Cleaning out the septic holding tank w/Campa-Chem Naturals

http://www.thetford.com/HOME/PRODUCTS/ChemicalsCleaners/CampaChemNaturalProducts/tabid/126/Default.aspx

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Park might have a sewer set up that is unusual or uncommon. Example: our park has what is called "recreational septic tank" system through out the park which is actually a very small system. Your Mom has probably talked to her neighbors and knows what works for her situation.