Source code ecological footprint
CJam, 33 31

"",AA#b:c~


There are 11300000000950000000034000000011600000001010000000115000000011600000000340000000061000000003300000000420000000058000000010500000000500000000102000000009800000000490000000102000000009800000000490000000098 null bytes between the double quotes.

The code is equivalent to

11300000000950000000034000000011600000001010000000115000000011600000000340000000061000000003300000000420000000058000000010500000000500000000102000000009800000000490000000102000000009800000000490000000098
AA#b:c~


which can be tested online.

How this works

"",  e# Push the length of the string.
AA#  e# Push 10000000000.
b    e# Turn the length into the array of its base-10000000000 digits.
:c   e# Cast each digit to character. This pushes the following:
     e# q_"test"=!*:i2fb1fb1b
~    e# Evaluate the string.


How that works

q_     e# Read all input and push a copy.
"test" e# Push the string "test".
=!*    e# Check for inequality and repeat the string 0 or 1 times.
       e# This replaces input "test" with the empty string.
:i     e# Cast each character to integer
2fb    e# Replace each integer by the array of its base-2 digits.
1fb    e# Replace each array of base-2 digits by the sum of its digits.
1b     e# Add the sums of digits.


This source code has an ecological footprint of 75.