Department of Conservation and Cultural Affairs (DCCA)
has conducted a monitoring program for all bays in the Virgin
Island:; since 1973. Data on coliforms, dissolved oxygen (DO),
salinity, temperature and turbidity have been collected monthly
since t:hat time.
The Virg in Islands have many open bays which are flushed by
high energy wave action, currents, and tides which prevent
the build up of nutrients from discharges from sewage treatment
plants, erosion, and boat discharges. The quality of the
water in these open bays is pristine.
i i
!i
Water quality data indicate that all these open'bays have main-
tained their natural water quality conditions. Water quality
conditions in all the following bays reflects relatively
pristire quality: all waterways in St. John except Coral Bay
(which is being adversely affected by sediment runoff) and
Cruz Bey (which exhibits sporadic standards contraventions)
and all the bays in St. Thomas except for the Mangrove Lagoon
and Charlotte Amalie Harbor.
Data fcr all of the St. John coastal waterways indicate that
water quality conditions have remained excellent and show no
signs of deterioration over the last five years of record.
In Christiansted Harbor on St. Croix, water quality has steadily
improved over the last several years since the St. Croix primary
publicly owned treatment works (POTW) became operational„
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Water quality along the south shore of St. Croix which had
been adversely affected by industrial discharges and dredging
activities of Amerada.Hess has also significantly improved.
Water quality parameters except for turbidity now approach
conditions which reflect relatively pristine water quality.
Benthic communities and some previously impacted reef struc-
tures have also recovered to a limited extent.
STATUS OF WATER QUALITY
Existing overall water quality conditions in the U.S. Virgin
Islands are excellent. Whatever instream problems that do
exist are of a local nature affecting only specific harbors
or certain shoreline stretches. Table 1 summarizes the major
sources/activities in the Virgin Islands which are of concern.
Generally, the most significant pollutant sources in the
Virgin Islands include municipal discharges, sediment runoff
from urban areas and development zones, and inadequate surface
water resources. Toxics and nutrient related problems are
of very low priority islandwide.
St. Thomas - The two major waterways which have been adversely
affected by conventional pollutant sources are Charlotte
Amalie Harbor and the Mangrove Lagoon.
Water quality data indicate that conditions in St. Thomas harbor
have improved over the last few years. Fecal coliform levels
have decreased, Secchi depths (water clarity) have increased
and DO levels have also improved. The last raw discharge to
Charlotte Amalie Harbor has also been eliminated by the
construction of a collection system to service the Sub-Base
sector of St. Thomas.
Three conditions which still exist, however, and which con-
tinue to adversely affect the clarity and bacterial levels
in the harbor are: 1) silt resuspension by cruise ship traffic,
2) deterioration of the Charlotte Amalie collection system
and, 3) illegal sanitary connections to the storm sewer system.
The latter two conditions have elevated bacterial levels in
localized sections of the harbor. In addition, the impact
of discharges of sanitary waste from pleasure crafts on the
harbor is currently being assessed.
Water quality and biological conditions in the Mangrove Lagoon
have also deteriorated over the last few years. This previously
unique biological resource which represents the only large
mangrove community in the Virgin Islands has experienced a
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TABLE 1
Summary of Source Control Problems by Segments
St. Thomas | St. John | St. Croix
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15
16.
17.
18.
19.
20.
21.
22.
23.
Municipal Discharges
Direct Industrial Discharges
Indirect Industrial Discharges
Municipal and Industrial
Was'.e Sludges
Combined Sewer Overflows
Thermal Discharge/Entrainment
Urban Storm Runoff
Construction-Related Runoff
Mining-Related Runoff
Agricultural-Related Runoff
Silviculture-Related Runoff
Aninal Waste
On-Lot Disposal
In-Place Pollutants
Oil and Hazardous Substance
Spills
Vessel Wastes
Dredging Operations
Saltwater Intrusion
Hydrologic Modification
Water Supply Quantity
Water Supply Quality
Environmentally Unsound
Development
Radioactive Wastes
H
L
L
M
L
L
M
M
L
L
L
L
M
L
L
M
L
M
M
H
M
M
L
M
L
L
L
L
L
M
M
L
L
L
L
M
L .
L
L
L
L
L
M
L
L
L
M
L
L
L
L
L
M
M
L
L
L
L
M
L
L
L
M
M
M
H
M
M
L
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shift from a grass bed, benthic plant-dominated, clear embayment
to a highly turbid, plankton-dominated system. The two
factors primarily responsible are:
(1) Direct discharge of partially treated sewage from the
Nadir sewage treatment facility into the Mangrove Lagoon,
discharge of partially treated sewage into Turpentine
Run from the Donoe, Old Tutu, and New Tutu sewage treatment
facilities, and an increase of the population living on
outboard boats and an increase in marina activities, -end-
(2) Elimination of large portions of the mangrove forests
forming the Turpentine Run Delta by fill operations and
channelling storm runoff with its high sediment load
directly into the lagoon.
St. John - Monitoring data indicate that with a few exceptions
water quality conditions in St. John are excellent and have
remained so over the last few years.
With the completion of a sewerage system at Cruz Bay, water
quality should be restored in the Creek area of the bay and
occasional violations of standards should be eliminated.
However, one sector of St. John's coastal water is of some
concern. At Coral Bay, a very large bay near the island's
eastern end, increased runoff of storm waters from steep
slopes surrounding the bay now causes visible high turbidity
in the receiving waters. Development of marina facilities
and associated activities along the bay have and will likely
continue to adversely affect quality in the bay. The need for
an improved land management program for this region is obvious.
St. Croix - Water quality in Christiansted Harbor has sig-
nificantly improved due to the construction of the St. Croix
primary POTW and related collection system. Fecal coliform
levels have fallen dramatically and instream DO levels have
risen; deterioration of portions of the collection system
and illegal connections to the storm sewer system, however,
continue to suppress instream quality to a certain extent.
Significant improvements in instream quality and benthic
viability have also been recorded along the south shore of
St. Croix; some reef areas are still adversely affected,
however, due to high turbidity levels. The Virgin Islands
Rum, Ltd. discharge near the southwest corner of the island
also causes a highly visible effluent plume that moves to the
west along the south coast and is discernible for a few miles
down current. Its biological and water quality impacts are
apparently localized near the discharge site.
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Finally, the 10,000 foot St. Croix municipal outfall extending
off the south shore is broken at a point 2500 feet offshore;
this Jfracture results in poor instream effluent dilution and
may b« causing localized water quality problems.
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SURFACE DRINKING WATER AND GROUNDWATER
STATUS OF PUBLIC WATER SUPPLY SYSTEMS
Provision of drinking water of sufficient quantity and good
quality is probably the greatest environmental challenge in
the Virgin Islands. The sources of drinking water are de-
salted seawater, rainwater, and groundwater.
There are 564 active public water supplies throughout the
Virgin Islands. The characteristics of the systems are
shown in Figure 2. The majority (98 percent) of the population
uses desalted seawater and rainwater catchments as the
primary sources of drinking water. The remainder uses groundwater.
As shown in Figure 3, there are numerous small and very
small systems throughout the islands.
FIGURE 2
PUBLIC WflTER SYSTEMS
VIRGIN ISLflNDS
PWS SOURCE
PWSTYPe
NON-COMMUNITY PWS
378 (67%)
POWUTJON SERVED
SURFRCE HflTER
182 (967.)
SURFRCE WflTER
(99%)
Overall, the quality of drinking water provided in these
public water supply systems is poor. In 1981, only 17
percent of the systems were in full compliance with the
national drinking water standards pertaining to micro-
biological quality; 56 percent were intermittent violators
and 27 percent were persistent violators (Figure 4). In the
same year, only 42 percent of the systems met the turbidity
standard; 50 percent were intermittent violators, and 8
percent were persistent violators (Figure 5).
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FIGURE 3
12S«|
SIZE DISTRIBUTION OF CNS'S
VIRGIN ISLRNDS
527.
Legend
CZ3 CWS'e
•• POP SERVED
SIZE CRTEGORY
FIGURE 4
COMMUNITY PUS'S WITH BRCTI VIOLRTIONS
VIRGIN ISLRNDS
ZERO 1-3 >3
NUMBER OF VIOLRTIONS
Legend
1980
1981
10
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FIGURE 5
COMMUNITY PWS'S WITH TURBIDITY VIOLATIONS
VIRGIN ISLRNDS
SOX
Legend
EZ2 1980
•i 1981
ZERO 1-3 >3
NUMBER OF VIOLRTIONS
Overall compliance improves with larger size systems. Figures
J? and 7 show this relationship. The higher violation rates
occur in the smallest size systems. In all categories, for
both microbiological and turbidity, compliance is about the
same for 1980 and 1981.
With regard to inorganic contaminants, all community systems
were analyzed in 1982 for the inorganic chemicals specified
in the drinking water standards. No significant levels were
found in the systems except for sodium which was found in
most of the supplies. As for the organic contaminants, 15
percent of the systems were sampled and analyzed in 1982 with
the remainder scheduled for early 1983. Thus far, none of
the pesticide or herbicide contaminants specified in the
drinking water standards have been detected. No data are
available on the radiation contaminants specified in drinking
water standards.
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FIGURE 6
PESCENTRGE OF COMMUNITY PWS'S IN VIOLRTION FOR BRCTI
VIRGIN ISLflNDS
ao -i
7V/.
CS
CC
E—'
QJ
CD
ce:
UJ
I Q_
20-
Legend
eza 1980
IB 1981
SIZE CflTEGORY
FIGURE 7
PE^CENTflSE OF COMMUNITY PWS'S IN VIOLATION FOR TURBIDITY
VIRGIN ISLflNDS
75-1
UJ
cs
a:
UJ
CJ)
&;
UJ
o_
' Legend
EZ 1980
•• 1981
SIZE CATEGORY
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Use of fresh groundwater wells and a conventional distribution
system as the source of supply is the most cost-effective,
implement able program for St. John.
St. Croix - The fresh groundwater resources are not adequate
to supply the raw water needs of the public water supply
system on St. Croix. The brackish groundwater reserves in
the Kingshill marl aquifer are capable of supporting the
public system's demand. Brackish ground water treated by
reverse osmosis may be a future source of water supply.
Surface water resources are inadequate to play a direct role
in supplying water to the public water supply system. The
continued use of impoundments and ponds for stock watering
and crop irrigation is the best use of this resource. Hillside
catchments and storage are also inadequate and unreliable
as a source of water for the public system. Rehabilitation
of abandoned catchments on St. Croix is not cost-effective.
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GROUNDWATER SOURCES OF DRINKING WATER
Although groundwater supplies are used by only two percent of
the population, it is an important drinking water source,
especially in inland areas. The three major factors that
affect: the quality of groundwater are mineral concentrations,
solubi.e substances, and saltwater intrusion. The minerals
contained in ground water are concentrated by the high rate
of evaporation. The most significant of these is chloride.
Ground water is largely affected by soluble substances through
which it passes in the ground before being recovered. It
picks up additional carbon dioxide, tannic acid and organic
matter from the decomposition of organic material in the
soil, which lowers its pH. Saltwater intrusion occurs in
the form of a seawater wedge moving inward into confined
aquifers. Saltwater intrusion can be aggravated by overpumping
such aquifers.
While the groundwater quality is quite variable and yields
are small, the severe water shortages and increasing demand
factors require pumping of all wells to the limit of the
resource on both St. Thomas and St. Croix. There have been
several cases of overpumping and subsequent contamination of
aquifers by saltwater.
Because mineralization increases with proximity to shorelines,
the quality of water from upland wells is generally better than
that from lowland wells in alluvial plains or near coastal
marshes or lagoons. However, mineralization of groundwater
in tho few central valleys can also be high where evaportrans-
piration concentrates minerals carried in rainwater, and where
septic tank effluents drain into valley alluvium. The quality of
groundwater on all three islands is adequate for watering
livestock and for crop irrigation, and some wells on each
island are pumped daily for these uses.
St. Tnomas - The fresh groundwater resources are not adequate
to supply the raw water needs of the public system on St. Thomas.
The surface water resources are inadequate to play a direct
role in supplying water for the public system. Hillside
catchments and storage are ineffective in providing a reliable,
safe yield to the public system. There are abandoned catchment
areas on the island, but the cost of rehabilation and public
health protection have made use of these sites impractical.
Use of distilled sea water as the primary source of water is
the most cost-effective and implementable program on St. Thomas.
St. John - The fresh groundwater resources in the island's
interior are considered adequate to serve the needs of the
public water supply system. However, surface water resources
are not considered adequate for this purpose. Farm ponds
will continue to serve the water needs for livestock and limited
crop irrigation.
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PRIORITY DRINKING WATER PROBLEMS
° Insufficient Quantity
Although the Virgin Islands are no longer experiencing the
chronic and serious water shortages of prior years, major
water supply problems remain? problems include the cost of
water quality, the quality of water, a deteriorated distribution
system, the need for an improved accountability system, and
the need for an overall systematized management and decision
making approach to water supply.
These problems exist in the Virgin Islands because of lack of
conventional water supply sources such as groundwater and
surface bodies of water. As a result, the Virgin Islands
purveyors must depend primarily upon desalted sea water and
catchment of rainwater as sources for drinking water. Prior to
the recent installaton of new desalinization units on St. Croix
and St. Thomas, the dependability of desalted sea water was
unreliable because the previous units were deteriorated and
experienced frequent breakdowns. With the installation of the
new units, the quantity problem has been reduced substantially
in the areas serv.ed by central water distribution systems.
Quantity problems persist in the remaining islands where
purveyors are dependent upon catchment of rainwater, supple-
mented by trucked-in water from the central systems.
St. John, with its smaller population, experiences fewer problems
with its water supply. St. John utilizes fresh groundwater
resources from the island's interior to serve the needs of its
public water supply system which is supplemented as needed by
barging from St. Thomas.
Water supply quantity problems still remain in remote areas of
the islands. These problems include the feasibility of extending
transmission mains or locating desalinization treatment units
in remote areas and the reluctance of purveyors to discontinue
use of low cost rainwater.
0 Persistent Violations in Public Water Supply Systems
Water quality problems in the Virgin Islands Housing Authority
(VIHA) projects, located on both St. Croix and St. Thomas, are
critical. An estimated population of 18,000 living in the 80
projects are supplied water which consistently violates the
territorial standards for turbidity and coliforms. The nature
of the catchment system in the projects, inadequate disinfection,
turbidity interference with disinfection, and infiltration
because of inadequate pressures in the distribution system are
the prime reasons for the water quality problems.
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HAZARDOUS WASTES
There is only one generator in the Virgin Islands which
handles sufficient amounts of hazardous wastes to bring it
under the RCRA regulations. This generator appears to have
adequate on-site treatment and disposal capacity.
However, the Virgin Islands does have pressing problems
relating to the disposal of non-hazardous municipal wastes.
The bulk of this material will go to two proposed resource
recovery and desalinization projects, pending approval.
The Virgin Islands Department of Conservation and Cultural
Affairs is currently evaluating whether it should establish a
local hazardous waste regulatory program. Small quantities
of dry cleaning and degreasing solvents, waste oils, and
possibly PCBs from the Virgin Islands Water and Power Authority
may present a significant problem.
There e.re no uncontrolled hazardous waste sites in the Virgin
Islands.
PESTICIDES •
The EPA pesticide programs are directed toward oversite of
the federally-funded, state-implemented programs.
The Virgin Islands program is mainly concerned with the
certification of pesticide applicators, inspection of imports
to ascertain their meeting all legal requirements, and the
inspection and monitoring of applicators to assure safe
storace, handlinng and proper use of pesticides.
There are no pesticide producer establishments on the Virgin
Islands.
Pesticides enforcement priorities in the Virgin islands are
determined through an evaluation of "percent harm" from
various categories of pesticide applicators. There has been
no reported harm from general pest control involving various
pesticide and termite treatments, even though some misuse
episodes occurred. The primary enforcement activity in the
Virgin Islands will be an examination of pesticide use on
vegetable and livestock (dairy) farms, with specific attention
to those pesticides cited in consumer complaints.
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RADIATION
There are no nuclear power plants, ore processing or storage
facilities, or radiological monitoring sites on the Virgin
Islands.
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