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Activated carbon (AC) prepared from residual fly (FA) was activated by combined CO₂-steam gasification and physically modified with procaine hydrochloride (PQ⁺Cl^-). Modified AC was used as low cost and effective solid phase extractor (SPE) for removal, total determination and chemical speciation of chromium(III&VI) in wastewater. Pseudo-second order rate equation is proposed for assigning the kinetics of chromium(VI) sorption in aqueous HCl (1.0 mol L^-1) by PQ⁺Cl^-- modified AC . The data were correlated with surface structure of the SPE. A dual separation mechanism of chromium(VI) as a binary complex ion associate [PQ⁺.CrO₃Cl^-] in/on the modified AC via "weak base anion exchanger" and an added component of “surface adsorption” is proposed. At 2 mL min^-1flow rate Sorption of spiked chromium(VI) at known concentrations (0.5-20 mg mL^-1) from water onto modified AC packed columns at 2 mL min^-1was achieved. The sorbed chromium(VI) species were successfully recovered (106.0±2- 110 ±3%, n=3) from AC packed column with NaOH (10 mL, 1.0 mol L^-1). Chromium(III) after oxidation to chromium(VI) was also enriched and eluted from the AC packed column and analyzed. Modified PQ⁺Cl^-AC packed column was also used for total determination and speciation of chromium(III & VI) species at trace levels in environmental water samples. Good apparent recovery percentage (94.6±6.3-102.0± 8.5 %) of chromium species was achieved confirming the analytical utility of the modified AC-packed column for removal, total determination and speciation of chromium(III & VI) species in environmental water samples.