D E C banner
D E C banner


The New York State Department of Environmental Conservation has added a link to a translation service developed by Microsoft Inc., entitled Bing Translator, as a convenience to visitors to the DEC website who speak languages other than English.

Additional information can be found at DEC's Language Assistance Page.

Shop-Built Mercury Sampler

Close-up view of shop-built mercury sampler
Shop-Built Mercury Sampler

Sampling mercury presents problems because the water quality standards are very low and because there are many potential sources of sample contamination. Section 6.4.2 of EPA Method 1669 Figure 2 (link to method/figure can be found under Off-Site Links) discusses an approach that we have found to be very satisfactory and easy for field personnel to operate. The essential elements are a plastic cage that holds a lab-cleaned sample bottle and a mechanism to open and close the lid of the bottle while it is underwater. We have found that simply opening and closing a bottle in the air where dust and vapors are present can affect the amount of mercury in the bottle.

Lowering the shop-built mercury sampler into a tank at a wasatewater treatment plant
Mercury Sampling at Wastewater Treatment Plant

This shop-built ultra-high density polyethylene system is easy to build and easy to operate. Neither glue nor welding nor metal fasteners are used. The cage is made from three ¾ inch flat-stock discs held together with 5/8 inch diameter dowels. The dowels and discs are friction fitted and pegged with 3/16 inch diameter dowels. Short 3/8 inch diameter pegs with added lengths of Masterflex™ tubing (for greater friction) secure the bottle at the base of the cage. A nylon screw fitted into a threaded hole through the center plate locks the bottle in place. The top disc of the cage is threaded for six bolts. A flange with holes matching those in the top disc is attached to the bottom of a 2 inch diameter long tube by means of small diameter dowels driven in from the inside of the bore. The top of the cage is fastened to the flange with six nylon bolts. If the dowels should loosen the long rod in the bore would prevent them from coming all the way out. The long rod (1 ¼ inch diameter) goes through the bore of the long tube. The bottom end of the long rod can be drilled out to accommodate the knurled top of a VOC container or it can accommodate a circular plate holding short pegs that engage the top of a wider diameter lid, as shown in the photo. Pegs through the long rod limit its travel through the tube. A threaded hole near the top of the long tube takes a short nylon bolt that secures a strap the operator can hold.

Wastewater treatement plant operator releasing the cap to seal a sample using the mercury sampler
Submersing Sampler and Opening Sampling Vial

The operator lowers the loaded cage into water, swirls it to dislodge extraneous particles, twists the long rod to open the bottle, and twists to close it.

This design requires sampling bottles of uniform size and geometry.

This Fact Sheet is also available as a PDF file (697 KB).

  • Important Links
  • Links Leaving DEC's Website
  • PDF Help
  • For help with PDFs on this page, please call 518-402-8179.
  • Contact for this Page
  • Division of Water
    625 Broadway
    Albany, NY
    Send us an email
  • This Page Covers
  • Page applies to all NYS regions