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through the end of 2014. Available data for the all three cuffendy monitored creeks, Newlin Creek, Magpie
<br />Creek, and Second Alkali Creek are included on the table. There are a total of five monitoring points.
<br />A review of the data shown on the table indicates that only one (Magpie Creek- upper) of the five current
<br />monitoring points was approved at the beginning of 1985. The table shows "not approved" where a
<br />monitoring location was not yet part of the monitoring program.
<br />Newlin Creek data for the upper and lower monitoring points include the period 1997 -2014. These two
<br />locations were approved in 1997. From 1979 through 1996, flow events were monitored at only a
<br />single point (eliminated by revision) located approx midway between the two current locations. Magpie
<br />Creek data include the period 1991 -2014. The lower monitoring point (MC2) was approved in 1997.
<br />No flow events were documented prior to 1985 at the upper (MCI) location, so the data table begins at
<br />this date. Second Alkali Creek data include the period 1991 -2014 for the single monitoring point. This
<br />location was approved for monitoring in 1991.
<br />3. Identification of uossible long -tern trends in surface water flo
<br />The streamflow table provided in response to Item #2, above, includes all available monitored flow rate
<br />data for Newlin Creek, Magpie Creek, and Second Alkali Creek. Included with this submittal are
<br />graphs of these data shown as measured flow rate against time. These graphs have been developed for
<br />the purpose of evaluating any apparent long -term trends in surface water flow.
<br />These flow data are measurements of flow that represent a rate of flow at one moment in time. Due to
<br />the ephemeral nature of all three creeks, flows are typically of very short duration. Almost all flow
<br />events were observed to persist for less than a day. Only Newlin Creek flows could, during some years,
<br />continue for up to several weeks during the spring runoff. Importantly, measurement of total flow
<br />quantity is not required and no such data exists for flows in Southfield permit area
<br />The intermittent flows in the monitored creeks are a direct result of the the number of significant rain
<br />events in the Southfield area In the case of Newlin Creek, observations on the creek over time suggest
<br />that the number flow events are more dependent on snow melt runoff, typically in the second calendar
<br />quarter, than on rain events.
<br />The Southfield PAP and the Division concur that the quantity of surface and subsurface flows in the
<br />three creeks have not been impacted by Southfield's mining operations. In the long term, flow in the
<br />creeks will depend on the number of significant storm events in the area and, to some extent, on
<br />snowpack levels in the higher elevations. We believe that long -term trends in flow quantity therefore
<br />can not be predicted by past flow rate measurements but are dependent only on firture precipitation
<br />trends in the Southfield area.
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<br />Newlin Creek, Magpie Creek, and Second Alkali Creek are currently monitored as discussed in Item
<br />#2, above. The approved list of chemical parameters for analysis includes pH (field), Conductivity
<br />(field), Temperature (field), Solids, total dissolved (TDS), Solids, total suspended (TSS), Oil and grease
<br />(visual), Sodium absorption ratio, Bicarbonate as HCO3, Calcium, total, Chloride, Njagnesium, total,
<br />Nitrogen - nitrate nitrite, Selenium, total, Phosphate, as P, Sodium, total, Sulfate, Iron, total, and
<br />Manganese, total.
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