This document is part of Appendix A, and includes the Surface Vessel 

Bilgewater/Oil Water Separator: Nature of Discharge for the “Phase I Final Rule 

and Technical Development Document of Uniform National Discharge Standards 

(UNDS),” published in April 1999. The reference number is EPA-842-R-99-001. 

Phase I Final Rule and Technical Development 

Document of Uniform National Discharge 

Standards (UNDS)

Surface Vessel Bilgewater/Oil Water Separator: 

Nature of Discharge

April 1999 
NATURE OF DISCHARGE REPORT

Surface Vessel Bilgewater/Oil Water Separator (OWS) Discharge 

1.0 INTRODUCTION 

The National Defense Authorization Act of 1996 amended Section 312 of the Federal 

Water Pollution Control Act (also known as the Clean Water Act (CWA)) to require that the 

Secretary of Defense and the Administrator of the Environmental Protection Agency (EPA) 

develop uniform national discharge standards (UNDS) for vessels of the armed forces for 

“...discharges, other than sewage, incidental to normal operation of a vessel of the Armed Forces, 

...” [Section 312(n)(1)]. UNDS is being developed in three phases. The first phase (which this 

report supports), will determine which discharges will be required to be controlled by marine 

pollution control devices (MPCDs)—either equipment or management practices. The second 

phase will develop MPCD performance standards. The final phase will determine the design, 

construction, installation, and use of MPCDs. 

A nature of discharge (NOD) report has been prepared for each of the discharges that 

have been identified as candidates for regulation under UNDS. The NOD reports were 

developed based on information obtained from the technical community within the Navy and 

other branches of the armed services with vessels potentially subject to UNDS, from information 

available in existing technical reports and documentation, and, when required, from data 

obtained from discharge samples that were collected under the UNDS program. 

The purpose of the NOD report is to describe the discharge in detail, including the system 

that produces the discharge, the equipment involved, the constituents released to the 

environment, and the current practice, if any, to prevent or minimize environmental effects. 

Where existing process information is insufficient to characterize the discharge, the NOD report 

provides the results of additional sampling or other data gathered on the discharge. Based on 

above information, the NOD report describes how the estimated constituent concentrations and 

mass loading to the environment were determined. Finally, the NOD report assesses the 

potential for environmental effect. The NOD report contain sections on: Discharge Description, 

Discharge Characteristics, Nature of Discharge Analysis, Conclusions, and Data Sources and 

References. 

Surface Vessel Bilgewater/Oil Water Separator (OWS) Discharge 

1 
2.0 DISCHARGE DESCRIPTION 

This section describes the bilgewater/OWS discharge and includes information on: the 

equipment that is used and its operation (Section 2.1), general description of the constituents of 

the discharge (Section 2.2), and the vessels that produce this discharge (Section 2.3). 

2.1 Equipment Description and Operation 

2.1.1 The Bilge Area 

The lowest inner part of the hull where liquid drains from the interior spaces and the 

upper decks of the vessel is referred to as the bilge. The primary sources of drainage into the 

bilge are the main engine room(s) and the auxiliary machinery room(s), which house the vessel’s 

propulsion system and auxiliary systems (i.e., steam boilers and water purification systems), 

respectively. Other spaces that collect and contain fluid drainage in their bilge are the shaft alley, 

steering gear rooms, pump rooms, and air conditioning and refrigeration machinery rooms. 

Some oil lab sink drains are also directed to the bilge. The liquid collected in the bilge is known 

as “bilgewater” or “oily wastewater”. 

2.1.2 Composition of Bilgewater 

The composition of bilgewater varies from vessel to vessel; the composition of bilgewater 

also varies from day to day on the same vessel. Certain wastestreams, including steam 

condensate, boiler blowdown, drinking fountain water, and sink drainage located in various 

machinery spaces, can drain to the bilge. The propulsion system and auxiliary systems use fuels, 

lubricants, hydraulic fluid, antifreeze, solvents, and cleaning chemicals, as part of routine 

operation and maintenance. Small quantities of these materials enter the bilge as leaks and spills 

in the engineering spaces. On some older vessels, excess potable water produced by onboard 

water purification systems is directed to the bilge, although this practice is being phased out.1

 On 

some Navy and Coast Guard vessels, water from gas turbine washdowns can contribute to 

bilgewater generation; these washdowns are described in the Gas Turbine Water Wash NOD 

report. 

2.1.3 Bilgewater Treatment and Transfer System 

Every surface vessel has an onboard system for collecting and transferring bilgewater. 

Vessels pump collected bilgewater to a holding tank which the Navy refers to as the oily waste 

holding tank (OWHT). Some vessels are capable of transferring bilgewater from the OWHT to 

shore facilities while pierside. OWS systems are installed on vessels, as appropriate, to reduce 

the oil content of bilgewater prior to overboard discharge. These systems receive bilgewater 

from the OWHT and use gravity-phase separation, coalescence, centrifugal separation, or 

combinations of these technologies to treat the waste. 

A commonly used Navy OWS is a coalescing plate gravity separator. This type of 

separator has a horizontal set of oleophilic plates. Oil droplets rise and coalesce as they flow 

Surface Vessel Bilgewater/Oil Water Separator (OWS) Discharge 

2 
through the plates. The droplets cling to and wet the oleophilic plates once they rise to a plate’s 

underside. When sufficient oil has accumulated, large oil droplets rise through weep holes in the 

plates and flow to the top of the OWS. The separated oil is then transferred to a waste oil tank 

(WOT). Figure 1 is a process flow diagram of the standard OWS system used on most Navy 

vessels. 

On some vessels, oil content monitors (OCMs) are installed to prevent the discharge of 

unacceptable effluent. If the oil content is above the set point limit, the OCM alarms and diverts 

the OWS effluent back to the OWHT for reprocessing until an acceptable oil concentration 

reading is obtained. 

In addition to the oil removed by the OWS, waste oil from routine maintenance is also 

collected in the WOT and held for pierside disposal. 

Synthetic lubricant oils (SLOs) are not collected in the WOT, and measures are taken to 

prevent their introduction into the bilge. SLOs have a specific gravity close to that of water and 

cannot be separated in the OWS. These oils are normally found in engine spaces and are 

collected in drip pans located underneath the engines. The drip pans drain through segregated 

piping to dedicated collection tanks. SLOs within these tanks are disposed of on-shore separately 

from non-synthetic waste oils. Therefore, SLOs, except for tank overflows, are not likely to be in 

bilgewater at significant levels. 

Some ships (e.g., DDG 51 Class destroyers) use non-oily machinery wastewater 

collection systems that segregate oily wastewater from non-oily wastewater. These ships collect 

non-oily machinery wastewater in dedicated collection tanks instead of the bilge, and discharge it 

directly overboard. All oily wastewater collects in OWHTs and is processed by a shipboard 

OWS or off-loaded for shore facility treatment. 

2.2 Releases to the Environment 

Untreated bilgewater is expected to contain oil and grease (O&G), an assortment of 

oxygen-demanding substances, and organic and inorganic materials. These materials include 

volatile organic compounds (VOCs), semi-volatile organic, inorganic salts, and metals. OWS 

effluent releases to the environment contain the same constituents present in bilgewater but with 

lower concentrations of O&G and oil-soluble components. 

2.3 Vessels Producing the Discharge 

All vessels produce bilgewater. OWS systems have been installed on most vessels of the 

Armed Forces. Some small boats and craft are not outfitted with OWS systems; thus, bilgewater 

is stored for shore disposal. Table 1 lists all surface vessels equipped with OWSs. Submarine 

bilgewater is addressed in the Submarine Bilgewater NOD report. 

3.0 DISCHARGE CHARACTERISTICS 

Surface Vessel Bilgewater/Oil Water Separator (OWS) Discharge 

3 
This section contains qualitative and quantitative information which characterizes the 

discharge. Section 3.1 describes where the discharge occurs with respect to harbors and nearshore areas, Section 3.2 describes the rate of the discharge, Section 3.3 lists the constituents in 

the discharge, and Section 3.4 gives the concentrations of the constituents in the discharge. 

3.1 Locality 

The Armed Forces do not discharge untreated bilgewater to surface waters. On ships 

without OWS systems, untreated bilgewater is held for transfer to a shore treatment facility. 

Bilgewater treated by an OWS can be discharged within or beyond 12 nautical miles (n.m.). On 

Navy vessels with an OWS and OCM, oil concentrations must be less than 15 parts per million 

(ppm) prior to discharge. However aboard Navy vessels, discharge of bilgewater with an oil 

concentration less than 100 ppm is allowed outside 12 n.m. if concentrations less than 15 ppm 

cannot be achieved because of operating conditions. 

3.2 Rate 

Bilgewater generation rates vary by vessel and vessel class because of the differences in 

vessel age, shipboard equipment (e.g., type of propulsion system), operations, and procedures. 

Vessels with non-oily machinery wastewater collection systems will generate significantly less 

bilgewater because of their capability to keep non-oily waste streams out of the bilges. The DDG 

51 and CVN 68 class ships are two examples of ship classes that have non-oily machinery 

wastewater collection systems. Other factors influencing bilgewater generation rates are whether 

a vessel is operating in-port or at-sea, and when in port, whether it is operating in an auxiliary 

steaming mode or receiving shore electrical/steam power (cold iron mode). In the auxiliary 

steaming mode, a vessel provides its own services while moored at the pier (i.e., power, 

freshwater, etc.). In the cold iron mode, a vessel receives these services from shore facilities, 

minimizing the amount of shipboard equipment in operation. Older vessels without non-oily 

machinery wastewater collection systems have historically generated more bilgewater while 

operating in the auxiliary steaming mode than in the cold iron mode because of the discharge of 

utilities wastewater to the bilge. 

Table 2 shows the in-port bilgewater generation rates for certain destroyers (DD 963 and 

DDG 51 Classes) and aircraft carriers (CVN 68 Class). For the destroyers, bilgewater generation 

rates were developed by monitoring the levels of bilgewater in the bilges.1,2 Aircraft carrier class 

(CVN 68) data was gathered from an analysis of a carrier’s (CVN 74) OWS operator log sheets 

in order to determine the amount of bilgewater that had passed through the OWS over an 

extended period of time, thus providing an estimate of the bilgewater generation rate.3 

Table 3 summarizes the bilgewater/OWS flow rates that were developed for an aircraft 

carrier class (CVN 68), “other ship classes,” and the overall fleet based on the average values 

from Table 2. The assumptions that were made in developing the estimates are summarized as 

follows: 

Surface Vessel Bilgewater/Oil Water Separator (OWS) Discharge 

4 
1. The average and maximum daily bilgewater OWS discharge flow rates for a carrier 

(CVN 74) of 3,000 and 25,000 gallons per day (gpd), respectively, represents the 

average and maximum daily bilgewater/OWS flow for all aircraft carriers. 

2. The destroyer (DD 963) bilgewater flow estimate of 1,000 to 3,000 gpd represents a 

typical range of flows for other U.S. Navy surface ship classes. An average of 2,000 

gpd is assumed to be the average bilgewater generation rate. 

3. Aircraft carriers spend approximately 147 days in port annually. 

4. Other ships are in port for approximately 193 days annually. 

The calculations used to estimate the total fleet bilgewater OWS effluent discharge to 

surface waters within 12 n.m. are presented as follows: 

CVN 68 Class 

FCVN(flow rate) = (RCVN)(DCVN NCVN) 

RCVN = ship flow rate, gpd 

DCVN = days in port annually per ship 

NCVN = number of ships 

FCVN = (3,000) (147) (11) = 4.9 million gallons per year 

) (

Other Ship Classes 

FO(flow rate) = (RO DO NO) 

FO = (2,000) (193) (220) = 84.9 million gallons per year 

) ( ) (

Overall Fleet 

FFLEET = FCVN (million gals/year) + FO (million gals/year) 

FFLEET = 4.9 + 84.9 = 89.8 million gallons per year 

It should be noted that bilgewater generation rates are based on data available from 

existing reports for U.S. Navy ships and does not include “estimates of bilgewater” from ships of 

other services. 

3.3 Constituents 

Information about the constituents of bilgewater comes from several studies conducted 

aboard Navy vessels and at Navy ports, in addition to the UNDS Phase I testing. During these 

Surface Vessel Bilgewater/Oil Water Separator (OWS) Discharge 

5 
previous studies, samples of bilgewater were collected from a variety of Navy vessels, including 

aircraft carriers, cruisers, destroyers, dock landing ships, tank landing ships, amphibious assault 

ships, amphibious transport docks, and submarines. There have been no similar studies or 

documentation available for the other services. 

Bilgewater samples collected in the previous studies were analyzed for a variety of 

parameters, such as classicals, metals, and organics (including pesticides). Over 25 priority 

pollutants were identified from these samples, including metals such as arsenic, copper, 

cadmium, chromium, lead, mercury, selenium, and zinc; and organics such as benzene, the BHC 

isomers (isomers of hexachlorocyclohexane), ethyl benzene, heptachlor, heptachlor epoxide, 

naphthalene, phenols, phthalate esters, toluene, trichlorobenzene, and trichloroethane. The 

bioaccumulators identified in these samples were the BHC isomers and mercury. A variety of 

substances that are neither priority pollutants nor bioaccumulators were also detected, including 

metals such as barium and manganese and organics such as chloroform and xylene. 

The analytical results from these studies are shown in Tables 4 through 8. The results 

provide a general overview of the constituents that have historically been detected in bilgewater 

and the effluent from bilgewater OWS treatment. 

3.4 Concentrations 

The concentrations of constituents detected during UNDS Phase I testing of 

bilgewater/OWS effluent samples collected aboard an aircraft carrier (CVN 74) are summarized 

in Table 9. Many of the same constituents that were detected in the previous studies were also 

detected in the aircraft carrier samples. This includes classicals, oil & grease as indicated by 

hexane extractable materials (HEM) or total petroleum hydrocarbons (TPH) as indicated by silica 

gel treated hexane extractable materials (SGT-HEM), certain metals, and the bioaccumulator, 

mercury. Neither pesticides nor PCBs were detected in the aircraft carrier bilgewater/OWS 

samples. Table 10 presents the general statistics of the aircraft carrier data. 

Analytical results from previous bilgewater studies are shown in Tables 4 through 8. 

These tables provide concentrations of constituents that have historically been detected in 

bilgewater and the effluent from bilgewater OWS treatment. 

4.0 NATURE OF DISCHARGE ANALYSIS 

Based on the discharge characteristics presented in Section 3.0, the nature of the 

discharge and its potential impact on the environment can be evaluated. Estimated constituent 

mass loadings are presented in Section 4.1. In Section 4.2, the available concentration data for 

the discharge constituents are evaluated, including comparison with federal and state water 

quality criteria. In Section 4.3, the potential for the transfer of non-indigenous species is 

discussed. 

4.1 Mass Loading 

Surface Vessel Bilgewater/Oil Water Separator (OWS) Discharge 

6 
Validated bilgewater/OWS constituent concentration data from the aircraft carrier 4

 and 

the flow rate estimates referenced in NOD report Section 3.2 were used to estimate the mass 

loading of pollutants to the environment. Historical data were not used to estimate mass loadings 

because these data were not validated. 

Table 11 provides a bilgewater/OWS effluent mass loading summary for all constituents 

detected in the aircraft carrier samples. Sampling data have identified copper, nickel, and zinc as 

exceeding Federal water quality criteria (in addition to the most stringent state criteria) in the 

bilgewater/OWS samples analyzed. Also, the concentrations for ammonia, nitrogen (as 

nitrate/nitrite and total kjeldahl nitrogen), phosphorous, iron, and total petroleum hydrocarbons 

exceeds the most stringent state water quality criteria. 

The constituent loading estimates are based on the assumption that vessels with an onboard OWS system will always process bilgewater through the system and discharge the effluent 

overboard while in-port, rather than off-loading untreated bilgewater to shore facilities for 

disposal. 

Sample calculations for TPH, as indicated by SGT-HEM, are provided to show how the 

total fleet constituent discharges to surface waters less than 12 n.m. from shore were calculated. 

The assumptions and calculations are presented below. 

1. The total amount of OWS effluent discharged annually from aircraft carriers is 4.9 million 

gallons (Table 3). 

2. The sample data from CVN 74 (Table 10) are assumed to be representative of all aircraft 

carriers. 

M(tph)CVN (pounds/year) = (VCVN (million gals/year)) (CCVN (mg/Liter)) (CF) 

where: VCVN = Total bilgewater/OWS generation rate/year 

CCVN = TPH (SGT-HEM) concentration

 CF = conversion factor = 8.34 = (3.785 liters/gal) (1x106 gals/million gals)

 (454 grams/pound) (1,000 mg/gram) 

MCVN = (4.9) (9.64) (8.34) = 394 pounds/year 

The mass loading of constituents for the entire fleet can be estimated by multiplying the estimate 

for aircraft carriers by a discharge ratio. The discharge ratio is the total fleet discharge rate 

divided by the total discharge from aircraft carriers. Use of this ratio to estimate fleet mass 

loadings assumes sample data from CVN 74 (Table 10) is representative of all vessels of the 

armed forces. 

Surface Vessel Bilgewater/Oil Water Separator (OWS) Discharge 

7 
2. Ratioing the total flow for the fleet (89.8 mgd) to the aircraft carrier class (CVN 68) flow for 

(4.9 mgd) , and multiplying the aircraft carrier loading by the ratio.

MFLEET = (FFLEET / Fcvn ) (MCVN) 

MFLEET = (89.8/4.9)(394)=7220 pounds/year 

4.2 Environmental Concentrations 

Table 11 identifies bilgewater OWS effluent constituents in the aircraft carrier samples 

whose log mean average concentrations (dissolved and/or total) were above Federal water quality 

criteria, and/or the most stringent state water quality criteria. With regard to oil concentration 

data, the samples were analyzed for HEM and SGT-HEM. The HEM values correspond to oil 

and grease and the SGT-HEM values correspond to total petroleum hydrocarbon (TPH) which is 

a subset of oil and grease. 

4.3 Potential for Introducing Non-indigenous Species 

There is a low potential for transporting non-indigenous species in this discharge. There 

is only minor seawater access to bilge compartments, and bilgewater is generally processed 

before it is transported over long distances. 

5.0 CONCLUSIONS 

Surface vessel bilgewater and OWS discharges have the potential to cause an adverse 

environmental effect for the following reasons: 

1) Bilgewater, if discharged without treatment, would contribute significant amounts of oil to the 

environment at concentrations exceeding water quality criteria and discharge standards. 

2) OWS effluent contributes significant amounts of oil to the environment at concentrations 

exceeding water quality criteria and discharge standards. 

6.0 DATA SOURCES AND REFERENCES 

To characterize this discharge, information from various sources was obtained. Process 

information and assumptions were used to estimate the rate of discharge. Based on this estimate 

and on the reported concentrations of oil and grease constituents, the concentrations of the oil 

and grease constituents in the environment resulting from this discharge were then estimated. 

Surface Vessel Bilgewater/Oil Water Separator (OWS) Discharge 

8 
Table 12 shows the source of the data used to develop this NOD Report. 

1. Bilgewater Characterization and Generation Surveys Aboard DD-963 Class Ships. April, 

1981. David Taylor Naval Ship Research and Development Center. Report #: 

DTNSRDC/SME-81/09. 

2. In-Port Oily Wastewater Generation on USS ARLEIGH BURKE (DDG 51), NSWCCD-TR63-96/37. November 1996. 

3. USS John C. Stennis (CVN 74) OWS log sheets obtained from CVN 74 by J. Jereb of DLS 

Engineering Assoc. and submitted to Malcolm-Pirnie via facsimile on February 13, 1997. 

4. Correspondence from Commander, Naval Surface Warfare Center, Carderock Division, 

Philadelphia Site to Commander, Naval Sea Systems Command (Code 03L13), Uniform 

National Discharge Standards (UNDS) Sampling Program Data, Ser 631/225, 1-6310-280, 

dated June 19, 1997. 

5. The Characterization of Bilgewater Aboard U.S. Navy Ships. October 1992. Naval Surface 

Warfare Center Carderock Division. Tech. Report #: CDNSWC/SME-CR-10-91. 

6. Weaver, George, An Analysis of Bilgewater. Undated, Analytical data for period from 1993 

to 1995. Navy Public Works Center Environmental Department, Naval Station San Diego. 

7. Wastewater Characterization Data from USS L Y Spear (AS 36) and USS Carney (DDG 64), 

NSWCCD, 6330-270/KA, February 19, 1997, Enclosures (4) and (6). 

General References 

USEPA. Toxics Criteria for Those States Not Complying with Clean Water Act Section 

303(c)(2)(B). 40 CFR Part 131.36. 

USEPA. Interim Final Rule. Water Quality Standards; Establishment of Numeric Criteria for 

Priority Toxic Pollutants; States’ Compliance – Revision of Metals Criteria. 60 FR 

22230. May 4, 1995. 

USEPA. Water Quality Standards; Establishment of Numeric Criteria for Priority Toxic 

Pollutants. 57 FR 60848. December 22, 1992. 

USEPA. Water Quality Standards; Establishment of Numeric Criteria for Priority Toxic 

Pollutants for the State of California, Proposed Rule under 40 CFR Part 131, Federal 

Register, Vol. 62, Number 150. August 5, 1997. 

Connecticut. Department of Environmental Protection. Water Quality Standards. Surface Water 

Quality Standards Effective April 8, 1997. 

Surface Vessel Bilgewater/Oil Water Separator (OWS) Discharge 

9 
Florida. Department of Environmental Protection. Surface Water Quality Standards, Chapter 

62-302. Effective December 26, 1996. 

Georgia Final Regulations. Chapter 391-3-6, Water Quality Control, as provided by The Bureau 

of National Affairs, Inc., 1996. 

Hawaii. Hawaiian Water Quality Standards. Section 11, Chapter 54 of the State Code. 

Mississippi. Water Quality Criteria for Intrastate, Interstate and Coastal Waters. Mississippi 

Department of Environmental Quality, Office of Pollution Control. Adopted November 

16, 1995. 

New Jersey Final Regulations. Surface Water Quality Standards, Section 7:9B-1, as provided by 

The Bureau of National Affairs, Inc., 1996. 

Texas. Texas Surface Water Quality Standards, Sections 307.2 - 307.10. Texas Natural 

Resource Conservation Commission. Effective July 13, 1995. 

Virginia. Water Quality Standards. Chapter 260, Virginia Administrative Code (VAC) , 9 VAC 

25-260. 

Washington. Water Quality Standards for Surface Waters of the State of Washington. Chapter 

173-201A, Washington Administrative Code (WAC). 

Navy Small Craft Bilge Generation and Characterization. March, 1987. David W. Taylor Naval 

Ship Research and Development Center, Report No. DTNSRDC/SME-86/32. 

Personal Communication between C. Geiling, Malcolm-Pirnie, and Brian Gordon, NAVSTA San 

Diego, Week of February 17, 1997, Topic of discussion: bilgewater characterization. 

Environmental and Natural Resources Program Manual, OPNAVINST 5090.1B, Department of 

the Navy, November 1, 1994. 

Department of Defense (DoD) Directive 6050.15 of 14 June 1985, Prevention of Oil Pollution 

from Ships Owned or Operated by the DoD (NOTAL). 

Committee Print Number 95-30 of the Committee on Public Works and Transportation of the 

House of Representatives, Table 1. 

The Water Quality Guidance for the Great Lakes System, Table 6A. Volume 60 Federal 

Register, p. 15366. March 23, 1995. 

UNDS Equipment Expert Meeting Minutes. “Surface Vessel Bilgewater and Oily Waste”. July 

29, 1996. 

Surface Vessel Bilgewater/Oil Water Separator (OWS) Discharge 

10 
Pentagon Ship Movement Data for Years 1991-95, March 4, 1997. 

UNDS Phase I Sampling Data Report, Volumes 1-13, October 1997. 

UNDS Ship Database, August 1, 1997. 

Surface Vessel Bilgewater/Oil Water Separator (OWS) Discharge 

11 
Figure 1. U.S. Navy Oil Water Separator (OWS) Process Flow Diagram (Typical) 

Surface Vessel Bilgewater/Oil Water Separator (OWS) Discharge 

12 
Table 1. Vessels Equipped With Oil/Water Separator Systems 

SHIP CLASSIFICATION INFORMATION TRANSIT 

INFORMATION 

CLASS 

ID NO. 

ARMED 

SERVICE 

CLASS 

NAME SHIP TYPE 

NO. OF 

SHIPS 

PROPULSION 

SYSTEM 

TRAN­ DAYS IN 

SITS PORT 

AE 26 MSC Kilauea Ammunition Ship 8 Steam 4 26 

AFS 1 MSC Mars Combat Store Ship (ROS) 8 Steam 7 148 

AG 194 MSC Vanguard Navigation Research Ship 2 Steam 10 151 

AGF 3 NAVY Austin (Converted) Miscellaneous Command Ship 1 Steam NA NA 

AGF 11 NAVY Austin (Converted) Miscellaneous Command Ship 1 Steam NA NA 

AGM 22 MSC Converted Haskell Missile Range Instrumentation Ship 1 Steam 4 133 

AGOS 1 MSC Stalwart Ocean Surveillance Ship 5 Diesel 4 70 

AGOS 19 MSC Victorious Ocean Surveillance Ship 4 Diesel 5 107 

AGS 26 MSC Silas Bent and Wilkes Surveying Ship 2 Diesel 6 44 

AGS 45 MSC Waters Surveying Ship 1 Diesel 1 7 

AGS 51 MSC John McDonnell Surveying Ship 2 Diesel 6 96 

AGS 60 MSC Pathfinder Surveying Ship 4 Diesel NA NA 

AH 19 MSC Mercy Hospital Ship (ROS) 2 Steam 2 184 

AKR 287 MSC Algol Vehicle Cargo Ship (ROS) 8 Steam 3 109 

AKR 295 MSC NA Vehicle Cargo Ship (ROS) 3 Diesel NA NA 

AO 177 NAVY Jumboised Cimarron Oiler 5 Steam 10 188 

AO 187 MSC Henry J. Kaiser Oiler 12 Diesel 6 78 

AOE 1 NAVY Sacramento Fast Combat Support Ship 4 Steam 11 183 

AOE 6 NAVY Supply Fast Combat Support Ship 3 Gas 6 114 

AR NAVY Vulcan Repair Ship 6 Steam 8 131 

ARC 7 MSC Zeus Cable Ship 1 Diesel 2 8 

ARS 50 NAVY Safeguard Salvage Ships 4 Diesel 22 208 

AS 33 NAVY Simon Lake Submarine Tender 1 Steam 6 229 

AS 39 NAVY Emory S Land Submarine Tender 3 Steam 6 293 

ATF 166 MSC Powhatan Fleet Ocean Tug 7 Diesel 16 127 

BD ARMY 264B Barge Derrick(Floating Cranes) 12 Diesel NA NA 

BO USCG NA Buoy Boat 5 Diesel NA NA 

BOSL USCG NA Stern Loading Buoy Boat 14 Diesel NA NA 

CG 47 NAVY Ticonderoga Guided Missile Cruiser 27 Gas 12 166 

CGN 36 NAVY California Guided Missile Cruiser 2 Nuclear 11 143 

CGN 38 NAVY Virginia Guided Missile Cruiser 1 Nuclear 11 161 

CV 63 NAVY Kitty Hawk Aircraft Carrier 3 Steam 7 137 

CVN 65 NAVY Enterprise Aircraft Carrier 1 Nuclear 6 76 

CVN 68 NAVY Nimitz Aircraft Carrier 7 Nuclear 7 147 

DD 963 NAVY Spruance Destroyer (Typical) 31 Gas 12 178 

DDG 51 NAVY Arleigh Burke Guided Missile Destroyer 18 Gas 11 101 

DDG 993 NAVY Kidd Guided Missile Destroyer 4 Gas 12 175 

FFG 7 NAVY Oliver Hazard Perry Guided Missile Frigate 43 Gas 13 167 

LCC 19 NAVY Blue Ridge Amphibious Command Ship 2 Steam 8 179 

LCU ARMY 2000 Utility Landing Craft 48 Diesel NA NA 

LHA 1 NAVY Tarawa Amphibious Assault Ship 5 Steam 9 173 

LHD 1 NAVY Wasp Amphibious Assault Ship 4 Steam 13 185 

Surface Vessel Bilgewater/Oil Water Separator (OWS) Discharge 

13 
Table 1. Vessels Equipped With Oil/Water Separator Systems (cont'd) 

SHIP CLASSIFICATION INFORMATION TRANSIT 

INFORMATION 

CLASS 

ID NO. 

ARMED 

SERVICE 

CLASS 

NAME SHIP TYPE 

NO. OF 

SHIPS 

PROPULSION 

SYSTEM 

TRAN­ DAYS IN 

SITS PORT 

LPD 4 NAVY Austin Amphibious Transport Dock 3 Steam 11 178 

LPD 7 NAVY Austin Amphibious Transport Dock 3 Steam 12 188 

LPD 14 NAVY Austin Amphibious Transport Dock 2 Steam 11 192 

LPH 2 NAVY Iwo Jima Amphibious Assault Helicopter 

Carrier 

2 Steam 11 186 

LSD 36 NAVY Anchorage Dock Landing Ship 5 Steam 13 215 

LSD 41 NAVY Whidbey Island Dock Landing Ship 8 Diesel 13 170 

LSD 49 NAVY Harpers Ferry Dock Landing Ship 3 Diesel NA NA 

LST 1179 NAVY Newport Tank Landing Ship 3 Diesel 13 191 

LSV ARMY Frank S Besson Vehicle Landing Ship 6 Diesel NA NA 

LT ARMY 100 / 130 Large Tug 25 Diesel NA NA 

MCM 1 NAVY Avenger Mine Countermeasure Vessel 14 Diesel 28 232 

MHC 51 NAVY Osprey Minehunters Coastal 12 Diesel NA NA 

WAGB 290 USCG Mackinaw Icebreaker 1 Diesel NA NA 

WAGB 399 USCG Polar Icebreaker 2 Diesel 4 139 

WHEC 378 USCG Hamilton/Hero Class High Endurance Cutter 12 Diesel 13 151 

WIX 295 USCG Eagle Sail Training Cutter 1 Diesel 7 188 

WLB 180A USCG Balsam Seagoing Tender 8 Diesel 18 190 

WLB 180B USCG Balsam Seagoing Tender 2 Diesel 5 120 

WLB 180C USCG Balsam Seagoing Tender 13 Diesel 16 123 

WLB 225 USCG Juniper Seagoing Tender 2 Diesel NA NA 

WLI 65303 USCG Blackberry Buoy Tender, Inland 2 Diesel NA NA 

WLI 65400 USCG Bayberry Buoy Tender, Inland 2 Diesel NA NA 

WLI 100A USCG Blue Bell Buoy Tender, Inland 1 Diesel NA NA 

WLI 100C USCG Blue Bell Buoy Tender, Inland 1 Diesel NA NA 

WLIC 75A USCG Anvil/Clamp Construction Tenders, Inland 2 Diesel NA NA 

WLIC 75B USCG Anvil/Clamp Construction Tenders, Inland 3 Diesel NA NA 

WLIC 75D USCG Anvil/Clamp Construction Tenders, Inland 2 Diesel NA NA 

WLIC 100 USCG Cosmos Construction Tenders, Inland 3 Diesel NA NA 

WLIC 115 USCG ? Construction Tenders, Inland 1 Diesel NA NA 

WLIC 160 USCG Pamlico Construction Tenders, Inland 4 Diesel NA NA 

WLM 157 USCG Red Buoy Tender, Coastal 9 Diesel NA NA 

WLM 551 USCG Keeper Buoy Tender, Coastal 2 Diesel NA NA 

WLR 65 USCG Ouachita Buoy Tender, River 6 Diesel NA NA 

WLR 75 USCG F/Gasconade Buoy Tender, River 13 Diesel NA NA 

WLR 115 USCG Sumac Buoy Tender, River 1 Diesel NA NA 

WMEC 210A USCG Reliance Medium Endurance Class 5 Diesel 13 235 

WMEC 210B USCG Reliance Medium Endurance Class 11 Diesel 9 149 

Surface Vessel Bilgewater/Oil Water Separator (OWS) Discharge 

14 
Table 1. Vessels Equipped With Oil/Water Separator Systems (cont'd) 

SHIP CLASSIFICATION INFORMATION TRANSIT 

INFORMATION 

CLASS ARMED CLASS NO. OF PROPULSION TRAN­ DAYS IN 

ID NO. SERVICE NAME SHIP TYPE SHIPS SYSTEM SITS PORT 

WMEC 213 USCG Diver Medium Endurance Class 1 Diesel 9 98 

WMEC 230 USCG Storis Medium Endurance Class 1 Diesel 11 167 

WMEC 270A USCG Bear Medium Endurance Class 4 Diesel 6 137 

WMEC 270B USCG Bear Medium Endurance Class 9 Diesel 7 164 

WPB 82C USCG Point Patrol Craft 28 Diesel NA NA 

WPB 82D USCG Point Patrol Craft 8 Diesel NA NA 

WPB 110A USCG Island Patrol Craft 16 Diesel 2 72 

WPB 110B USCG Island Patrol Craft 21 Diesel 7 137 

WPB 110C USCG Island Patrol Craft 12 Diesel 5 157 

WTGB 140 USCG Bay Icebreaking Tug 9 Diesel 1 8 

WYTL 65A USCG NA Harbor Tug 3 Diesel NA NA 

WYTL 65B USCG NA Harbor Tug 3 Diesel NA NA 

WYTL 65C USCG NA Harbor Tug 3 Diesel NA NA 

WYTL 65D USCG NA Harbor Tug 2 Diesel NA NA 

TOTAL: 640 AVG: 9 145 

Subtotals: 

Navy 231 13 197 

MSC 70 5 92 

USCG 248 8 140 

Army 91 NA NA 

Notes: 

1. NA = Information not available 

2. One transit = travel from one port to another, or from one port to sea and returning back to same port. 

Surface Vessel Bilgewater/Oil Water Separator (OWS) Discharge 

15 
Table 2. In-Port Bilgewater Generation Rates1,2,3 

Ship Class Gal/Day (Range) Avg Gal/Day 

DD 963 1,000-3,000 2,000 

DDG 51 N/A 335 

CVN 68* 5,000-25,000 3,000 

* Values based on recording information over a 30 day period. All bilgewater was processed by 

the OWS during six individual days, in volumes ranging from 5,000 to 25,000 gallons per 

processing event. The total volume processed over 30 days was 91,000 gallons, yielding an 

average daily processing rate of 3,000 gallons per day. 

Table 3. In-Port Bilgewater/OWS Discharge Rates From U.S. Navy Ships 

Ship Class 

Average Daily Flow 

per Ship (gals/day) 

Annual Flow per Ship

 (gals/yr) 

Total Annual Flow 

(million gals/yr) 

Days in 

Port 

Total 

Flow 

No. of 

Ships 

Total 

Flow 

Aircraft Carriers 3,000 147 441,000 11 4.9 

All Other Ships (Avg.) 2,000 178 356,000 220 84.9 

Total: 89.8 

Surface Vessel Bilgewater/Oil Water Separator (OWS) Discharge 

16 
Table 4. Ship Study Bilgewater Pollutant Summary5 

Biddle 

CG 34 

Vincennes 

CG 49

 with OWS 

San Jacinto 

CG 56

 with OWS 

Roosevelt 

CVN 71 

C. DeGrasse 

DD 974 

H.W. Hill 

DD 986 

Belleau 

Wood 

LHA 3 

Vancouver 

LPD 2

 with OWS 

Pensacola 

LSD 38

 with OWS 

Manitowoc 

LST 1180

 with OWS 

Louisville 

SSN 724 

TSS (mg/L) 1,440 38 19 519 233 548 1205 62 29 114 169 

COD (mg/L) 5,600 530 760 5,400 18,000 11,000 66,000 780 470 1,600 1,100 

TOC (mg/L) 644 129 34.6 116 264 4,620 19,040 34 31 224 247 

BOD (mg/L) 583 NA 6,740 554 >14,000 842 13,000 <142 98 335 0 

O&G (mg/L) 46 27 8 1,550 725 765 5,220 20 4 32 164 

Phenols(mg/L) 600 110 30 <5,000 <10 40 2,600 10 10 20 310 

Cu (mg/L) 6,400 540 430 1,050 5,320 1,180 1,720 790 300 360 1,450 

Fe (mg/L) 46,000 810 260 2,560 28,000 18,900 14,600 1,130 1,620 2,600 1,030 

Zn (mg/L) 4,300 810 190 1,900 6,560 1,390 16,200 1,590 410 2.5 2,720 

Cd (mg/L) 67 10 5 21 156 44 280 <3 <5 14 82 

Ag (mg/L) 10 <10 10 <50 <10 <10 80 10 <10 <10 <10 

Ni (mg/L) 3,500 270 130 170 890 550 650 400 210 120 1,590 

Mn (mg/L) 3,000 220 20 140 1,350 1,150 370 61 110 210 269 

Pb (mg/L) 230 20 <20 <30 2,900 30 270 20 50 <50 60 

As (mg/L) 3 6 6 3 7 <4 18 10 4 2 4 

Ba (mg/L) 170 63 60 85 <100 60 122 16 40 50 57 

Note: Values are not necessarily representative. Concentrations were determined from only one sample per ship class per constituent. 

NA : Information not available 

< : Less than 

Surface Vessel Bilgewater/Oil Water Separator (OWS) Discharge 

17 
Table 5. Ship Study OWS Influent and Effluent Contaminant Concentration Data5 

USS VINCENNES USS SAN JACINTO USS VANCOUVER USS PENSACOLA USS MANITOWOC 

Units 

(CG 49) (CG 56) (LPD 2) (LSD 38) (LST 1180) 

Parameter Influent Effluent Influent Effluent Influent Effluent Influent Effluent Influent Effluent 

COD mg/L 660 530 810 760 900 780 520 470 2,800 1,600 

BOD 

TOC 

TSS 

O&G 

Ammonia 

Fecal Coliform 

mg/L 

mg/L 

mg/L 

mg/L 

mg/L 

cts/100 ml 

NA 

145 

34 

37 

2.2 

NA 

NA 

129 

38 

27 

1.1 

NA 

94 

56.8 

62 

143 

<0.10 

49 

6,740 

34.6 

19 

8 

<0.10 

94 

<142 

42 

123 

47 

0.18 

NA 

<142 

34 

62 

20 

0.29 

NA 

101 

39 

41 

10 

<0.10 

110 

98 

31 

29 

4 

<0.10 

49 

341 

570 

2,684 

2,593 

NA 

2 

335 

224 

114 

32 

NA 

240 

Total Phenols 

Cyanide 

mg/L 

mg/L 

130 

<10 

110 

<10 

10 

<10 

30 

10 

10 

<30 

10 

<50 

20 

10 

10 

40 

NA 

<10 

20 

NA 

Arsenic 

Barium 

Cadmium 

Chromium 

Copper 

Iron 

Lead 

Manganese 

Nickel 

Selenium 

Zinc 

mg/L 

mg/L 

mg/L 

mg/L 

mg/L 

mg/L 

mg/L 

mg/L 

mg/L 

mg/L 

mg/L 

4 

59 

9 

<10 

830 

770 

50 

230 

290 

3 

800 

6 

63 

10 

<10 

540 

810 

20 

220 

270 

<2 

810 

6 

20 

<5 

<10 

490 

280 

<20 

10 

100 

12 

80 

6 

60 

5 

<10 

430 

260 

<20 

20 

130 

8 

190 

8 

10 

<3 

<10 

2,930 

1,240 

40 

51 

310 

15 

670 

10 

16 

<3 

<10 

790 

1,130 

20 

61 

400 

17 

1,590 

4 

30 

<5 

<50 

560 

2,960 

<50 

80 

250 

2 

380 

4 

40 

<5 

<50 

300 

1,620 

<50 

110 

210 

2 

410 

6 

40 

17 

770 

430 

2,.900 

50 

250 

120 

40 

3,000 

2 

50 

14 

590 

360 

2,600 

<50 

210 

120 

40 

2,500 

Bis(2-ethylhexyl) phthalate 

4-Nitrophenol 

Phenanthrene 

1,2,4-Trichlorobenzene 

1,1,1- Trichloroethane 

mg/L 

mg/L 

mg/L 

mg/L 

mg/L 

<200 

<400 

<200 

<200 

<5 

<10 

<20 

23.7 

28.3 

<5 

<200 

<200 

<200 

<200 

<50 

<100 

<100 

<100 

<100 

<50 

11.2 

10 

<10 

<10 

NA 

61.8 

<20 

<10 

<10 

<5 

<100 

<100 

<100 

<100 

<50 

<100 

<100 

<100 

<100 

<500 

<200 

<200 

<200 

<200 

45,000 

<200 

<200 

<200 

<200 

6,000 

Alpha-BHC 

Beta- BHC 

Gamma-BHC 

Heptachlor 

Heptachlor Epoxide 

mg/L 

mg/L 

mg/L 

mg/L 

mg/L 

0.047 

<0.999 

<0.02 

0.460 

0.379 

0.077 

<0.580 

<0.02 

0.209 

0.274 

<0.05 

<0.5 

16 

<0.05 

<0.05 

<0.05 

<0.5 

60 

<0.05 

<0.05 

0.02 

4.45 

<0.02 

<0.02 

<0.02 

<0.02 

<0.10 

<0.02 

<0.02 

<0.02 

<0.05 

<12 

<0.05 

<0.05 

<0.05 

<0.05 

<5 

0.5 

<0.05 

<0.05 

<0.25 

<2.5 

<0.25 

<0.25 

<0.25 

<5 

<50 

<5 

<5 

<5 

NA = Data not available 

Note: Values are not necessarily representative. Concentrations were determined from only one sample per ship class per constituent. 

Surface Vessel Bilgewater/Oil Water Separator (OWS) Discharge 

18 
Table 6. Naval Station San Diego Bilgewater Characterization Data Summary6 

(Calendar Years 1993 through 1995) 

Parameter 

No. of 

Analyses 

Values Above MDL (units in mg/L) 

No. Of 

Values 

Min. Max. Median Std. Dev. 

Oil & Grease 

Phenols 

45 

83 

45 

12 

5 

15 

12,900 

901 

146 

116 

2,234 

0.309 

Antimony 

Arsenic 

Cadmium 

Chromium 

Copper 

Lead 

Nickel 

Selenium 

Silver 

Thallium 

Zinc 

(a) 

(a) 

84 

85 

85 

85 

85 

1 

84 

(a) 

82 

(a) 

(a) 

33 

31 

84 

52 

83 

0 

14 

(a) 

80 

(a) 

(a) 

10 

20 

10 

39 

20 

NA 

4 

(a) 

100 

80 

1 

610 

2,320 

80,400 

3,360 

10,300 

NA 

1,440 

277 

97,000 

(a) 

(a) 

20 

70 

420 

100 

150 

NA 

23 

(a) 

688 

(a) 

(a) 

118 

492 

9,250 

509 

1,590 

NA 

398 

(a) 

14,500 

Benzene 

Chloroform 

Ethyl Benzene 

Methylene Chloride 

Tetrachloroethane 

Toluene 

Xylene 

82 

81 

81 

68 

82 

80 

17 

29 

1 

38 

18 

7 

52 

12 

0.5 

47 

6 

5 

7 

5 

28 

179 

47 

1,360 

4,220 

74 

2,220 

9,440 

30 

47 

50 

16 

18 

77 

16 

42 

NA 

221 

1,000 

24 

383 

2,600 

2,4-Dimethyl Phenol 

Fluorene 

Naphthalene 

82 

83 

79 

14 

41 

37 

30 

5 

11 

840 

1,890 

3,070 

89 

42 

85 

23 

411 

613 

NOTES: (a) References contain summary tables and raw data laboratory logs that are incomplete.

 Summary tables indicate single peak results for antimony, arsenic and thallium in 1993.

 However, log sheets showing the corresponding data are not included. The above statistical

 analysis is based on log sheet data that was provided, except for the maximum values shown

 for the three metals, which were obtained from the PWC summary table for 1993.

 (b) NA = Information not available. 

Surface Vessel Bilgewater/Oil Water Separator (OWS) Discharge 

19 
---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

Table 7. Navy Destroyer (DDG 64) OWS Effluent Discharge Data Summary7 

May to September, 1996 

Parameter No. of 

Analyses 

Values Above MDL (mg/L) 

No. Of 

Values 

Min. Max. Median Std. Dev. 

Oil in Water (Navy) 28 28 13 670 151 205 

Arsenic 11 6 10 70 20 23 

Barium 18 18 30 535 118 124 

Cadmium 18 3 10 10 10 NA 

Chromium 18 10 10 60 20 16 

Copper 18 18 430 6,110 1,.410 1,400 

Lead 18 15 10 195 40 62 

Iron 18 18 300 4,620 1,280 1,210 

Manganese 18 18 20 150 48 41 

Mercury 18 2 10 10 10 NA 

Nickel 18 18 140 1,510 320 317 

Selenium 11 11 70 210 100 40 

Silver 18 1 10 10 10 NA 

Zinc 18 18 480 8,880 2,190 1,930 

July 30, 1996 (mg/L) 

Sample A Sample B Sample C 

Parameter NRL LLI NRL LLI NRL LLI 

Oil and Grease (EPA 418.1) 29 70 66 

Petroleum Hydrocarbons 38 73 70 

MBAS 0.13 0.11 0.16 

Benzene 79 50 77 49 70 55 

Ethylbenzene 71 59 59 54 64 54 

Methylene Chloride <5 64 <5 63 <5 20 

Toluene 170 80 170 78 150 81 

Xylene (total) 460 289 450 266 410 264 

Diethyl Phthalate <10 10 12 

2,4-Dimethylphenol 110 110 110 

Dimethyl Phthalate 11 12 13 

Fluorene 12 17 20 

Naphthalene 63 61 14 

Phenanthrene 16 27 30 

Phenol 46 47 30 

NOTES: (a) Volatile and semi-volatile analysis performed on random samples collected over two hour period. 

Sample A during first hour. Samples B and C during second hour.

 (b) LLI = Lancaster Labs Inc. NRL = Naval Research Laboratory.

 (c) --- = Samples were not analyzed by LLI for the parameters shown.

 (d) NA = Information not available

 (e) < = less than 

Surface Vessel Bilgewater/Oil Water Separator (OWS) Discharge 

20 
Table 8. Auxiliary Ship (AS 36) OWS Effluent Discharge Data Summary7 

(May 2 through September 12, 1996) 

Parameter Method No. of 

Values Above MDL (mg/L) 

No. of Min. Max. Median Std. 

Detection Level Analyses Values Dev. 

Oil in Water NA 44 44 0.5 93 5.4 20.1 

BOD NA 8 8 1 34 3.5 10.1 

COD NA 14 14 26 260 61 79.5 

TSS NA 10 10 1 57 12.5 16 

Antimony 600 14 0 NA NA NA NA 

Arsenic 10 14 0 NA NA NA NA 

Beryllium 5 14 0 NA NA NA NA 

Cadmium 10 14 0 NA NA NA NA 

Chromium 20 14 0 NA NA NA NA 

Copper NA 14 14 44 661 257 166 

Lead 100 14 0 NA NA NA NA 

Iron NA 11 11 786 2,200 1,050 427 

Mercury 0.2 14 1 1.6 1.6 NA NA 

Nickel NA 14 14 75 471 117 103 

Selenium 10/5 14 0 NA NA NA NA 

Silver 30 14 0 NA NA NA NA 

Thallium 10 14 14 NA NA NA NA 

Zinc NA 14 14 164 1,100 382 283 

NOTE: NA = Information not available. 

Surface Vessel Bilgewater/Oil Water Separator (OWS) Discharge 

21 
Table 9. Aircraft Carrier (CVN 74)

Oil/Water Separator Influent/Effluent Raw Data4

CVN 74-OWSI-01 CVN 74-OWSI-02 CVN 74-OWSI-03 CVN 74-OWSI-04 

Parameter Units Influent Effluent Influent Effluent Influent Effluent Influent Effluent 

COD mg/L 132 179 258 258 86 148 195 148 

BOD mg/L 31 5 17 11 18 18 22 10 

TOC mg/L 28 9 24 21 26 20 19 11 

TSS mg/L 38 64 38 46 36 48 70 23 

O&G mg/L 50 22 269 17 42 36 122 27 

TKN mg/L 1.6 1.7 2.0 1.7 1.4 1.6 1.2 1.0 

Ammonia mg/L 0.14 <0.10 0.19 0.17 0.15 0.17 <0.10 <0.10 

Nitrate + Nitrite (As N) mg/L 054 0.20 0.44 0.30 0.50 0.40 0.62 0.0 

Total Phosphorous mg/L 3.2 1.2 3.7 2.7 3.9 2.2 3.1 2.0 

TDS mg/L 7,360 16,620 5,570 9,720 5,920 10,260 8,970 13,320 

Chloride mg/L 4,126 9,742 3,616 7,359 3,531 8,125 3,956 8,040 

Sulfate mg/L 498 1,290 411 643 446 780 643 958 

Sulfide mg/L 5 2 10 8 10 8 10 5 

Total Alkalinity mg/L 36 64 40 46 40 48 48 58 

Cyanide mg/L <10 <10 <10 <10 <10 <10 NA <10 

Aluminum 

Antimony 

Arsenic 

Barium 

Beryllium 

Cadmium 

Chromium 

Copper 

Iron 

Lead 

Manganese 

Nickel 

Selenium 

Silver 

Thallium 

Zinc 

mg/L 

mg/L 

mg/L 

mg/L 

mg/L 

mg/L 

mg/L 

mg/L 

mg/L 

mg/L 

mg/L 

mg/L 

mg/L 

mg/L 

mg/L 

mg/L 

69(B) 

<20 

<10 

49 

1(B) 

6 

<10 

581 

455 

<46 

34 

304 

<20 

5(B) 

<10 

1,590 

229 

<2 

33 

32 

<1 

<5 

<10 

284 

482 

<46 

29 

98 

<20 

<5 

<10 

519 

74(B) 

<20 

<1 

50(B) 

<1 

5.7 

<10 

567 

471 

<46 

34 

318 

<31.5 

<5 

<10 

1,760 

108(B) 

2.6(B) 

3(C) 

43(B) 

<1 

<5 

<10 

426 

442 

<46 

33 

245 

41(C) 

5(B) 

<10 

1,330 

83(B) 

5.6(B) 

<1 

55(B) 

<1 

5.1 

<10 

554 

560 

<46 

37 

321 

<20 

<5 

<10 

1,840 

104(B) 

<20 

33(B) 

40(B) 

<1 

5.6 

<10 

363 

432 

<46 

30 

208 

<20 

<5 

<10 

1,110 

143(B) 

<20 

<1 

44(B) 

<1 

<5 

<10 

574 

610 

<46 

35 

277 

26(C) 

<5 

<10 

1,350 

220 

<10 

<1 

34(B) 

<1 

<5 

<10 

316 

531 

<46 

31 

162 

<20 

<5 

<10 

786 

Bis(2-ethylhexyl) phthalate 

N,N-Dimethylformamide 

Toluene 

Xylene (o+p) 

mg/L 

mg/L 

mg/L 

mg/L 

<10 

99 

14 

24 

<10 

33 

<10 

<10 

30 

124 

12 

20 

<10 

88 

<10 

13 

22 

102 

13 

19 

<10 

65 

<10 

<10 

38 

85 

12 

19 

<10 

58 

<10 

12 

Note: (a) < = less than 

Surface Vessel Bilgewater/Oil Water Separator (OWS) Discharge 

22 
Table 10. Summary of Detected Analytes: Oil/Water Separator Effluent Data 

Constituent Log Normal 

Mean 

Frequency of 

Detection 

Minimum 

Concentration 

Maximum 

Concentration 

Mass 

Loading 

(lbs/yr) 

Oil Water Separator Effluent 

Classicals (mg/L) 

ALKALINITY 53.51 4 of 4 46 64 40,013 

AMMONIA AS NITROGEN 0.09 2 of 4 BDL 0.17 67 

BIOCHEMICAL OXYGEN 

DEMAND 

8.78 3 of 4 BDL 18 6,565 

CHEMICAL OXYGEN 

DEMAND (COD) 

178.34 4 of 4 148 258 133,356 

CHLORIDE 8273.63 4 of 4 7360 9740 6,186,728 

HEXANE EXTRACTABLE 

MATERIAL 

23.54 4 of 4 17.5 27 17,602 

NITRATE/NITRITE 0.27 4 of 4 0.2 0.4 202 

SGT-HEM 9.64 4 of 4 6 16 7,208 

SULFATE 887.29 4 of 4 643 1290 663,484 

TOTAL DISSOLVED SOLIDS 13238.57 4 of 4 9720 21600 9,899,334 

TOTAL KJELDAHL NITROGEN 1.5 4 of 4 1.1 1.7 1,122 

TOTAL ORGANIC CARBON 

(TOC) 

14.53 4 of 4 9.3 21 10,865 

TOTAL PHOSPHOROUS 1.81 4 of 4 1.2 2.7 1,353 

TOTAL RECOVERABLE OIL 

AND GREASE 

39.96 4 of 4 15.05 173 29,881 

TOTAL SULFIDE 

(IODOMETRIC) 

5.03 4 of 4 2 8 3,761 

TOTAL SUSPENDED SOLIDS 42.46 4 of 4 23 64 31,750 

VOLATILE RESIDUE 13285.59 4 of 4 9770 21600 9,934,494 

Hydrazine (mg/L) 

HYDRAZINE 0.15 4 of 4 0.095 0.2 112 

Mercury (ng/L) 

MERCURY 51.8 4 of 4 32.05 79.8 0.04 

Metals (mg/L) 

ALUMINUM 

Total 154.49 4 of 4 104 230.5 116 

ANTIMONY 

Total 6.15 1 of 4 BDL 2.6 5 

ARSENIC 

Total 6.09 2 of 4 BDL 33 5 

BARIUM 

Dissolved 34.98 4 of 4 27.8 41.8 26 

Total 36.58 4 of 4 30.65 42.9 27 

BORON 

Dissolved 1562.43 4 of 4 1280 2030 1,168 

Total 1505.6 4 of 4 1240 1945 1,126 

Surface Vessel Bilgewater/Oil Water Separator (OWS) Discharge 

23 
CADMIUM 

Total 3.06 1 of 4 BDL 5.6 2 

CALCIUM 

Dissolved 135123.39 4 of 4 105000 184000 101,040 

Total 129848.08 4 of 4 104000 172500 97,096 

COPPER 

Dissolved 162.56 4 of 4 116 201 122 

Total 341.25 4 of 4 277.5 426 255 

IRON 

Total 472.36 4 of 4 432 531 353 

MAGNESIUM 

Dissolved 392878.32 4 of 4 262000 486000 293,780 

Total 423465.92 4 of 4 333000 593500 316,653 

MANGANESE 

Dissolved 26.21 4 of 4 22.2 31.1 20 

Total 30.35 4 of 4 28.25 32.5 23 

MOLYBDENUM 

Dissolved 21.29 4 of 4 18.6 24.3 16 

Total 9.29 2 of 4 BDL 28.1 7 

NICKEL 

Dissolved 176.4 4 of 4 109 247 132 

Total 168.54 4 of 4 97.75 245 126 

SODIUM 

Dissolved 3606853.89 4 of 4 2680000 5200000 2,697,078 

Total 3585080.31 4 of 4 2770000 5000000 2,680,796 

TIN 

Total 16.59 1 of 4 BDL 41.2 12 

TITANIUM 

Total 4.5 2 of 4 BDL 9.2 3 

ZINC 

Dissolved 855.7 4 of 4 511 1260 640 

Total 878.8 4 of 4 514 1330 657 

Organics (mg/L) 

N,N-DIMETHYLFORMAMIDE 57.3 4 of 4 32.5 88 43 

O+P XYLENE 7.9 2 of 4 BDL 13 6 

Pesticides (mg/L) 

2,4-DB 1.66 2 of 4 BDL 2.88 1 

DICAMBA 0.29 3 of 4 BDL 0.48 0.2 

MCPA 28.45 1 of 4 BDL 58.9 21 

MCPP 113.25 4 of 4 41.3 167 85 

PYRETHRIN I 183 1 of 1 183 183 137 

Log normal means were calculated using measured analyte concentrations. When a sample set contained one or 

more samples with the analyte below detection levels (i.e., "non-detect" samples), estimated analyte concentrations 

equivalent to one-half of the detection levels were used to calculate the mean. For example, if a "non-detect" sample 

was analyzed using a technique with a detection level of 20 mg/L, 10 mg/L was used in the log normal mean 

calculation. 

Surface Vessel Bilgewater/Oil Water Separator (OWS) Discharge 

24 
Table 10 a. Estimated Annual Mass Loadings of Constituents 

Constituent Log Normal 

Mean 

Frequency of 

Detection 

Minimum 

Concentration 

Maximum 

Concentration 

Mass Loading 

(lbs/yr) 

Classicals (mg/L) 

AMMONIA AS NITROGEN 0.09 2 of 4 BDL 0.17 67 

NITRATE/NIRITE 0.27 4 of 4 0.2 0.4 202 

TOTAL KJELDAHL 

NITROGEN 

1.5 4 of 4 1.1 1.7 1,122 

TOTAL NITROGENA 1.77 1,304 

TOTAL PHOSPHOROUS 1.81 4 of 4 1.2 2.7 1,353 

SGT-HEM 9.64 4 of 4 6 16 7,208 

Mercury (ng/L) 

MERCURY 51.8 4 of 4 32.05 79.8 0.04 

Metals (mg/L) 

COPPER

 Dissolved 162.56 4 of 4 116 201 122

 Total 341.25 4 of 4 277.5 426 255 

IRON

 Total 472.36 4 of 4 432 531 353 

NICKEL

 Dissolved 176.4 4 of 4 109 247 132

 Total 168.54 4 of 4 97.75 245 126 

ZINC

 Dissolved 855.7 4 of 4 511 1260 640

 Total 878.8 4 of 4 514 1330 657 

Notes:

A - Total Nitrogen is the sum of Nitrate/Nitrite and Total Kjeldahl Nitrogen.

Surface Vessel Bilgewater/Oil Water Separator (OWS) Discharge 

25 
Table 11. Mean Concentrations of Constituents that Exceed Water Quality Criteria 

Constituent Log Minimum Maximum Federal Acute Water Quality Most Stringent State 

Normal Concentration Concentration Criteria Acute Water Quality 

Mean Criteria 

Classicals (mg/L) 

AMMONIA AS 0.09 BDL 0.17 None 0.006 (HI)A 

NITROGEN 

NITRATE/NITRITE 0.27 0.2 0.4 None 0.008 (HI)A 

TOTAL KJELDAHL 1.5 1.1 1.7 None -

NITROGEN 

TOTAL 1.77 None 0.2 (HI)A 

NITROGENB 

TOTAL 1.81 1.2 2.7 None 0.025 (HI)A 

PHOSPHOROUS 

TPH (SGT-HEM) 9.64 6 16 visible sheena

 / 15b 5 (FL) 

Mercury (ng/L) 

MERCURY* 51.8 32.05 79.8 1800 25 (FL, GA) 

Metals (mg/L) 

COPPER

 Dissolved 162.56 116 201 2.4 2.4 (CT, MS)

 Total 341.25 277.5 426 2.9 2.5 (WA) 

IRON

 Total 472.36 432 531 None 300 (FL) 

NICKEL

 Dissolved 176.4 109 247 74 74 (CA, CT)

 Total 168.54 97.75 245 74.6 8.3 (FL, GA) 

ZINC

 Dissolved 855.7 511 1260 90 90 (CA, CT, MS)

 Total 878.8 514 1330 95.1 84.6 (WA) 

Refer to federal criteria promulgated by EPA in its National Toxics Rule, 40 CFR 131.36 (57 FR 60848; Dec. 22,

1992 and 60 FR 22230; May 4, 1995)

A - Nutrient criteria are not specified as acute or chronic values.

B - Total Nitrogen is the sum of Nitrate/Nitrite and Total Kjeldahl Nitrogen.

* - Mercury was not found in excess of WQC; concentration is shown only because it is a bioaccumulator.

CA= California

CT = Connecticut

FL = Florida

GA = Georgia

HI = Hawaii

MS = Mississippi

WA = Washington

a Discharge of Oil, 40 CFR 110, defines a prohibited discharge of oil as any discharge sufficient to cause a sheen 

on receiving waters. b International Convention for the Prevention of Pollution from Ships (MARPOL 73/78). MARPOL 73/78 as 

implemented by the Act to Prevent Pollution from Ships (APPS) 

Surface Vessel Bilgewater/Oil Water Separator (OWS) Discharge 

26 
Table 12. Data Sources 

Data Source 

NOD Section Reported Sampling Estimated Equipment Expert 

2.1 Equipment Description and 

Operation 

Equipment 

Literature 

X 

2.2 Releases to the Environment OPNAVINST 

5090.1B 

X 

2.3 Vessels Producing the Discharge UNDS Database X 

3.1 Locality X 

3.2 Rate X X X 

3.3 Constituents X X X 

3.4 Concentrations X X 

4.1 Mass Loading X X 

4.2 Environmental Concentrations X X 

4.3 Potential for Introducing NonIndigenous Species X 

Surface Vessel Bilgewater/Oil Water Separator (OWS) Discharge 

27