Drill mud additives serve a variety of purposes during drilling and are adjusted or used as a situation arises. Our concern isn't so much how a drill mud additive is used as to what it contains; certain types of additives, such as biocides, tend to use toxic chemicals. [This was originally written in 2009. More information has since become available.]
Aldacide G is a biocide made by Halliburton and its Material Safety Data Sheet (MSDS) can be viewed or downloaded. All of Halliburton's drill mud additives' MSDSs, in addition to other information about additives, can be seen at their site (choose Fluid Services).
Material Safety Data Sheets are used by companies and their workers so that they can handle chemicals and compounds safely. Chemicals of concern are indicated along with a percentage or amount in the product. Hazards are listed along with recommended safety devices or gear needed for handling (gloves, goggles, etc.). Drill mud additive MDSDs that we've seen generally offer very little information. Companies are not required to provide information about "proprietary" substances in the product.
Aldacide G has one chemical listed on its MSDS -- glutaraldehyde. Is this chemical dangerous? The MSDS gives some indications but generally a person must look elsewhere for the answer.
The Endocrine Disruption Exchange
The Endocrine Disruption Exchange (TEDX) has examined a large number of MSDSs for drill mud additives and some fracturing products and has organized data by their use in individual wells (Washington's McBride 28-13 and Wyoming's Crosby 25-3) or in states (Colorado, Montana and New Mexico). Their analysis shows broadly the health effects according to chemicals and for specific additives. More useful are their Excel spreadsheets where they pack a lot of information about each chemical or additive according to its characteristics and known and suspected health effects including causing cancer.
To find the spreadsheets and analyses at The Endocrine Disruption Exchange's website, select Chemicals and Natural Gas.
Petroleum Services Association of Canada
The Petroleum Services Association of Canada has their own drill mud additive list which shows toxicity. In Canada, drill waste must be tested for biologic toxicity unless the driller tailors their additives and quantities so there will be no toxicity. We would like to see something like this done in this state.
A confusing aspect of the PSAC list is that values of 75% or more are considered non-toxic (in the Initial EC50(15%) column). So the lower the value, then the more acutely toxic. Some additives like Aldacide G have a specific value. Use above this quantity automatically requires a toxicity test of the waste.
Crosby 25-3 Well in Wyoming
A well where Aldacide G was used and for which a large amount of information is available is the Crosby 25-3 well in Wyoming where there was a blowout causing extensive ground surface and aquifer contamination. The operator has a public website with documents, and MSDSs for the drill mud additives used, related to the environmental remediation.
Generally, the additives that caused most concern were those that contained petroleum products (kerosene) and the biocide Aldacide G. Unfortunately there isn't a way to test for glutaraldehyde, not the same way that hydrocarbons like kerosene can be tested for in universally accepted methods.
One remediation report for the Crosby well does publish quantities of additives used; the first we've seen of this. In the Crosby well Terracon estimates that the concentration of glutaraldehyde -- 350 gallons were used -- "ranged from approximately 93 ppm up to 270 ppm."
There are more environmentally friendly alternatives to many of the really toxic additives and industry needs to be encouraged to use them.
The Endocrine Disruption Exchange website
We've found their Crosby 25-3 and Colorado Excel spreadsheets the most useful. Note that the Wyoming well used products not on the Colorado spreadsheet. No list is exhaustive. The website has a useful list of definitions of the different types of mud additives and some of the materials used in fracturing.
Windsor Energy Crosby 25-3 website
The Crosby 25-3 mudlist with links to MSDSs
Remedial Investigation Work Plan -- Final in Appendix B lists the drill mud additives used, their chemicals and quantities. Highlighted additives/chemicals were those of concern.
What Happened at Fernow
Fernow Experimental Forest
Discharge Monitoring Report
Liming the Pit
A Short History of Fracturing
What Happened at Fernow
Recommendations & Sources
Gas Well Study is the examination of natural gas wells in West Virginia.
Underground Injection Control Class 2 Wells
These wells are used either for the disposal of oil and gas liquid waste or for the enhanced recovery of oil or natural gas.
Gas Well Study Site Visits
Annual reports, environmental assessments, and individual well information.
Select videos from the Gas Well Study YouTube channel.
What Happened at Fernow
An investigation into what caused the vegetation death in the land application area after landspraying hydraulic fracture flowback waste.
The Spill at Buckeye Creek
An investigation into a spill from a Marcellus well site into Buckeye Creek in Doddridge county.