LESSON 8

DIRECT THE LOADING AND UNLOADING OF WATERBORNE BARGES AND TANKERS

The handling of petroleum products around waterfront terminals must be carefully controlled in order to accurately account for the quantities delivered and issued, verify the quality of the products in transition, and to prevent spills.

This lesson covers the procedures for directing the loading and unloading operations of waterborne barges and tankers.

Terminal Learning Objective:

INTRODUCTION

More than half the tonnage handled in the military is petroleum. To do your job as a supervisor, you must know the responsibilities and procedures for loading and unloading petroleum tankers and barges.

PART A - TANKERS

The Military Sealift Command (MSC) controlled tanker fleet provides worldwide transportation for the delivery of petroleum products from refineries to Department of Defense (DOD) storage facilities. The tanker fleet consists of approximately 30 tankers, which vary in size from 27,000 to 38,000 tons. The various types of lease contracts are as follows:

• Bareboat Charter - The tanker is leased to MSC and MSC personnel crew the ship and are responsible for all expenses.
• Time Charter - From a few weeks to a number of years the owner provides the crew and pays all expenses.
• Single Voyage Charter - The ship is leased for a single voyage and the owner is responsible for the crew and all expenses.
• Dirty Service - For heating oils and crude service.
• Clean Service - For finished products only. Ships cannot carry split cargoes without prior approval from the Defense Energy Supply Center (DESC).

When referring to various locations on a ship, or when describing certain conditions of the ship, the following terms are used:

• Bow - Front end vessel
• Stern - Rear end of the vessel, also called the "aft section"
• Midships - Center of the vessel
• Port - The left side of the ship when standing midships and facing the bow.
• Starboard - The right side of the ship when standing midships and facing the bow.
• Bunkering - The fuel that is used to power the ship.
• Gross Tonnage - The total internal cubic capacity of a vessel less exempted spaces, such as tanks for ballast water. This weight is expressed in units of 100 cubic feet per ton.
• Net Tonnage - The registered tonnage of a ship after deductions have been made from the gross tonnage. Examples of deductions are crew and navigation spaces.
• Light Displacement - The weight of the vessel. This does not include the weight of cargo, passengers, fuel, water, stores, and other items that are needed on a voyage.
• Loaded Displacement - The total weight of the vessel. This includes the weight of cargo, passengers, fuel, water, stores, and other items that are needed on a voyage.
• Deadweight Tonnage - The carrying capacity of a vessel in long tons (2,240 pounds). It is the difference between light and loaded displacement.

PART B - BARGES, PUMP, TANKS, AND MANIFOLDS

Barges.

• Self propelled. These barges move under their own power and are used in inland and coastal waterways. They must maintain a crew at all times.
• Non-self propelled. They must be moved by tugboats, and can be used for temporary storage. They are equipped with their own pumping systems.

Pumps. Most tankers have two pumping systems.

• Centrifugal pumps for off loading the cargo.
• Gear or piston pumps for stripping the cargo tanks dry.

Ship’s Tanks and Manifolds. Most tankers have the capability to carry up to five different products. Ships' tanks are arranged abreast and numbered from bow to stern.

PART C - WATERFRONT FACILITIES

• Multileg mooring systems.
• Single point mooring systems (mono buoy).
• Jetties: Jetties are used when the water depth or the shore line is unsuitable for bringing in tankers.
• Docks and piers: Docks or piers are the most secure for unloading tankers. Security is easier to maintain. Access to the tanker is easier in case of emergency and for maintenance. They are protected from winds and tide and should be separated from other classes of supply. The depth should be at least ten feet of water under the biggest tanker you expect to receive fully loaded at mean low tide (Figure 8-1).

Figure 8-1. Layout of marine dock facilities for tanker unloading.

PART D - EQUIPMENT REQUIREMENTS

• Storage tanks. Minimum of two tanks for each product and ballast water.
• Oily water separator for treatment of ballast water.
• Fire fighting equipment. Portable fire extinguishers and an engineer fire fighting detachment.
• Pollution control equipment. Skimmer boats, sorbent materials, and containment booms.
• Communications. Communications have to be from the dock to the ship and to the tank farm.
• Transportation. Ground transportation and workboats for transporting men and equipment to the tanker.
• Grounding system. For bonding the ship to the dock. If the dock has a cathodic protection system it should be turned off before the transfer of fuel begins.
• Base laboratory. A lab should be available for testing the products.

PART E - PREPARATION FOR ARRIVAL

The tanker arrival schedule is checked to ensure the type and quantity of product is known. Personnel are required to meet the tanker and go aboard in the harbor. A terminal representative, lab technician, and customs official may also be required. Make sure the berthing facilities are cleared for the tanker to tie up. The cargo loading arms will be checked and maintenance performed. If cargo hoses are to be used, they will be pressure tested and the flanges checked. Shore tanks are gaged and sampled and product is transferred to create ullage if required. All pipelines and manifolds are checked and packed with product to the dock. Maintenance is performed on all pumps and all gages are checked. All communications are checked from the dock to the vessel and to the tank farm. Booms and skimmer boats are made ready to be deployed. Portable fire extinguishers are placed at all critical locations.

The terminal commander is responsible for all operations starting at the ship’s manifold:

• Pipeline patrol.
• Hose watch.
• Shift changes.

The master of the vessel is responsible for all shipboard actions. Paper work includes the tanker activity report and DD Form 250-1 (Tanker/Barge Material Inspection and Receiving Report). The tanker activity report is used as a worksheet to fill in DD Form 250-1. Information concerning the completion of DD Form 250-1 can be found in AR 710-2-1.

PART F - UNLOADING PROCEDURES

As the supervisor, you are to ensure that all environmental and safety procedures are observed and that any infractions are immediately corrected. All spills will be cleaned up and reported IAW applicable regulations and procedures.

• Valve seals. Prior to unloading, the valves aboard the vessel are checked to ensure they have been sealed and the seal numbers have been recorded on DD Form 250-1.
• Pumping. For JP-4, pumping will commence at a reduced flow rate not to exceed three feet per second until the fill line in the tank is covered with fuel.
• Delays. Any delays will be recorded in the time section of DD Form 250-1. This may determine who pays demurrage.
• Stripping. Once the centrifugal pumps lose suction the stripper pumps are brought on line and the tanks are pumped dry.
• Completion of off loading. When the ships' tanks are empty, they are inspected by terminal personnel and a dry tank certificate is issued. If product is found in a tank and cannot be removed the fact is recorded in the remarks section of the DD Form 250-1.
• Gaging of shore tanks. After the proper settling time, the shore tanks are gaged and the amount is recorded on the DD Form 250-1. If the amount received is less than that recorded on the DD Form 250-1 as loaded, and the shortage is more than one half of one percent it will require an investigation by the applicable DFSC fuel region upon receipt of the DD Form 250-1. For this reason the inventories and submission of the paper work must be done as soon as possible.
• Departure. After the tanker has departed, the pier is cleaned up and made ready for the next operation.

PART G - LOADING PROCEDURES

• As soon as the vessel is docked, the terminal commander or his representative should check the cargo to determine which product will be loaded first. This action will be mutually agreed upon.
• Ballast. The shore ballast tanks should be checked to ensure that enough ullage is available to accept ballast from the tanker.
• Checking ship’s tanks. The ship’s tanks should be checked to ensure they are clean and free of ballast and suitable for receiving product.
• Pumping. Follow the same procedures as for unloading.
• When tanks are 90 percent full, reduce the pumping rate to avoid spills or overflow.
• Follow up procedures. Allow enough time for tanks to settle before gaging each tank. Calculate the quantity loaded.
• Obtain an all-levels sample from each compartment and run a type c test according to MIL HDBK 200.
• Gage shore tanks and compare quantities pumped with quantities received.
• After the product quality and quantity have been determined, check and seal all hatches, seal valves and crossovers, and record all seal numbers on the DD Form 250-1.

Practice Exercise