Small Unit Assaults

I ran into an interesting document on PublicIntelligence.net that is allegedly prepared by the TRIPwire people at DHS. I have to say ‘allegedly’ since I have no way to verify that it is a real document; but I believe it to be legitimate. It describes small unit tactics that have been applied in various attacks in S. Central Asia. It also provides some suggestions for making it difficult to conduct such attacks against public facilities in the US.

Nothing in this document provides information about intelligence on a planned attack like this in the US, nor even claims that one is reasonably likely. The closest they come is the statement (pg 3) that “the same TTPs [Tactics, Techniques and Procedures] proven successful overseas such as in Mumbai or in Afghanistan could be adopted for use in the United States”. They certainly don’t make any claim or even discuss the use of such tactics against chemical facilities. So, I’ll make that case; that such tactics could very successfully be employed against chemical facilities.

Easy Targets

Chemical production facilities are typically fairly large installations with long fence lines and a low population density. The real targets within most installations would be the large chemical storage tanks. Most of these tanks are not hardened (pressure tanks being the main exception) so relatively small explosive charges placed at the base of the tanks can cause catastrophic release of the chemicals within.

The resulting pools of flammable and/or combustible chemicals can be easily ignited causing large fires on site that could damage additional storage tanks. In fact, such fires in tank farms containing pressurized tanks of flammable gasses or toxic gasses would be the easiest attack methods to successfully execute against such tanks.

Multiple two or three man teams would the ideal way to place large numbers of explosive devices on tanks in multiple tank farms. With the devices set to go off even nearly simultaneously, even if the teams are neutralized fairly quickly, the limited bomb response teams in most communities would not have enough time to search for and neutralize even a significant number of the devices before they start going off.

Facility Penetration

Without a really large and mobile guard force, it would be practically impossible to respond to multiple penetrations of the fence line in a timely manner. Aggravate the response teams by setting off a small vehicle borne improvised explosive device (similar in size and complexity to the ones currently being used in some Mexican border towns) on the other side of the facility and the entrance teams are unlikely to be intercepted until they announce their presence by shooting at personnel in the more densely populated process sections of the facility.

Employing such devices at entrance gates would be even more effective drawing any on-site guards to protect access through the gate. It would also and slow any off-site response forces from moving through the gates as they would have to maneuver around the wreckage.

To draw the response forces from searching for the planted explosive devices, the assault teams would move to the production areas shooting at anyone that they encountered. If they could reach production control rooms, office structures or security control rooms, any response forces would remain focused on the teams until the first explosions started in the tank farms.

The larger the facility, the more effective this type of attack would be. This would be especially true for large petrochemical refineries. While larger facilities would have better security, it is impossible to defend the long fence lines. Additionally, the owner/operators of these types of facilities would be the least likely to have armed on-site guard forces. The potential problems with weapons discharges in such facilities are routinely used to justify not using armed guards or on-site response forces.

Counter Measures

Large chemical processing facilities are going to have to take a number of well defined actions to reduce the likelihood of these attacks being conducted against them. First and foremost they are going to have to use aggressive perimeter patrolling techniques to prevent the reconnaissance activities that must precede such attacks.

Second they are going to have to employ their defenses in depth to hamper the movement of attackers within the facility. Multiple internal fence lines and separate fencing of tank farms will be required. All fence lines must be backed up by intrusion detection and video surveillance to allow identification of the location of intruders at all stages of the attack.

Third such facilities are going to have to review this tankage disposition. Flammable and combustible liquid storage tanks should not be contained within the same diked area as pressurized tanks containing flammable gasses and non-flammable toxic gasses. This will help to limit the ability of attackers to successfully breach these tanks without taking a great deal of time properly emplacing advanced explosive devices on these tanks.

Finally, large petrochemical facilities are going to have to take a serious look at the issue of arming internal security guards and security response forces. Very professional forces will be required to do this, forces with extensive training on fire discipline and very familiar with potential inherently dangerous areas of the facility where firearms may absolutely not be used. Security companies are going to have to look to alternative weapon systems that do not employ burning propellants.

Security managers at large chemical production facilities, especially petrochemical facilities are going to have to take a serious look at this type of attack. Preventing these attacks are going to require aggressively looking for reconnaissance and planning activities as well as close cooperation with Federal, State and local law enforcement agencies. Preventing these attacks will be much more effective than stopping them once they have started.