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On Site Wastewater Treatment and Disposal – an Overview

On Site Wastewater Treatment and Disposal – an Overview

Our speaker for this Webinar is Peter Van Grinsven (past president of the EGP group) who will lead a discussion on general aspects of On Site systems as they apply to General Practice Engineers. Peter is Joined on a panel by Andrew Daker and Ian Watson. See Bio’s below. Pete van Grinsven ( CPEng and Fellow) has been designing wastewater treatment and disposal systems for almost 50 years. He has seen the growth of regulation and innovation in the discipline and watched successes and failures and the birth of systematic approaches to design and implementation of on-site wastewater control. He drove the process of getting approval for the proprietary Natural Flow Treatment System where grey and black water are treated separately. This meant finding innovative ways of verifying that the system worked. It gained acceptance from AC as an advanced primary system in 2008. Pete is also a structural engineer with considerable understanding of geotechnical issues around foundation and retaining structures. Andrew Dakers is a semi-retired professional engineer (BE, ME) based in Christchurch. After more than 20 years on the Natural Resources Engineering academic staff at Lincoln University, in 1999 Andrew set his own consulting company (ecoEng Ltd), retiring in 2022. Focusing primarily on engineering design of more than 1000 on-site wastewater systems, with the majority of his projects being in the South Island, but also village sanitation projects in a number of islands in the South Pacific. He was a member of the industry committee to develop on-site wastewater training unit standards for the Water Industry Training of the Agriculture ITO (2006). He has provided in-servicing training courses on on-site wastewater engineering in Australia, New Zealand the Cook Islands and Fiji. From 2009 to 2020, he has been an appointed member of the Management Audit Group for the On-site Effluent Treatment (OSET) National Testing Programme based in Rotorua. He is a member of Water NZ and a committee member of On-site Wastewater Management Systems SIG and is a past Board Member of the International Ecological Engineering Society (IEES). Ian Watson ME CPEng studied under Ian Gunn for his Masters in Public Health completing in 1981. Initially working with large water and wastewater treatment systems with Portals Water Treatment Ltd he subsequently worked on water projects in Papua New Guinea working for Beca. Ian established his own practice in 1982 providing mainly Structural engineering services , but he maintained Public Health involvement with On Site systems, and subdivision infrastructure.
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