Dames & Moore, 1999 - USDA Forest Service

of water exiting from the portal. Samples were submitted for total recoverable and dissolved metals
analyses and conventional parameters. Field measurements (pH, specific conductivity, temperature.
oxidation/reduction potential, and ferrous iron) were collected and recorded in the field.
The data at P-1 were compared to WQC and for those metals where WQC is not available, to surface water
background and MTCA Method B cleanup levels for surface water. Additionally, as the water exiting the
portal is indicative of groundwater from the bedrock aquifer, the data were compared to the Washington
State groundwater criteria as provided in WAC 173-200 and under MTCA Method B cleanup levels for
groundwater. The following PCOCs were identified at P- 1.
b
Regulatory
Guidance
Surface Water
Criteria
Groundwater
Criteria
May 1997
Cd, Cy Pb, Zn, pH
As. Be, Cd, Cu, Pb, Zn,
Sod, pH
May 1998
Cd. Cu, Pb. Zn, pH
Cd, Cu. Fe. Pb, Zn,
Sod, TDS, pH
Dissolved aluminum, barium, thallium, and uranium concentrations are above surface water background
in May. Aluminum and barium continue to exceed background concentrations in July. Manganese is
above background from May to September. Concentrations were not above available MTCA Method B
levels. Cadmium, copper, and zinc consistently are above surface water WQC in May. Lead is above
WQC in May and July.
The PCOCs identified based on groundwater criteria are similar to those identified for surface water.
Cadmium, copper, and zinc are above criteria in May and July. Arsenic and beryllium indicate a single
exceedance in May 1997. Sulfate is consistently above criteria from May through September. Cadmium
is the only metal that is above criteria in September.
Concentrations of dissolved aluminum, cadmium, copper, iron, lead, manganese, and zinc decreased from
May to September 1997. Dissolved cation concentrations (calcium, potassium and sodium) increased
during the same timeframe. Field measurements indicated that pH values changed from acidic (4.8 SU)
in May to neutral (7.0 SU) in September.
Increased concentrations of dissolved aluminum, cadmium, copper, iron, manganese, and zinc were
detected in the sample collected in May 1998 as compared to May 1997 data. The increased
concentrations are likely related to the timing of the sampling event and position on the hydrograph.
Stream flow measurements were similar for each of the sampling events in 1997 and 1998 with flows of
2.63 cfs in 1997 and 2.54 cfs in 1998.
5.3.4.2 Confluence with Railroad Creek (P-5)
July 1997
Cd, Cy Pb, Zn, pH
Cd. Cu, Pb, Zn, SO4,
PH
Grab samples were collected from the 1500-level main portal drainage prior to the confluence with Railroad
Creek at location P-5 during MayIJune, July, and September 1997 and in May 1998 to evaluate source
loading and transport to Railroad Creek. Samples were also collected weekly from May 18, 1997 to June
16, 1997. The samples were submitted for the same suite of analyses as the portal opening (P-I). Field
measurements were also collected. The data,is summarized in Table 5.3-30.
\\DM-SEAI\VOLI\COMMOMWP\WDATAWO5\REPORTSWOLDEN-NUU-O-Od~ 5-32
17693-005-0 19Vuly 28.1999; 1 1 :09 AMDRAFT FINAL R1 REPORT
September 1997
Cd, Cu, Zn
Cd, SO4, TDS