Fig. 2. Concentration of (a) NH3–N, (b) NO3–N, and (c) total P in leachate from oil-spiked control and treated sediments. For Inipol (Ip) samples treated with Ip only, the total organic nitrogen was determined as ammonia nitrogen using a Kjeldahl method, meaning there is no NO3–N data in (b). C, control; Ip, Inipol; Os, Osmocote; SN, soluble nutrients.