EPA Method 5035

In and effort to improve the quality of results for Volatile Organic Compounds (VOCs) in soil, the EPA has published method 5035. This method describes sampling and preservation steps required for the collection of soil samples for 8015B, 8021B and 8260B VOC analyses. It represents a very significant change in the sampling procedure in the field and at the lab to ensure that analyte losses are minimized.

Research has shown that data obtained from "hand-packed" soil jars may show low bias caused by three processes:

• In the course of packing a jar and again while sub-sampling at the laboratory, agitation and aeration of the soil material provides the opportunity for volatilization of the VOCs. (This effect is exacerbated when the ambient temperature is high when sampling)

• Try as we may, getting a clean airtight seal on the soil containers is difficult. Some diffusion out of the sample container is possible during shipping and in storage prior to analysis.

• Without a preservative, and after the aeration in the jar packing process, the soil sample can begin to "bioremediate" itself. This is of particular concern with petroleum related contaminants.

Method 5035 attempts to minimize these losses. Hand packing of jars is replaced with dispersion of 5 grams of soil into 5 mL of either methanol or a sodium bisulfate solution (NaHSO₄). The choice of preservative is a function of soil type, expected concentration range and regulatory requirements. The methanol preservation procedure is the same as what is used for the Massachusetts VPH analysis.

A disposable plastic syringe with the end of the barrel removed is used in place of a shovel to take a measured, representative coring of the soil material. The core is expelled from the syringe into the preservative filled VOC soil vial. This technique minimizes soil agitation and facilitates transfer into the sample container without risk of "dirtying" the jars threads or septum seal.

These changes unfortunately mean a more elaborate sampling procedure and more containers to keep track of in the field (and back at the lab). Use of hand packed jars will be the exceptions.

EAI is prepared to provide you with the expertise and equipment to help you transition to the new protocol:

• The methanol prep should be sufficient to meet most regulatory needs, Mass VPH is an example. The sodium bisulfate preservation will be needed when MCLs require lower reporting limits. Call to discuss project specific reporting limit needs.

• We’ll provide you with the necessary equipment: sampling syringes, pre-preserved vials and some instructions.

• Our field crew is available to help.

There are other options to encapsulate and temporarily preserve soil samples such as the EnCore™ sampling system. We are able to accept samples collected using this apparatus. We feel that due to limitations of the EnCore™ system that the approach outlined above is a better alternative.

We will continue to accept hand packed jars… at some point we’ll need to flag such data as "not field preserved".

EAI will provide you with any training and the sampling equipment necessary to be compliant with method 5035 for VOC sampling. We’d love to hear your feedback of how these changes effect your field sampling efforts. Please give us a call if you’d like to discuss this hot topic

Summary of Options for Method 5035 from SW-846

EPA Method 5035: Soil Sampling Procedure

Eastern Analytical, Inc. (EAI) provides the following sampling supplies and instructions in order to comply with the sampling procedures outlined in SW-846, Update III. These sampling procedures apply to soil samples being analyzed by the following analytical methods: 8015B, 8021B, and 8260B. It is recommended that EAI customers read this procedure carefully and consider your project needs to insure that the regulatory requirements are met.

Sample Collection Materials Provided by EAI, per sample location:

1. 5mL polypropyl syringe, sample collection and % solids container.
2. 40mL pre-cleaned, pre-weighed, Sodium Bisulfate preserved glass containers (collect in duplicate)

(Note: if you are analyzing the sample only for method 8015, the Sodium Bisulfate containers are not provided as they are not necessary.)

     3.   20mL pre-cleaned, pre-weighed, Methanol preserved glass container

If Trip Blanks are required for your project, the following is provided:

1. 20mL pre-cleaned, pre-weighed, Methanol preserved glass container

Instructions

1. If at all possible, at least 7 days PRIOR TO THE SAMPLING EVENT, please call EAI to arrange preparation, packaging and delivery of the necessary containers and syringes. In addition to the standard information you provide for your bottle orders (date needed, project ID, number of sampling locations, date or return, etc.) please tell EAI what VOC method you are using, the expected concentration ranges expected with the required reporting limits, and if you need trip blanks.

2. EAI will prepare and ship the appropriate number of sample containers AND syringes for the project. If Trip Blanks are required, this will include at a minimum one(1)sodium bisulfate and one (1) methanol trip blank per batch.

3. It is recommended that the sample containers be labeled prior to collecting the sample. Field personnel are to prepare the sample site in accordance with best sampling practice and immediately withdraw the syringe barrel to the 5mL mark and plunge the syringe into the soil to the depth of the pre-set sample capacity.

4. Make sure the correct sample identification is on the container, open the vial and insert the syringe barrel into the vial. Expel the soil plug into the Methanol without splashing and then again two more times into the Sodium Bisulfate vials if low level detection limits are needed.

5. Completely agitate the sample in the vials to produce a slurry.

6. Collect a sample from the same sampling point, with the same syringe, retain the sample in the syringe using the end cap to secure.  This will be used for dry weight determination.

7. Initiate a Chain-of-Custody record for all samples collected.

8. Chill the samples to 4 degrees C. and transport the sample(s) to the laboratory as soon as possible. The maximum holding time from date of collection is 14 days.

Note: This sampling procedure and pre-preserved containers provided by EAI will allow your projects the ability to have your samples analyzed at the low level concentrations (<200 ug/kg) and the medium level concentrations (>200 ug/kg). If your project requirements and site history are known at the time of project planning, you may request EAI to provide only one of these options: low level or medium level.

What will EAI provide in their soil sampling kit to insure that my project is compliant with Method 5035 ?

FINAL POLICY PRESERVATION OF VOCs in SOIL SAMPLES for NEW HAMPSHIRE MARCH 2000: http://www.des.state.nh.us/orcb/doclist/voc.pdf is 96,329 bytes in size & was updated at 3/20/00 2:55:40 PM GMT.