An auxiliary process and method for use in wastewater treatment plants, modifying conventional primary and secondary treatment, to condition the effluent for use as agricultural irrigation water containing liquified fertilizer and soil amendment materials. Primary sludge and skimmed materials are comminuted and added to the volume of organic materials available for secondary treatment. A bacterial inoculum is added to accelerate the microbial reduction of biodegradable materials into a biomass of cells. The separated predominantly cellular secondary sludge is processed to rupture the cellular structure thus releasing the protoplasm to colloidal suspension. Combined with the mainflow of secondary clarified effluent, the resultant micro-particulate effluent is thereby conditioned for effective chelation treatment to remove heavy metal ions and for effective disinfection with reduced requirements for toxic reactants. The product is discharged as agricultural irrigation water containing, in solution, agricultural fertilizers as nitrogen, minerals, carbonaceous compounds and oxygen, plus ligno-cellulose soilbuilding materials. The heavy metals may be separated and recycled as a by-product.