The inner Oslofjord has undergone many changes in ecological quality throughout time. The Vestfjorden Avløpsselskap (VEAS) wastewater treatment plant has been involved in these changes with a generally positive effect. Given current analytical tools (CTD, total organic carbon (TOC), trace metals (TM), foraminifera, current meters), assessment of the impact (ecologically) that VEAS is having on the benthic zone surrounding the discharge pipes was conducted in fall 2017. This study found an incongruity in ecological quality between benthic areas north and south of the discharge area. Based on sample collected in 2018, the work of this thesis looked to confirm this discrepancy, add temporal markers to tie data collected at this site with data from the rest of the inner Oslofjord, assess the efficacy of foraminifera as indicators of ecological status, and search for a possible mechanism for discrepancy by studying current and circulation regimes in the area near the VEAS discharge. While unable to confirm the data values found in TM analysis in 2017 or the impact of currents in the area on the discharge regime, radiometric dating of a new core placed the changes seen in the area around VEAS in temporal context with what has happened to the inner Oslofjord as a whole. Additionally, discrepancies between values from different cores taken from the “same” location have led to better understanding of random and systemic methodological errors in analysis of samples specifically TOC and trace metals. Finally, foraminifera analysis along with dating of the core supports other research on the effectiveness of these organisms as indicators of ecological quality.