(h) Mechanically expose the ends of the rockets by boring into the vault with diamond drills. A possibility exists that the fuze located in the warhead may be penetrated. This fuze contains lead azide and styphnate. These materials being friction and heat sensitive could detonate thereby activating the entire rocket explosive train and possibly detonating the entire vault.

(i) Utilize a diamond edge saw blade to cut through the concrete vault attempting not to touch the detonator or composition B explosive in the warhead or the igniter located between the propellant and the warhead. Since the exact location of the rockets is unknown, the possibility of hitting the igniter is deemed to be an unacceptable risk.

(j) Utilize a high pressure water jet (300 gpm at 4-5000 psi) to broach the concrete. It is anticipated that a five to twelve inch wide cut could be made. The hazard associated with the possibility of the jet's hitting the warhead detonator and cutting it open is considered excessive.

(k) Utilize shaped charges to penetrate the ends of the vault thereby exposing the rocket ends. The possibility of initiating the detonator, explosive charge or propellant is considered too great.

(1) House the vault in a suitable enclosure capable of containing the explosion and immerse the vault in a suitable solution which can chemically neutralize the GB agent. The feasibility of using a surplus ICBM launch facility as a "suitable enclosure" should be explored. Through a suitable mechanism, to provide an atmosphere of ammonia over the decontaminating solution. The vaults would then be explosively detonated with a sufficiently large charge to disintegrate them. It would be necessary to demonstrate the completeness of disintegration of the vault and its contents and decomposition of all agent to make this method acceptable.

(m) Several variants of the above-described methods were also proposed, but these are not discussed here because of their similarity in principle.

COMMITTEE MEMBERSHIP

1. Dr. Paul M. Gross-Chairman, Munitions Command Advisory Committee, and Emeritus Professor of Chemistry, Duke University.

2. Dr. Eugene H. Eyster-Division Leader, Los Alamos Scientific Laboratory. Formerly, Chief, Explosives Division, Naval Ordnance Laboratory.

3. Dr. Ralph E. Fadum-Dean, College of Engineering, N.C. State University. Also Special Consultant to Office, Chief of Engineers.

4. Dr. Ralph E. Gibson-Professor of Biomedical Engineering, Johns Hopkins University, and Emeritus Director, Applied Physics Laboratory.

5. Dr. M. King Hubbert-Professor of Geology and Geophysics, Stanford University. Also Former Member Advisory Committee for the Disposal of Atomic Wastes.

6. Dr. V. J. Linnenbom-Superintendent Ocean Science and Engineering Division, Naval Research Laboratory, Formerly Head, Radiochemistry Section. 7. Dr. H. M. Parker-Staff Consultant, Pacific Northwest Laboratories, Battelle Memorial Institute and Director, National Council on Radiation Protection.

FEASIBILITY STUDY-LAWRENCE RADIATION LABORATORY, NEVADA OPERATIONS OFFICE, U.S. ATOMIC ENERGY COMMISSION

PROJECT HARPIN

I. INTRODUCTION AND SUMMARY

A. Statement of the Problem

The Army is faced with public and Congressional opposition to the dumping of obsolete chemical munitions into the ocean. Munitions containing a total of about 135,000 pounds of GB liquid "nerve gas" are yet to be disposed of. An alternative proposal under consideration is to decompose the agent and destroy the munitions within the ionizing heat and radiation of an underground nuclear detonation. This alternative is identified as Project HARPIN.

Based upon the recommendations of an ad hoc committee to the National Academy of Sciences, the Army has established August 1, 1970, as the deadline for disposal.

The toxic gas is contained in the warheads of approximately 12,540 M-55 toxic rockets-each rocket also contains a 19-pound propellant charge and

about a two-pound burster charge. These munitions were sealed in concretefilled steel vaults (approximately 3% feet by 4 feet by 71⁄2 feet) in preparation for sea dumping.

This paper represents the combined judgments of LRL and NVOO regarding: 1. A preliminary hazards evaluation.

2. Engineering and construction feasibility.

3. Time and cost estimates.

4. Impact on the Weapons Test Program.

B. Summary and Conclusions

These obsolete chemical munitions can be reliably destroyed by an underground nuclear explosion. This operation can also be conducted with no undue or unusual onsite and offsite safety hazard if the structural integrity of the steel shipping vaults can be assured through the time of employment hole stemming. Event planning and execution, however, must acknowledge the possibility of gas leakage. Three different sites have been evaluated for this experiment:

Yucca Flat, NTS

Pahute Mesa, NTS

Other locations within CONUS

The primary difference between the sites is: (1) time; (2) cost; and (3) operational interferences.

C. Recommendations

If the HARPIN concept is accepted as the means of GB disposal, it is recommended that the following additional reviews be performed before the AEC accepts ultimate responsibility for this project. These reviews can be accomplished concurrent with emplacement hole drilling and mining if the overall project time frame must be compressed.

1. A structural analysis be performed on the concrete-filled vaults to investigate their load-bearing ability in a vertical stacking configuration and to investigate the integrity of the gas seal welds on the steel vaults.

2. The stability of the explosives in the burster and propellant charges be verified. If these explosives have deteriorated to the point where handling of the vaults is hazardous, we will recommend against the adoption of HARPIN and suggest that these munitions be disposed of in a manner which minimizes human handling (i.e., sea dumping).

3. Obtain additional information regarding the characteristics, effects and handling of the GB gas, and prepare a final safety evaluation. These reviews will be in addition to the "normal" evaluations of all nuclear detonations.

These additional reviews will be completed in sufficient time to permit a "sea dump" if HARPIN is judged to be unacceptable.

If the project is authorized, it is recommended that it be conducted on Pahute Mesa, NTS. This location will reduce to acceptable levels the mutual interference problems between this project and other NVOO activities, and yet can utilize the existing NTS capability base. It is estimated that about 15 months will be required from project authorization to NVOO through event execution. This schedule is not consistent with the desired August 1970 disposal date.

The following table summarizes the time and cost impacts of four different location options.

[Dollars in thousands]

If this project must be completed by August 1970, then an existing emplacement hole must be utilized. The only existing holes suitable for this event are in Yucca Flat. The accomplishment of this project in Yucca Flat will cause an unacceptable amount of interference with other ongoing NTS activities. A possible alternative for meeting the August 1970 date is to transport the vaults to the NTS before August 1970 and store them in a remote location (i.e., Pahute Mesa) until the HARPIN facility can be completed. A short move on the NTS might then be required before disposal.

II. TECHNICAL DESCRIPTION OF VAULTS AND ENCAPSULATED M-55 ROCKETS

The 418 vaults under discussion are constructed from 4-inch-thick steel plates. The steel was manufactured in accordance with Federal Specification QQ-S-741B. The plates are Grade A-ASTM, designation A7-61T. The dimensions of the vaults are 71⁄2 feet long, 4 feet wide, and 3 feet high. The vaults were assembled by double welding the seams. The weld seams of each vault with the exception of the lid are vacuum tested. This test data is not recorded and the test specification will be furnished at a later date. There are "I" beams (for lifting and stacking purposes) welded on the bottom of each vault. The "I" beams are 4 inches high and have a 4-inch-wide flange.

There are 30 M-55 area toxic rockets encapsulated in each vault. Each rocket is housed in its M-441 shipping and firing container. The rockets are imbedded in concrete in the vaults. The rockets were placed in the vaults in five layers of six rockets per layer. The first layer with the rockets equally spaced was laid on about two inches of concrete slurry placed on the bottom of the vault. Concrete slurry was then poured over the layer of six rockets until the layer was covered with concrete, then the second layer was emplaced. The remaining three layers were emplaced in the same manner. After the last slurry was poured, it was leveled to assure the lid could be fitted to the vault. There is no assurance that the rockets retained their positions in the vault as each layer was covered with slurry as successive layers were placed, or anytime prior to final set of the concrete. The lid was double seam welded on the vault after the concrete cured at least 28 days. There is no endwise orientation of the rockets recorded or known in the vaults. The 418 vaults are packed identically and weigh 6.4 tons each.

Background information relative to the characteristics of the rockets and GB was obtained from documents furnished to NVOO and LRL by the Department of Defense.

III. OPERATIONAL FACTORS

A. Need for a separate event

Project costs could be reduced (by cost sharing with the "host" event) if HARPIN is conducted as an "add-on" to another NTS event. We feel that this is an undesirable situation for the following reasons:

1. Only devices within a narrow yield range can be utilized for HARPIN. The yield must be in excess of 100 KT to assure destruction of the liquid GB (Appendix B contains LRL calculations regarding the required device yield). The upper yield limit is determined by the depth of the water table (1,800 feet in Yucca; 2,000 feet on Pahute). To facilitate mining activities, the HARPIN chamber should be above the water table. Based upon depth of burial, the maximum allowable yield for HARPIN would be 135 KT in Yucca and 185 KT on Pahute.

2. Most NTS events utilize developmental devices with a degree of uncertainty as to expected yield. HARPIN requires a guaranteed yield of at least 100 KT in order to assure, without question, that all of the chemical munitions are destroyed. 3. The NTS event schedule is very tenuous, with the actual event execution dependent upon the progress in the device development program. The actual execution of HARPIN as an add-on would be dependent upon progress in the event device development program.

4. Depending upon the purpose of the primary event, the inclusion of the HARPIN add-on may affect the primary experiment and degrade the value of the event.

5. The inclusion of a HARPIN add-on will cause serious interference problems with the preparations for the primary event. The presence of large amounts of high explosives and other hazardous materials within the Ground Zero complex will cause a severe disruption and delay in the normal event preparation activities. For the above stated reasons, we feel that HARPIN should be conducted as a separate event.

B. Construction and Support

1. Event configuration

LRL has ascertained that the chemical munitions can be reliably destroyed in the proposed event configuration by a device yield of 100 KT.

The planned event configuration is a 39-foot by 40-foot by 56-foot-high chamber located at about the 1,600-foot level of a 72-inch-diameter cased vertical shaft. The shaft diameter is determined by the size of the vaults. The chamber dimensions are determined by the total volume of all vaults and a trade-off between: (1) a spherical chamber for the efficient utilization of the nuclear device; and (2) a

reasonably simple to construct and stable chamber and vault configuration. The chamber depth is determined by: (1) the locations of acceptable mining media; and (2) a depth of sufficient size to contain the nuclear detonation. Appendix A to this paper includes a sketch of the proposed downhole configuration.

A second 36-inch cased shaft is proposed to serve primarily as an emergency escape route and as a backup ventilation shaft. A cross drift will connect the 36inch shaft to the main chamber.

In addition to normal utilities, the HARPIN facility may include: (1) downhole caustic showers for decontamination purposes; (2) an alcove in the cross drift for a "resident" medical team. A downhole monitoring system to detect gas leakage and a surface decontamination facility will also be required.

Some specialized equipment needed to handle the steel vaults must either be purchased or fabricated. Appendix A to this paper contains a more detailed construction plan.

Once the vaults are emplaced, the cross drift and the 36-inch access shaft will be stemmed. Following the removal of the surface mining equipment, the nuclear device will be emplaced in the normal manner, and the 72-inch shaft will be stemmed. No abnormal precautions appear to be necessary for event execution. Post shot drill back is not currently planned.

2. Evaluation of alternate sites

This project can be conducted at any one of three generalized locations: (a) Pahute Mesa, NTS

(b) Yucca Flat, NTS

(c) Other CONUS locations.

Each of the three locations are discussed below:

a. Yucca Flat, NTS.—Yucca Flat is a broad alluvial valley with known chamberable media at depths in excess of 1,600 feet. The water table is located at about 1,800 feet, so the potential mining depths are water free. There are two existing 72-inch cased holes in Yucca Flat which can be used for this project, if necessary. The existing NTS construction and support capability base can be used for this project.

A significant operational interference problem will result if HARPIN is conducted in Yucca Flat. The two existing holes are located less than 1⁄2 mile from the Rainier Mesa Road in Area 2, a heavily traveled, major access route on Yucca Flat paralleled by primary power transmission lines. The holes are also located 3⁄4 mile and 2 miles away, respectively, from the Area 2 contractor corporation yard. This yard is the work site and reporting location for 300 to 400 personnel daily.

The adjacent area (3 to 5 miles radius) is also the area where LRL conducts essentially all of its low to intermediate yield events on a continuing basis.

Depending on the final hazards evaluation of the HARPIN operations, a considerable area and immobile facilities could be denied the LRL test programs for a significant period of time. In addition, the Area 2 locations are subject to periodic ground shock which could be detrimental to the continued integrity of the downhole chamber.

b. Pahute Mesa (assume north end of Area 19).-Pahute Mesa is the location of medium to large underground nuclear tests. Dry chamberable geologic_formations can be found down to depths of about 2,000 feet. The existing NTS construction and support capability can be used if this project is conducted at Pahute Mesa. A suitable hole for this project does not currently exist at Pahute Mesa. Operations would be much more remote from existing facilities. The frequency of nuclear events is less in this area, although individual events are of higher yield. Separation from other sites is greater and the ground shock problem is usually decreased, although the more complex geology of Pahute Mesa makes shock prediction more difficult. The Pahute Mesa location would have a lesser impact on the weapons test program. The remote location will allow for onsite storage of large numbers of vaults prior to emplacement.

c. Other CONUS Locations.-A summary review of other possible HARPIN sites off the NTS but within the continental U.S. has been conducted. These sites were evaluated on the following criteria:

(1) Site suitable for a 100 KT underground detonation.

(2) Dry competent media for mining in the range of 1,500 feet to 2,000 feet deep.

(3) An adequate operational and logistics base for supporting this project. The only known area which meets the above criteria is on the NTS. The Central Nevada STS meets item (1), but has a severe groundwater problem and would

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require an increase in its base capability. Most of the areas which NVOO has evaluated for supplemental sites have high water tables. Little is known about the subsurface geology in those areas with apparently dry formations.

If HARPIN is to be conducted off the NTS, then a site selection program, including the drilling of exploratory holes, must be accomplished before work on the emplacement holes begin. A preliminary effects evaluation (including groundwater movement, seismic, offsite damage predictions, fallout, bienvironmental, etc.) must also be prepared before an offsite location can be confined. This effort will add at least six months and $500 K to the HARPIN project.

In addition to the hydrologic/geologic problems, none of the off-NTS sites have an adequate existing construction, logistical and M&O capability to support this project.

d. Summary of Sites.-Based solely upon operational interference considerations, and minimizing the potential hazards to onsite personnel, it is strongly recommended that HARPIN not be conducted in Yucca Flat.

Based upon operational, safety, time and cost considerations, it is recommended that HARPIN be considered for execution on Pahute Mesa rather than an off-NTS location.

C. Equipment

The availability of specialized and reliable equipment is necessary for the safe conduct of this project. Specialized equipment must be developed to remove the vaults from their shipping conveyance (presumably on a truck trailer in a horizontal position), raise to a vertical position for inspection, and transfer to the downhole hoists. Equipment must be developed to assist in the downhole handling of the vaults.

The downhole hoist and associated equipment must approach 100% reliability since any downhole accident with the vaults could have catastrophic results. Certain equipment associated with the safe handling of the toxic munition (i.e., gas monitoring systems, protective clothing, decontamination equipment, etc.) should be made available by the Army for possible AEC use.

D. Hazards and Safety Evaluation

1. Description of hazards

The hazards analysis investigated four general areas of concern: (1) the material involved; (2) the mechanics of the firing and fusing system; (3) surface operations necessary for emplacement; and (4) downhole operations necessary for final emplacement. Most of the hazards analysis of the materials was completed by the High Explosives Chemistry Section at LRL. It should also be pointed out that this analysis is less thorough than normally desired because of the lack of samples of the actual material, late arrival of reports concerning the propellant, as well as the fact that the chemists have not discussed problems associated with aging and decomposition with knowledgeable personnel at Hercules-Radford on the double base propellants. Items considered in some detail were the Composition B used in the burster charge, the propellant contained in the rocket, the chemical agent GB, as well as the squibs and fuse components and igniter contained in the warhead. The item of most concern is the 19-plus pounds of propellant contained in each rocket. Particular concern in this area is due to the lack of available samples of the propellant at the time of assembling these rockets, the lack of detailed information on the decomposition behavior, and the unknown effects on the decomposition as a result of the rockets being placed inside the vaults and then being subjected to the heat of hydration of concrete followed by exposure to the sun for approximately a year.

Assuming that further calculations and discussions with the Hercules-Radford personnel do not indicate decomposition characteristics of the double base propellant that would significantly increase its sensitivity, it would appear that the vaults can be handled safely consistent with the engineering plan. Even though the lids were welded on initially, we would recommend that no further heat sources such as welding be applied to the vaults and that they not be subjected to any avoidable drops. The review indicated that the Composition B, squibs, or igniter should not represent a significant hazard during emplacement operations. In evaluating the hazards associated with handling the chemical agent GB, it is felt that the vaults can be handled in a safe manner consistent with the engineering plan, assuming that the instruments used for detection are sensitive enough to provide adequate warning of a slow leaker in the hole. It would appear that the mechanisms of release for the GB are somewhat limited to either a slow leak from one or more of the vaults or a gross release as a result of an explosion of one