United States Office of
Environmental Protection Emergency and
Agency Remedial Response
EPA/ROD/R03-91/126
Seotember 1991
&EPA Superfund
Record of Decision:
USA Aberdeen, Michaelsville,
MD
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50272-101
REPORT DOCUMENTATION
PAGE
1. RBKMTNO.
EPA/ROD/R03-91/126
i. Recipient1* Acce»*lon No.
4. TM*andSi*H*
•UJPERFUND RECORD OF DECISION
A Aberdeen, Michaelsville, MD
First Remedial Action - Final
S. Report Date
09/27/91
7. AuVion»
a. Performing Organization RepL No.
9. Performing OrgaWzafion Nam. end Addrea*
10. Pro)ecVTa*k/Work Ontt No.
11. ContncqC) or Oant(G) No.
(C)
(0
12. Sponsoring Organteaflon Nam* and Addr***
U.S. Environmental Protection Agency
401 M Street, S.W.
Washington, D.C. 20460
13. Type of Report & Period Covered
800/000
14.
15. Supple
iryNo
16. Abstract (Umte 200 word*)
The 79,000-acre USA Aberdeen site, also known as the U.S. Army Aberdeen Proving
Ground (APG) , is an active military installation used since 1917 for planning and
testing weapons, munitions, vehicles, and equipment in Harford County, Maryland, near
the head of the Chesapeake Bay. APG is divided into two functional areas: the
13,000-acre Edgewood Area and the 17,000-acre Aberdeen Area, which includes two
•^ndfills. These two areas are divided and drained by Bush River, as well as by
merous creeks. From 1922 to 1925, an unknown amount of World War I white
t/nosphorus munitions (ordnance) was supposedly buried offshore of the Aberdeen Area
on the western side of the upper Chesapeake Bay. This 15-acre area, termed the White
Phosphorus Underwater Munitions Burial Area (WPUMBA) , is the focus of this ROD. The
ordnance reportedly buried at the WPUMBA consisted of land mines, grenades, and
artillery shells; in addition, bulk phosphorus may have been buried. In 1933, the
WPUMBA was reportedly uncovered by a hurricane, resulting in a large waterfowl kill.
However, no evidence of a disposal site at the WPUMBA was observed in historical or
aerial photographs, and only one reference to the disposal area has been found. In
addition to background searches, EPA conducted extensive electromagnetic and core
(See Attached Page)
17. Document Analyala a. Descriptor*
Record of Decision - USA Aberdeen, Michaelsville, MD
First Remedial Action - Final
Contaminated Media: None
Key Contaminants: None
h. ldBf)Mera/Qp0fvEnd0d Twins
e. COSATI FMd/Grav
ia tanabBty Statement
19. Security CUa* (Trite Report)
None
20. Security Cta*» (This Page)
None
21. No. oi Page*
17
22. Price
(SeeANSJ-Z3S.18)
Stt bvtructlont on fltwana*
OPTIONAL FORM 272 (4-77)
(Formerly NT1S-35)
Department of Commerce
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EPA/ROD/R03-91/126
USA Aberdeen, Michaelsville, MD
First Remedial Action - Final
a tract (Continued)
sampling studies of the WPUMBA from 1988 to 1989. Sample results revealed only trace
amounts of white phosphorus and only sporadic magnetic objects in sediment, and no
phosphorus in surface water. Hence, no effective remedial action is possible at the
site. Future RODs may be warranted if contamination is found. Therefore, there are no
primary contaminants of concern affecting the site.
The selected remedial action for this site is no action with surface water monitoring
after severe storms with hurricane strength winds or any other act which may disturb
sediment. Water samples will be analyzed for phosphorus, using a detection limit of
0.01 ug/1, which is 10 percent of the established toxicity concentrations approved by
EPA, and for metals using EPA detection limits. There are no present worth or O&M
costs associated with this no action remedy.
PERFORMANCE STANDARDS OR GOALS! Not applicable.
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EPA
WHITE PHOSPHORUS
UNDERWATER MUNITIONS
BURIAL AREA
RECORD OF DECISION
SEPTEMBER 1991
ABERDEEN PROVING GROUND, MD
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BKCQRD OF DBCISIOH
•hit* Phaephons Underwater
Burial Arc*
Operable Unit
U.S. Army Aberdeen Proving Ground, Maryland
September, 1991
Whit* Phosphorus Underwater Munition* Burial Area
U.S. Army Aberdeen Proving Ground, Maryland
This decision document presents a determination that no remedial action will be taken at this time for tha
Whit* Phosphorus Underwater Munitions Burial Araa (WPUMBA) at tha U.S. Any Abardaan Proving -.round, Maryland.
This determination was developed in accordance with the Comprehensive Environments! Response :oopensation and
Liability Act of 1980 (CERCLA), as amended by the Superfund Amendment and Raauthorisation Ac; of 1986 (SARA),
42 D.8.C. Section 9601 et seq. and the national Contingency Plan (HCP) 40 C.F.R. Part 300. This no action
decision is supported by~d*ocuments contained in the administrative record. The State of Maryland has concurred
on the no action determination.
The no action decision is based upon the fact that the supposed white phosphorus contamination at the NPOMBA
was never found using current available technology, and that no affective remedial action ia possible at the
eite. The no action remedy calls for sampling of the water column in the WPUMBA vicinity prior to and during
any dredging activities in the area, and following major storm events (hurricane force winds), to monitor and
minimise releases of sediment-bound materials to the environment.
Currently, the WPUMBA presents a minimal risk to the human population and the environment. However, the
monitoring requirement of the no action remedy does not provide any protection against release of or exposure
to white phosphorus from WPUMBA in the future. Therefore, the.no action decision does not constitute a finding
that tha remedy ensures adequate protection of human health or the environment. Because the no action remedy
could result in possible undetected hatardous substance* remaining in the sediment and being released to the
environment in the future, a review will be conducted five years after the finalimation of this decision. This
review will identify possible technological advances that might be developed which have a greater
detection/location capability for white phosphorus than currently exists today to warrant a re-investigation
of the supposed underwater burial area.
Additionally, the Army and IPA are proposing, with the issuance of this Record of Decision for the WPUMBA,
to initiate an investigation of a possible site on land or in a tidal marsh to be designated the "White
Phosphorus Munitions Land Burial Area (WPMLBA). • The investigation of the WPMLBA will be incorporated into the
Other Aberdeen Areas Study.
Date
onald V. Bite
Brigadier General
Commanding
Aberdeen Proving Ground
.8. Army
Lewis D. Walker
Deputy for Environment, Safety, and Occupational Health
Office of the Assistant Secretary of the Army
U.S. Department of the Army
.n B. Brickaon
Regional Administrator
U.S. Environmental Protection Agency - Region
III
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SUMMARY OF REMEDIAL ACTION SELECTION
White Phosphorus Underwater M*""**0™ Burial Area
U.S. Army Aberdeen Proving Ground, Maryland
SITE DESCRIPTION:
U.S. Army Aberdeen Proving Ground (APG) occupies some 79,000 acres of land and water in southern
Harford County and southeastern Baltimore County, Maryland, near the head of the Chesapeake Bay (See
Figures 1 & 2). It is owned and operated by the U.S. Department of the Army (Army) and is an active
Army test and evaluation installation primarily responsible for planning and testing of weapons, munitions,
vehicles, and various equipment. APG consists of two functional areas: The Edgewood Area (13,000 land
acres, including Gunpowder Neck, Pooles Island, Carroll Island, and Graces Quarters) and the Aberdeen
Area (17,000 land acres, including Michaelsville and Phillips Landfills). The land portions of the two areas
are separated by the Bush River. (See Figure 3)
The Aberdeen area is bordered on the west by the Bush River and northeast to south by the Chesapeake
Bay. The area is drained by seven creeks plus the Bush River. Most of these creeks have their headwaters
on the Aberdeen Area The Army facilities in the Aberdeen area include firing ranges, impact areas, vehicle
test tracks, and laboratories in support of testing activities.
The White Phosphorus Underwater Munitions Burial Area (WPUMBA) is located offshore of the
Aberdeen area of APG, Maryland, on the western side of the upper Chesapeake Bay. The area is situated
in shallow waters just beyond the mouth of Mosquito Creek, between Black Point and Gull Island (See
Figure 4). Spesutie Narrows and Spesutie Island lie to the north and northeast, respectively. The open
water area of APG totals approximately 37,000 acres of which 15 acres of open water comprise the
supposed WPUMBA.
Based on interviews of former employees who worked on the post following World War I, an unknown
amount of World War I white phosphorus munitions (ordnance) were supposedly buried in the Chesapeake
Bay in the vicinity of Black Point during the period 1922-1925. The ordnance reportedly consisted of
United States, British, and French land mines, grenades, and artillery shells. According to the interviews,
bulk phosphorus may also have been disposed in the Bay. It is possible that this disposal event involved
a single barge load of munitions; however, it may have involved considerably more. In 1933, the WPUMBA
was reportedly uncovered by a strong hurricane, which led to a large waterfowl kill, where ducks
supposedly "turned pink and died*
The U. S. Environmental Protection Agency (EPA) issued APG a Resource Conservation and Recovery
Act (RCRA) Corrective Action Permit, on September 30,1986, as modified on September 26, 1988. The
EPA and the Army entered into a Comprehensive Environmental Response, Compensation, and Liability
Act (CERCLA), Section 120 Interagency Agreement GAG) on March 27,1990, to coordinate and provide
for aD CERCLA/RCRA corrective action activities at APG. In this IAG, the Army and EPA agreed that all
areas which were identified as RCRA corrective action study areas would be investigated and, if necessary,
remediated pursuant to CERCLA. The WPUMBA was identified as a RCRA corrective action study area.
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[RAKPOHQ COUNTY
AIM "AAV! DE GftACl
Figur.
Location of Aberdeen Proving Ground, Maryland
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HARFORD COUNTY,
MARYLAND
HW PMmi«i
Mm tamp T
7. OMfMNr SM MM
• • VIM
M
•
Figure 2
Location of AM2 in Harfoid County. Mirytend
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ABERDEEN PROVING GROUND
AREAS OF INTEREST
WHITE OUTLINE - FOGEWOOO AREA
BLACK OUTLINE - ABERDEEN AREA
234
SCALE (IMLESI
Figure 3
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'. AMPHIBIOUS. .
•v LANDING- •;.'•:
JOHNSON- .••.-•.-;
POINT .1 •:• •:• •;•
•MUL3ERRY
' •. »C1NT '.'
MULBERRY POINT •-.••.-
xv •/••DOCK •;. -;.'•.'•'•:•
•' cuu.VV •'. .•.-•. -• -V -•: -: •'
su
PHOSPHORUS.
UNDERWATER MUNITIONS
•:••:BURIAL "ARIA.
MOSQUITO C3SX
CHSAPEAKE BAY
"- '.'•
LOCATION OF SUPPOSED WHITE PHOSPHORUS
UNDERWATER MUNITIONS BURIAL AREA
."' . SCALE - f-730* ' |t*NO
PREPARED FOR:
ENVJRONUENTAL MANAGEMENT
OtMSON
ABERDEEN PROVING GROUND. MARYLAND
•AT
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arris HISTORY
The Aberdeen Area of APG was established in 1917 as the Ordnance Proving Ground. Testing of
ammunition began in January of 1918. Large segments of the open water surrounding the Aberdeen Area
have been used as ordnance impact areas since 1917. There are an estimated four million unexploded and
sixteen mffl'«™ inert projectiles of all calibers in the restricted waters off APG.
The WPUMBA is adjacent to and offshore of the Main Front Land Range Area, which has been active
since 1917. An estimated one million rounds of all calibers up to 16 inches have been fired at this range.
The types of rounds fired include high explosives, anti-personnel, armor defeating, incendiary, smoke, and
illuminating. Although the WPUMBA is adjacent to this range, there are no records of the open water
areas of the WPUMBA having been used as an impact area.
No evidence of a disposal site at the WPUMBA was observed in any historical aerial photographs
reviewed. However, one reference to a phosphorus area was found in Proclamation 2383, signed by
President Franklin D. Roosevelt on January 24, 1940. Under the authority of the Migratory Bird Act of
1918 (40 Stat 755, 16 U.S.C. 704), the acting Secretary of the Interior adopted a regulation on December
12, 1939, which designated two areas as Migratory Waterfowl Closed Areas. One of the areas approved
by the subsequent Proclamation was at APG and was referred to as the "Phosphorus Area Unit." This
Proclamation is the only written document found that specifically mentions phosphorus and delineates the
boundary of a specific area. The size of this "Phosphorus Area Unit" encompasses approximately 130 acres.
It is assumed that the area described incorporated the WPUMBA.
During 1988-1989, the EPA's Environmental Response Team (ERT) and Environmental Monitoring
Service Lab conducted extensive electromagnetic and core sampling studies of the WPUMBA. The EPA
ERT investigation was conducted as a CERCLA Remedial Investigation to answer questions related to; the
location of the WPUMBA; possible releases to the environment surrounding the supposed burial site;
potential adverse effects to the environment, aquatic organisms, higher food chain organisms, and humar,
health that could result should there be a release from the area; the extent to which any past, present,
or future dredging activities may contribute to releases from this area; and meet the requirements of the
IAG.
Several techniques were used during the investigation to determine the location of the WPUMBA. A
literature search was conducted to locate related information concerning the disposal, storage, and handling
of white phosphorus. APG records, historical maps,and aerial photos were reviewed. Manufacturers, former
employees, and historians (National Archives, Library of Congress, U.S. Army Archives) were also
contacted for relevant information. An in-depth geophysical investigation at the site was conducted in
October, 1988, followed by an additional geophysical survey in June of 1989.
Based on the 1988 geophysical data, four areas were selected as being highly probable locations for the
WPUMBA, and sediment core sampling was scheduled for those areas. A fifth area, the channel adjacent
to the WPUMBA, was selected for coring due to maintenance dredging concerns. A reference area was also
selected north of the she in Spesutie Narrows. Due to the safety concerns in dealing with the burial area
and the known presence of unexploded ordnance on APG, a remote coring operation was necessary.
A total of 60 cores were collected during August of 1989, ranging in depth from 1 to approximately 9 feet.
Cores were screened on-site for high explosives and composite samples were collected for analysis. All
samples were analyzed for elemental phosphorus, high explosives, and RCRA hazardous wastes. Select
samples were analyzed for total organic carbon, grain size, and toritity. Water samples were also collected
at each of the areas cored and analyzed for elemental phosphorus and high explosives. Water quality
measurements were recorded in P»I»II area and included temperature, pH, conductivity, salinity, oxidation-
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reduction potential, and dissolved oxygen.
Gull Island, which is located along the eastern border of the WPUMBA, was examined as a potential past
disposal site for white phosphorus. A geophysical survey was conducted in late October of 1988 to locate
any potentially buried ferrous metals. Several test pits were excavated to examine the stratigraphy and
soils of the island. Soil cores were collected during September of 1989 from the north and south ends of
the island and analyzed for elemental phosphorus, high explosives, and grain size.
Based on the results of the EPA ERT study, the boundaries of the WPUMBA could not be discerned.
The geophysical investigation showed only a minor distribution of magnetic objects, and intrusive sediment
core sampling revealed only sporadic occurrences of detectable levels of phosphorus. Results indicate that
trace amounts of phosphorus were detected in 11 of the 60 core samples, with the detected single
maximum occurrence being less than 5 pg/kg (See Table 1). No phosphorus was detected in the water
column, or on Gull Island. No high explosive compounds were detected in the water or sediment samples.
RCRA analyses (EP Toxitity) indicate that the sediment would not be considered a hazardous waste.
Release of white phosphorus is not expected unless the sediments are disturbed. The location of the
WPUMBA could not, therefore, be determined within the confines of the EPA ERT study. Likewise,
bioassay techniques, utilizing freshwater and estuarine fish, did not elucidate any dear toxic effect of white
phosphorus on aquatic life.
COMMUNITY PAHTKHPATION
To provide the community with reasonable opportunity to submit written and oral comments on the
Proposed Plan for the White Phosphorus Underwater Munitions Burial Area and the U.S. EPA
Environmental Response Team's (ERT) report, entitled "Field Investigation of the White Phosphorus
Munitions Burial Area, Aberdeen Proving Ground, Maryland • January, 1990" the Army established a
public comment period from July 3rd through August 17th, 1991. A public meeting was held on July 25,
1991 to present the Proposed Plan and to answer questions and receive comments.
The Proposed Plan, EPA ERT's report, and the Administrative Record file were made available for public
review at the following locations:
On-Post
U.S. Army Test and Evaluation Command
Public Affairs Office Building 314
Aberdeen Area
Aberdeen Proving Ground, MD. 21005-5001
Off-Post .
Harford County Library • Aberdeen Branch Library
21 Franklin Street
Aberdeen, Maryland 21001
Harford County Library • Edgewood Branch Library
2205 Hanson Road
Edgewood, Maryland 21040
Legal notices summarizing the Proposed Plan, informing the public of document availability and locations,
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TABLE 1.
Location
Area I
Black Point
Black Point
Black Point
Black Point
Black Point
Channel
Area II
Area III
Area III
Area III
RESULTS OF ELEMENTAL PHOSPHORUS ANALYSIS IN SEDIMENTS
White Phosphorus Underwater Munitions Burlsl Ares
Aberdeen Proving Ground, Maryland
August, 1989
Core
3
11
17
18
20
25
31
40
54
55
58
Sample?
4356
4427
4433
4434
4436
4441
4448
4457
4475
4476
4480
Phosphorus
Dry weight
(Mg/kg)
0.78
2.22
0.72
0.62
2.22
1.16
0.74
2.41 '•
4.64
3.38
3.84
Phosphorus
Wet Weight
(Mg/fcg)
0.42
1.00
0.30
0.28
0.71
0.94
0.34
1.04
1.90
1.55
1.80
Core
Length
(ft)
4.5
4
4.5
4.5
5.5
< 1
6
8.5
6
6
9
from ERT study 'F/e/d /nvestioation of tf» White Phosphorus
Munitions Burial An*. Jan. 1990.
*
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and listing the time and place of the public meeting, were published in The Baltimore Sun. The Aegis, and
The APG News. No comments were received by the EPA, State of Maryland, or the Army during the
public comment period on the Proposed Plan, on the EPA ERT's report, on the no-action alternative
chosen for the White Phosphorus Underwater Munitions Burial Area, or on the Administrative Record file.
Several technical questions were answered during the public meeting concerning the conduct of the ERT
investigation.
SCOPE AND BOLE OP THE WPUMBA OPERABLE UNIT RESPONSE ACTION
The investigation of the WPUMBA answered questions related to conditions at the underwater site, and
the potential for current and future threats to human health and the environment. The location and
existence of the WPUMBA in the ERT study area has not been confirmed, using the best available
technology. The Army and the EPA wfll conduct a review, five years hence, of the technology available for
the detection/location of white phosphorus to determine if any significant advancement has occurred to
warrant a re-investigation of the supposed burial area
The lark of detectable quantities of phosphorus in the water column, combined with the relatively low
concentrations of phosphorus found in less than 20% of the sediment samples and the depth at which
phosphorus was detected, indicates that white phosphorus is not being released into the water column at
the study area. Additionally, RCRA analyses (EP Tenacity) indicate that the WPUMBA sediment would not
be classified as a hazardous waste. However, the "no action" remedy does not provide any protection
against exposure to white phosphorus if it is later released from the yet undiscovered WPUMBA. The "no
action" remedy, therefore, requires monitoring of the WPUMBA by the Army during dredging and
following major storm events.
It is still possible, however, that unexploded ordnance or other safety hazards may exist within the study
area. The goals, therefore, of the selected remedial action are to 'limit the exposure of the aquatic
ecosystem and human population to any buried material contained in the current WPUMBA, and are to
be accomplished through the above described monitoring/sampling program. Additionally, a review of the
technology available for detecting and locating the supposed WPUMBA will be performed in five years.
Therefore, the Army and the EPA have agreed that the ERT investigation demonstrated that the
supposed WPUMBA could not be located in the study area outline in Figure 4. However, historical
references recently reviewed by the Maryland Department of the Environment indicate the possibility of
another location for a white phosphorus burial site, in addition to the ERT underwater study location. The
phosphorus burial reportedly occurred in the waterfront region near Black Point, encompassing an area
of 15 acres. One historical reference alludes that when disposed, the munitions were placed in tidal flats
and covered with 2 feet of sediment. The Army and EPA have agreed, with the issuance of this Record
of Decision (ROD) for the WPUMBA, to initiate an investigation of a possible site on land or in a tidal
marsh near Black Point, to be designated the "White Phosphorus Munitions Land Burial Area (WPMLBA) ."
Figure 5 depicts the proposed new study area. The investigation of the WPMLBA wfll be incorporated into
the Other Aberdeen Areas Study.
BtTJS
APG is located on the northwestern shore of the Chesapeake Bay. Due to its proximity to two large
bodies of water, the Chesapeake Bay and the Atlantic Ocean, the climate at APG tends to be moderate
as compared to inland Maryland. The average temperature for APG is 54.5 *F, with an average relative
10
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I I LAND
UNO
ESI UNDER
INVESTIGATION
LOCATION Of WHITE PHOSPHORUS MUNITIONS LAND BURIAL
AREA ID BE INVESTIGATED UNDER THE OTHER
ABERDEQJ AREAS UNIT
flCURE 5 ' SCALE - I'-MO"
PREPARED FOR:
ENVIRONMENTAL MANAGEMENT
DIVISION
ABERDEEN PROVING GROUND. MARYLAND
•AT X
11
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humidity of 73.8%. Precipitation as rainfall averages 38.58 inches with a maximum rainfall occurring during
the summer and the minimum rainfall occurring during autumn Precipitation as snowfall averages 12
inches. Prevailing winds average 6.8 knots in a northwest to north-northwest direction in the winter
months, and a south to south-southwest direction in the summer months.
APG is drained by eight rivers and streams. Surface waters at APG tend to be shallow and sluggish with
tidal estuaries forming at the mouths of the streams and rivers. This is attributed to low land elevations
and the fact that APG is bordered by the Chesapeake Bay. The northeastern area of APG, which tends
to be highly developed, is drained by Swan Creek, Dipple Creek, Woodrest Creek, and the upper branches
of Romney Creek. The southwestern portion, which tends to be undeveloped and includes some ranges and
test areas, is drained by Mosquito Creek, Delph Creek, the lower half of Romney Creek, and the lower
portion of Bush River. Spesutie Island, which is also undeveloped and includes test areas, is drained by
Back Creek.
Alluvium, swamp and marsh deposits occur in the reaches of the rivers in the region that have become
inundated as a result of a rise in sea level Composition of the Alluvium ranges from clay to gravel, and
the swamp and marsh deposits consist of silts, clays, and organic matter. Thus, surficial sediments are
heterogeneous and vary considerably in the lateral direction. Typically, gravels are at the base and the silts
and clays dominate the upper portions.
SUMMARY OF SITE RISKS
Physical and Chemical Properties of White Phosphorus
Phosphorus is a very reactive element, and thus it is never found in the free state in nature, but is widely
distributed in mineral deposits. Elemental phosphorus exists in three allotropic modifications; white, red,
and black, the most common form being white phosphorus. White phosphorus, which may have a slight
yellow hue, is both poisonous and flammable, and is the most reactive of the three allotropes. This
reactivity may result from white phosphorus maintaining its tetrahedral structure throughout its phase
changes. At room temperature, white phosphorus exists as cubic crystals, called the alpha (a) form. White
phosphorus' ignition temperature is only 86-F. It is a soft, waxy, translucent solid which is soluble in
organic solvents, such as carbon disulfide, but is unreactive with water. White phosphorus has a high
octanol/water partition coefficient which reveals a potential for bioaccumulation, and a high volatility which
indicates some potential for release to the atmosphere. Elemental white phosphorus is tetratomic, having
a molecular weight of 123.90, and the chemical formula P4.
When exposed to air, white phosphorus fumes and spontaneously ignites with an odor somewhat like that
of a burning match. Lake carbon, phosphorus burns as a solid without vaporizing. The combustion forms
either tetraphosphorus hexoxide or tetraphosphorus decoxide:
P4 + 302 - P4O6
P4 + 502 - P4010
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Tetraphosphorus decozide dissolves in water to form the mineral acid known as phosphoric acid:
P4O10 + 6H2O - 4H3P04
To prevent its spontaneous ignition, white phosphorus is normally stored under water, which keeps it
from contact with air. Because of its low ignition temperature, white phosphorus ignites so easily that it
is unsafe to handle out of water. It is also unstable, gradually changing to red phosphorus, which is less
reactive.
Fires involving elemental phosphorus are extinguished with water or blanketed with wet sand or
absorbent. However, it is important to recall that the oxides of phosphorus which result from combustion
are capable of forming corrosive acids when they dissolve in water. Thus the atmosphere surrounding a
phosphorus fire is likely to be acidic. Inhalation of the fumes of burning phosphorus can lead to serious
lung injury when the oxides dissolve in the liquid within the lung and associated passages. White
phosphorus is also known to cause phossy jaw (phosphorus necrosis), a rotting of the jawbone.
Three analytical methods used for the detection of white phosphorus, listed in descending order of
sensitivity, are: neutron activation analysis, gas-liquid chromatography, and colorimetry. The most
commonly used analytical technique in aquatic surveys and bioassays is gas-liquid chromatography.
-a
Toxicology
It is known that white phosphorus is a powerful systemic poison. It is absorbed through the skin, by
ingestion, and through the respiratory tract The lethal dose (oral ingestion) in adult humans is about 1
mg/kg body weight, but as little as 0.2 mg/kg body weight may produce toxic symptoms. Skin contact
produces severe and painful burns, with destruction of the underlying tissue. Inhalation of vapors has
produced tracheobronchitis and liver enlargement. There is, however, no evidence that white phosphorus
is carcinogenic in laboratory animals or humans. White phosphorus is a class D carcinogen. Insufficient
evidence exists to determine whether this compound causes cancer in humans, therefore, carcinogenic risks
were not evaluated.
Low concentrations of elemental phosphorus in the water column have been documented as causing acute
effects on aquatic organisms. Fish appear more sensitive to the effects of white phosphorus than
invertebrates. Another concern is the impacts of contamination through the food <•"«"" Rapid
bioaccumulation of white phosphorus has been documented and is related to the lipid content of the
organism. Bioconcentration factors of between 20 and 100 have been reported for aquatic organism tissue.
White phosphorus contamination in various fish tissues has been shown to be toxic or lethal if ingested.
However, due to the reactivity of white phosphorus, the transfer of this element through the food chain
would not be expected In terms of long term food chain contamination, the potential from white
phosphorus is considered nfl.
Toxicity testing was performed on approximately ten percent of the sediment cores from the WPUMBA
area to determine the effects of white phosphorus or other contaminants that might be present on aquatic
life. A freshwater and an estuarine fish species were utilized due to the low salinities found at the
WPUMBA site. It was important to test both types of species, since this site is within the range of the
seasonally moving freshwater/saltwater interface. Marine, estuarine, and freshwater fish are present in
the vicinity during the year. The fathead minnow (Pimephales vromelas) and silverside (Menidiabervllind)
were used in 96 hour acute elutriate tests. The midge (Chironomun tentans). a benthic invertebrate, was
13
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utilized in ten-day acute solid phase tests. The toxitity test results did not clearly indicate any effect of
sediment-bound white phosphorus on aquatic life. It appears, though, that metals present in the sediment
samples may exert some toxic effect on aquatic life and, therefore, monitoring of the water column in the
WPUMBA during dredging activities and after major storm events (hurricane force winds) will be
by the Army.
The absence or low levels of phosphorus detected in WPUMBA sediments, combined with published soil
toxitity results, utilizing worms (chironomids), suggest a low probability of white phosphorus toxitity to
the lower food chain organisms. Bioaccumulation to an upper level consumer, such as waterfowl, has also
been investigated. Avian (bird) toxicity data is minima^ but the lethal dose for phosphorus has been cited
as 3 mg/kg. Several factors, though, suggest that bioaccumulation in waterfowl may be negligible. Migratory
waterfowl use the waters in the APG vicinity during the winter season. Therefore, exposure to the small
quantities of phosphorus detected should be minimal Additionally, waterfowl lipid content during the
winter is elevated. This may serve to isolate any white phosphorus ingested and prevent manifestation of
acute symptoms. Furthermore, large birds rather t-b*» sensitive precotial young would be utilizing the food
resources. For these reasons, sub-lethal effects on waterfowl should be isolated or of a low probability.
Fate and Transport
The processes by which white phosphorus is transformed in air, water, and soil are oxidation, hydrolysis,
and volatilization. White phosphorus is not transformed by photolysis, and it is also resistant to
biodegradation by anaerobic organisms. Although hydrolysis and volatilization *"" have significant effects
on the environmental fate of white phosphorus, its fate in air, soil, and water is generally determined by
oxidative processes. Several investigators observed that the phosphorus oxidation rate hi aqueous systems
can be affected by dissolved oxygen concentration, temperature, pH, salinity, and the presence of metals.
The primary pathway of the degradation of white phosphorus at sediment surfaces is by oxidation, with
the rate dependent upon the available oxygen. White phosphorus in sediment usually will oxidize to the
more stable red allotrope. With the abundance of oxygen at the sediment-water interphase, white
phosphorus will be predominantly oxidized to phosphates roughly within weeks to months. Since several
of these phosphate compounds are possible, fixation of phosphorus probably takes place over a relatively
wide pH range. Also, the large quantities of hydrous iron and aluminum oxides present in most sediments
make possible the fixation of tremendous amounts of phosphorus. However, because most sediments are
anaerobic short distances below the water-sediment boundary surface, phosphorus degradation/oxidation
may be extremely lengthy at such depths. Experiments determined that surface deposits of only a few ppm
of phosphorus oxidize quickly, whereas deeper deposits of higher concentration could remain for years.
Anaerobic sediments can, therefore, serve as sinks for white phosphorus that can, in turn, serve as long-
term sources for mobilization of white phosphorus into the environment if disturbed.
In determining the effect of the phosphorus sedimentation process, the interaction of the phosphorus
species with the sediment present must be understood. It appears that in some sediments, phosphorus is
held in a complex form involving iron as the complexing metal, the stability of which is related to the salt
content of the water. It has been demonstrated in an estuary that the availability of phosphorus from such
sediments decreases with increasing salinity. It has been suggested that salts coagulate the colloidal
particles present, thereby retarding sediment exposure to oxygen. It also appears that the rate and
quantity of phosphorus fixation depends on the type of sediment present. It has been reported that
noncalcerous sediments will absorb and retain more added phosphorus than calcerous lake sediments.
In aquatic systems, phosphorus oxidation can be affected by the concentration above and below the
phosphorus solubility limit (3 mg/1 at 59T). The ability of a sediment to absorb added phosphorus will
decrease with an increase in the water-to-sediment phosphorus concentration. This means that as
phosphorus is added to the water column, the absorbing power of the sediment peaks at a specific range,
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and then decreases, leaving the excess concentration of phosphorus in the aqueous phase. At the same
time, if the water-to-sediment phosphorus concentration continues to increase, the retention capacity of
the sediment will decrease, which would add more phosphorus to the water. In opposition, the percentage
of white phosphorus removed by sediments will increase at lower water-to-sediment phosphorus
concentrations. Its appears that, white phosphorus undergoes oxidation during this partitioning phase, and
that the overall effect of phosphorus binding to sediments depends on water-to-sediment phosphorus
equilibrium.
In applying the above to the WPUMBA, phosphorus tending to remain in the water column would be
indicative of a sediment being oversaturated with phosphorus and releasing it to the aqueous environment.
However, at the WPUMBA no phosphorus was detected in the water column above the supposed burial
area. Additionally, only low concentrations of phosphorus were detected in a few sediment core samples
from the WPUMBA. The environmental release of white phosphorus should cause visible changes in the
aquatic ecosystem. No adverse environmental stress was observed at the WPUMBA. Additionally, white
phosphorus release to the environment would have some abiotic effects as well, such as increased acidity
and decreased dissolved oxygen. Yet, no abnormalities in the abiota were found at the WPUMBA. Thus,
one can assume that the bottom sediments at the WPUMBA are not saturated with phosphorus and at
present are not releasing phosphorus to the aqueous environment. Likewise, the same can be assumed in
the case of groundwater, if the bottom sediments are not saturated with phosphorus, then there is no
reason to suspect phosphorus releases to groundwater.
However, if in the future the waters off APG start to receive an increased amount of phosphorus due
to the accelerating use of fertilizers, the bottom sediments at the WPUMBA could theoretically become
saturated with phosphorus. Also, because of dredging activities that occur in the WPUMBA vicinity, bottom
sediments could be disturbed, causing the release of phosphorus to the environment. With this in mind,
therefore, monitoring of the WPUMBA during dredging activities and following major storm events
(hurricane force winds) will be conducted by the Army.
>
The no effect level for white phosphorus in sediment lies below 2 ug/kg (wet weight). All phosphorus wet
weight concentrations were below 2 ug/kg for the EPAERT investigation. This indicates that the sediment
contains no effect concentrations of white phosphorus. The lack of detectable quantities of phosphorus in
the water column indicates the stability of the white phosphorus in the sediments. The current U.S. EPA
•Quality Criteria for Water" (1086) lists the criteria for total phosphorus as 0.10 ug/1 for marine and
estuarine waters. However, it is possible that undetected white phosphorus could be released to the water
column during disruption of the sediment.
Periodic storms and shifts in winds and waves are the cause for changes in the geomorphometric
processes observed by aerial photographs at the she. An examination of the wind rose at APG indicates
that winds which may cause accretion occur approximately 26% of the time. Winds which may cause
erosion occur approximately 16% of the time. The WPUMBA is sheltered from winds approximately 58%
of the time. Waves of sufficient height and energy are required to cause significant geomorphometric
changes and only occur with high winds. Winds greater than 17 knots in the erosional or accreting
directions only occur about 1% of the time. This indicates that significant erosion or accretion would only
occur during high winds and the occasional severe storm. Therefore, «rignifi>ant sediment disturbance
caused by storms is low.
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SCRIPTION QF TFHg 'NO ACTION*
The EPA ERT investigation of the WPUMBA did not discover any supposed white phosphorus burial area
within the confines of the study location. Based on current site conditions, minimal impacts upon the
aquatic ecosystem are expected. Release of any yet undetected large amounts of white phosphorus is not
expected unless the sediments are disturbed. Likewise, bioassay techniques utilizing fish did not elucidate
any clear toxic effect of white phosphorus on aquatic life. These results lead to a conclusion that any safety
or environmental hazard which may have existed in the past due to the WPUMBA no longer exists. It is
still possible, however, that unexploded ordnance or other safety hazards may exist within the study area.
The goals, therefore, of the selected remedial action are to limit the exposure of the aquatic ecosystem and
human population to any buried material contained in the WPUMBA, and are to be accomplished through
a monitoring/sampling program. Additionally, a future review of the technology available for detecting and
locating the supposed WPUMBA wfll be performed.
Any supposedly buried white phosphorus at the WPUMBA or other sediment-bound material could be
released to the environment if the sediment is disturbed. The Army will, therefore, conduct sampling of
the water column, prior to and during any dredging activities in the area and following major storm events
(hurricane force winds), to monitor and minimize releases of sediment-bound materials to the environment.
Water samples will be analyzed for phosphorus, using a detection limit of 0.01 ppb which is 10% of the
established aquatic toxicity concentration, and metals utilizing approved EPA quantitation detection limits.
A five year review wQl be performed to identify possible technological advances that might be developed
which have a greater detection/location capability for buried white phosphorus then currently exists today.
All activities at the WPUMBA will be conducted in compliance with Federal and State law including:
- Rivers and Harbors Act of 1899, Section 10
• Clean Water Act of 1972, as amended (33 USC 466),
emphasizing Sections 115, 313(a), and 404
• Fish & Wildlife Coordination Act of 1958 (16 USC 661 et. seq.)
• Fish & Wildlife Conservation Act of 1980
- Endangered Species Act of 1973, as amended (16 USC 1531)
- Migratory Bird Act of 1918
- Migratory Bird Treaty Act of 19. 72 (16 USC 703-711)
- Coastal Zone Management Act of 1972 (16 USC 1451), Sec. 307 c3
- National Environmental Policy Act of 1969 (42 USC 4321 et seq)
- Executive Order 11990
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