Entries for the 'Safety' Category
posted on December 05, 2012 17:19
This article was first published in the Summer 2012 issue of Spigot News, the Ohio EPA's drinking water program newsletter. Many thanks for allowing us to republish it!
Ohio EPA conducts sanitary surveys at least once every three years at community public water systems (PWS) and once every five years at non-community PWSs. The purpose of a sanitary survey is to evaluate and document the capability of a water system’s source, treatment, storage, distribution, operation and maintenance, and management. Each of these may favorably or adversely impact the ability of the system to reliably produce and distribute water that meets drinking water standards.
This article is the second installment in a series of articles to help small water systems identify the most common problems found during a sanitary survey or other investigatory site visit conducted by Ohio EPA staff. The first article focused on source water (well) deficiencies. This article will focus on some of the more common treatment equipment deficiencies which are found during inspections of small water systems. Future articles in this series will cover distribution deficiencies and other topics.
Backwash discharge lines: If you have a softener or a pressure filter, you backwash your equipment to clean and replenish the media. The waste that is produced when you backwash discharges into a floor drain or another pipe, which carries the waste to where it will be treated. If the pipe carrying the backwash wastewater from your treatment equipment is too close to, or even inserted into, the drain or pipe that carries the waste to treatment (see Figure 1), you could end up with back-siphonage.
This could occur if the pipe carrying the waste to treatment backs up and the wastewater is siphoned back into your drinking water treatment equipment, contaminating your treatment equipment with whatever waste the pipe is carrying. Solution: Ensure there is a sufficient air gap between the backwash waste pipe and the floor drain or the pipe conveying the waste to treatment to prevent backsiphonage (see Figure 2).
Softener tanks, cover, and salt: Softener brine tanks should be kept in sanitary condition. The brine solution should be kept free of dirt and insects. Solution: The best way to accomplish this is to completely cover the brine tanks with an appropriately fitting lid. The lid should not be over- or under-sized and should be kept in place on top of the tank. Also, the brine tank should not be overfilled such that the lid does not fit snug on the tank (see Figure 3).
All substances, including salt, added to the drinking water in a public water system must conform to standards of the “American National Standards Institute/National Sanitation Foundation” (ANSI/NSF). This is to ensure it is a quality product that will not introduce contaminants into the drinking water. Solution: Ensure the ANSI or NSF symbol can be located on the bags of salt you use or ensure your salt supplier can provide you with documentation from the salt manufacturer that it is ANSI or NSF certified.
Cartridge filters: Over time, cartridge filters will become clogged with iron or other minerals from your source water. When clogged, the filters become a breeding ground for bacteria. Solution: Ensure filters are replaced in accordance with the manufacturers’ specifications or even more often, depending on the quality of your source water.
General maintenance: Water treatment equipment should be accessible and cleaning solutions and other non-drinking water chemicals and materials should be kept away from the equipment. If treatment equipment is not accessible for Ohio EPA staff to inspect during a sanitary survey, it will not be accessible to the water treatment operator for routine maintenance or during an emergency. Likewise, non-drinking water chemicals stored in close proximity to treatment equipment can be an invitation for a mix-up or, even worse, intentional vandalism (see Figure 4). Solution: Keep clutter and non-drinking water chemicals and equipment away from drinking water treatment equipment. Preferably, these items should be stored in a different room.
posted on September 07, 2012 05:25
This article was first published in the Winter 2011 issue of Spigot News, the Ohio EPA's drinking water program newsletter. Many thanks for allowing us to republish it!
Ohio EPA conducts sanitary surveys once every three years at community public water systems (PWSs) and once every five years at noncommunity PWSs. The purpose of a sanitary survey is to evaluate and document the capability of a water system’s source, treatment, storage, distribution, operation and maintenance, and management; these all may adversely impact the ability of the system to reliably produce and distribute water that meets drinking water standards.
This article covers the sanitary survey or other investigatory site visits conducted at the water source and concentrates on the most common deficiencies found during the visit of small PWSs. Even though the article focuses on small systems, similar deficiencies can be found at larger public water systems. Future articles will cover treatment, distribution and other topics.
There are common deficiencies surveyors hope not to find when conducting a sanitary survey, or when following up on complaint investigations or responding to total coliform bacteria positive sample results. Figures 1 and 2 show poor water sources and figure 3 shows an acceptable water source. Figure 1 shows a well equipped with a sanitary seal which is missing bolts. It also shows that the casing is flush or in line with the finished grade, and the electrical wire and raw water line are exposed and unprotected. Although the well is vented, it does not have a screened vent. The well is also not protected from surface water runoff, other contaminants or critters.
Figure 2 shows a public water system well located in a parking lot. The well cap is missing bolts and therefore is not properly secured to the top of the well casing. There is also a depression surrounding the casing. If rainwater pools near the well, it can seep down along the casing and negatively impact the ground water and its quality. Located to the left of the well are bags of sodium chloride, which increases the potential for rust at the base of the well. Also, there is not enough protection around the well to prevent damage from motorized vehicles to the casing or electrical conduit.
Although you can’t see this in the picture, the well has a 1988 approved “National Sanitation Foundation” (NSF) well cap but it is not a “Water System Council” PAS-97 (or Pitless Adapter Standard, 1997) approved cap as required. The PAS-97 cap provides a properly screened vent which is not present in this cap.
Figure 3 shows an acceptable water source. The well casing extends approximately 24 inches above finished grade, which is beyond what is required (at least 12 inches above finished grade). The finished grade is sloped to drain surface water away from the well. The approved well cap fits flush over the top of the casing and electrical conduit; it provides a tight seal against the casing and prevents the entrance of water, dirt, animals, insects or other foreign matter. The well is also properly protected with concrete filled posts to protect it from motorized vehicles and mowers.
posted on July 09, 2012 07:17
I was at an asset management workshop recently that included a number of state regulators. The theme was asset management and certification, but O & M and the tie-in to understanding your assets kept coming up.
O & M Is Tied To Asset Management
I realize the title of this blog post is about SCADA systems, and many small communities don't even have them, but whether you use SCADA or not, the principles behind good O & M are important for all systems. It's all about understanding your system, the equipment, infrastructure, and treatment, as well as the process of running the plant (O & M). I know everyone hears about the importance of testing generators monthly and servicing pumps when recommended, but many times these things are low priority. Weeks turn into months and months turn into years. I was at a plant this summer that was using a federal grant to get a new generator for their water plant. I had just been in the wastewater plant for this same community this last fall where there was a perfectly good generator that would serve the purpose. I brought this up to the consultant managing the grant, but he said it wouldn't work. Unfortunately, the community had no warranty on the generator because they didn't follow the maintenance schedule. It had sat in a garage for number of years and not been ran. As a taxpayer, that's frustrating, but as a small systems advocate, it gives us all a black eye.
So On To Best Practices
At the workshop, someone from Michigan mentioned that one of their larger communities was planning to shut down their SCADA system for a week. This wasn't being done to allow upgrades or changes to the system, this was being done because the Water Supt. wanted to make sure his staff knew how to run the plant. This system is being proactive, both from an emergency standpoint, and also from an operations standpoint. We all rely on technology and automatic this or that for so many things these days, but to really "know" your plant, to be able to troubleshoot and tell when something isn't quite running right, you really have to have a comprehensive understanding of how your system works.
I Know, You Already Know Your Plant That Well
You are thinking, I already have that level of understanding of my plant, I know when something doesn't sound right, look right, or even feel right. Thats great, but what about the next level of support? What happens when you are not there? Do you ever take vacation or have to be out of town for a day or two? Is the person left in charge of your plant as familiar with your system as you are? Do they know your plant well enough to troubleshoot when a problem pops up? They need to have that level of understanding, or have something they can turn to that has those details.
That brings us back to one of those O & M things that are a pain, take time, and because you know the plant so well, keep putting off or don't see a need for. You should have an O & M manual for your plant. No one else can write it, and its only as useful as the information you put into it. It comes down to being prepared and taking full responsibility for the operation of the plant. That also means being prepared in case you can't be there for some reason.
First of all, develop an emergency response plan. There are templates available from a number of sources. You can contact a TA provider you work with, they will be able to get you started. If you want to look at some of the better ones, type in "emergency response plan" in our document keyword search, and use "type = templates". But, for those of you that already have an ERP, take the next step, develop an O & M plan for your plant. Pennsylvania, Massachusetts, and Florida require O & M plans, I'm sure there are others. New Jersey has an O & M template that operators can use to help them develop their O & M plan, as do Florida, Louisiana, and Vermont. Georgia has a guidance manual as well. It was also brought up at the workshop that Colorado is developing an O & M and training manual geeared toward walking you through developing an O & M plan for your facility. It sounds like it will be a great resource. Once the Colorado document is available, we'll post an update and provide those details. Lastly, if you need some help, email or call us. We can either help you directly or find someone in your area who can help you get started.
posted on May 25, 2012 06:22
With the sun higher in the sky and summer staring us down, it's a great time to remind your staff (and yourself) about best practices in health and safety for working outside. While these are practical tips year-round, summer can be a more dangeous time.
SmallWaterSupply.org Loves these strategies for working outdoors:
* Wear sunscreen, hats, sunglasses and UV-protective clothing for sun protection
* Wear bug repellant to protect yourself from mosquitos, ticks and chiggers
* Check your local air quality index if you have allergies or asthma
* Stay hydrated and comfortable with water in a BPA-free reusable water bottle
* Try to schedule breaks when the sun is highest in the sky
* Wear boots and long pants to reduce contact with poisonous plants or animals
For more details and downloadable factsheets, visit CDC's Hazards to Outdoor Workers website.
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