Reuse and recycling of waste water replenishes groundwater, a source of potable water for users, estimated at 40% of Marylanders, of drinking water wells. The most common method of waste water reuse is irrigation. However, the
microbiological and chemical content in waste water must be monitored and treated for reduction of pathogens to levels safe for humans. Guidelines to regulate pathogen levels in water reuse projects are published, among others, by:

• World Health Organization (WHO): “Guidelines  for the Safe Use of Wastewater and Excreta in Agriculture and Aquaculture –Measures for Public Health Protection (1989)
• US EPA: “Guidelines for Water Reuse”(1992, revised in 2004)
• Maryland Department of the Environment (MDE): “MDE Guidelines for Land Treatment of Municipal Wastewaters”( 1973, revised in 1987 and 2003)

The technical part of the presentation, its second half, focused on the guidelines published by MDE related to Class IV water discharged by waste water treatment plants. The first half of the presentation had focused on the role of civil engineers in civilized society, particularly as it relates to the tracking and elimination of waste water pollutants, and to the mind-set young engineers need, to make their mark in the profession as the presenter did in the groundwater discharge permitting field.

The presentation was delivered by C. T. Tien, Chief of the Groundwater Discharge Permit Division of the Maryland Department of the Environment. C. Tien has been with the Maryland Department of the Environment (MDE) since July of 1975. He was the principal author of the Maryland Sewerage Facilities Guidelines (1978) and helped to develop guidelines regarding groundwater discharge in Maryland including the MDE Land Treatment Guidelines (2003) and Draft Water Reuse Regulations (2009). C. Tien was named the Young Engineer of the Year (1979) by the Maryland Society of Professional Engineers. He is a Professional Engineer (PE) licensed in the State of Maryland. C. Tien has authored or co-authored 32 research papers, book chapters, conference proceedings and governmental publications. He was also an instructor at the University of Maryland, College Park for two graduate courses (2007-1014): (1) ENPM 637 Biological Principles of Environmental Engineering, and (2) ENPM 666 Groundwater Hydrology and Pollution Control. C. Tien’s specialties include, but are not limited to: (1) Water and wastewater treatment; (2) Water pollution control; (3) Waste management, and (4) Groundwater hydrology and water quality protection.

The event was arranged by Jeff Tan, the chairman of the ASCE-NCS Construction Committee for 2016. It started at 2pm on January 16, 2016 (Saturday) at the New Song Bible Fellowship Church, 6511 Princess Garden Pkwy Lanham, Maryland 20706. Attendees received one PDH credit.