OFR 97-492: Lewiston Quadrangle NURE HSSR Study

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National Geochemical Database—Reformatted Data from the National Uranium Resource Evaluation (NURE) Hydrogeochemical and Stream Sediment Reconnaissance (HSSR) Program

By Steven M. Smith
Version 1.40 (2006)

Brief History and Description of Data

[See History of NURE HSSR Program for a summary of the entire program.]

Maine
Subcontractors for the Savannah River Laboratory (SRL) collected at least 2,924 stream-sediment, 2,039 surface-water, and 1,938 ground-water samples from the southern half of Maine as part of the NURE Hydrogeochemical and Stream Sediment Reconnaissance (HSSR) program. Two different sampling protocols were used in Maine. Using the SRL Eastern protocol (SRL-E), 1,218 stream-sediment, 1,218 surface-water, and 636 ground-water samples were collected from Androscoggin, Cumberland, Franklin, Kennebec, Oxford, Somerset Counties in October and November of 1977. This area included portions of the Bangor, Bath, Lewiston, Millinocket, Portland, and Sherbrooke 1:250,000-scale quadrangles. Another 1,706 stream-sediment, 821 surface-water, and 1302 ground-water samples were collected by subcontractors using SRL Western protocols (SRL-W) between May and August of 1980 within the Bangor, Bath, and Eastport 1:250,000-scale quadrangles. These samples were sent to SRL for determinations of uranium and additional elements (16 in sediments and 9 in waters) by Neutron Activation Analysis. SRL was able to analyze 1,230 sediments and 3,977 waters from Maine. The analytical and site location data for all Maine samples were released in the New England Data Report [GJBX-107(82)]. Within the Maine portion of the Lewiston quadrangle, 619 stream-sediment, 619 surface-water, and 318 ground-water samples were collected by the SRL-E protocol. SRL was able to analyze 618 sediment and all water samples from the Lewiston quadrangle.

SRL sent the 1,218 SRL-E sediment samples from Maine to an unnamed contract laboratory for "Supplemental Analyses." Supplemental analytical determinations for up to 23 elements were reported for 1,214 of these samples in the New England Data Report [GJBX-107(82)]. The digital data file accompanying this report includes Supplemental Analyses for 619 sediment samples from Maine within the Lewiston quadrangle.

SRL also sent 1,643 SRL-W water samples from Maine to the Oak Ridge Gaseous Diffusion Plant (ORGDP) for analysis of 31 additional elements. Data for these additional analyses were also released as a digital data file accompanying the New England Data Report [GJBX-107(82)]. None of these samples were collected within the Lewiston quadrangle.

New Hampshire
Subcontractors for the Savannah River Laboratory (SRL) collected at least 1,699 stream-sediment, 1,694 surface-water, and 884 ground-water samples from New Hampshire as part of the NURE Hydrogeochemical and Stream Sediment Reconnaissance (HSSR) program. Samples were collected on a county-by-county basis from the entire state between July 1977 and January 1978. This area included portions of the Albany, Boston, Glens Falls, Lake Champlain, Lewiston, Portland, and Sherbrooke 1:250,000-scale quadrangles. The samples were sent to SRL for determinations of uranium and additional elements (16 in sediments and 9 in waters) by Neutron Activation Analysis. SRL was able to analyze 1,696 sediments and 2,576 waters from New Hampshire. The analytical and site location data for all New Hampshire samples were released in the New England Data Report [GJBX-107(82)]. A total of 429 stream-sediment, 429 surface-water, and 233 ground-water samples were collected within the New Hampshire portion of the Lewiston quadrangle. SRL was able to analyze all of the sediment and water samples from the Lewiston quadrangle.

SRL sent the 1,699 sediment samples from New Hampshire to an unnamed contract laboratory for "Supplemental Analyses." Supplemental analytical determinations for up to 23 elements were reported for 1,690 of these samples in the New England Data Report [GJBX-107(82)]. The digital data file accompanying this report includes Supplemental Analyses for 427 sediment samples from New Hampshire within the Lewiston quadrangle.

Vermont
Subcontractors for the Savannah River Laboratory (SRL) collected at least 1,677 stream-sediment, 1,663 surface-water, and 972 ground-water samples from Vermont as part of the NURE Hydrogeochemical and Stream Sediment Reconnaissance (HSSR) program. Samples were collected on a county-by-county basis from the entire state between August 1977 and March 1978. This area included portions of the Albany, Glens Falls, Lake Champlain, Lewiston, and Sherbrooke 1:250,000-scale quadrangles. The samples were sent to SRL for determinations of uranium and additional elements (16 in sediments and 9 in waters) by Neutron Activation Analysis. SRL was able to analyze 1,674 sediments and 2,633 waters from Vermont. The analytical and site location data for all Vermont samples were released in the New England Data Report [GJBX-107(82)]. A total of 156 stream-sediment, 156 surface-water, and 87 ground-water samples were collected within the Vermont portion of the Lewiston quadrangle. SRL was able to analyze 155 sediment and all water samples from the Lewiston quadrangle.

SRL sent 1,632 sediment samples from Vermont to an unnamed contract laboratory for "Supplemental Analyses." Supplemental analytical determinations for up to 23 elements were reported for 1,631 of these samples in the New England Data Report [GJBX-107(82)]. The digital data file accompanying this report includes Supplemental Analyses for 155 sediment samples from Vermont within the Lewiston quadrangle.

SRL: Lewiston Quadrangle
SRL also compiled the data from all Maine, New Hampshire, and Vermont samples collected within the Lewiston quadrangle. The SRL Neutron Activation Analysis data for 1,179 stream-sediment, 1,179 surface-water, and 638 ground-water samples were released in the Lewiston Quadrangle Data Report [GJBX-014(81)]. The Supplemental Analysis data were released in the Lewiston Quadrangle Supplemental Data Report [GJBX-348(81)].

Gold Analyses
Data for gold analyses of sediments by SRL neutron activation were released in the GJBX-135(82) summary report. The introduction of that report states:

"This report contains previously unreported neutron-activation analyses of gold in sediment samples determined at SRL. These data were not included in the standard SRL NURE data reports because the gold spectrum was not measured in the original analytical procedure and the report format was designed without the gold analyses being included. Gold analyses became available as the analytical procedure was refined, but the report format was not modified to incorporate these data."

Only those sediment samples that had detectable concentrations of gold by neutron activation analysis were given in the GJBX-135(82) report. Sediment samples with concentrations below detection limits were not reported and can only be ascertained by identifying which samples were actually analyzed by neutron activation at SRL.

Summary Tables
Because of the various laboratories and analytical methods used, some SRL samples may have been analyzed once, twice, or not at all. The following table summarizes the analysis of Lewiston quadrangle samples.

Combination of laboratories that analyzed samples for the Lewiston quadrangle.
Laboratory Analysis Sediments Waters
Only SRL 3 1,842
Both SRL and Supplemental Labs 1,199 0
Supplemental Lab only 2 0
Second SRL analysis 0 21
None 0 0
Total Samples 1,204 1,842
Total Data Records 1,225 1,842

The following is a list of all sample types collected and reported for NURE studies in the Lewiston quadrangle.

Summary of Lewiston quadrangle sample types.
Sediment Sample Type Number of Samples Water Sample Type Number of Samples
Wet Streams 1,204 Streams 1,204
    Wells 346
    Springs 292
Total Sediments 1,204 Total Waters 1,842

These Lewiston quadrangle samples were analyzed by one or more of the following methods:

Sediment Samples

Water Samples



Discussion of the Reformatting Process for Lewiston Quadrangle

Sediment Records
The Lewiston quadrangle sediment data consist primarily of stream-sediment records from the Lewiston Quadrangle GJBX-014(81) Data Report combined with Supplemental Analyses data from corresponding records in the Lewiston Quadrangle Supplemental GJBX-348(81) Data Report. Before combining these data, the SRL Neutron Activation data in the Lewiston Quadrangle GJBX-014(81) Data Report were compared with the equivalent records from the Maine, New Hampshire, and Vermont files in the New England GJBX-107(82) Data Report. In addition, the Lewiston Quadrangle version of the Supplemental Analyses data was compared with the Supplemental Analyses data found in the New England State files. The end result for most sediment samples is a single combined record per sample which includes all of the SRL Neutron Activation data plus all of the Supplemental Analyses data found in each of the Quadrangle and States digital data files. Occasionally these comparisons revealed major differences between corresponding records for some sediment samples. For these cases, an additional record per affected sample was kept to preserve all of the available data. The following problems were found and addressed during the comparison and reformatting stages for the Lewiston Quadrangle sediment data:

  1. For 21 sediment samples, the comparison process revealed major differences for analytical values reported for one or more elements determined by Neutron Activation. It could not be determined whether these alternate values represent a second analytical determination or a different interpretation of the data from the same Neutron Activation Analysis. For each of these samples, it was necessary to keep a second record containing the alternate analytical values. These records are identified by a comment in the REFORMAT field.
  2. The analytical values for many U, Dy, Lu, and V determinations differed slightly between the original Lewiston Quadrangle and New England State files. These variations are apparently due only to differences in rounding versus truncation of reported values or to differences in the number of recorded significant digits. Since the variation was insignificant, only one set of the values was retained for the affected elements.
  3. Neutron Activation data for 9 sediment samples found in the New England GJBX-107(82) Data Report, were missing in the corresponding records from the Lewiston Quadrangle GJBX-014(81) Data Report. The records from the New England States digital data files were kept for these samples.
  4. Occasionally, analytical values for Al, Ce, Eu, Fe, Hf, La, Lu, Sc, Sm, or Th were found in the New England GJBX-107(82) Data Report but were missing in the corresponding records from the Lewiston Quadrangle GJBX-014(81) Data Report. These values were added and that change was noted for each affected record in the REFORMAT comment field.
  5. Occasionally, analytical values for Dy, Eu, V, or Yb were found in the Lewiston Quadrangle GJBX-014(81) Data Report but were missing in the corresponding records from the New England GJBX-107(82) Data Report. These differences were noted for each affected record in the REFORMAT comment field.
  6. The date on which a sample was analyzed by Neutron Activation Analysis was only recorded in the State digital data files from the New England GJBX-107(82) Data Report. This information was added to each of combined sediment data records.
  7. Some of the site information reported in data records from the Lewiston Quadrangle Supplemental GJBX-348(81) Data Report were obviously erroneous. For example, all of the Lewiston stream-sediment samples were coded as stream-water samples collected in South Carolina. Since the Supplemental Analysis records commonly contain missing or erroneous site data, location and site description data from corresponding SRL Neutron Activation records were routinely used as the primary source when combining data for each sample.
  8. One stream-sediment sample was collected at a longitude of exactly 72°W, the dividing line between the Lake Champlain quadrangle and the Lewiston quadrangle. This sample was reported in the New Hampshire state file, the Lake Champlain quadrangle file and the Lewiston quadrangle file. The data record for this sample was assigned to the Lake Champlain quadrangle.
  9. An analysis of latitude-longitude site coordinates identified several stream-sediment samples that were missing coordinates, did not plot within expected state, county, or map boundaries, or had differing coordinates in corresponding records. To correct or confirm sample coordinates, the original field collection maps for Cumberland and Franklin Counties, Maine; and Orlean County, Vermont were obtained and re-digitized. The newly re-digitized coordinates were added to the database and the coordinates from the original file(s) were recorded in the COORDPRB comment field. When the newly re-digitized coordinates were not significantly different, that confirmation of the site location was also noted in the COORDPRB comment field.
  10. After re-digitizing, all 26 stream-sediment samples from Franklin County, Maine originally located in the Sherbrooke quadrangle now plot in the adjacent Lewiston quadrangle.
  11. Gold concentrations from the GJBX-135(82) report were added to the appropriate sediment records. A value of -0.01 (<0.01 ppm Au) was added to all other sediment samples determined to have been analyzed by SRL neutron activation. This value was chosen because 0.01 is the lowest reported gold concentration in the entire report.

Water Records
The Lewiston quadrangle water data consist primarily of ground-water and surface-water records from the Lewiston Quadrangle GJBX-014(81) Data Report. These records were compared with corresponding records from the Maine, New Hampshire, and Vermont portions of the New England GJBX-107(82) Data Report. The following problems were found and addressed during the comparison and reformatting stages for the Lewiston quadrangle water data:

  1. The sample type codes differed for 26 water samples. The New England GJBX-107(82) Data Report identified these samples as well waters (SAMPTYP 52) while the Lewiston Quadrangle GJBX-014(81) Data Report identified them as spring waters (SAMPTYP 53). Since the site description fields for these samples appeared to better fit a spring water site, the reformatted records are identified as spring waters. A comment in the REFORMAT field gives the alternate SAMPTYP value for each of these samples.
  2. The analytical values for many Al, Br, Dy, and Mn determinations differed slightly between the original Lewiston Quadrangle and New England State files. These variations are apparently due only to differences in rounding versus truncation of reported values or to differences in the number of recorded significant digits. Since the variation was insignificant, only one set of the values was retained for the affected elements.
  3. Occasionally, analytical values for Br or Mg were found in the New England GJBX-107(82) Data Report but were missing in the corresponding records from the Lewiston Quadrangle GJBX-014(81) Data Report. These values were added and that change was noted for each affected record in the REFORMAT comment field.
  4. One stream-water sample was collected at a longitude of exactly 72°W, the dividing line between the Lake Champlain quadrangle and the Lewiston quadrangle. This sample was reported in the New Hampshire state file, the Lake Champlain quadrangle file and the Lewiston quadrangle file. The data record for this sample was assigned to the Lake Champlain quadrangle.
  5. The original NURE format for surface-water files did not include much information about the character of the sample location. This missing information includes observations taken at each site on the stream width, depth, and flow, water color, surrounding vegetation, local relief, weather, and possible contaminants. This information is given in records for stream-sediment samples that were collected at the same locations. The available site descriptive information for stream-water sites were compared with the corresponding stream-sediment site records. The missing site descriptive data were then added to stream-water records from the corresponding stream-sediment sample records. Sources of data and any problems found are described in the REFORMAT comment field.
  6. An analysis of latitude-longitude site coordinates identified several stream-sediment samples that were missing coordinates, did not plot within expected state, county, or map boundaries, or had differing coordinates in corresponding records. To correct or confirm sample coordinates, the original field collection maps for Cumberland and Franklin Counties, Maine; and Orlean County, Vermont were obtained and re-digitized. The newly re-digitized coordinates were added to the database and the coordinates from the original file(s) were recorded in the COORDPRB comment field. When the newly re-digitized coordinates were not significantly different, that confirmation of the site location was also noted in the COORDPRB comment field.
  7. After re-digitizing, all 26 stream-water samples from Franklin County, Maine originally located in the Sherbrooke quadrangle now plot in the adjacent Lewiston quadrangle.


Download The Data

The NURE HSSR data are now available online in two databases: The sediment database (also includes data for soils and some rocks) at http://tin.er.usgs.gov/nure/sediment/ and the water database at http://tin.er.usgs.gov/nure/water/. From these two web sites, NURE HSSR data can be selected, examined, summarized, and downloaded by political boundaries (State and County), by quadrangle (1:250,000-scale, 1:100,000-scale, and 1:63,360-scale for Alaska or 1:24,000-scale for the Lower 48 States), and by hydrologic unit (drainage region, subregion, river basin, or sub-basin). Selected data can be downloaded as a dBase file, a shapefile, an HTML table, or ASCII text (tab- or comma-delimited).

Lewiston Quadrangle Sediment Data - 1,225 records
Lewiston Quadrangle Water Data - 1,842 records



Notes for Data Users

In the eastern United States, SRL collected samples primarily by county. Often, not all counties within a quadrangle were completely sampled. Although the Lewiston quadrangle was completely sampled, the laboratory and analytical methods used may vary by county such that adjacent counties often have very different analytical coverages.

There is a paragraph in the Quality Assurance section of the Lewiston Quadrangle GJBX-014(81) Data Report that describes the procedures SRL used to assure that NURE HSSR samples collected by subcontractors were located correctly. That paragraph reads:

"At least 8% of the sampled sites were routinely checked by SRL personnel or by a specified subcontractor to assure that the reported field locations were accurate. Based on these quality assurance checks, more than 98% of the sampled sites were judged to be located as accurately as they could be plotted on county road maps. No evidence has been discovered of deliberate malfeasance by the sampling teams. Most sites that were mapped incorrectly were within 300 meters of their correct locations. Thus, the goals of a regional reconnaissance have not been compromised by mapping errors."

When assigning FIPS codes (State and County designators) to each sample and comparing these values to the State and County designations in the SRLID field, it was discovered that several samples from Cumberland County, Maine plotted in the adjacent Oxford County. All of these samples are in Otisfield township. A little research revealed that Otisfield township officially seceded from Cumberland County on July 4, 1978. When the NURE samples were collected in October and November of 1977, Otisfield township was still part of Cumberland County, Maine and the samples were correctly labeled "MECU" in the SRLID field. Today, these MECU sample sites are now in Oxford County.



Other NURE Geochemical Data for the Lewiston Quadrangle

None found.



Lewiston Quadrangle NURE Bibliography



Links Within Open-File Report 97-492

Back to Maine NURE data
Back to New Hampshire NURE data
Back to Vermont NURE data
Frequently Asked Questions Concerning NURE HSSR Data
Home Page: USGS National Geochemical Database - NURE HSSR data



Page written by Steven M. Smith (smsmith@usgs.gov)
Version 1.20: August 07, 2000
Version 1.30: September 11, 2001
Version 1.41: February 23, 2006

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