Abstract
Wastewater treatment facilities play a vital role in preserving the environment by processing wastewater through multiple cleansing stages. At St. Mary's College Inc., Quezon City, there is a lack of research evaluating its wastewater treatment facility (WWTF), which limits the institution's ability to gain valuable insights into its operations. This quantitative descriptive-inferential study assesses the WWTF of SMCIQC using the quality of treated effluent data, composed of daily monitoring records and quarterly laboratory data. The research gathers its data through formal letters of request to the school's water treatment facility regarding the quality of water after treatment based on laboratory data, including ammonia as NH3-N, biochemical oxygen demand, fecal coliform, nitrate as NO3-N, oil and grease, phosphate as P (total and reactive), surfactant, and the school's monitoring data, which include pH levels and discharge volume. The document used for the laboratory data is the Certificates of Analysis, and the document used for pH and discharge volume is the Monitoring Logbook. The results of the interval estimate of pH through the school-based data from the year 2024 to 2025 had a margin of error of ±0.01610 with a 95% confidence level. This reflected the overall stability of the facility. The ANOVA results for the laboratory data from the school years 2022 to 2025, including ammonia, BOD, fecal coliform, nitrate, oil and grease, phosphate, and surfactant, had p-values greater than 0.05 and F-values lower than their respective F-critical values. This indicated no significant differences in mean concentration for the years mentioned. The overall parameters gathered, including pH, ammonia, BOD, fecal coliform, nitrate, oil and grease, phosphate, and surfactant, were largely found to be within the standards set by the LLDA, as referenced in the DENR DAO 2016-08 for effluent quality standards. The results showed minimal standard deviations, indicating consistency in the data. Collectively, these findings showed general compliance with the DENR general effluent standards. Although most of the parameters conformed to the given limits, there were occasional instances of exceedance, especially with ammonia. The findings, therefore, showed general operational stability with minimal deviation from complete regulatory compliance.
