Wednesday, May 13, 2015

Trip to GWRS

I brought the ENVH 569 students to the Ground Water Replenishment System GWRS in Orange County. Its an impressive facility and would have turned me into a full fledged Civil Engineer if I was any younger. It is refreshing to visit such an advanced approach to our drought in California. 
 
 The lab was also impressive. Those folks are progressive with their approach to testing all potential contaminants. The lab was designed with tours in mind and we could easily peer into windows with the lab techs hard at work.
 Everything is setup with tours in mind.

 We were all invited to taste the final product. Most students had the overwhelmingly surprising response: "It tastes like water".
 It is a clean facility that is designed for visitors to nose around on tours.

Our requisite blue helmet shot!

Monday, May 11, 2015

Simple sand filter construction


My water quality students in ENVH 568 built these sand  filters for a class requirement. They are now up and running in the LLU Environmental Microbiology Research Laboratory. We will use them for some class activities in the ENVH 569 sampling class. 


We started with a design and then a trip to the hardware store


We dry-fit the pieces together in the hardware store. This is where the students realized that there are many possible combinations.


Students discovered that there were a few possible combinations of diffuser pipes and spout exit styles. Our class built five filters with varying construction.

All filters had about 2 inches of 3/4" gravel around the pipes with another 2 inches of pea gravel on top of that (1/4" gravel). Those were separated by a cloth to minimize sand going into the gravel and then the bottom diffuser pipe.

Sand was added on top of that until it was about 2" below the spout. Our filters tested varying heights.


There were 5 filters built and are now hooked up to a recirculating water system. They will be tested for arsenic and E.coli removal in our ENVH 569 class.