[Federal Register Volume 76, Number 32 (Wednesday, February 16, 2011)]
[Proposed Rules]
[Pages 8923-8939]
[FR Doc No: 2011-3487]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 420

[Docket No. FAA-2011-0105; Notice No. 11-03]
RIN 2120-AJ73

Explosive Siting Requirements

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to abandon its separation requirements at
launch sites for storing liquid oxygen, nitrogen tetroxide, hydrogen
peroxide in concentrations equal to or below 91 percent, and refined
petroleum-1 (RP-1) unless they are within an intraline distance of
another incompatible energetic liquid, or will be co-located on a
launch vehicle. The FAA's current separation requirements for storing
these energetic liquids unnecessarily duplicate the requirements of
other regulatory regimes. The FAA also proposes to reduce the
separation distances required for division 1.1 explosives and liquid
propellants with trinitrotoluene (TNT) equivalents of less than or
equal to 450 pounds. The revised separation requirements reflect
protection against fragment hazards, the main hazard at these
quantities. The FAA would impose a new formula for determining
distances to public areas containing a member of the public in the
open. Finally, the FAA would reduce the separation distances for
division 1.3 explosives as well. The proposed rule would increase
flexibility for launch site operators in site planning for the storage
and handling of explosives.

DATES: Send your comments on or before May 17, 2011.

ADDRESSES: You may send comments identified by Docket Number FAA-2011-
0105 using any of the following methods:
     Federal eRulemaking Portal: Go to http://www.regulations.gov and follow the online instructions for sending your
comments electronically.
     Mail: Send comments to Docket Operations, M-30; U.S.
Department of Transportation, 1200 New Jersey Avenue, SE., Room W12-
140, West Building Ground Floor, Washington, DC 20590-0001.
     Hand Delivery or Courier: Take comments to Docket
Operations in Room W12-140 of the West Building Ground Floor at 1200
New Jersey Avenue, SE., Washington, DC, between 9 a.m. and 5 p.m.,
Monday through Friday, except Federal holidays.
     Fax: Fax comments to Docket Operations at<PHONE_NUMBER>.

For more information on the rulemaking process, see the SUPPLEMENTARY
INFORMATION section of this document.
    Privacy: We will post all comments we receive, without change, to
http://www.regulations.gov, including any personal information you
provide. Using the search function of the docket Web site, anyone can
find and read the electronic form of all comments received into any of
our dockets, including the name of the individual sending the comment
(or signing the comment for an association, business, labor union,
etc.). You may review DOT's complete Privacy Act Statement in the
Federal Register published on April 11, 2000 (65 FR 19477-78), or you
may visit http://DocketsInfo.dot.gov.
    Docket: To read background documents or comments received, go to
http://www.regulations.gov at any time and follow the online
instructions for accessing the docket or Docket Operations in Room W12-
140 of the West Building Ground Floor at 1200 New Jersey Avenue, SE.,
Washington, DC, between 9 a.m. and 5 p.m., Monday through Friday,
except Federal holidays.

FOR FURTHER INFORMATION CONTACT: For technical questions concerning
this proposed rule contact Charles Huet, Commercial Space
Transportation, Federal Aviation Administration, 800 Independence
Avenue, SW., Washington, DC 20591; telephone<PHONE_NUMBER>; facsimile
(202) 267-3686, e-mail<EMAIL_ADDRESS>For legal questions
concerning this proposed rule contact Laura Montgomery, AGC 200, Senior
Attorney for Commercial Space Transportation, Office of the Chief
Counsel, Federal Aviation Administration, 800 Independence Avenue, SW.,
Washington, DC 20591; telephone<PHONE_NUMBER>; facsimile (202) 267-
7971, e-mail<EMAIL_ADDRESS>
SUPPLEMENTARY INFORMATION: Later in this preamble under the Additional
Information section, we discuss how you can comment on this proposal
and how we will handle your comments. Included in this discussion is
related information about the docket, privacy, and the handling of
proprietary or confidential business information. We also discuss how
you can get a copy of related rulemaking documents.

Authority for This Rulemaking

    The Commercial Space Launch Act of 1984, as codified and amended in
Title 49 of the United States Code (49 U.S.C.) Subtitle IX--Commercial
Space Transportation, chapter 701, Commercial Space Launch Activities,
49 U.S.C. 70101-70121 (the Act), authorizes the Department of
Transportation and thus the FAA, through delegations, to oversee,
license, and regulate commercial launch and reentry activities, and the
operation of launch and reentry sites as carried out by U.S. citizens
or within the United States. 49 U.S.C. 70104, 70105. The Act directs
the FAA to exercise this responsibility consistent with public health
and safety, safety of property, and the national security and foreign
policy interests of the United States. 49 U.S.C. 70105. The FAA is also
responsible for encouraging, facilitating, and promoting commercial
space launches by the private sector. 49 U.S.C. 70103.
    Authority for this particular rulemaking is derived from 49 U.S.C.
70105, which requires that the FAA issue a license to operate a launch
site consistent with public health and safety. See also 49 U.S.C.
322(a), 49 U.S.C. 70101(a)(7). Section 70101(a)(7) directs the FAA to
regulate only to the extent necessary, in relevant part, to protect the
public health and safety and safety of property.

Background

    In 2000, the FAA issued regulations governing the storing and
handling of explosives as part of its regulations governing the
licensing and operation of a launch site. Licensing and Safety
Requirements for Operation of a Launch Site; Final Rule, 65 FR 62812
(Oct. 19, 2000) (Launch Site Rule). The FAA has requirements for
obtaining a license to operate a launch site in Title 14, Code of
Federal Regulations (14 CFR) part 420. Part of the application for a
license requires an applicant to provide the FAA with an explosive site
plan that complies with the explosive siting requirements of part 420.
The plan must show how a launch site operator will separate explosive
hazard facilities from the public. The plan must identify the location
of the explosives and how the public is safeguarded. The explosive
siting requirements of part 420 mandate how far apart a launch site
operator should site its explosive hazard facilities based on the
quantities of energetic materials housed in each facility. Distances
vary based on the quantities at issue, the storing or handling of the
energetic materials at a given facility, and whether or not the
distance being calculated is a distance to a public area.

    Since the original rulemaking, the FAA's experience with the
requirements has led it to propose changes. At the time it promulgated
the original requirements, the FAA anticipated that any new launch
sites would be devoted to expendable launch vehicles, and, therefore,
relied on the siting requirements of the Department of Defense (DOD)
Explosive Siting Board's (DDESB) DOD Ammunition and Explosive Safety
Standard, 6055.9-STD (1997) (1997 DOD Standard).\1\ Instead, for the
most part, the FAA has issued a number of licenses for the operation of
launch sites at existing airports, such as Mojave Air and Space Port.
At these airports, the presence of jet fuels regulated under existing
requirements creates conditions requiring the FAA to reconcile its
launch vehicle liquid propellant requirements with the presence of
other industrial chemicals, such as aircraft fuels. Based on experience
with these launch sites and on research on other regimes that address
explosive materials, the FAA proposes to make changes to its own
requirements.
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    \1\ The DDESB updated the DOD Standard in 2004. Notice of
Revision of Department of Defense 6055.9-STD Department of Defense
Ammunition and Explosives Safety Standards, 70 FR 24771 (May 11,
2005) (2004 DOD Standard). DOD released a new edition in 2008, but
the 2004 changes are the ones relevant to this rulemaking. The new
standard bases its separation distances on Occupational Safety and
Health Administration (OSHA) and National Fire Protection
Association (NFPA) standards for classes I through III flammable and
combustible liquids and liquid oxygen, and on NFPA standards for
classes 2 and 3 liquid oxidizers. The 2004 DOD Standard contains
less restrictive requirements for explosive division 1.1 solid
explosives with a net explosive weight of less than 450 pounds, and
for energetic liquids with a TNT equivalency of less than 450
pounds.
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    Changes to definitions would be changes of general effect.
Additionally, the FAA proposes to increase the flexibility it has in
applying its explosive siting requirements by recognizing that
approaches other than those mandated by part 420 may provide a level of
safety equivalent to part 420. The FAA also proposes to dispense with
separation distance requirements for storing liquid oxidizers and Class
I, II and III flammable and combustible liquids. When oxidizers are
isolated from incompatible energetic liquids and compliant with the
design and operational requirements of other regulatory regimes, they
do not pose a risk of fire or explosion. Isolating the storing of
liquid oxidizers from a fuel source minimizes the risk associated with
chemical explosion due to the mixing of the two. In accordance with
current DDESB and National Fire Protection Association (NFPA) practice,
the FAA proposes to dispense with the hazard groups of tables E-3
through E-6 of appendix E of part 420 as a means of classification
because the NFPA classification system is more commonly used. A number
of those changes are editorial, but the FAA also proposes to identify
the minimum separation distances to public areas and public traffic
routes for quantities between less than half a pound and 450 pounds of
division 1.1 explosives and liquid propellants with TNT equivalency.
The FAA would impose a new formula for determining distances to public
areas containing a member of the public in the open. The FAA also
proposes to change its separation requirements for division 1.3
explosives.

I. Changes of General Effect

    The FAA proposes to clarify an existing definition and to add four
new ones. We would clarify the meaning of ``explosive hazard
facility.'' We would define ``energetic liquid,'' ``liquid
propellant,'' ``maximum credible event,'' and ``public traffic route.''
    The FAA proposes to define ``energetic liquids'' to mean a liquid,
slurry, or gel, consisting of, or containing an explosive, oxidizer,
fuel, or combination, that may undergo, contribute to, or cause rapid
exothermic decomposition, deflagration, or detonation. ``Energetic
liquids'' would thus include liquid fuels and oxidizers,
monopropellant, hybrid, and liquid bipropellant systems.
    The FAA would define ``liquid propellants'' to mean a
monopropellant or incompatible energetic liquids co-located for
purposes of serving as propellants on a launch vehicle or a related
device,\2\ such as an attitude control propulsion system. A
monopropellant serves as a liquid propellant only if located on a
launch vehicle. When not located on a launch vehicle a monopropellant
is treated as a fuel or an oxidizer. Part 420 does not define ``liquid
propellant,'' but refers to liquid fuel and oxidizers as liquid
propellants whether stored in a storage tank and segregated from each
other, or co-located as part of a launch vehicle assembly. In applying
this term, the FAA has had to address uncertainty and confusion
regarding its meaning. When part 420 was issued, most launch operations
took place at federal launch ranges. There are now launch sites located
at airports that house many of the same energetic liquids. The term
``liquid propellant'' as it applies to storing liquid fuel and
oxidizer, such as kerosene and liquid oxygen, causes confusion.
Kerosene has found a use in some new developmental launch vehicles as a
liquid fuel, but is traditionally known for its use as a jet fuel.
Liquid oxygen is commonly used as the oxidizer for launch vehicles, but
is also widely used in the medical field and other industrial purposes.
The labeling of these materials as liquid propellants, is, therefore,
no longer suitable because of their multiple uses. To remove the
confusion, the FAA would classify what it has been generically
referring to as liquid propellants as energetic liquids, and would
limit the use of the term ``liquid propellant'' to its more precise
usage, namely, incompatible energetic liquids co-located for purposes
of propulsion or operating power in rockets and related devices. With
this definition, liquid fuels and oxidizers that are not yet part of a
vehicle assembly or a propulsion unit would not be referred to as a
liquid propellant, thus removing the ambiguity caused by the current
characterization of too many energetic liquids as liquid propellants.
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    \2\ A related device would include an engine undergoing engine
testing or static firing.
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    Limiting the use of the term would be more consistent with typical
uses of the term ``liquid propellants.'' Explosive siting experts
typically consider the term to mean incompatible energetic liquids that
are co-located for purposes of serving as propellants on a launch
vehicle. In other words, the same energetic liquid is a propellant if
on a rocket, but not if in a storage tank. This special meaning is not
obvious, but is understood by those persons who work on these issues.
The FAA proposes to confine use of the term to Sec.  420.69, which
governs launch pads where solid explosives and energetic liquids are
all within intraline distances of each other because they are used as
fuels for a launch vehicle.
    The FAA proposes to clarify that an ``explosive hazard facility''
means not only a facility, as identified in the present definition, but
a location at a launch site where solid explosives, energetic liquids,
or other explosives are stored or handled. Part 420 currently defines
an ``explosive hazard facility'' as a facility at a launch site where
solid propellant, liquid propellant, or other explosives are stored or
handled. There are circumstances where it is not always clear what
satisfies this definition. For example, under this definition,
explosive hazard facility could be misinterpreted to only apply to
buildings or storage sites. Clarifying that an explosive hazard
facility is not only a facility, but is also any other location, would
more clearly include hazardous

areas such as launch pads and static firing areas with explosives or
propellant present.
    The FAA proposes to define ``maximum credible event'' to mean a
hypothesized worst-case event, including an accident, explosion, fire,
or agent release that is likely to occur from a given quantity and
disposition of explosives, chemical agents, or reactive material. A
``maximum credible event'' is one with a reasonable probability of
occurring, taking into account the propagation of the predicted
explosion, burn rate, and physical protection such as barriers located
around the explosive materials.
    Although the FAA cites ``public traffic route distance'' in Sec.
420.65, there is no definition for the term in the current rule.
``Public traffic route'' means any road or other mode of transportation
on a launch site that serves the general public, and the FAA now
proposes to codify that working definition. A ``public traffic route''
is a public area, but one that may permit shorter separation distances
than other public areas due to the ability of a launch site operator to
close off the public traffic route and the sporadic presence of members
of the public.

II. Section 420.63 Map Scale and Equivalent Level of Safety

    Section 420.63 contains general requirements applicable to the
preparation of an explosive siting plan, the explosive siting
requirements for a launch site located on a federal range, and
provision for establishing an equivalent level of safety for explosive
siting issues not otherwise addressed by part 420. The FAA proposes
only editorial changes to its explosive siting requirements at Sec.
420.63, with two exceptions. The first is that the FAA proposes an
explosive site map using a scale sufficient to show distance and
structural relationships. The other substantive change would be
proposed paragraph (d), which would allow a launch site operator to
propose a different separation distance if able to clearly and
convincingly demonstrate level of safety equivalent to that required by
part 420.
    The FAA proposes to require an explosive site map using a scale
sufficient to show whether distances and structural relationships
satisfy the requirements of this part. The FAA has had difficulty
reviewing explosive site maps provided by some launch operators because
they employed scales where 1 inch equaled 1500 feet or more. As a
result, the maps lacked the fidelity necessary to determine compliance
with part 420. The FAA intends by this proposal to ensure the scale is
appropriate to the site while still being able to determine compliance.
    Proposed Sec.  420.63(d) would permit a launch site operator to
separate each explosive hazard facility by distances other than those
required by part 420 if the launch site operator could clearly and
convincingly demonstrate a level of safety equivalent to that required
by this part. Section 420.63(c) currently provides that for explosive
siting issues not otherwise addressed by the regulations, a launch site
operator must clearly and convincingly demonstrate a level of safety
equivalent to that otherwise required by part 420. This has meant that
there has been confusion over whether the FAA would permit a
demonstration of an equivalent level of safety for explosive materials
that part 420 already addresses. Proposed paragraph (d) is necessary to
clarify that the FAA intended to permit alternative means of
demonstrating an equivalent level of safety to what part 420 addressed
as well as to what part 420 did not address. In the discussion
accompanying the rulemaking promulgating part 420, the FAA noted that
it would allow alternatives to the quantity-distance (Q-D) requirements
in the form of, for example, hardening of structures or barricades, if
the launch site operator demonstrated that such an approach clearly and
convincingly provided an equivalent level of safety. See Launch Site
Rule, 65 FR at 62821; Licensing and Safety Requirements for Operation
of a Launch Site; Proposed Rule, (Launch Site NPRM), 64 FR 34316, 34322
(Jun. 25, 1999). However, as finally codified, Sec.  420.63(c) states
only that it applies to explosive siting issues not otherwise addressed
by the requirements of part 420. Thus, allowing a launch site operator,
under proposed paragraph (d), to demonstrate an equivalent level of
safety for any explosive siting requirement of part 420 would resolve
the apparent discrepancies between the explanatory preamble and Sec.
420.63(c).

III. Proposed Sec.  420.66 and Storage of Energetic Liquids That Are
Otherwise Regulated and Are Isolated From Each Other

A. Energetic Liquids That Would Not Be Subject to FAA Regulation for
Storage
    Section 420.67 addresses both storing and handling of energetic
liquids. This is confusing and the FAA proposes to separate storing and
handling into two separate sections, relying on proposed Sec.  420.66
for storing and Sec.  420.67 for the handling of energetic liquids. The
FAA proposes to reduce its requirements for appropriate separation
distances to address only the highly hazardous energetic liquids. The
FAA would dispense with separation distance requirements for the
storing of liquid oxidizers and RP-1 when they are sufficiently
isolated from each other that a mishap associated with one material
would not affect the other. This means the FAA would no longer impose
separation requirements for RP-1 or for the oxidizers, liquid oxygen,
nitrogen tetroxide, and hydrogen peroxide in concentrations below 91
percent. These energetic liquids are all currently governed by Sec.
420.67(b) and tables E-3 through E-6 of Appendix E of this part.
    The FAA bases this proposal on two factors: first, when isolated
from incompatible materials, energetic liquids such as liquid oxygen
and RP-1 do not pose a threat of chemical explosion due to accidental
mixing, and, second, other federal and local requirements address fire
prevention for most industrial chemicals. There are situations where
these energetic liquids may contribute to the risks associated with
explosions, and the FAA will continue to regulate them in that context
under Sec.  420.63(c).
    For example, part 420 treats liquid oxygen as an explosive hazard
because, when combined with incompatible materials, chemical explosion
may occur. However, when stored as required by intraline distance
requirements with appropriate mitigation measures to prevent contact
with incompatible materials, such an effect should not result. The FAA
proposes to reclassify liquid oxygen because current separation
requirements always treat liquid oxygen as an explosive hazard, even
when stored in the appropriate intraline distance away from the
incompatible materials.
    When the FAA promulgated part 420, it focused almost entirely on
safety measures for expendable launch vehicles, including the safety
issues surrounding storing and handling of energetic liquids, such as
liquid propellants. The FAA modeled its separation requirements for
table E-3's Hazard Groups I through III liquid propellants on the
requirements employed at the federal launch ranges, where the majority
of FAA licensed launches took place. Accordingly, the FAA followed the
1997 DOD Standard. Consequently, the FAA did not take into account the
pervasive use by federal, state and local jurisdictions of requirements
that address the storage of these classes of materials. Nor did the
commercial space regulations account for the airport requirements
governing fuels. See e.g., 14 CFR 139.321

(requiring each certificate holder to establish standards for
protecting against fire and explosion in storing, dispensing and
otherwise handling fuel on an airport); Aircraft Fuel Storage,
Handling, and Dispensing on Airports, Advisory Circular (AC) No. 150/
5230-4A (Jun. 18, 2004) (2004 AC for Aircraft Fuel). This 2004 AC for
Aircraft Fuel accepts NFPA 407, Standard for Aircraft Fuel Servicing,
as it pertains to fire safety in the safe storage, handling, and
dispensing, of fuels used in aircraft on airports certificated under 14
CFR part 139. The federal Occupational Safety and Health Administration
(OSHA) regulates the storing and handling of energetic liquids to
provide for worker safety. OSHA provides procedural and design
requirements for the materials at issue. See 29 CFR 1910.101, 1910.104,
1910.106 and 1910.119. OSHA regulates RP-1 under 29 CFR 1910.106 with
separation distance, procedural, and design requirements, as well as
with OSHA process safety management requirements for more than 10,000
pounds of RP-1 under 29 CFR 1910.119(a)(1)(ii). OSHA also regulates any
quantity of liquid oxygen that is stored in ``cylinders, portable
tanks, rail tankcars or motor vehicle cargo tanks'' by incorporating
Compressed Gas Association (CGA) Pamphlet P-1 (1965) by reference in 29
CFR 1910.101(b). OSHA regulations for liquid oxygen address design,
operational, and separation distance requirements. See 29 CFR 1910.104.
For stationary tanks, OSHA regulates storage of liquid oxygen in
quantities in excess of 13,000 cubic feet for a connected system or
more than 25,000 cubic feet for an unconnected system at a normal
temperature and pressure. 29 CFR 1910.104(b)(1). OSHA process safety
management requirements apply to storage of more than 7500 pounds of
hydrogen peroxide that is more than 52 percent concentration by weight
or more than 250 pounds of nitrogen tetroxide. 29 CFR 1910.119 App A.
The process safety management requirements include design and
operational procedure requirements, but do not impose explicit
separation requirements. The employer must guarantee the mechanical
integrity of the system, including the pressure vessels and storage
tanks, piping systems, emergency shutdown systems, controls, and pumps.
29 CFR 1910.119(j). In the initial construction, the employer must
ensure these systems are adequate for their functions and must maintain
the components. 29 CFR 1910.119(j)(6). To some extent, the OSHA
requirements protect the public as an ancillary benefit. See 29 CFR
1910.5(d) (clarifying that although a standard may on its face protect
persons who are not employees, the standard only applies in the
employment context).
    Additionally, state and local codes use standards devised by
organizations, such as the CGA, the International Code Council, the
International Fire Code Institute, and NFPA. Several states where
launch sites are located implement some form of the requirements
recommended by these organizations. The exceptions are California,
Florida and Texas.
B. Historical Background
    The issue of overlapping requirements was first brought to light by
the FAA's experience in regulating the East Kern Airport District
(EKAD), the launch site operator of Mojave Air and Space Port. Before
Mojave acquired launch customers, it operated as an airport.
Consequently, it followed the FAA airport and local fire codes,
including the requirements of NFPA. With the advent of reusable launch
vehicles, EKAD confronted a host of siting issues, including the
storing and handling of liquid oxygen, kerosene, and isopropyl alcohol.
    In 2004, the FAA waived EKAD's compliance with Sec.  420.67, which
governs the storage and handling of liquid propellants, including
liquid oxygen and kerosene, and permitted EKAD to comply with DOD
6055.9-STD instead. Commercial Space Transportation; Waiver of Liquid
Propellant Storage and Handling Requirements for Operation of a Launch
Site at the Mojave Airport in California, 69 FR 41327 (Jul. 8, 2004)
(Waiver to Section 420.67 or Waiver Notice). As conditions for granting
a waiver, the FAA required EKAD to follow positive measures used by
OSHA and the NFPA for spill containment and control for isolated
storage of energetic liquids. Id. at 41328, par. F. The FAA also
required using OSHA or NFPA guidance referenced in the DDESB
requirements for storing and handling conventional flammable energetic
liquids and liquid oxidizers, where no significant blast and fragment
hazards were expected. Id. Minimum blast and fragment distances apply,
according to DOD 6055.9-STD, C<IP_ADDRESS>, to NFPA and OSHA Class I-III
flammable and combustible liquids and to conventional oxidizers such as
liquid oxygen.
    In December 2007, in response to EKAD's request, the FAA again
waived explosive siting storage requirements for EKAD by issuing new
license terms and conditions. This time, the FAA stated that, for the
storage of liquid oxygen, kerosene and isopropyl alcohol, EKAD had to
comply with NFPA Standard No. 55 (2005 ed.) and No. 33 (2008 ed.) for
separation distances and spill containment. EKAD License Order No. LSO
04-009A (Rev. 1) (Dec. 20, 2007).
    Recently, the FAA waived storage requirements of part 420 for
liquid oxygen and RP-1 for the Jacksonville Aviation Authority (JAA)
for its operation of portions of Cecil Field as a launch site. JAA,
License Order No. LSO 09-012 (Jan. 11, 2010). In its evaluation of the
request for a waiver, the FAA noted that DDESB adopted NFPA standards
for storing conventional liquid fuels and oxidizers such as liquid
oxygen and RP-1. DoD 6055.9-STD (2004). A review of the accident and
test data of a number of fuels, oxidizers, and monopropellants against
NFPA Hazard Instability Rating system defined by NFPA 704 (1996)
Standard System for the Identification of the Hazards of Materials for
Emergency Response, led DDESB to consider alternative standards for
storing liquid propellants, such as liquid oxygen and RP-1. DDESB
concluded that the main hazard associated with hydrocarbon fuels such
as RP-1 is fire. This means that when it is not co-located with an
oxidizer, RP-1 does not pose a threat of a chemical explosion due to
accidental mixing with that oxidizer. DDESB also considered an NFPA
standard for liquid oxygen based on the NFPA 704 Standard for the
Identification of the Fire Hazards of Materials for Emergency Response
(1996). Although liquid oxygen is a strong oxidizer and may create a
serious fire hazard when combined with combustible materials, liquid
oxygen is not flammable when separated and on its own. Accordingly,
DDESB found that even an unlimited quantity of liquid oxygen need only
maintain a distance of 100 feet between the location of its storage and
incompatible energetic liquids, and 50 feet to compatible energetic
liquids. In this context, liquid oxygen and RP-1, on their own, did not
pose an explosive hazard. Hence, JAA's deviation from the separation
standards of tables E-4 and E-5 of appendix E, for liquid oxygen and
RP-1 did not jeopardize public safety. The FAA granted the waiver.
C. Reasons for Proposed Changes
    The FAA has a number of reasons for proposing to dispense with
separation distance requirements for storing liquid oxygen, nitrogen
tetroxide, hydrogen peroxide in concentrations equal to or below 91
percent and RP-1. These energetic materials do not create explosive
hazards when in isolation,

that is, when not co-located on a launch vehicle as liquid propellants.
Additionally, the FAA does not want its launch separation requirements
to conflict with other federal requirements, which are more
comprehensive in that they contain design and operational requirements
as well as separation requirements. Achieving safety is more
complicated than merely having adequate separation distances. As has
long been the case, safety can be achieved by a combination of
separation distances, safety design, operational control requirements,
hazard communication, or other mechanism, such as process safety
management, so that the risk of a catastrophic incident associated with
storing and handling of hazardous materials occurring may be kept to a
minimum. As discussed above, OSHA and the FAA's own requirements for
airports under 14 CFR part 139 address many of the fire hazards of
these energetic materials through these means. The states, as well,
impose requirements. The FAA's history of issuing waivers demonstrates
that its own separation requirements are not necessary for achieving
safety.
    The FAA's waivers were based on DDESB standards, which are now
incorporating the NFPA standards. DDESB standards themselves do not
apply to civilian commercial activities. Nonetheless, the federal
regulations that do apply adequately address the FAA's concerns.
D. Proposed Change to Classification System
    Part 420, Appendix E, table E-3, currently classifies by hazard
group, the following energetic liquids: hydrogen peroxide, hydrazine,
liquid hydrogen, liquid oxygen, nitrogen tetroxide, RP-1, unsymmetrical
dimethylhydrazine (UDMH) and the combination of UDMH and hydrazine.
Each group represents different levels of hazard. Group I, which
consists of nitrogen tetroxide and RP-1, is a fire hazard. Group II,
which consists of hydrogen peroxide and liquid oxygen, is a group of
strong oxidizers that may exhibit vigorous oxidation or rapid
combustion in contact with materials, such as organic matter, possibly
resulting in serious fires. Group III, which consists of hydrazine,
liquid hydrogen, UDMH, and the combination of hydrazine and UDMH,
presents hazards from the pressure rupture of a storage container
resulting in fire, deflagration, or vapor phase explosions. Either
pressure rupture of a container or vapor phase explosion can cause a
fragment hazard from the container and any protective structure. In
accordance with the current DDESB and NFPA practice, the FAA proposes
to dispense with these hazard groups because the more commonly used
classification system is that of the NFPA. The NFPA classifies
energetic liquids based on instability ratings, as noted above in
section III B.

IV. Separation Distance Requirements for Handling of Division 1.1 and
1.3 Explosives Under Sec.  420.65

    The FAA proposes clarifying changes to its requirements for the
separation distances for handling divisions 1.1 and 1.3 explosives
under Sec.  420.65 and accompanying tables E-1 through E-4 of appendix
E of this part. The FAA proposes to make editorial changes, abandon the
use of linear interpolation, provide more increments for the quantities
in its tables, and provide formulas for calculating acceptable
distances between explosive hazard facilities. The FAA proposes a
number of editorial and organizational changes to improve clarity. The
FAA would no longer refer to the solid explosives governed by this
section as solid propellants because, technically, the provision
applies to more than just solid propellants. Currently, Sec.  420.65
states that it applies to solid propellants, which are used in
expendable launch vehicles (ELVs) for propulsion. Solid propellants are
division 1.3 explosives. Explosives used in an ELV's flight termination
system are division 1.1 explosives. Strictly speaking, the latter are
not propellants, so the FAA proposes the title and the language of this
section more precisely identify what it governs to avoid
misunderstanding.
    The FAA proposes to no longer permit the use of linear
interpolation under Sec.  420.65(d)(4) for any quantities because it
was incorrect for divisions 1.1 and 1.3 explosives and, given the
requirements of the provision, it is unclear when it applies. The lack
of clarity is evident from the fact that, on the one hand, this section
allows a launch site operator to use linear interpolation for the net
explosive weight (NEW) quantities between entries in table E-1. On the
other hand, the table itself either rigidly provides a distance of
1,250 feet for all NEW quantities of 30,000 pounds or less,\3\ or it
provides exponential formulas to calculate distances for quantities in
excess of 30,000 pounds, thus apparently ruling out the use of linear
interpolation for quantities of explosives above and below 30,000
pounds. This makes it unclear when to employ linear interpolation.
Because the relationship between quantity and distance is, in fact,
exponential rather than linear, the use of linear interpolation is
incorrect, even if it were clear where it applied.
---------------------------------------------------------------------------

    \3\ Table E-1 uses a dotted line rather than repeating the
distance of 1,250 feet. The FAA has been applying this to mean that
any quantity below 30,000 pounds has a separation distance of 1,250
feet.
---------------------------------------------------------------------------

    The FAA would also reorganize the tables that accompany this
section for purposes of greater clarity. Currently, appendix E contains
a single table, table E-1, for public area and intraline distances for
divisions 1.1 and 1.3 explosives. The table identifies quantities in
increments starting with zero to 1,000 pounds, and progresses through
quantities between 1,000 and 5,000 pounds, and then advances in
increments of 10,000 and 100,000 pounds up to 1,000,000 pounds.
    The FAA proposes that table E-1 show the minimum separation
distances to public areas and public traffic routes for quantities of
division 1.1 explosives with a NEW for quantities less than or equal to
450 pounds. Currently, the minimum distance from an explosive hazard
facility to a public area for quantities between zero and 30,000 pounds
is 1,250 feet, regardless of whether the quantity is, for example, two
pounds or 9,000 pounds. This greater level of precision would provide
launch site operators greater flexibility while still maintaining
appropriate distances to public areas and public traffic routes. The
FAA would also provide formulas to calculate distances for quantities
that fall between the entries in the table. The formulas would account
for NEW of less than 100 pounds and for quantities between 100 and 450
pounds:

------------------------------------------------------------------------

------------------------------------------------------------------------
NEW <= 0.5 lbs:                       d = 236.
0.5 lbs < NEW < 100 lbs:              d = 291.3 + [79.2 x ln(NEW)].
100 lbs <= NEW <= 450 lbs:            d = - 1133.9 + [389 x ln(NEW)].
------------------------------------------------------------------------

Where NEW is in pounds; d is distance in feet, and ln is natural
logarithm.
    The FAA has allowed licensees to demonstrate an equivalent level of
safety by using the formulas proposed here. The formulas account for
the fact that fragments are the primary hazard associated with division
1.1 explosives for quantities of 450 pounds or less. Air blast can
carry or propel fragments, but it is the fragments that cause the
damage to persons. The proposed formula in table E-1 would account for
the probability that one hazardous fragment would land within a 600
square feet area for a given quantity of division 1.1 explosive. The
relationship is a natural logarithmic function when calculating
distance based on NEW. When

calculating permissible NEW from distance, the inverse function of the
natural logarithmic function, or the exponential function, is used.
    The relationship is based on data obtained from DDESB TP 16, rev.
2, 2005 Methodologies for Calculating Primary Fragment Characteristics.
DDESB conducted tests that accounted for hazardous debris fragments
based on a fragment that would cause a fatality, namely, one with a
kinetic energy at impact of 58 foot-pounds. A kinetic energy of 58
foot-pounds equates to a one percent probability of a person
approximately six feet tall and one foot wide being struck by that
fragment at a given separation distance from a given NEW. For
quantities between 450 and 30,000 pounds, the minimum separation
distance of 1,250 feet remains unchanged. For quantities of 30,000
pounds or more, the hazards include blast, fragments, and debris. When
public areas are protected from blast effect by a separation distance
between 40 NEW1/3 and 50 NEW1/3, persons in the
open are not expected to experience serious injuries arising out of
blast effects. DoD Standard 6055.9--STD C<IP_ADDRESS>.3 (2004). The FAA does
not propose to change the methodology for calculating separation
distances for quantities greater than 30,000 pounds.
    Table E-2 would also contain the public traffic route distances for
division 1.1 explosives. In Sec.  420.65(d)(3), the FAA already permits
a launch site operator to employ the more lenient public traffic route
separation distance, but only for division 1.1 explosives. Although a
public traffic route is a public area, this section permits a
separation distance of 60 percent of the public area distance. Thus,
for convenience, proposed table E-2 would show the distance currently
permitted by Sec.  420.65(d)(3).
    Table E-2 would also contain a formula by which a launch site
operator could determine the maximum NEW it could handle in an
explosive hazard facility as would be permitted by the proposed Sec.
420.65(e)(3). The proposed formulas reflect the inverse function of the
equations provided by current table E-1. Publishing them would allow a
launch site operator to calculate the maximum quantities it could have
in an existing explosive hazard facility based on distances. This will
increase the flexibility of launch site operators who already have
constructed sites, but wish to expand their operations into serving as
launch sites.
    Proposed table E-3 would contain intraline distance formulas
currently contained in table E-1 for division 1.1 solid explosives. For
division 1.1 explosives, the FAA would decrease the increments between
quantities for greater convenience. Also, the proposed table would
provide a formula for calculating separation distances for quantities
that fall between table entries.
    For division 1.3 explosives, proposed table E-4 would contain
minimum separation distances to public areas and public traffic routes,
and intraline distances. The distances the FAA proposes reflect the
exponential relationship, between the quantity of division 1.3
explosives and the necessary separation distances, rather than the
inaccurate linear interpolation relationship currently expressed in the
rules. Accordingly, the distances would be smaller than those currently
required by table E-1.
    Proposed Sec.  420.65(d)(3) would require a launch site operator to
separate each public area containing any member of the public in the
open by a distance equal to -1133.9 + [389 * ln(NEW)] where the NEW is
greater than 450 pounds and less than 600,000 pounds. Under current
part 420, the FAA does not distinguish between public areas that are
buildings, where people are sheltered, and those where people are out
in the open. For a net explosive weight up to 30,000 pounds, fragments
rather than blast can injure people in the open. DoD Standard 6055.9--
STD C<IP_ADDRESS>.3 (2004). Even at 1,250 feet, the distance mandated by
current Sec.  420.65(c) and (d) and current table E-1, a person may be
injured by fragments. Id. This proposed formula also applies to liquid
propellants where explosive equivalent weights apply so that a launch
site operator may employ proposed table E-2. This will result in
greater distances for some public areas than are required under current
rules, but should not result in increased distances for siting
buildings. The proposed requirement would impose a constraint on
operations more than on siting facilities.
    This new requirement would not affect the siting of facilities in
relationship to public traffic routes such as roads. The facility could
still be sited at sixty percent of the distance to a public area.
However, if there were people in the open on a public road during an
operation involving division 1.1 explosives or liquid propellants, the
members of the public would have to be kept at the distance mandated by
the formula. Depending on the net explosive weight, the distance could
be less than or greater than the public area or public traffic route
distances. The FAA does not consider persons in moving vehicles to be
in the open.
    The FAA also proposes to permit launch site operators to determine
permissible NEW or TNT equivalent weight for existing facilities under
proposed paragraph (e). Not all launch sites are built from the ground
up. As experience over the past few years demonstrates, airports may
apply for a license to operate a launch site. On occasion, the operator
will want to use existing facilities for handling of division 1.1
explosives or liquid propellants. The FAA would provide a formula for
the operator to calculate the maximum quantity permitted. The formula
provided in table E-1 is based on fragment hazard tests that DDESB
conducted, which can be found in DDESB TP 16, rev. 2. The formula
provided in table E-2 is based on current table E-1 for blast
overpressure equations. The operator would have to measure the distance
from the explosive hazard facility using the measuring requirements of
proposed Sec.  420.70.

V. Separation Distance Requirements for Storage of Hydrogen Peroxide,
Hydrazine, and Liquid Hydrogen and Any Energetic Liquids Incompatible
With and Stored Within an Intraline Distance of Any of Them

    Through proposed Sec.  420.66, the FAA will continue to impose
storage requirements for hydrazine, liquid hydrogen, and hydrogen
peroxide in concentrations of greater than 91 percent because of
concerns regarding a greater risk for a chemical explosion associated
with these energetic liquids, but will not address quantities below 100
pounds for liquid hydrogen and hydrazine. Under current requirements,
table E-3 shows that all three of these energetic liquids belong to
Hazard Group III, which means that table E-4 applies. Under the
proposed requirements, the distances would not change in proposed table
E-8. The FAA recognizes that OSHA addresses liquid hydrogen and
hydrazine, but the FAA is not going to rely on OSHA for quantities of
liquid hydrogen above 100 pounds because OSHA requires no more than 100
feet for outdoor storage of quantities up to 30,000 gallons. Part 420
separation distances vary depending on quantity. Likewise, OSHA
addresses hydrazine, but the separation distances for quantities in
excess of 100 pounds remain of concern to the FAA for public safety
purposes in that they pose a threat of catastrophic consequences. Even
in storage, accidents can happen with these materials. NFPA standards,
which are incorporated by other regulators as discussed above, address
the storage of hydrogen peroxide in high concentrations, but the FAA
will keep

its requirements for this energetic liquid. The NFPA standards are
silent regarding separation distances for quantities above 10,000
pounds.
    The FAA proposes to create a new Sec.  420.66 to govern the storage
of these materials for greater clarity. Current Sec.  420.67, which
governs the storage and handling of liquid propellants, already
contains most of these requirements. The FAA proposes to relocate the
rules governing measurement to proposed Sec.  420.70.
    Proposed Sec.  420.66 would apply to hydrogen peroxide in
concentrations of greater than 91 percent, hydrazine, liquid hydrogen,
or any energetic liquid that is incompatible with and is stored within
an intraline distance of any of them. As with the current requirements,
a launch site operator would first determine the total quantity of
energetic liquids it would store on its launch site. As with the
current rule, a launch site operator must convert each of the energetic
liquid's quantity from gallons to pounds. The formula would remain
unchanged, but we propose to add, in proposed table E-6, conversion
factors for additional energetic liquids not currently addressed by
table E-3 of the current rule. The FAA obtained the conversion factors
for ethyl alcohol,\4\ and red fuming nitric acid from the 2004 DDESB
standard. The FAA will continue to require that a launch site operator
determine distances for compatible energetic liquids in the same manner
as the current rule, but would increase flexibility in siting with
respect to those public areas that are public traffic routes. For co-
located incompatible energetic liquids where explosive equivalents
apply, under proposed Sec.  420.67(c)(2), the FAA proposes to permit
using a public traffic route distance for incompatible energetic
liquids that are within an intraline distance of each other. This would
provide incompatible energetic liquids the same treatment accorded to
division 1.1 solid explosives. Section 420.65(d)(3) permits division
1.1 solid explosives to be separated from public traffic routes by a
distance of 60 percent of the public area distance. In light of the
fact that the explosion of incompatible energetic liquids can be
expressed in an explosive equivalent of division 1.1 explosives, there
appears to be no reason not to offer these energetic liquids the same
opportunity to employ a shorter distance to public traffic routes.
---------------------------------------------------------------------------

    \4\ Although ethyl alcohol and JP-10 are in the family of Class
I-III flammable and combustible liquids, which the FAA proposes to
stop addressing in part 420, if either are within an intraline
distance of the incompatible hydrogen peroxide, separation distances
would apply under proposed Sec.  420.66(a)(4).
---------------------------------------------------------------------------

    Currently, table E-5 prescribes separation distances for hydrogen
peroxide without specifying the concentration levels to which it
applies. Proposed table E-7 would contain separation distances for high
concentrations of hydrogen peroxide (greater than 91 percent) in
quantities above 10,000 pounds. Because the current distances encompass
hydrogen peroxide at lower concentrations, the distances proposed would
be greater than those currently required. This reflects the 2004 DOD
Standard. As noted in the section discussing storage requirements, OSHA
imposes process safety management requirements in quantities greater
than 7500 pounds and in concentrations of greater than 52 percent by
weight.
    Proposed table E-8 would contain the requirements of current table
E-6 for hydrazine and liquid hydrogen. The FAA proposes to dispense
with separation requirements for quantities of liquid hydrogen and
hydrazine of less than 100 pounds because OSHA regulates these
materials in quantities below 100 pounds. OSHA's regulation of liquid
hydrogen includes separation distance, design, and operational
procedure requirements. The requirements apply to storage of all liquid
hydrogen except portable containers of less than 150 liters (39.63
gallons). 29 CFR 1910.103(a)(2)(ii). Requirements for separation
distances may be found at 29 CFR 1910.103(c)(2)(ii)(b). Design
requirements may be found at 29 CFR 1910.103(c)(1) and operational
constraints at 29 CFR 1910.103(c)(4). OSHA regulates hydrazine with
separation distance, design, and operational procedure requirements.
OSHA provides separation distance requirements for outdoor containers
of hydrazine. 29 CFR 1910.106(a)(27), (d)(6)(i) and (d)(6)(ii)(b). OSHA
applies design and testing requirements. 29 CFR 1910.106(b)(7),
1910.106(c)(6), and 1910.106(d)(2)-(5). Operational procedure
requirements may be found at 29 CFR 1910.106(b)(1)(iv)(a),
1910.106(b)(1)(v)(a), and 1910.106(b)(5)(vi). The FAA remains concerned
about and will continue its regulation of the greater quantities
because of their potential for catastrophic events.
    Currently, Sec.  420.67(b) requires a launch site operator to
determine hazard and compatibility groups and separate liquid
propellants from each other and from each public area using the
distances identified in tables E-4 though E-7 of Appendix E of this
part. The only substantive change the FAA now proposes to this
paragraph arises out of the FAA's proposal to dispense with the hazard
compatibility groups of table E-3. As noted in the discussion of the
storage of liquid propellants, the FAA proposes to dispense with
classifying certain liquid propellants as members of Hazard Groups I,
II or III. Currently, table E-3 identifies what hazard group a material
belongs to, and tables E-4, E-5 and E-6 impose separation distances for
each of those hazard groups. These classifications would be unnecessary
because the hazard groups only apply to storage distances, and, once we
focus only on certain energetic liquids, we no longer would require
these broad classifications.

VI. Separation Distances for the Handling of Incompatible Energetic
Liquids That Are Co-Located

    At times, incompatible energetic liquids must be co-located and
even mixed to fulfill their intended functions as liquid propellants.
Most obviously, many launch vehicles' performance come from the
propulsion power provided by liquid bipropellant systems consisting of
a liquid fuel and oxidizer. Engine tests also require the handling of
energetic liquids when in close enough proximity to create a hazard of
an explosion occurring. Once liquid propellants are co-located for
these or other operational purposes, different separation distances to
the public apply than for the storage of energetic liquids. If
incompatible energetic liquids are co-located, the handling distances
of Sec.  420.67 apply for determining intraline and public area
distances. The FAA also notes that although it proposes to dispense
with requirements for NFPA Class I-III flammable and combustible
liquids for storage, it will still require that a launch site operator
account for them when determining separation distances for
combinations.
    Section 420.67 would narrow in scope. Currently, it applies as
written to liquid propellants at a launch site. In practice, this has
meant that when a launch operator is located at an airport,
requirements that were originally intended for launch vehicles and
engine testing applied to jet fuels and other energetic liquids for
which there were already requirements. Section 420.67(a) would limit
its applicability to rocket engines. Specifically, it would apply where
incompatible energetic liquids are co-located in a launch or reentry
vehicle tank or other vessel, such as a propulsion unit, on the
vehicle. This would include such obvious applications as a vehicle on a
launch

pad or runway. It would also include engine firing, for test or other
purposes. In short, Sec.  420.67 would apply to rocket engines at a
launch site because the FAA wishes to confine its launch site
regulations to energetic liquids used for space and not aviation
applications.
    For the reasons provided in the discussion of Sec.  420.65, the FAA
proposes to provide tables and formulas for quantities up to 450 pounds
rather than requiring a distance of 1,250 feet for all quantities up to
30,000 pounds. As clarified in proposed Sec.  420.67(d)(4), which would
clarify and expand upon current Sec.  420.67(b)(5), for explosive
hazard facilities of a single customer, a launch site operator must use
the greater intraline distance to separate the facilities from each
other.\5\ For example, a launch site operator may plan to have a
customer who will use a launch pad and a runway for horizontal take-off
of a launch vehicle. These two explosive hazard facilities need only be
separated by an intraline distance, but it must be the distance that
reflects the larger quantity. Thus, if an expendable launch vehicle at
a launch pad required a distance of 1,250 feet, while a horizontal
take-off vehicle required a distance of only 700 feet, the runway and
the launch pad would have to be located 1,250 feet from each other.
---------------------------------------------------------------------------

    \5\ This reflects the contents of current Sec.
420.67(a)(2)(iii).
---------------------------------------------------------------------------

    Proposed Sec.  420.67(d)(4) would also clarify that for explosive
hazard facilities used by different customers, a launch site operator
must use the greater public area distance to separate the explosive
hazard facilities from each other. This is implicit in the current
requirements because different launch operators are the public with
respect to each other. Section 420.5 defines the public as persons not
involved in supporting a launch, and includes any other launch operator
and its personnel. Accordingly, under the existing rules, if the public
area distance created by launch operator A's vehicle at one launch pad
was 1250 feet and 700 feet for launch operator B's launch pad, the
launch pads would have to be separated by the greater distance of 1,250
feet. An explicit requirement would increase clarity.
    Under proposed Sec.  420.67(c)(2), the FAA would permit a launch
site operator to use the shorter distances of table E-1 for liquid
propellants with explosive equivalencies in quantities below or equal
to 450 pounds. In promulgating part 420, the FAA created table E-1 to
show separation distance requirements for solid explosives. Table E-1
requires a separation distance of 1,250 feet to a public area for
division 1.1 explosives in quantities between zero and 30,000 pounds.
As discussed earlier, the FAA now proposes to achieve a higher level of
fidelity so that for a site where liquid propellants are handled or co-
located more accurate separation distances to public areas would be
available for liquid as well as solid propellants. The FAA recognized
the need for greater fidelity when it waived Sec.  420.67 for XCOR
Aerospace's operations on a runway at Mojave Air and Space Port, where
it was fueling its vehicle with liquid oxygen and kerosene. Although
the XCOR Aerospace waiver applied to the handling of liquid
propellants, table E-1 applied because energetic liquids are translated
into their ``explosive equivalent'' in TNT to determine their
equivalence in explosive yield. As the FAA explained when it first
proposed part 420, if fuels and oxidizers are located within close
enough distances of each other, the distance to the public must account
for the hazardous consequences of their potential combination. See
Launch Site NPRM, 64 FR 34335. The combination is measured in terms of
explosive equivalency, a measure of the blast effects from explosion of
a given quantity of a fuel and oxidizer mixture expressed in terms of
the weight of TNT that would produce the same blast effects when
detonated. Id.

VII. Separation Distance Requirements for Co-Location of Divisions 1.1
and 1.3 Explosives and Liquid Propellants

    For launch vehicles that require strap-on solid rocket motors and
are equipped with flight termination systems, liquid propellants are in
close proximity to class 1.1 or class 1.3 explosives. Section 420.69
applies on those occasions.
    The FAA proposes to revise its requirements for separation
distances for co-located division 1.1 and 1.3 explosives and liquid
propellants. The distances to public areas and public traffic routes
will be shorter to correct the FAA's error in Sec.  420.69(b). Current
Sec.  420.69 requires that a launch site operator determine the
separation distances for solid propellant division 1.1 and 1.3
explosives and then determine the separation distances for a liquid
propellant combination within an intraline distance. Having determined
the separation distance for each, a launch site operator must add the
two separation distances together to achieve a minimum distance to a
public area. For example, if a launch pad contains 20 pounds of
division 1.1 explosives, which generates a public area distance of 529
feet, and liquid oxygen and kerosene with an explosive equivalent of
45,000 pounds, which generates a public area distance of 1,423 feet,
the resulting public area distance under current requirements must be
the sum of the two distances, which is 1,952 feet.
    As the FAA recognized in its discussion of the issue at the time it
promulgated this section, a simultaneous explosion of both the solid
and liquid propellants, although unlikely, is not improbable. Launch
Site Rule, 65 FR 62821. Accordingly, the FAA decided the separation
distance applicable to the liquid propellants had to be added to the
separation distance applicable to the solid propellant under Sec.
420.69(b) and (c). This was a mistake. As with the other approaches to
determining correct separation distances, the weights of the various
propellants, solid and liquid both, are added before determining the
distances. Thus, using the example above, once a launch site operator
determines that the total NEW of the solid propellants is 20 pounds and
the explosive equivalent of the liquid propellants is 45,000 pounds,
the total NEW of 45,020 pounds yields a distance of 1,423 feet rather
than the 1,952 feet of current Sec.  420.69. The proposed methodology
would apply to both division 1.1 and 1.3 explosives.

VIII. Measuring Requirements

    The FAA proposes a new Sec.  420.70 to contain all the measuring
requirements for calculating the distances by which explosive hazard
facilities must be separated from each other and from the public.
Separation distance requirements are currently spread from Sec. Sec.
420.65 through 420.69. Consolidating those requirements into a single
section, Sec.  420.70, would ensure that a launch site operator would
need to look in only one place to find the measuring requirements it
must meet. The majority of these requirements are already in part 420.
They include the requirements for measuring separation distances for
solid propellants, currently located in Sec.  420.65(d)(5), and
energetic liquids, currently located in Sec.  420.67(b)(1). New
measurement requirements would include requiring a launch site operator
to employ straight lines, as would be required by proposed Sec.
420.70(b) measuring from taxiways and runways as required by proposed
Sec.  420.70(c), and measuring to a public traffic route by using its
nearest side as required by proposed Sec.  420.70(c)(2). The FAA is
proposing the new requirements because there has been confusion over
which points to use as starting points for measurements. These
requirements would reduce any such confusion and

ensure the FAA treats all launch site operators' measurements the same.

Paperwork Reduction Act

    The Paperwork Reduction Act of 1995 (44 U.S.C. 3507(d)) requires
that the FAA consider the impact of paperwork and other information
collection burdens imposed on the public. According to the 1995
amendments to the Paperwork Reduction Act (5 CFR 1320.8(b)(2)(vi)), an
agency may not collect or sponsor the collection of information, nor
may it impose an information collection requirement unless it displays
a currently valid Office of Management and Budget (OMB) control number.
    The FAA has determined that there would be no new information
collection associated with the proposed requirement to collect data
required for performing launch site location analysis. Approval to
collect such information previously was approved by the Office of
Management and Budget (OMB) under the provisions of the Paperwork
Reduction Act of 1995 (44 U.S.C. 3507(d)) and was assigned OMB Control
Number 2120-0644.

International Compatibility

    In keeping with U.S. obligations under the Convention on
International Civil Aviation, it is FAA policy to conform to
International Civil Aviation Organization (ICAO) Standards and
Recommended Practices to the maximum extent practicable. This is not an
aviation rulemaking, and the FAA has determined that there are no ICAO
Standards and Recommended Practices that correspond to these proposed
regulations.

Regulatory Evaluation, Regulatory Flexibility Determination,
International Trade Impact Assessment, and Unfunded Mandates Assessment

    Changes to Federal regulations must undergo several economic
analyses. First, Executive Order 12866 directs that each Federal agency
shall propose or adopt a regulation only upon a reasoned determination
the benefits of the intended regulation justify its costs. Second, the
Regulatory Flexibility Act of 1980 (Pub. L. 96-354) requires agencies
to analyze the economic impact of regulatory changes on small entities.
Third, the Trade Agreements Act (Pub. L. 96-39) prohibits agencies from
setting standards that create unnecessary obstacles to the foreign
commerce of the United States. In developing U.S. standards, the Trade
Act requires agencies to consider international standards and, where
appropriate, that they be the basis of U.S. standards. Fourth, the
Unfunded Mandates Reform Act of 1995 (Pub. L. 104-4) requires agencies
to prepare a written assessment of the costs, benefits, and other
effects of proposed or final rules that include a Federal mandate
likely to result in the expenditure by State, local, or tribal
governments, in the aggregate, or by the private sector, of $100
million or more annually (adjusted for inflation with base year of
1995). This portion of the preamble summarizes the FAA's analysis of
the economic impacts of this proposed rule.
    Department of Transportation Order DOT 2100.5 prescribes policies
and procedures for simplification, analysis, and review of regulations.
If the expected cost impact is so minimal that a proposed or final rule
does not warrant a full evaluation, this order permits that a statement
to that effect and the basis for it be included in the preamble if a
full regulatory evaluation of the cost and benefits is not prepared.
Such a determination has been made for this proposed rule. The
reasoning for this determination follows.
    The FAA proposes to dispense with separation distance requirements
for storing liquid oxidizers and Class I, II and III flammable and
combustible liquids because they are unnecessarily conservative as
explained earlier. The FAA proposes to dispense with the hazard groups
of tables E-4 through E-6 of appendix E of part 420 as a means of
classification. This would allow for closer siting of explosives
without degrading safety. Safety would not be degraded because of the
operational controls and design requirements of other standards. In
addition, the FAA proposes to identify the minimum separation distances
to public areas and public traffic routes for quantities between less
than half a pound and 450 pounds of division 1.1 explosives and liquid
propellants with TNT equivalency.
    Because of these changes launch sites might be able to use the
infrastructure of existing airport facilities and, therefore, the
proposed rule would be cost relieving. The proposed rule would also
allow for the development of more launch sites where the more
conservative siting requirements of the current regulation might
constrain their development.
    Certain proposed changes would add clarity to the current
regulations and result in reduced ambiguity and confusion. For
instance, clarifying the meaning of explosive hazard facility to state
that it can be a location as well as a facility avoids the possibility
of misinterpreting the current definition to apply only to buildings or
storage sites. The proposed rule would remove ambiguities over the
labeling of materials to different users of the same material. The rule
would also clarify that the FAA intended to permit alternative means of
demonstrating an equivalent level of safety to what part 420 addressed
as well as to what part 420 did not address. These changes are expected
to be cost neutral.
    The proposed rule would add a requirement to Sec.  420.63 that the
explosive site map be at a scale sufficient to determine compliance
with part 420. The FAA is proposing this to avoid a reiterative process
to obtain a map at an appropriate scale. Situations have arisen where
the FAA has received maps that were difficult to read. As a result,
considerable time was expended determining distances between elements
on the map. In this respect, the proposal can be cost relieving. The
rule could require some operators to redraw existing maps. However, we
expect that with programs like AutoCAD and Geographic Information
System (GIS) software, the cost to change the scale will be minimal. We
don't believe that anyone would be required to redraw an existing map
by hand due to this requirement. The FAA calls for comments regarding
whether this provision will be cost relieving, and if not, provide
sufficient documentation such that we can provide an accurate cost
estimate.
    Under current part 420, the FAA does not distinguish between public
areas that are buildings, where people are sheltered, and those where
people are out in the open. This proposal would result in greater
distances for some public areas than are required under current rules,
but should not result in increased distances for siting buildings. The
operational constraints themselves should not increase costs because a
launch site operator currently must ensure under Sec.  420.55 that its
customers schedule their hazardous operations so as not to harm members
of the public. A site operator may incur minimal costs in performing
these new calculations and updating its procedures to reflect any
changes in distances. The FAA calls for comments on whether this new
requirement will impose costs.
    By dispensing with the current separation distance requirements for
certain energetic liquids and reducing separation distance requirements
for divisions 1.1 and 1.3 explosives and liquid propellants the rule
would be cost relieving. The FAA proposes this 1) for energetic liquids
that are fire hazards rather than explosive hazards because when
sufficiently isolated from each other, these liquids do not pose a

chemical explosion hazard; and 2) for liquids that are already
addressed by other federal requirements.
    Because this proposed rule would relieve launch sites from storage
requirements for most energetic liquids and reduce the separation
distances requirements for divisions 1.1 and 1.3 explosives and liquid
propellants, the expected outcome would be reduced cost. The possible
benefits would be the proposal might encourage the development of more
launch sites. By encouraging existing launch sites to more effectively
use their infrastructure and by allowing colocation of launch sites
with some existing airports, the proposed rule would provide benefits
and be cost relieving. There might also be cost savings if the FAA
issues fewer waivers as a result of this rule.
    The FAA has, therefore, determined this proposed rule is not a
``significant regulatory action'' as defined in section 3(f) of
Executive Order 12866, and is not ``significant'' as defined in DOT's
Regulatory Policies and Procedures.

Regulatory Flexibility Determination

    The Regulatory Flexibility Act of 1980 (Pub. L. 96-354) (RFA)
establishes ``as a principle of regulatory issuance that agencies shall
endeavor, consistent with the objectives of the rule and of applicable
statutes, to fit regulatory and informational requirements to the scale
of the businesses, organizations, and governmental jurisdictions
subject to regulation. To achieve this principle, agencies are required
to solicit and consider flexible regulatory proposals and to explain
the rationale for their actions to assure that such proposals are given
serious consideration.'' The RFA covers a wide-range of small entities,
including small businesses, not-for-profit organizations, and small
governmental jurisdictions.
    Agencies must perform a review to determine whether a rule will
have a significant economic impact on a substantial number of small
entities. If the agency determines that it will, the agency must
prepare a regulatory flexibility analysis as described in the RFA.
    However, if an agency determines that a rule is not expected to
have a significant economic impact on a substantial number of small
entities, section 605(b) of the RFA provides that the head of the
agency may so certify and a regulatory flexibility analysis is not
required. The certification must include a statement providing the
factual basis for this determination, and the reasoning should be
clear.
    The proposed rule does not impose costs on industry because it
provides options to launch sites with regards to explosive siting but
does not require launch site operators to increase the distances around
where they have sited explosives and because other requirements are
consistent with industry practice. Consequently, the FAA certifies that
the rule will not have a significant economic impact on a substantial
number of small entities.

Trade Impact Assessment

    The Trade Agreements Act of 1979 (Pub. L. 96-39), as amended by the
Uruguay Round Agreements Act (Pub. L. 103-465), prohibits Federal
agencies from establishing standards or engaging in related activities
that create unnecessary obstacles to the foreign commerce of the United
States. Pursuant to these Acts, the establishment of standards is not
considered an unnecessary obstacle to the foreign commerce of the
United States, so long as the standard has a legitimate domestic
objective, such the protection of safety, and does not operate in a
manner that excludes imports that meet this objective. The statute also
requires consideration of international standards and, where
appropriate, that they be the basis for U.S. standards. This rule would
have only a domestic impact.

Unfunded Mandates Assessment

    Title II of the Unfunded Mandates Reform Act of 1995 (Pub. L. 104-
4) requires each Federal agency to prepare a written statement
assessing the effects of any Federal mandate in a proposed or final
agency rule that may result in an expenditure of $100 million or more
(in 1995 dollars) in any one year by State, local, and tribal
governments, in the aggregate, or by the private sector; such a mandate
is deemed to be a ``significant regulatory action.'' The FAA currently
uses an inflation-adjusted value of $143.1 million in lieu of $100
million.
    This proposed rule does not contain such a mandate; therefore the
requirements of Title II do not apply.

Executive Order 13132, Federalism

    The FAA has analyzed this proposed rule under the principles and
criteria of Executive Order 13132, Federalism. We determined that this
action would not have a substantial direct effect on the States, on the
relationship between the national Government and the States, or on the
distribution of power and responsibilities among the various levels of
government, and, therefore, would not have federalism implications.

Environmental Analysis

    FAA Order 1050.1E identifies FAA actions that are categorically
excluded from preparation of an environmental assessment or
environmental impact statement under the National Environmental Policy
Act in the absence of extraordinary circumstances. The FAA has
determined this proposed rulemaking action qualifies for the
categorical exclusion identified in paragraph 310f and involves no
extraordinary circumstances.

Regulations That Significantly Affect Energy Supply, Distribution, or
Use

    The FAA has analyzed this NPRM under Executive Order 13211, Actions
Concerning Regulations that Significantly Affect Energy Supply,
Distribution, or Use (May 18, 2001). We have determined that it is not
a ``significant energy action'' under the executive order, because it
is not a ``significant regulatory action'' under Executive Order 12866
and DOT's Regulatory Policies and Procedures, and it is not likely to
have a significant adverse effect on the supply, distribution, or use
of energy.

Additional Information

Comments Invited

    The FAA invites interested persons to participate in this
rulemaking by submitting written comments, data, or views. We also
invite comments relating to the economic, environmental, energy, or
federalism impacts that might result from adopting the proposals in
this document. The most helpful comments reference a specific portion
of the proposal, explain the reason for any recommended change, and
include supporting data. To ensure the docket does not contain
duplicate comments, please send only one copy of written comments, or
if you are filing comments electronically, please submit your comments
only one time.
    We will file in the docket all comments we receive, as well as a
report summarizing each substantive public contact with FAA personnel
concerning this proposed rulemaking. Before acting on this proposal, we
will consider all comments we receive on or before the closing date for
comments. We will consider comments filed after the comment period has
closed if it is possible to do so without incurring expense or delay.
We may change this proposal in light of the comments we receive.

Proprietary or Confidential Business Information

    Do not file in the docket information that you consider to be
proprietary or confidential business information. Send or deliver this
information directly to the person identified in the FOR FURTHER
INFORMATION CONTACT section of this document. You must mark the
information that you consider proprietary or confidential. If you send
the information on a disk or CD ROM, mark the outside of the disk or CD
ROM and also identify electronically within the disk or CD ROM the
specific information that is proprietary or confidential.
    Under 14 CFR 11.35(b), when we are aware of proprietary information
filed with a comment, we do not place it in the docket. We hold it in a
separate file to which the public does not have access, and we place a
note in the docket that we have received it. If we receive a request to
examine or copy this information, we treat it as any other request
under the Freedom of Information Act (5 U.S.C. 552). We process such a
request under the DOT procedures found in 49 CFR part 7.

Availability of Rulemaking Documents

    You can get an electronic copy of rulemaking documents using the
Internet by--
    1. Searching the Federal eRulemaking Portal (http://www.regulations.gov);
    2. Visiting the FAA's Regulations and Policies web page at http://www.faa.gov/regulations_policies or
    3. Accessing the Government Printing Office's web page at http://www.gpoaccess.gov/fr/index.html.
    You can also get a copy by sending a request to the Federal
Aviation Administration, Office of Rulemaking, ARM-1, 800 Independence
Avenue, SW., Washington, DC 20591, or by calling<PHONE_NUMBER>. Make
sure to identify the docket or notice number of this rulemaking.
    You may access all documents the FAA considered in developing this
proposed rule, including economic analyses and technical reports, from
the internet through the Federal eRulemaking Portal referenced in
paragraph (1).

List of Subjects in 14 CFR Part 420

    Environmental protection, Reporting and recordkeeping requirements,
Space transportation and exploration.

The Proposed Amendment

    In consideration of the foregoing, the Federal Aviation
Administration proposes to amend Chapter III of Title 14, Code of
Federal Regulations, as follows:

PART 420--LICENSE TO OPERATE A LAUNCH SITE

    1. The authority citation for part 420 continues to read as
follows:

    Authority: 49 U.S.C. 70101-70121.

    2. Amend Sec.  420.5 by revising the definition of Explosive hazard
facility and by adding the definitions of Energetic liquid, Liquid
propellant, Maximum credible event, and Public traffic route, in
alphabetical order to read as follows:

Sec.  420.5  Definitions.

* * * * *
    Energetic liquid means a liquid, slurry, or gel, consisting of, or
containing an explosive, oxidizer, fuel, or combination of the above,
that may undergo, contribute to, or cause rapid exothermic
decomposition, deflagration, or detonation.
* * * * *
    Explosive hazard facility means a facility or location at a launch
site where solid explosives, energetic liquids, or other explosives are
stored or handled.
* * * * *
    Liquid propellant means a monopropellant or incompatible energetic
liquids co-located for purposes of serving as propellants on a launch
vehicle or a related device.
    Maximum credible event means a hypothesized worst-case accidental
explosion, fire, or agent release that is likely to occur from a given
quantity and disposition of explosives, chemical agents, or reactive
material.
* * * * *
    Public traffic route means any public highway or railroad that the
general public may use.
* * * * *
    3. Revise Sec.  420.63 to read as follows:

Sec.  420.63  Explosive siting.

    (a) Except as otherwise provided by paragraph (b) of this section,
a licensee must ensure the configuration of the launch site follows its
explosive site plan, and the licensee's explosive site plan complies
with the requirements of Sec. Sec.  420.65 through 420.70. The
explosive site plan shall include:
    (1) A scaled map that shows the location of all explosive hazard
facilities at the launch site and that shows actual and minimal
allowable distances between each explosive hazard facility and all
other explosive hazard facilities, each public area, including the
launch site boundary and any public traffic route;
    (2) A list of the maximum quantity of energetic liquids, solid
propellants and other explosives to be located at each explosive hazard
facility, including the class and division for each solid;
    (3) A description of each activity to be conducted in each
explosive hazard facility; and
    (4) An explosive site map using a scale sufficient to show whether
distances and structural relationships satisfy the requirements of this
part.
    (b) A licensee operating a launch site located on a federal launch
range does not have to comply with the requirements in Sec. Sec.
420.65 through 420.70 if the licensee complies with the federal launch
range's explosive safety requirements.
    (c) For explosive siting issues not addressed by the requirements
of Sec. Sec.  420.65 through 420.70, a launch site operator must
clearly and convincingly demonstrate a level of safety equivalent to
that otherwise required by this part.
    (d) A launch site operator may separate an explosive hazard
facility from another explosive hazard facility or a public area by a
distance different from one required by this part only if the launch
site operator clearly and convincingly demonstrates a level of safety
equivalent to that required by this part.
    4. Revise Sec.  420.65 to read as follows:

Sec.  420.65  Separation distance requirements for handling division
1.1 and 1.3 explosives.

    (a) A launch site operator must determine the maximum total
quantity of division 1.1 and 1.3 explosives by class and division, in
accordance with 49 CFR part 173, Subpart C, to be located in each
explosive hazard facility where division 1.1 and 1.3 explosives will be
handled.
    (b) When division 1.1 and 1.3 explosives are located in the same
explosive hazard facility, the total quantity of explosive must be
treated as division 1.1 for determining separations distances; or, a
launch site operator may add the net explosive equivalent weight of the
division 1.3 items to the net weight of division 1.1 items to determine
the total quantity of explosives.
    (c) A launch site operator must separate each explosive hazard
facility where division 1.1 and 1.3 explosives are handled from all
other explosive hazard facilities, all public traffic routes, each
public area, including the launch site boundary, by a distance no less
than that provided for each quantity and explosive division in appendix
E of this part as follows:
    (1) For division 1.1 explosives, the launch site operator must use
tables

E-1, E-2, and E-3 of appendix E of this part to determine the distance
to each public area and public traffic route and each intraline
distance.
    (2) For division 1.3 explosives, the launch site operator must use
table E-4 of appendix E of this part to determine the distance to each
public area, public traffic route, and intraline distance.
    (d) A launch site operator must:
    (1) Employ no less than the applicable public area distance to
separate an explosive hazard facility from each public area, including
the launch site boundary.
    (2) Employ no less than an intraline distance to separate an
explosive hazard facility from all other explosive hazard facilities
used by a single customer.
    (3) Separate each public area containing any member of the public
in the open by a distance equal to -1133.9 + [389 * ln(NEW)] where the
NEW is greater than 450 pounds and less than 600,000 pounds.
    (e) A launch site operator may:
    (1) For a division 1.1 explosive only, employ no less than the
public traffic route distance of tables E-1 and E-2 of appendix E of
this part, to separate an explosive hazard facility from a public area
that consists only of a public traffic route.
    (2) Use the applicable equation provided by tables E-1, E-2, E-3,
and E-4 of appendix E of this part to determine the separation distance
for NEW quantities that fall between table entries.
    (3) Use a distance to calculate maximum permissible NEW using the
applicable equation of tables E-1, E-2, E-3, and E-4 of appendix E of
this part.
    5. Add Sec.  420.66 to read as follows:

Sec.  420.66  Separation distance requirements for storage of hydrogen
peroxide, hydrazine, and liquid hydrogen and any incompatible energetic
liquids stored within an intraline distance.

    (a) Separation of energetic liquids and determination of distances.
A launch site operator must separate each explosive hazard facility
from each other explosive hazard facility and each public area in
accordance with the minimum separation distance determined under this
section for each explosive hazard facility storing:
    (1) Hydrogen peroxide in concentrations of greater than 91 percent;
    (2) Hydrazine;
    (3) Liquid hydrogen; or
    (4) Any energetic liquid that is:
    (i) Incompatible with any of the energetic liquids of paragraphs
(a)(1) through (3) of this section; and
    (ii) Stored within an intraline distance of any of them.
    (5) A launch site operator must measure each distance as required
by Sec.  420.70.
    (b) Quantity. A launch site operator must determine the minimum
separation distance between each explosive hazard facility and all
other explosive hazard facilities and each public area and public
traffic route as follows:
    (1) For each explosive hazard facility, a launch site operator must
determine the total quantity of all energetic liquids in paragraphs
(a)(1) through (4) of this section. The quantity of energetic liquid in
a tank, drum, cylinder, or other container is the net weight in pounds
of the energetic liquid in the container. The determination of quantity
must include any energetic liquid in associated piping to any point
where positive means exist for:
    (i) Interrupting the flow through the pipe, or
    (ii) Interrupting a reaction in the pipe in the event of a mishap.
    (2) A launch site operator must convert the quantity of each
energetic liquid from gallons to pounds using the conversion factors
provided in table E-6 of appendix E of this part and the following
equation:

Pounds of energetic liquid = gallons x density of energetic liquid
(pounds per gallon).

    (3) Where two or more containers of compatible energetic liquids
are stored in the same explosive hazard facility, the total quantity of
energetic liquids is the total quantity of energetic liquids in all
containers, unless:
    (i) The containers are each separated from each other by the
distance required by paragraph (c) of this section; or
    (ii) The containers are subdivided by intervening barriers that
prevent mixing, such as diking. Where two or more containers of
incompatible energetic liquids are stored within an intraline distance
of each other, paragraph (d) of this section applies.
    (c) Determination of distances for compatible energetic liquids. A
launch site operator must determine separation distances for compatible
energetic liquids as follows:
    (1) To determine each intraline, public area, and public traffic
route distance, a launch site operator must use the following tables in
appendix E of this part:
    (i) Table E-7 for hydrogen peroxide in concentrations of greater
than 91 percent; and
    (ii) Table E-8 for hydrazine and liquid hydrogen.
    (2) For liquid hydrogen and hydrazine, a launch site operator must
use the ``intraline distance to compatible energetic liquids'' for the
energetic liquid that requires the greater distance under table E-8 of
appendix E of this part as the minimum separation distance between
compatible energetic liquids.
    (d) Determination of distances for incompatible energetic liquids.
If incompatible energetic liquids are stored within an intraline
distance of each other, a launch site operator must determine the
explosive equivalent in pounds of the combined liquids as provided by
paragraph (d)(2) of this section unless intervening barriers prevent
mixing.
    (1) If intervening barriers prevent mixing, a launch site operator
must separate the incompatible energetic liquids by no less than the
intraline distance that tables E-7 and E-8 of appendix E of this part
apply to compatible energetic liquids using the quantity or energetic
liquid requiring the greater separation distance.
    (2) A launch site operator must use the formulas provided in table
E-5 of appendix E of this part, to determine the explosive equivalent
in pounds of the combined incompatible energetic liquids. A launch site
operator must then use the explosive equivalent in pounds requiring the
greatest separation distance to determine the minimum separation
distance between each explosive hazard facility and all other explosive
hazard facilities and each public area and public traffic route as
required by tables E-1, E-2 and E-3.
    6. Revise Sec.  420.67 to read as follows:

Sec.  420.67  Separation distance requirements for handling
incompatible energetic liquids that are co-located.

    (a) Separation of energetic liquids and determination of distances.
Where incompatible energetic liquids are co-located in a launch or
reentry vehicle tank or other vessel, a launch site operator must
separate each explosive hazard facility from each other explosive
hazard facility and each public area in accordance with the minimum
separation distance determined under this section for each explosive
hazard facility.
    (b) Quantity. A launch site operator must determine the minimum
separation distance between each explosive hazard facility and all
other explosive hazard facilities and each public area and public
traffic route as follows:
    (1) For each explosive hazard facility, a launch site operator must
determine the total quantity of all energetic

liquids. The quantity of energetic liquid in a launch or reentry
vehicle tank is the net weight in pounds of the energetic liquid. The
determination of quantity must include any energetic liquid in
associated piping to any point where positive means exist for:
    (i) Interrupting the flow through the pipe, or
    (ii) Interrupting a reaction in the pipe in the event of a mishap.
    (2) A launch site operator must convert each energetic liquid's
quantity from gallons to pounds using the conversion factors provided
by table E-6 of appendix E of this part and the following equation:

Pounds of energetic liquid = gallons x density of energetic liquid
(pounds per gallon).

    (c) Determination of separation distances for incompatible
energetic liquids. A launch site operator must determine separation
distances for incompatible energetic liquids as follows:
    (1) A launch site operator must use the formulas provided in
appendix E of this part, table E-5, to determine the explosive
equivalent in pounds of the combined incompatible energetic liquids;
and
    (2) A launch site operator must use the explosive equivalent in
pounds to determine the minimum separation distance between each
explosive hazard facility and all other explosive hazard facilities and
each public area and public traffic route as required by tables E-1, E-
2 and E-3 of appendix E of this part.
    (d) Separation distance by weight and table. A launch site operator
must:
    (1) For an explosive equivalent weight from one pound through and
including 450 pounds, determine the distance to any public area and
public traffic route following table E-1 of appendix E of this part.
    (2) For explosive equivalent weight greater than 450 pounds,
determine the distance to any public area and public traffic route
following table E-2 of appendix E of this part.
    (3) A launch site operator must separate each explosive hazard
facility from all other explosive hazard facilities of a single
customer using the intraline distance provided by table E-3 of appendix
E of this part.
    (4) For explosive hazard facilities of a single customer, a launch
site operator must use the greater intraline distance to separate the
facilities from each other. For explosive hazard facilities used by
different customers a launch site operator must use the greater public
area distance to separate the facilities from each other.
    7. Revise Sec.  420.69 to read as follows:

Sec.  420.69  Separation distance requirements for co-location of
division 1.1 and 1.3 explosives with liquid propellants.

    (a) A launch site operator must separate each explosive hazard
facility from each other explosive hazard facility and each public area
in accordance with the minimum separation distance determined under
this section for each explosive hazard facility where division 1.1 and
1.3 explosives are co-located with liquid propellants. A launch site
operator must determine each minimum separation distance from an
explosive hazard facility where division 1.1 and 1.3 explosives and
liquid propellants are to be located together, to each other explosive
hazard facility and public area as follows:
    (b) For liquid propellants and division 1.1 explosives located
together, a launch site operator must:
    (1) Determine the explosive equivalent weight of the liquid
propellants as provided by Sec.  420.67(c);
    (2) Add the explosive equivalent weight of the liquid propellants
and the NEW of division 1.1 explosives to determine the combined net
explosive weight; and
    (3) Use the combined NEW to determine the distance to each public
area, public traffic route, and each other explosive hazard facility by
following tables E-1, E-2, and E-3 of appendix E of this part.
    (c) For liquid propellants and division 1.3 explosives located
together, a launch site operator must separate each explosive hazard
facility where liquid propellants and division 1.3 explosives are
located together from other explosive hazard facilities, public area,
and public traffic routes using either of the following two methods:
    (1) Method 1:
    (i) Determine the explosive equivalent weight of the liquid
propellants by following Sec.  420.67(c).
    (ii) Add to the explosive equivalent weight of the liquid
propellants, the net explosive weight of each division 1.3 explosive,
treating division 1.3 explosives as division 1.1 explosives.
    (iii) Use the combined net explosive weight to determine the
distance to public area, public traffic route, and distance to other
explosive hazard facilities by following tables E-1, E-2, and E-3 of
appendix E of this part.
    (2) Method 2:
    (i) Determine the explosive equivalent weight of each liquid
propellant by following Sec.  420.67(c).
    (ii) Add to the explosive equivalent weight of the liquid
propellants, the NEW equivalent weight of each division 1.3 explosive
to determine the combined net explosive weight.
    (iii) Use the combined NEW to determine the minimum separation
distance to each public area, public traffic route, and each other
explosive hazard facility by following tables E-1, E-2, and E-3 of
appendix E of this part.
    (d) For liquid propellants, division 1.1 and 1.3 explosives located
together, the launch site operator must:
    (1) Determine the explosive equivalent weight of the liquid
propellants by following Sec.  420.67(c).
    (2) Determine the total explosive quantity of each division 1.1 and
1.3 explosive by following Sec.  420.65(b).
    (3) Add to the explosive equivalent weight of the liquid
propellants to the total explosive quantity of division 1.1 and 1.3
explosives together to determine the combined net explosive weight.
    (4) Use the combined net explosive weight to determine the distance
to each public area, public traffic route, and each other explosive
hazard facility by following tables E-1, E-2, and E-3 of appendix E of
this part.
    (e) The launch site operator must analyze the maximum credible
event (MCE) or the worst case explosion expected to occur. If the MCE
shows there will be no simultaneous explosion reaction of the liquid
propellant tanks and the solid propellant motors, then the minimum
distance between the explosive hazard facility and all other explosive
hazard facilities and public areas must be based on the MCE.
    8. Add Sec.  420.70 to read as follows:

Sec.  420.70  Separation distance measurement requirements.

    (a) This section applies to all measurements of distances performed
under Sec. Sec.  420.63 through 420.69.
    (b) A launch site operator must measure each separation distance
along straight lines. For large intervening topographical features such
as hills, the launch site operator must measure over or around the
feature, whichever is the shorter.
    (c) A launch site operator must measure each minimum separation
distance from the closest hazard source, such as a container, building,
segment, or positive cut-off point in piping, in an explosive hazard
facility. When measuring, a launch site operator must:
    (1) For a public traffic route distance measure from the nearest
side of the public traffic route to the closest point of the hazard
source; and
    (2) For an intraline distance measure from the nearest point of one
hazard source to the nearest point of the next hazard source. The
minimum separation

distance must be the distance for the explosive quantity or NEW that
requires the greater distance.
    9. Revise Appendix E to part 420 to read as follows:

Appendix E to Part 420--Tables for Explosive Site Plan

            Table E-1--Division 1.1 Distances to a Public Area or Public Traffic Route NEW <= 450 lbs
----------------------------------------------------------------------------------------------------------------
                                                                                Distance to public
                          NEW (lbs.)                            Distance to public area   traffic route distance
                                                                        (ft) 1 2                 (ft) \2\
----------------------------------------------------------------------------------------------------------------
<=0.5.........................................................                      236                      142
0.7...........................................................                      263                      158
1.............................................................                      291                      175
2.............................................................                      346                      208
3.............................................................                      378                      227
5.............................................................                      419                      251
7.............................................................                      445                      267
10............................................................                      474                      284
15............................................................                      506                      304
20............................................................                      529                      317
30............................................................                      561                      337
31............................................................                      563                      338
50............................................................                      601                      361
70............................................................                      628                      377
100...........................................................                      658                      395
150...........................................................                      815                      489
200...........................................................                      927                      556
300...........................................................                    1,085                      651
450...........................................................                    1,243                      746
----------------------------------------------------------------------------------------------------------------
\1\ To calculate distance d to a public area from NEW:
NEW <= 0.5 lbs: d = 236
0.5 lbs < NEW < 100 lbs: d = 291.3 + [79.2 * ln(NEW)]
100 lbs <= NEW <= 450 lbs: d = -1133.9 + [389 * ln(NEW)]
NEW is in lbs; d is in ft; ln is natural logarithm.
To calculate maximum NEW given distance d (noting that d can never be less than 236 ft):
0 <= d < 236 ft: Not allowed (d cannot be less than 236 ft)
236 ft <= d < 658 ft: NEW = exp [(d/79.2) - 3.678]
658 ft <= d < 1250 ft: NEW = exp [(d/389) + 2.914]
NEW is in lbs; d is in ft; exp[x] is e\x\.
\2\ The public traffic route distance is 60 percent of the distance to a public area.

Table E-2--Division 1.1 Distance to Public Area and Public Traffic Route
                            for NEW > 450 lbs
------------------------------------------------------------------------
                                  Distance to public  Distance to public
            NEW (lbs)                area (ft) \1\    traffic route (ft)
------------------------------------------------------------------------
450 lbs < NEW <= 30,000 lbs.....  1,250.............  750.
30,000 lbs < NEW <= 100,000 lbs.  40 * NEW 1/3......  0.60 * (Distance
                                                       to Public Area).
100,000 lbs < NEW <= 250,000 lbs  2.42 * NEW \0.577\  0.60 * (Distance
                                                       to Public Area).
250,000 lbs < NEW...............  50 * NEW 1/3......  0.60 * (Distance
                                                       to Public Area).
------------------------------------------------------------------------
\1\ To calculate NEW from distance d to a public area:
1,243 ft < d <= 1,857 ft: NEW = d\3\/64,000.
1,857 ft < d <= 3,150 ft: NEW = 0.2162 * d \1.7331\.
3,150 ft < d: NEW = d\3\/125,000.
NEW is in lbs; d is in ft.

            Table E-3--Division 1.1 Intraline Distances 1 2 3
------------------------------------------------------------------------
                                                            Intraline
                       NEW (lbs)                          distance (ft)
------------------------------------------------------------------------
50.....................................................               66
70.....................................................               74
100....................................................               84
150....................................................               96
200....................................................              105
300....................................................              120
500....................................................              143
700....................................................              160
1,000..................................................              180
1,500..................................................              206
2,000..................................................              227
3,000..................................................              260
5,000..................................................              308
7,000..................................................              344
10,000.................................................              388
15,000.................................................              444
20,000.................................................              489

30,000.................................................              559
50,000.................................................              663
70,000.................................................              742
100,000................................................              835
150,000................................................              956
200,000................................................            1,053
300,000................................................            1,205
500,000 \3\............................................            1,429
700,000................................................            1,508
1,000,000..............................................            1,800
1,500,000..............................................            2,060
2,000,000..............................................            2,268
3,000,000..............................................            2,596
5,000,000..............................................            3,078
------------------------------------------------------------------------
\1\ To calculate intraline distance d from NEW:
d = 18*NEW1/3
NEW is in pounds; d is in feet
\2\ To calculate maximum NEW from given intraline distance d:
NEW = d\3\/5,832
NEW is in pounds; d is in feet
\3\ A NEW greater than 500,000 lbs is not allowed for division 1.1
  explosives. Therefore, the parts of the table that list NEW values of
  more than 500,000 lbs are only applicable to liquid propellants with
  TNT equivalents equal to those NEW values.

                                  Table E-4--Division 1.3 Separation Distances
----------------------------------------------------------------------------------------------------------------
                                                                Distance to public area
                           NEW (lbs)                            or public traffic route  Intraline distance (ft)
                                                                        (ft) \1\                   \2\
----------------------------------------------------------------------------------------------------------------
<=1000........................................................                       75                       50
1,500.........................................................                       82                       56
2,000.........................................................                       89                       61
3,000.........................................................                      101                       68
5,000.........................................................                      117                       80
7,000.........................................................                      130                       88
10,000........................................................                      145                       98
15,000........................................................                      164                      112
20,000........................................................                      180                      122
30,000........................................................                      204                      138
50,000........................................................                      240                      163
70,000........................................................                      268                      181
100,000.......................................................                      300                      204
150,000.......................................................                      346                      234
200,000.......................................................                      385                      260
300,000.......................................................                      454                      303
500,000.......................................................                      569                      372
700,000.......................................................                      668                      428
1,000,000.....................................................                      800                      500
1,500,000.....................................................                      936                      577
2,000,000.....................................................                    1,008                      630
----------------------------------------------------------------------------------------------------------------
\1\ To calculate distance d to a public area or traffic route from NEW:
NEW <=1,000 lbs
 d = 75 ft
1,000 lbs < NEW <= 96,000 lbs
 d = exp [2.47 + 0.2368 * (ln(NEW)) + 0.00384 * (ln(NEW))\2\]
96,000 lbs < NEW <=1,000,000 lbs,
 d = exp [7.2297 -0.5984 * (ln(NEW)) + 0.04046 * (ln(NEW))\2\]
NEW > 1,000,000 lbs
 d = 8 * NEW 1/3
NEW is in pounds; d is in feet; exp[x] is e\x\; ln is natural logarithm
To calculate NEW from distance d to a public area or traffic route (noting that d cannot be less than 75 ft):
0 <= d < 75 ft:
 Not allowed (d cannot be less than 75 ft)
75 ft <= d <= 296 ft
 NEW = exp [-30.833 + (307.465 + 260.417 * (ln(d)))1/2]
296 ft < d <= 800 ft
 NEW = exp [7.395 + (-124.002 + 24.716 * (ln(d)))1/2]
800 ft < d
 NEW = d\3\/512
NEW is in lbs; d is in ft; exp[x] is e\x\; ln is natural logarithm
\2\ To calculate intraline distance d from NEW:
NEW <= 1,000 lbs
 d = 50 ft

1,000 lbs < NEW <= 84,000 lbs
 d = exp [2.0325 + 0.2488 * (ln(NEW)) + 0.00313 * (ln(NEW))\2\]
84,000 lbs < NEW <= 1,000,000 lbs
 d = exp [4.338 -0.1695 * (ln(NEW)) + 0.0221 * (ln(NEW))\2\]
1,000,000 lbs < NEW
 d = 5*NEW1/3
NEW is in pounds; d is in feet; exp[x] is e\x\; ln is natural logarithm
To calculate NEW from an intraline distance d:
0 <= d < 50 ft:
 Not allowed (d cannot be less than 50 ft)
50 ft <= d <= 192 ft
 NEW = exp[-39.744 + (930.257 + 319.49 * (ln(d)))1/2]
192 ft < d <= 500 ft
 NEW = exp[3.834 + (-181.58 + 45.249 * (ln(d)))1/2]
500 ft < d
 NEW = d\3\/125
NEW is in pounds; d is in feet; exp[x] is e\x\; ln is natural logarithm

         Table E-5--Energetic Liquid Explosive Equivalents 1 2 3
------------------------------------------------------------------------
        Energetic liquids           TNT equivalence     TNT equivalence
                                  Static test stands  Launch pads
------------------------------------------------------------------------
LO2/LH2.........................  See Note 3........  See Note 3.
LO2/LH2 + LO2/RP-1..............  Sum of (see Note 3  Sum of (see Note 3
                                   for LO2/LH2) +      for LO2/LH2) +
                                   (10% for LO2/RP1).  (20% for LO2/
                                                       RP1).
LO2/RP-1........................  10%...............  20% up to 500,000
                                                       lbs
                                                      Plus 10% over
                                                       500,000 lbs.
IRFNA/UDMH......................  10%...............  10%.
N2O4/UDMH + N2H4................  5%................  10%.
------------------------------------------------------------------------
\1\ A launch site operator must use the percentage factors of table E-5
  to determine TNT equivalencies of incompatible energetic liquids that
  are within an intraline distance of each other.
\2\ A launch site operator may substitute the following energetic
  liquids to determine TNT equivalency under this table as follows:
Alcohols or other hydrocarbon for RP-1
H2O2 for LO2 (only when LO2 is in combination with RP-1 or equivalent
  hydrocarbon fuel)
MMH for N2H4, UDMH, or combinations of the two.
\3\ TNT equivalency for LO2/LH2 is the larger of:
(a) TNT equivalency of 8 * W 2/3, where W is the weight of LO2/LH2 in
  lbs; or
(b) 14 percent of the LO2/LH2 weight.

  Table E-6--Factors To Use When Converting Energetic Liquid Densities
------------------------------------------------------------------------
                                                          Temperature
               Item                  Density (lb/gal)       ([deg]F)
------------------------------------------------------------------------
Ethyl alcohol.....................                6.6                 68
Hydrazine.........................                8.4                 68
Hydrogen peroxide (90 percent)....               11.6                 68
Liquid hydrogen...................               0.59               -423
Liquid oxygen.....................                9.5               -297
Red fuming nitric acid (IRFNA)....               12.9                 77
RP-1..............................                6.8                 68
UDMH..............................                6.6                 68
UDMH/Hydrazine....................                7.5                 68
------------------------------------------------------------------------

Table E-7--Separation Distance Criteria for Storage of Hydrogen Peroxide
          in Concentrations of More than 91 Percent \1, 2, 3,\
------------------------------------------------------------------------
                                                  Intraline distance or
                                                 distance to public area
                 Quantity (lbs)                   or distance to public
                                                    traffic route (ft)
------------------------------------------------------------------------
10,000.........................................                      510
15,000.........................................                      592
20,000.........................................                      651
30,000.........................................                      746
50,000.........................................                      884
70,000.........................................                      989
100,000........................................                     1114
150,000........................................                     1275
200,000........................................                     1404
300,000........................................                     1607

500,000........................................                     1905
------------------------------------------------------------------------
\1\ Multiple tanks containing hydrogen peroxide in concentrations of
  greater than 91 percent may be located at distances less than those
  required by table E-7; however, if the tanks are not separated from
  each other by 10 percent of the distance specified for the largest
  tank, then the launch site operator must use the total contents of all
  tanks to calculate each intraline distance and the distance to each
  public area and each public traffic route.
\2\ A launch site operator may use the equations below to determine
  permissible distance or quantity between the entries of table E-7:
W > 10,000 lbs Distance = 24 * W1/3
Where Distance is in ft and W is in lbs.
To calculate weight of hydrogen peroxide from a distance d:
d > 75 ft W = d\3\/13824
Where distance d is in ft and W is in lbs.
\3\ For storage of Class 4 oxidizer inside of a building, the launch
  site operator must provide sprinkler protection in accordance with
  NFPA 430.

                         Table E-8--Separation Distance Criteria for Storage of Liquid Hydrogen and Bulk Quantities of Hydrazine
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                            Public area                                                     Public area
                                                           and intraline     Intraline                                     and intraline     Intraline
                                             Pounds of      distance to     distance to      Pounds of       Pounds of      distance to     distance to
       Pounds of energetic  liquid           energetic     incompatible     compatible       energetic       energetic     incompatible     compatible
                                              liquid         energetic       energetic        liquid          liquid         energetic       energetic
                                                              liquids         liquids                                         liquids         liquids
Over                                            Not Over     Distance in     Distance in            Over        Not Over     Distance in     Distance in
                                                                    feet            feet                                            feet            feet
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                60,000          70,000           1,200             130
100.....................................             200             600              35          70,000          80,000           1,200             130
200.....................................             300             600              40          80,000          90,000           1,200             135
300.....................................             400             600              45          90,000         100,000           1,200             135
400.....................................             500             600              50         100,000         125,000           1,800             140
500.....................................             600             600              50         125,000         150,000           1,800             145
600.....................................             700             600              55         150,000         175,000           1,800             150
700.....................................             800             600              55         175,000         200,000           1,800             155
800.....................................             900             600              60         200,000         250,000           1,800             160
900.....................................           1,000             600              60         250,000         300,000           1,800             165
1,000...................................           2,000             600              65         300,000         350,000           1,800             170
2,000...................................           3,000             600              70         350,000         400,000           1,800             175
3,000...................................           4,000             600              75         400,000         450,000           1,800             180
4,000...................................           5,000             600              80         450,000         500,000           1,800             180
5,000...................................           6,000             600              80         500,000         600,000           1,800             185
6,000...................................           7,000             600              85         600,000         700,000           1,800             190
7,000...................................           8,000             600              85         700,000         800,000           1,800             195
8,000...................................           9,000             600              90         800,000         900,000           1,800             200
9,000...................................          10,000             600              90         900,000       1,000,000           1,800             205
10,000..................................          15,000           1,200              95       1,000,000       2,000,000           1,800             235
15,000..................................          20,000           1,200             100       2,000,000       3,000,000           1,800             255
20,000..................................          25,000           1,200             105       3,000,000       4,000,000           1,800             265
25,000..................................          30,000           1,200             110       4,000,000       5,000,000           1,800             275
30,000..................................          35,000           1,200             110       5,000,000       6,000,000           1,800             285
35,000..................................          40,000           1,200             115       6,000,000       7,000,000           1,800             295
40,000..................................          45,000           1,200             120       7,000,000       8,000,000           1,800             300
45,000..................................          50,000           1,200             120       8,000,000       9,000,000           1,800             305
50,000..................................          60,000           1,200             125       9,000,000      10,000,000           1,800             310
--------------------------------------------------------------------------------------------------------------------------------------------------------

    Issued in Washington, DC, on February 7, 2011.
George Nield,
Associate Administrator for Commercial Space Transportation.

[FR Doc. 2011-3487 Filed 2-15-11; 8:45 am]
BILLING CODE 4910-13-P