Downhole core plug apparatuses and related methods

A method of sampling a production well comprising:

• deploying one or more core plug holding apparatuses into one or more side pocket mandrels of a completion, wherein
• each core plug holding apparatuses comprising:
• a tubular member configured to be inserted into a side pocket of a mandrel, the tubular member having an uphole end, a downhole end, and a core plug section located between the uphole end and the downhole end, wherein the core plug section is used for housing of one or more core plug samples and wherein tubular member includes one or more open orifices formed in the core plug section, wherein the core plug samples are used for one or more of microbiological sampling, geochemical sampling, corrosion sampling, and geological sampling;
• holding the one or more core plug holding apparatuses in the one or more side pocket mandrels for an incubation period;
• and
• retrieving the one or more core plug holding apparatuses from the one or more side pocket mandrels after the passage of the incubation period.

A gas lift system for use in a production well, the gas lift system comprising:

• a production tubing extending into the production well and including one or more side pocket mandrels at one or more depths;
• and
• one or more core plug holding apparatuses, each of the one or more core plug holding apparatuses comprising:
• a tubular member configured to be inserted into a side pocket of a mandrel, the tubular member having an uphole end, a downhole end, and a core plug section located between the uphole end and the downhole end, wherein the core plug section is used for housing of one or more core plug samples and wherein tubular member includes one or more open orifices formed in the core plug section, wherein the core plug samples are used for one or more of microbiological sampling, geochemical sampling, corrosion sampling, and geological sampling, and
• wherein each of the one or more core plug holding apparatuses being installed in one or more of the side pocket mandrels.