Surveying the DEW Line Clean Up

by Bob Holtkamp

I’m working in the high Arctic on a project called the DEW Line Clean Up (DLCU). DEW is an acronym for distant early warning systems, and the DEW line is a joint project of the Canadian and American military.

When the Cold War began in the early 1950s we decided we needed a protective warning system in case the Russians were to attack us from the north, so we constructed a line of radar facilities in the high Canadian arctic to keep vigil, which we still do today.

The DEW includes 21 major sites and another 21 corresponding intermediate sites. The main facilities are all quite elaborate and are overseen by an engineer with Defense Construction Canada. The DEW is now being called the NWS, or NorthWarning System, and is still a joint operation with The United States. (For more on the DEW, see the Northern Lights column in the July 2008 issue.)

The Problem

Unfortunately, for years mountains of garbage, toxins, PCBs, etc. were deposited on hundreds of acres of pristine Arctic tundra because of the DEW line construction and use. There was no way to dispose of it properly, and nobody cared. Today, we do care and are doing something about it. Some of the sites are being decommissioned and demolished, and others are being cleaned for ongoing service.

The hydrocarbons typically come from fuel spills. Over the years, fuel was barged into big holding tanks down at the beach and piped a few kilometers over the surface up to the facilities. These sites were identified by onsite investigators using historical documents and testing to verify any spill areas. Some of the sites are being entirely dismantled, taken right down to the ground. When we’re all done, you won’t know a site was there.  Other sites will remain in operation, so we are cleaning the sites so they can continue without the risks of hazardous materials.

The Project

Generally, a DEW site cleanup consists of four main structures. The land farms are large, usually rectangular berms over a key trench. Their fabric liner is filled with hydrocarbon-contaminated soil that is tilled and aired once a week or so until the hydrocarbons reach acceptable and harmless levels. We build this first and till it all during the first summer. By the end of the second summer the land farm is tested and graded so the tundra can come back.

These land farms are now like glorified landfills that vary in size from site to site. A land farm we worked on this past summer was 170 m x 90 m x 0.5 m deep (the depth is limited so that the soil can be tilled and aired).



The non-hazardous waste disposal facility is another rectangular berm filled with harmless garbage and covered with a couple of meters of fill to bring up the permafrost and freeze it forever. Permafrost has an active layer of .7 meters in the peak of summer that should seal all the toxins and other harmful materials in ice forever, global warming aside (there is a .8 meter global warming factor in place).

The USAF landfills are sealed in a geotechnical liner and get 2.6 meters of fill to bring up the permafrost.

The tier 2 contaminant disposal facility is quite a complicated berm within a berm. It has a fabric under a thick plastic liner and another fabric over top filled with soil that has been contaminated with PCBs and/or lead. This layer is covered with more liner and plastic welded shut. It is then covered with a final layer—three meters of fill—to bring up the permafrost.

All the facilities have several monitoring wells installed to keep track of the ground temperature. Many other items are built as well, garbage is collected, and the buildings are dismantled. PCB-painted sheets of plywood are containerized and shipped south by barge for incineration at the Swan Hill disposal site.

Details

I am the site surveyor. I work for GNG Surveys, LTD of Stony Plain, Alberta, Canada and have been surveying since 1980. When I am not on one of these sites (winter), I survey in the oil patch in Northern Alberta, Saskatchewan and British Columbia.

As for construction equipment, a typical site will have two smaller tack excavators, four cat 250 trucks (10-15 cu.m), three bulldozers (D3, D5 & D6), and a grader. The equipment is barged into a site at the beginning of a project and stays until the site is finished, usually in two seasons. Before we leave, all the fluids are drained and the equipment is blocked up so the tires don’t go flat over the cold winter.

Some projects take three to four years, some less. The project I am currently working is a two-year job. We generally start work here in the end of June, and that usually begins with snow removal from the facility locations. It usually ends the last week in September. It doesn’t take long for things to freeze here. The weather gets colder and things start freezing from the top, and because of the permafrost they also freeze from the permafrost up.

On the 5th of August last year, we awoke to blowing wet snow. It was quite cold for August. The job was winding down but I was still very busy putting the finishing touches on the USAF landfill.
A barge can only get in here for a small window in the fall, and the trip takes weeks. We can work only three months and only in the summer because of the weather. In fact, the weather forecast has snow for Friday, and that’s July the 27th.

The Surveying Requirements

The surveyor is responsible for all construction layout and volume computations. We start with the land farm so we can start tilling the contaminated soil. In between we start on the non-hazardous structure. Because of equipment and personnel, we can build only one structure at a time, so we move around as needed to get as much done as possible in our short stay. The surveying involves typical slope and grade-staking with colored flagging. There isn’t really a tolerance for elevation control, but final volumes need to be very close. The government sends out a surveyor each season for three to four days to audit and inspect the work.

We based one site on a local grid, and that was a disaster. Now we use NAD 83 and WGS 84. The initial site investigation puts in GPS control, from which we use conventional surveying. One meter rebar is used for the initial control. Later we bring a drill and set a 25 mm X 5 m iron pipe with a screw-on cap. The bottom two meters are cement grouted and the top three meters are sand filled. There are no markings on the cap, so we pile rocks around them to aid in locating them later.
 

Surveying Software

As you can imagine, because we’re out here in the middle of nowhere we need software that works and works well. Everything happens right here, on site, in real time. We don’t run back to the office to fix something or get something to work. So we use Traverse PC surveying software.
Layout and volumes, etc. are what it’s all about. I could not do this job with such ease without the help of Traverse PC. I can survey in the field first or survey on the computer first and reconstruct in the field. Layout and volumes are a snap. The volumes are extremely accurate and I never have to second guess whether the facilities are in the right place. Everything has to be electronically saved on CDs in DWG, ASCII, and Word DOC formats. I have had zero complaints thus far.

Local Help

We hire a certain number of local Inuit laborers per the contact. My helper is a young Inuit named Kamele who is very sharp and does a lot of the instrument work. Our job is to lay out the various facilities for clean up, because removal is not an option. As well, we do the volume surveys that are a large part of the funds of the project. Kamele doesn’t have formal surveying education but she is currently in school in Ottawa.

Living at the Arctic Circle

We have one project manager from Defense Construction Canada, a geotechnical engineer to do the testing, two people from Environmental Sciences Group to do the lab work on the soils to confirm when the toxins have been removed, a medic, a cook, a site superintendent, about 25 locals who work as laborers, heavy equipment operators, housekeepers, etc., and yours truly, the surveyor.

We travel to and from the site in a Twin Otter aircraft and sometimes in a slightly larger plane called a Dornier that brings our groceries. Flights here are never guaranteed because of the frequent thick fog, which is caused by ice that remains on the sea and in the bay.

We are required to have an actual camp, and we use typical construction trailers. The entire camp is barged in the fall before work starts on a site. If you count the local help, engineers, and people from down south you can have 35 to 40 people in camp. We have washing machines and dryers in the trailers so we can do laundry.

A nice day is 12 to 15 degrees celsius. It doesn’t usually freeze at night but both days and nights are often in the single digits. We never have short-sleeve weather; you always need something warm on. We’re not sure how the flowers can bloom or the birds can lay eggs and hatch young, but they do.

We are at a new site this year, an uninhabited island called Jenny Lind. There are many seals here so the fishing is very poor. The last site had trophy fishing every night, which made the whole job seem like a paid holiday.

This island has an overabundance of polar bears due to the overabundance of seals that are the favorite diet of the polar bear. We had four polar bears visit last fall in a matter of days, and now that the ice is breaking up we had one last night.

The northern lights are quite remarkable, but in the middle of summer we don’t see them. Because of the 24 hours of daylight, the sun is always high in the sky.
Bob Holtkamp works for GNG Surveys, LTD of Stony Plain, AB, Canada. He has been surveying since 1980.

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