2009-09-25_PERMIT FILE - M2009076 ‎(42)‎

• Permit No: M2009076
• IBM Index Class Name: PERMIT FILE
• Doc Date: 9/25/2009
• Doc Name: EPA Superfund Record of Decision
• From: Venture Resources
• To: DRMS
• Media Type: D
• Archive: No

CAPPING ALTERNATIVE
SURFACE CONTROL MEASURES WILL ELIMINATE CONTAMINATION OF SURFACE WATER DUE TO RUNOFF FROM THE
MINE TAILINGS AND WASTE ROCK SITES AND PREVENT HUMAN EXPOSURE THROUGH INHALATION AND INGESTION.
10CH MEASURES COULD INCLUDE REGRADING THE SITE TO STABILIZE EXISTING SLOPES AND CONTROL SURFACE
TER RUNOFF, PROVIDING A CONTAINING CAP OVER THE TAILINGS AND WASTE ROCK MATERIAL, OR
REVEGETATION OF THE SITE.
SIX TYPES OF CAPS WERE EVALUATED FOR EACH SITE INCLUDING SYNTHETIC LINERS, BITUMINOUS PAVEMENT,
SOIL CEMENT LAYERS, SOIL COVER, CLAY BARRIER/SOIL COVER, AND A MODIFIED RESOURCE CONSERVATION
AND RECOVERY ACT (RCRA) CAP - A FROST-RESISTANT CLAY BARRIER/SOIL COVER).
THE CAPPING ANALYSIS INDICATED THAT CONTAINMENT IS EFFECTIVE, TECHNICALLY FEASIBLE AND CAN BE
IMPLEMENTED. THEREFORE, THESE ALTERNATIVES WERE CONSIDERED FURTHER IN THE DETAILED SCREENING OF
REMEDIAL ACTION ALTERNATIVES. THE INITIAL SCREENING RESULTED IN THE FOLLOWING CAPPING
ALTERNATIVES FOR FURTHER EVALUATION:
NATIONAL TUNNEL
- SYNTHETIC LINER
- SOIL CEMENT COVER.
ARGO TUNNEL
- SYNTHETIC LINER
- SOIL CEMENT COVER.
GREGORY INCLINE
- REPLACEMENT OF EXISTING GABION WALL
• - SYNTHETIC LINER OR SOIL CEMENT COVER.
QUARTZ HILL TUNNEL
- PAVEMENT OF PARKING LOTS
- SYNTHETIC LINER OR SOIL CEMENT COVER.
BIG FIVE TUNNEL
- SOUTH SIDE OF CLEAR CREEK - REMOVE TO NORTH SIDE OF CREEK OR OFF-SITE DISPOSAL.
- NORTH SIDE OF CLEAR CREEK - SYNTHETIC LINER OR SOIL CEMENT COVER.
VARIOUS CAPS WERE ELIMINATED DURING THE INITIAL SCREENING. THOSE CAPS SCREENED OUT INCLUDED
SOIL COVER, CLAY BARRIER/SOIL COVER, BITUMINOUS COVER AND MODIFIED RCRA CAP. MOST OF THESE
COVERS COULD NOT BE IMPLEMENTED ON THE STEEP SLOPES. MORE DETAILS CONCERNING THE SCREENING
EVALUATION CAN BE FOUND IN SECTION 2 OF THE FEASIBILITY STUDY REPORT.
OFF-SITE DISPOSAL ALTERNATIVE
THE OFF-SITE DISPOSAL ALTERNATIVE CONSIDERS THE OPTION OF TRANSPORTING THE MINE TAILINGS AND
WASTE ROCK MATERIAL TO EITHER A LOCAL MUNICIPAL LANDFILL OR TO A RCRA PERMITTED LANDFILL.
THE MOST LIKELY MUNICIPAL LANDFILL WOULD BE A FACILITY OPERATED BY BROWNING FERRIS INCORPORATED
(BFI) NEAR 88TH AND TOWER ROAD NORTHEAST OF DENVER. THIS IS A RELATIVELY NEW FACILITY WHICH
REPLACES A BFI FACILITY ALONG COLORADO STATE HIGHWAY 93 BETWEEN GOLDEN AND BOULDER, WHICH HAS
NOW BEEN CLOSED. THE PRIMARY CONCERN WITH THIS ALTERNATIVE, HOWEVER, WOULD BE WHETHER OR NOT
THE APPROPRIATE REGULATORY AGENCIES OR THE OPERATOR WOULD ALLOW DISPOSAL OF MATERIALS FROM A
W CIA SITE AT A MUNICIPAL LANDFILL EVEN IF IT WAS NOT A RCRA CHARACTERISTIC WASTE. A SECOND
KERN WOULD BE THE IMPACT OF SUCH A LARGE VOLUME OF MATERIAL ON A LANDFILL DESIGNED PRIMARILY
FOR MUNICIPAL USE.
THE SECOND ALTERNATIVE FOR DISPOSAL OF THE MATERIAL IS LANDFILL AT A PERMITTED RCRA LANDFILL.
THREE SITES WERE INVESTIGATED, INCLUDING THE NEW LAST CHANCE SITE, OPERATED BY BFI NEAR LIMON,