Document ID: FAA-2011-0105-0001
Agency: faa
Document Type: Rule
Title: Explosive Siting Requirements
Posted Date: 2011-02-16T05:00Z

[Federal Register Volume 76, Number 32 (Wednesday, February 16, 2011)]
[Proposed Rules]
[Pages 8923-8939]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2011-3487]

[[Page 8923]]

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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 202-493-2251.

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 (202) 267-7427; facsimile 
(202) 267-3686, e-mail charles.huet@faa.gov. 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 (202) 267-3150; facsimile (202) 267-
7971, e-mail laura.montgomery@faa.gov.

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.

[[Page 8924]]

    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

[[Page 8925]]

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

[[Page 8926]]

(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, C9.5.6.1, 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,

[[Page 8927]]

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

[[Page 8928]]

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 C2.2.5.7.3 (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 C2.2.5.7.3 (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

[[Page 8929]]

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

[[Page 8930]]

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

[[Page 8931]]

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

[[Page 8932]]

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.

[[Page 8933]]

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 (202) 267-9680. 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

[[Page 8934]]

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

[[Page 8935]]

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

[[Page 8936]]

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

[[Page 8937]]

 
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

[[Page 8938]]

 
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

[[Page 8939]]

 
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