Ask The Operator: Water Monitoring 4513

John C. Anders

Lee Chate is the operator of the new Anytown Sanitary Landfill, Anytown, U.S. Employed by a county government, he does not have extensive staff, and although he is the "boss" at the landfill, he often mounts a piece of heavy equipment to help out.

Lee operated the local "dump" for years, but he is discovering that his new landfill is not just a dump anymore. Lee's facility strives to protect its employees and the surrounding environment, so equipment must function properly, traffic through the facility must flow logically and smoothly, and site activities must be closely monitored to ensure a safe and secure operation. Follow Lee over the next few months as he faces issues such as groundwater, surface water and landfill gas monitoring; waste stream inspection; health and safety; and construction and closure.

Lee basically understands what is required by regulations, but he often calls his consulting engineer and other landfill operators for advice. And he learns from his own experiences as well as those of others.

In this first article, Lee tackles issues related to groundwater and surface water monitoring. Lee's local governing body is considering hiring a new laboratory, and he is concerned about the transition. He knows that Mike Walk of the HAM Sanitary Landfill in Peterstown, W.V., has dealt with this type of issue in the past, so he calls him for advice.

Lee: Mike? Lee Chate here at Anytown.

Mike: Yes, Lee, how are you? How was your vacation?

Lee: Fine, the bass were hitting great. Wish I could have stayed longer. Mike, the reason I called is the county is thinking about hiring another laboratory to do the groundwater sampling, and I'm concerned about bringing someone new into this site. You've dealt with this kind of thing before, haven't you?

Mike: I sure have. One thing you need to do is follow the new people around and watch them when they come to do their first sampling event. You have a basic understanding of your well system and what's needed to perform the monitoring. So watch them until you feel comfortable that they're doing a good job.

Lee: That's a good idea, Mike. It's not that I don't trust them, I just have never worked with them before.

Mike: Right. Another thing - request copies of all of their field notes. This is good documentation to have when you review their invoices. The information is also handy to know what level of effort is necessary to monitor your site. It's beneficial for you to keep a good working knowledge of your system.

Lee: Good, I'll do that. Any other thoughts?

Mike: Make sure access is clear to all the well sites. You don't want the sampling crew held up because you're having to clear roads. Also, I've had to abandon a well because it did not have enough of a water column after it was purged. Keep an eye on those field notes. If a well doesn't have enough water in it to fill all of the sample jars, you may have to replace it.

Lee: Thanks, Mike. I'll remember that.

Mike has given Lee some helpful tips in dealing with groundwater sampling. As Lee said, it is not that he does not trust the laboratory, he just has never worked with it before. Lee needs to feel comfortable with the company doing the sampling and analysis. He has a good understanding of what is needed to monitor the groundwater, but he does not have the time or the staff to be able to do it himself.

Checking Sampling Lee knows that Dinwiddie County, Va., is resampling its wells to confirm the results of its most recent sampling. Lee calls Denny King, solid waste director, to find out how that is progressing.

Lee: Denny, Lee Chate here at Anytown.

Denny: Lee, how are you?

Lee: Fine, Denny. Listen, I heard you are resampling the wells there. What is going on?

Denny: Well, the last sampling event showed some statistically significant increases in some of the parameters. We are resampling to confirm the results.

Lee: I see. Think you'll be okay?

Denny: I'm not sure, Lee. We found some inconsistencies in the way the field procedures were handled. We're hoping that was the problem.

Lee: How are you evaluating that?

Denny: We're doing a couple of things. We are using an environmental consultant to do the sampling. They are getting duplicate samples and using two labs to do the testing. We're trying to make sure that all sampling procedures are followed right. Don't get me wrong, there are good labs out there that can do the job, but hiring an environmental consultant to do the sampling and testing makes us feel that everything is being done right.

Lee: There are a number of labs out there, but I guess if they haven't done much sampling on landfills they may not be up on what's needed.

Denny: That's right. Whoever does your sampling and testing, make sure they know what they are doing. Make sure the specs they bid against are very tight. Don't leave room for interpretation.

Lee: We have a groundwater monitoring plan as part of our operations manual. That should be what the labs bid against, right?

Denny: Right. Have the consultant who developed your plan help you with the bidding and evaluation of the bids. He can help you oversee the actual sampling, testing and data evaluation. He may even be able to do the whole job himself.

Lee, this is a critical issue. Make sure you are doing the best you can do on this groundwater monitoring. If the data is not right, you're setting yourself up for trouble.

Lee: Thanks, Denny. I'll keep that in mind. Hope everything works out okay for you.

Denny's advice seems to complement Mike's advice: Be sure whoever performs the regular sampling and analysis of the groundwater at your landfill is experienced. As Denny said, there are labs that do a good job of monitoring, but if they are not experienced at monitoring landfills, you could be asking for trouble. The same goes for consultants. No matter who you hire, make sure the services are what you need to stay compliant with regulations. The performance of your facility will be based in part on what the groundwater monitoring results are telling you, so make sure the data is correct and defensible.

Surface Water Lee's attention now turns to surface water monitoring. His facility is part of a stormwater group that has just received a National Pollutant Discharge Elimination System (NP-DES) permit for the discharge of stormwater from industrial activity. Landfills are categorically included as an activity requiring a permit.

Lee has to monitor two rainfalls each year and report to the Environmental Protection Agency (EPA). His options are to sample manually or with an automatic sampler.

Bill Wilson of the Solid Waste Department at Henrico County, Va., has performed his sampling manually and with automatic samplers. Lee calls him to get his thoughts.

Lee: Bill, Lee Chate at Anytown.

Bill: Yes, Lee. What can I do for you?

Lee: Bill, I've just got my Stormwater NPDES Permit, and I need to decide on how to do the monitoring. You've done this kind of sampling haven't you?

Bill: Sure have, Lee. I've used automatic samplers and have done the sampling manually.

Lee: I'm sure both ways have their pros and cons.

Bill: You're right. We have had success and failures using both methods. One of the biggest problems we had with the automatic samplers was vandalism. We had several units shot at and destroyed. We tried to make security enclosures for them, but it didn't seem to help. The marine batteries we were using as power sources were a hot target. We had about eight of those stolen. As a result of the vandalism, we missed several rainfall events that would have been sampled.

Lee: If the area had been safer, do you think you would have had better success?

Bill: In some cases. Another factor was the general characteristics of the sampling location. We were monitoring some continuously flowing streams. The wooden weirs we built didn't hold up under what were some record rainfalls. A couple of them washed out or were overtopped. In one case, beavers had chewed through the bottom of the notch in the weir. That threw the flow readings off completely. The beavers also built dams upstream which obstructed flow.

Lee: I believe my sampling locations will be in the pipes discharging from the stormwater ponds. That should make a difference.

Bill: Yes, it should. The location should be safer for equipment, and for people. That was also a concern when we monitored manually. Some of the areas were very remote. If we had to sample late at night or very early in the morning, we were armed. But if your sampling points are within your facility, you probably won't have those kinds of problems. Either method will work for you. It depends on what you can afford, and the staff and time you can dedicate to it.

Lee: What do you mean?

Bill: Well, automatic samplers are expensive. But they can do the job. When you are trying to sample rainfall events, there's no way to predict the amount of rainfall with enough accuracy to sample based on flow. You will need to sample based on time, and take those samples and prepare the flow-weighted sample for the laboratory. That's the only way you can sample any storm that comes along. And you can catch storms that occur during late night, early morning, weekends, holidays, that kind of thing.

Lee: Sounds like I should just forget about manual sampling.

Bill: Not necessarily. Manual sampling may fit your budget better. You will also have a quicker response time in getting the samples to the lab. For your testing parameters, you will have to get the samples to the lab within 24 to 48 hours from the time of sampling. With manual sampling, though, you are more likely to miss storms that occur during off-hours, weekends or holidays unless you have dedicated personnel. It's kind of difficult to gauge when to respond. You have to keep a closer eye on the weather and stay ready if it looks like it is going to rain. We set up to manually sample at times, and it didn't rain at least 0.1 inches, the minimum rainfall amount the regs require.

The rainfall and response time are problems for the automatic samplers, too. If the 0.1 inches of rain is not at least 72 hours from the last 0.1 inches of rain, the sampler will have to be delayed. The delay must be set manually. Even if you use automatic samplers, someone must check it to know if it has sampled.

You'll need to keep in close contact with the lab as well. If there is a chance a sampling event will occur on weekends, etc., you need to alert the lab as soon as possible. Most labs will work with you as long as you give them enough notice.

Lee: This sounds a little more complicated than I had thought.

Bill: Well, it can be. But if you do some good up-front planning, you should do okay. Let me know if I can help.

Lee: Thanks, Bill.

Bill has given Lee the kind of advice that comes only from experience. Regulations dictate what is required, but do not always offer help on how to comply. In the case of stormwater sampling, two very helpful manuals are NPDES Storm Water Guidance Document, EPA 833-B-92-001 (July 1992) and Guidance Manual For The Preparation Of NPDES Permit Applications For Storm Water Discharges Associated With Industrial Activity, EPA-505/8-91-002 (April 1991). Some publishing companies which specialize in technical publications carry a guidance manual.

However, there is no "off-the-shelf" answer or approach. Decide what you need and what you can afford. Then decide if you are going the manual sampling route or the automatic route. Most automatic sampler manufacturers will offer a rental agreement. This may be more economical for tight budgets.

Lee certainly has his hands full. But with proper planning and research, he should keep his head above water.