Battery Life Calculation, Sleeping and Wake modes
This isn't that hard that you need an on line calculator.

First determine the average current consumption:

In sleep mode, the current (1.6 uA) is so much smaller than the wake mode current that we can assume that this 1.6 uA is used 100% of the time.

In wake mode we have 40 mA for 3 seconds every 30 minutes = 30 * 60 = 1800 seconds. That is a duty cycle of: 3 / 1800 = 1/600 = 0.00167
So those 40 mA peaks average out to: 0.00167 * 40 mA = 66.7 uA

Total average current consumption: 1.6 uA + 66.7 uA = 68.3 uA

Now we look in the datasheet to see what battery capacity that gives us given a discharge to 3.0 V.

The nominal capacity of this battery is 8.5 Ah. Let's look in the graphs if that is the value we can use. Battery capacity decreases with increasing load current but the load current for that 8.5 Ah is 4 mA, a lot less than the 68.3 uA we need. So yes, we can use the 4 mA value, our 68.3 uA is so small that the battery's capacity is not deteriorated by it.

From graph 1 we can determine to which voltage the battery is discharged in the capacity test. All curves are quite flat above 3.0 V so when the voltage is below 3.0 V then the battery is quite empty already. So that 8.5 Ah is valid for discharging to 3.0 V.

So let's continue with that 8.5 Ah. 8.5 Ah means the product of current and hours is 8.5 Ah. So: 8.5 Ah / 68.3 uA (from above) = 124451 hours = 5185 days = 14 years !

In practice batteries for long life applications are often only guaranteed for a 10 years lifetime. The 14 years exceeds that. So when used in a product you should instruct the user to replace the battery every 10 years for optimal performance.