Just to tell you that I have been in contact with Birchcliff and here is the answer:

«Hi Paul,

 
We process roughly 30% of our gas through the AltaGas plant at Gordondale. 
Now have a look at the Plan;

Constructed by AltaGas, this 150 Mmcf/d sour natural gas processing plant, associated pipelines, was built in response to the significant increase in land sales and drilling activities in the Peace Region of northwestern Alberta. It is located in the Gordondale area of the Montney reserve area approximately 100 kilometers northwest of Grande Prairie, Alberta. Operations began in October 2012. The processing capacity of the plant was based on the immediate need of natural gas processing and hydrocarbon liquids recovery in the Gordondale area, as well as the production potential predicted in the area.

The facility processes gas gathered from Birchcliff’s Gordondale Montney development under a long-term take or pay contract.

The Gordondale Gas Plant (100 % ALA ownership)is the only facility in the area to offer high efficiency recovery of natural gas liquids (NGLs), also known as deep cut capability. The Plant also has peaking power plant generators which serve as emergency back-up generation for the plant as well as generate electricity and supply power to the grid when demand is high or supply is low.

Pretty long transportation to RIPET ;--» 1162 KMS

I d'ont know where the other 70% come from and which company is processing the gas.

Note : when you look at ALA ownership in many others processing facilities,it show you the ''huge'' assets they have and generate 47 % of Ebitda in the midstream sector . 
And they have de WGL utilities to generate 57 % of the ALA Ebitda on a constant and regulated environement .
Cannot be a better mix for an investor looking for stability and growth.