[Federal Register Volume 60, Number 161 (Monday, August 21, 1995)]
[Proposed Rules]
[Pages 43427-43430]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-20619]



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DEPARTMENT OF TRANSPORTATION
46 CFR Part 32

[CGD 90-071]
RIN 2115-AD69


Tank Level or Pressure Monitoring Devices

AGENCY: Coast Guard, DOT.

ACTION: Notice of proposed rulemaking.

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SUMMARY: The Coast Guard proposes minimum standards for tank level or 
pressure monitoring devices to be used on tank vessels. The purpose of 
the devices is to reduce the size and impact of oil spills by alerting 
the tank vessel operator that an accidental discharge of cargo oil is 
occurring. Requirements for the installation and use of the devices 
will be proposed separately.


[[Page 43428]]

DATES: Comments must be received by November 20, 1995.

ADDRESSES: Comments may be mailed to the Executive Secretary, Marine 
Safety Council (G-LRA/3406) (CGD 90-071), U.S. Coast Guard 
Headquarters, 2100 Second Street, SW., Washington, DC 20593-0001, or 
may be delivered to room 3406 at the same address between 8 a.m. to 3 
p.m., Monday through Friday, except Federal holidays. The telephone 
number is (202) 267-1477.
    The Executive Secretary maintains the public docket for this 
rulemaking. Comments will become part of the docket and will be 
available for inspection and copying at room 3406, U.S. Coast Guard 
Headquarters between 8 a.m. and 3 p.m. Monday through Friday, except 
Federal holidays.

FOR FURTHER INFORMATION CONTACT: Randall N. Crenwelge, Project Manager, 
Oil Pollution Act Staff (G-MS), (202) 267-6220.

SUPPLEMENTARY INFORMATION:

Request for Comments

    The Coast Guard encourages interested persons to participate in 
this rulemaking by submitting written data, views, or arguments. 
Persons submitting comments should include their names and addresses, 
identify this rulemaking (CGD 90-071) and the specific section of this 
proposal to which each comment applies, and give the reason for each 
comment. Please submit two copies of all comments and attachments in an 
unbound format, no larger than 8\1/2\ by 11 inches, suitable for 
copying and electronic filing. Persons wanting acknowledgment of 
receipt of comments should enclose a stamped, self-addressed postcard 
or envelope.
    The Coast Guard will consider all comments received during the 
comment period. It may change this proposal in view of the comments.
Background and Purpose

    Section 4110 of the Oil Pollution Act of 1990 (OPA 90) (Pub. L. 
101-380), found as a statutory note following 46 U.S.C. 3703, addresses 
two regulatory initiatives concerning tank level or pressure monitoring 
devices. The first requires the establishment of minimum standards for 
tank level or pressure monitoring devices. The second initiative calls 
for requirements concerning the use of the devices on tank vessels.
    Tank level or pressure monitoring devices detect leaks in cargo 
tanks. The purpose of leak detection devices is to inform a person in 
charge of a tank vessel that a leak is occurring so that the Coast 
Guard can be notified as required by 33 CFR 153.203, and appropriate 
response actions can be initiated.
    The Coast Guard previously published an advance notice of proposed 
rulemaking (ANPRM) to solicit comment on minimum standards for leak 
detection devices and their use (56 FR 21116; May 7, 1991).
    The Coast Guard received twenty comments to the ANPRM. Fourteen 
comments were from tank vessel operators, environmental groups, and 
industry organizations. Four comments were submitted by tank level or 
pressure monitoring device manufacturers. Two comments were received 
from marine consultants.
    The Coast Guard also commissioned a study regarding the technical 
feasibility and accuracy of the devices. A notice of the availability 
of the study was published on February 5, 1993 (58 FR 7292).

Technical Feasibility Study

    The Coast Guard's technical feasibility study, ``Tank Level 
Detection Devices for the Carriage of Oil,'' examined a wide variety of 
liquid level sensing systems for application as leak detection devices 
including hydrostatic gauges, radar gauging measures, resistance tape, 
floats, ultrasonic systems, fiber optics, capacitance-actuated devices, 
and the Electromagnetic level indication (EMLI) system.
    In addition to discussing the wide variety of currently available 
liquid level detectors, the study evaluated the performance of these 
sensors using both ideal conditions and simulated conditions 
(environmental noise, ship motion, etc.). The effects of these 
conditions varied depending on the system. In some circumstances, 
environmental noise was found to substantially degrade performance.
    The study found that the greatest obstacle to obtaining an accurate 
level reading is the disturbance of the cargo surface caused by ship or 
barge motion. The study indicated that sloshing occurs in all tank 
vessels to varying degrees, depending on such factors as vessel type, 
weather conditions, and loading configurations. The effects of such 
motion must be considered in determining the attainable accuracy of 
level sensing for use in leak detection.
    The study found that another result of ship motion is the formation 
of foam, which can reduce the accuracy of any type of electronic 
surface level sensing. Disturbance of the surface can also cause 
pocketing of air, which also results in a loss of measurement accuracy.
    A third effect of vessel motion discussed by the study is vertical 
acceleration of the liquid in the cargo tanks, caused by surging 
rolling, and pitching. This vertical acceleration is extremely dynamic 
and can cause wide variations in the hydrostatic data produced by the 
pressure sensors. Appreciable acceleration of the cargo also occurs at 
lower sea states and significantly degrades the accuracy of a 
hydrostatic measuring system. In these conditions, the liquid 
measurement by currently available devices may degrade up to 10 
percent.
    The study concluded that, under good conditions, a change of cargo 
level of at least one to two percent is necessary before current 
devices can be expected to detect the change.
    The Coast Guard announced in the November 15, 1994 Federal Register 
(59 FR 58810) that it would hold a public meeting to seek additional 
comments with regard to standards for and the use of tank level or 
pressure monitoring devices. The meeting was held on December 9, 1994. 
The meeting gave the public the opportunity to provide further input 
into the development of proposed regulations.
    The Coast Guard received nine comments at the public meeting. Seven 
came from tank vessel owners and operators, and two came from industry 
organizations.
Discussion of Comments

    The comments to the ANPRM and at the public meeting discussed a 
variety of topics including the scope of statutory authority, 
applicability, types of appropriate devices, factors affecting 
performance, sensitivity of available devices, and research and 
development efforts. Because this notice of proposed rulemaking (NPRM) 
covers standards for tank detection devices and not requirements for 
installation and use, only comments submitted regarding standards are 
addressed here. Other comments concerning the use of the devices on 
particular vessels will be addressed in a subsequent rulemaking.
    Several comments to the ANPRM requested that the Coast Guard list 
the types of devices which it considered in drafting the ANPRM. The 
devices included hydrostatic gauges, radar, resistance tape, floats, 
ultrasonic systems, fiber optics, capacitance-actuated devices, and the 
EMLI system. All of these devices were discussed in the technical 
feasibility study commissioned by the Coast Guard and made available to 
the public. The results of the study are discussed earlier in the NPRM 
under the heading ``Technical Feasibility Study.''

[[Page 43429]]

    One comment suggested a device which relies on the electrical 
conductivity of water on its dielectric properties to measure the water 
level in the bottom of a crude carrier. Currently, this technology has 
not been proven in shipboard applications. As described later, the 
Coast Guard is proposing a standard that would not be limited to a 
specific technology.
    Another comment noted that one device might meet standards for both 
leak detection and overfill warning. The Coast Guard would permit such 
a device if it could meet all requirements. Requirements for overfill 
devices also were issued under the authority of section 4110 of OPA 90 
(59 FR 53286; October 21, 1994) and are found at 33 CFR 155.750.
    Several comments challenged the need to set standards for detection 
devices to achieve the purpose of section 4110 of OPA 90. These 
comments indicated that the current industry standard requires 
surveillance whenever there is petroleum oil cargo aboard a tank barge. 
They further stated that when there is a custody transfer of a barge 
and its cargo, the material condition of the barge is checked to ensure 
that there are no leaks or other damage to the barge. The comments 
pointed out that there are many instances in day-to-day operations when 
barges are inspected. Industry representatives stated at the public 
meeting that inspections will detect leaks or other damage before 
significant harm is done to the environment. They also stated that 
during cargo transfers, independent surveyors and the cargo master are 
present to account for all cargo.
    The Coast Guard notes the ongoing efforts of the owners and 
operators of tank barges, fleeting services, and terminals to reduce 
oil pollution through operational procedures. Compliance with existing 
requirements and voluntary industry efforts to improve performance 
greatly enhance the quality of the marine environment. However, the 
language and intent of section 4110 or OPA 90 does not address 
operational measures, but rather clearly directs the Coast Guard to 
develop standards for leak detection devices.
    One comment asked the Coast Guard to approve specific devices. 
While this rulemaking only proposes standards, the Coast Guard 
recognizes that appropriate testing and approval of devices that meet 
final Coast Guard standards will be a necessary component of any 
subsequent requirements for use of the devices. The Coast Guard is in 
the process of converting its existing equipment approval program into 
an equipment acceptance program which is based on industry consensus 
standards. Accordingly, the Coast Guard will begin working with 
appropriate industry and third-party standards groups to implement an 
acceptance program for leak detection devices to be proposed later 
along with regulations for installation and use of these devices.
    One comment noted that accurate cargo measurement is difficult when 
a vessel is in transit. The comment contrasted sloshing of liquid in 
cargo tanks while a vessel is moving in a seaway with the stability of 
liquids in stationary shore tanks. Another comment contended that tank 
level devices cannot detect leaks, just significant changes in level 
from catastrophic losses.
    A third comment predicted that the average of levels sensed by a 
device would be lower than the actual level of liquid in the thank, as 
liquid moves from side to side in the tank. In contrast, four comments 
claimed that current devices may not be sensitive enough to detect 
leaks prior to a catastrophic spill. The Coast Guard agrees that 
currently available devices may not meet the proposed standards for 
meaningful and timely leak detection; however, establishing the 
standards may lead to development of devices which will provide 
appropriate leak detection.
    One comment said that inconvenience and time spent in responding to 
false alarms would be offset by the early response to an actual leak. 
Other comments argued that persistent false alarms could result in the 
crew failing to respond in the event of an actual leak. One comment 
also asserted that persistent false alarms may present a significant 
nuisance to shipboard watchstanders causing them to turn off the 
system. The Coast Guard agrees that frequent false alarms would 
significantly degrade the value of warning devices.
    Some comments noted that very few hull failures remain undetected. 
Since most hull failures are caused by groundings, collisions, and 
allisions, crews will notice these failures and respond quickly. The 
comments contained conflicting views as to whether tank level devices 
would be useful in the case of gross hull failures, such as that of 
Tank Barge 565 (discussed in the ANPRM). The Coast Guard agrees that 
some hull leaks may be detected by other means before a leak detection 
device signals an alarm. However, in some cases, a suitable device 
would signal a discharge of oil that would otherwise, as in the case of 
Tank Barge 565, go unnoticed by the crew.
    Some comments discussed new technology, such as the use of thermal 
conductivity. A majority of the comments stated that the technology for 
tank level or pressure monitoring devices is not currently available in 
a useful form for shipboard applications, and that further research and 
development are needed. The Coast Guard expects that research and 
development will improve the devices in the near term. The Coast Guard 
encourages continued research, development, testing, and evaluation of 
devices to meet the proposed requirements.
    The Coast Guard solicits comments on research and development 
efforts including current and future testing and evaluation of leak 
detection systems, components, algorithms, hardware, software, and 
devices. The Coast Guard also solicits comments on performance 
characteristics, limitations, suitability to different cargoes, design 
considerations, applicability, installation requirements, and costs.

Discussion of Proposed Rules

    This NPRM proposes standards for leak detection devices intended 
for installation on the cargo tanks on vessels carrying oil in bulk as 
cargo.
    The proposed regulations for leak detection devices would require 
both audible and visible alarms. The alarms would indicate that the 
liquid level within a cargo tank is dropping. The drop in level would 
mean that a probable leak is occurring.
    The Coast Guard proposes that a leak detection device must sound an 
alarm before the contents of the tank decline to a level 0.5 percent 
below the level at which the tank was loaded, or at the loss of 1,000 
gallons of cargo, whichever is less. The device must perform to this 
standard, notwithstanding sloshing and cargo temperature change.
    The 1,000 gallon threshold was chosen because a discharge of less 
than 1,000 gallons on the inland waterways is defined as a ``Minor 
Discharge'' in accordance with the National Contingency Plan, dated 
September 15, 1994 (59 FR 47384). A loss of 1,000 or more gallons in 
virtually all environments poses appreciable risk to the marine 
environment.
    The Coast Guard requests comments concerning this ``attainable 
accuracy'' requirement, as it applies to both inland and oceangoing 
vessels, and under sloshing conditions.

[[Page 43430]]


Proposed Subpart 32.22-01  Performance Standards for Cargo Leak 
Detection Devices

    This section would set standards for leak detection devices 
intended for installation in each cargo tank carrying oil. It requires 
the devices to be designed to automatically compensate for changes in 
cargo temperature; be intrinsically safe or explosion proof; indicate a 
power loss or failure of a circuit; monitor and self-test its 
circuitry; alarm before the contents of a tank drop more than 0.5 
percent below the level at which the tank was loaded or 1,000 gallons, 
whichever is less; be able to operate accurately in heavy seas or 
weather; and have audible and visible alarms.
    As noted under the discussion of comments, the Coast Guard will 
begin to develop a method for certifying that leak detection devices 
meet the standard proposed here as part of the process for developing 
follow-on regulations addressing installation and use of these devices. 
The Coast Guard expects that additional development and research will 
be necessary to produce devices that meet the standard proposed here.

Regulatory Evaluation

    This proposal is not a significant regulatory action under section 
3(f) of Executive Order 12866 and does not require an assessment of 
potential costs and benefits under section 6(a)(3) of that order. It 
has not been reviewed by the Office of Management and Budget under that 
order. It is not significant under the regulatory policies and 
procedures of the Department of Transportation (44 FR 11040; February 
26, 1979). The Coast Guard expects the economic impact of this rule to 
be so minimal that a full Regulatory Assessment under paragraph 10e of 
those policies is unnecessary. Costs associated with tank level or 
pressure monitoring devices are dependent on use requirements which 
will be established in a separate rulemaking.
Small Entities

    Under the Regulatory Flexibility Act (5 U.S.C. 601 et seq.), the 
Coast Guard must consider whether this proposal, if adopted, will have 
a significant economic impact on a substantial number of small 
entities. ``Small entities'' may include (1) small businesses and not-
for-profit organizations that are independently owned and operated and 
are not dominant in their fields and (2) small governmental 
jurisdictions.
    Because this proposal imposes no costs on any entities, including 
small entities, the Coast Guard certifies that this proposal would not 
have a significant economic impact on a substantial number of small 
entities.

Collection of Information

    This proposal contains no collection of information requirements 
under the Paperwork Reduction Act (44 U.S.C. 3501 et seq.).

Federalism

    The Coast Guard has analyzed this proposal under the principles and 
criteria contained in Executive Order 12612 and has determined that 
this proposal does not have sufficient federalism implications to 
warrant the preparation of a Federalism Assessment.

Environment

    The Coast Guard considered the environmental impact of this rule 
and concluded that, under paragraph 2.B.2e of Commandant Instruction 
M16475.1B, this rule is categorically excluded from further 
environmental documentation. This rule concerns only equipment 
approval. Approved equipment is expected to contribute to the reduction 
of the occurrence of ship-generated oil spills in the marine 
environment. A ``Categorical Exclusion Determination'' is available in 
the docket for inspection or copying where indicated under ADDRESSES.

List of Subjects in 46 CFR Part 32

    Cargo vessels, Fire prevention, Marine safety, Navigation (water), 
Occupational safety and health, Reporting and recordkeeping 
requirements, Seamen.

    For the reasons set out in the preamble, the Coast Guard proposes 
to amend 46 CFR part 32, as follows:

PART 32--SPECIAL EQUIPMENT, MACHINERY, AND HULL REQUIREMENTS

    1. The authority citation for 46 CFR part 32 is revised to read as 
follows:

    Authority: 46 U.S.C. 2103, 3306, 3703; E.O. 12234, 45 FR 58801, 
3 CFR, 1980 Comp., p. 277; 49 CFR 1.46; Subparts 32.22-1 and 32.59 
are also issued under 46 U.S.C. 3703 note.

    2. Subpart 32.22 is added to read as follows:

Subpart 32.22--Cargo Leak Detection


Sec. 32.22-1  Performance standards for cargo leak detection devices.

    (a) A cargo leak deduction device is a tank level or pressure 
monitoring device used to detect leaks in cargo tanks. The purpose of a 
cargo leak detection device is to inform a person in charge of a tank 
vessel that a leak is occurring so that the Coast Guard can be notified 
as required by 33 CFR 153.203, and appropriate response actions can be 
initiated.
    (b) A cargo leak detection device must meet the following 
standards:
    (1) Automatically compensate for changes in cargo volume due to 
temperature;
    (2) Be intrinsically safe in accordance with Sec. 111.105-11 of 
this chapter, or explosion proof in accordance with section 
Sec. 111.105-9 of this chapter;
    (3) Indicate the event of a loss of power or failure of the leak 
detection circuit, and monitor the condition of the alarm circuitry and 
sensor by an electronic self-testing feature;
    (4) Alarm before cargo in the cargo tank declines to a level of 0.5 
percent below the level at which it was loaded or before the loss of 
more than 1000 gallons of cargo from the tank, whichever is less;
    (5) Be designed to operate without degradation in heavy seas, 
moisture, and varying weather conditions; and
    (6) Have audible and visible alarm indicators that can be remotely 
installed.

    Dated: June 29, 1995.
G.N. Naccara,
Captain, U.S. Coast Guard, Acting Chief, Office of Marine Safety, 
Security and Environmental Protection.
[FR Doc. 95-20619 Filed 8-18-95; 8:45 am]
BILLING CODE 4910-4-M