Escape Pods

If a major hull breach occurs, and it becomes impossible to contain the damaged region, then the colony must be evacuated. Elevators located in the spokes of the colony will be used as escape pods, which will evacuate the entire colony within 15 minutes. See Internal Transportation for more information on the regular function of spoke elevators. 
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Food Storage

Each escape pod is designed to sustain 45 people in space for a month, until rescue mission can arrive. Food storage must be allocated to meet those needs. According to NASA, an astronaut consumes about 1.8 kg of dried food each day. Thus, 45 people will require 2.5 tons of food to live for a month in the escape pods. With rationing, that number could potentially be extended to 40 days. Assuming an average density of 0.8 tons per cubic meter, this will require 3.1 cubic meters of storage space in each pod.
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Credit: NASA

Water

NASA states that water consumption is around 2.4 kg per person per day on the ISS, of which 1.6 kg is for drinking water, and 0.8 kg is for rehydrating dried food. Another article says that astronauts on board the ISS require 4 kg of water to bathe (compared to 40 kg on Earth!). If we assume a tight bathing schedule of every four days, the total water requirement for one person per day will become 3.4 kg. 45 people for a month brings the total to 4.6 tons, or 4.6 cubic meters. Additional water will be stored for use in fuel cells, which could also be extracted, detailed below. 
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Energy

Solar Power

The escape pods will be powered by solar arrays. On the ISS, 6 astronauts require 80 kW power (see source here), so 45 people will need 600 kW. A NASA report states that solar array specific power is as high as 150 W/kg at 1 AU, which means to power an escape pod we will need solar panels weighing 4 tons. For a margin of safety, assume 6 tons.

NASA has developed solar cells with over 40% efficiency, which will produce over 540 W/m^2 at 1 AU. Correspondingly, the required area of solar panels would be 1100 m^2 at 1 AU. 

Note that the specific power or power density of solar arrays depend on distance from the sun, and the data above was specific to 1 AU, which is the distance from Earth to the sun. 

Credit: NASA

Power density is proportional to the inverse square of distance - for example, at 2 AU the power density would be 1/4 of that at 1 AU, and at 0.5 AU the power density would be 4 times of that at 1 AU. ​

Fuel Cells

Additionally, fuel cells will be used to store energy when there is no direct sunlight. Fuel cells convert hydrogen and oxygen into water, in the process releasing energy and heat. The heat and water produced will be used for temperature control, and water supplies (if necessary). When not used, water will be electrolyzed into hydrogen and oxygen to recharge the cell. See this NASA article for more about the air and water cycle in the ISS.

NASA's target is to produce fuel cells that have an energy density of ~300 W/kg, which we will assume to be possible (see source here), so the mass of fuel cells will be 2.0 tons for each escape pod. If only considering existing technologies, the mass would be 5.9 tons based on these numbers.

H2/O2 fuel cells have an efficiency of ~60% (see source here), and their combustion produces 286 kJ of energy per mole of H2. Thus, about 170 kJ/mole of energy is usable. Powering the pod for up to 24 hours without sunlight will require 3.05*10^5 moles of hydrogen, which will produce the same moles of water, equivalent to 5.5 tons of water (5.5 cubic meters). 

The benefit to this design is that water could be allocated between fuel cells and drinking water. If there is no need to store energy because the escape pod is constantly receiving adequate solar power, water supplies for on board personnel could be extended to up to 65 days; vice versa, if sunlight is blocked for over 24 hours, drinking water could be temporarily allocated to the fuel cells and converted back at a later time, extending the operation limit to 44 hours. 

A simplified overview of a H2/O2 fuel cell. Credit: Institute of Physics

Space Suits