excursions

Mid-Conference Excursions – 5th September 2018

Excursion 1 – The Miracle of Bad Schlema – A heavily devastated uranium mining site is now again a spa

Guidance:                    Dr. Peter Schmidt (Wismut GmbH)

Date:                            September 5, 2018, 8:00 am – 6:00 pm

Short description:

Before world war two, Bad Schlema was an internationally well reputed spa site where every year thousands of patients and recreation seekers were treated by use of radon containing water. After the war, from 1949 to 1990, Schlema became the hub of intensive uranium ore mining. More than 80’000 tons of uranium were brought to surface. Waste rock material with a volume of 47 Million m³ was dumped up in altogether 47 piles, often erected close to residential areas. This all caused serious impacts on the environment and public health, and a dramatic devastation of the landscape (Fig. 1).

          Figure 1: Waste rock pile #H250 in mid of Schlema and reclaimed site after pile relocation

In-situ remediation of waste rock dumps, stabilisation of near surface galleries, controlled flooding of the mine and treatment of contaminated mine and seepage water were the central remediation activities at the site. Today, only a few legacies are still requiring remediation. Long-term tasks as environmental monitoring, water treatment and management of radioactive water treatment residues are the dominating post-remedial activities. In 2005, the site regained its former name Bad Schlema, with it the rebirth of the spa became officially recognised through the Saxony government. A modern spa complex is now in operation, where again radon containing water helps to cure diseases. And to top it, at the surface of the covered radioactive waste pile #H38neu golfers can follow their hoppy (Fig. 2).

Figure 2: Remediated waste rock pile ‘H38neu (on top: Mine ventilation shaft, golf course)

The field trip will draw attention to still ongoing remediation as well as to long-term surveillance activities. A visit of the water treatment plant is planned. Further, the immobilization of water treatment residues and their disposal at a technical disposal facility on waste pile #H371 will be demonstrated (Fig. 3). At this pile the trip participants can also study the standard cover construction at the Schlema radioactive waste dumps. In the afternoon, a travel through the remediated waste rock pile landscape with explanations to the long-term monitoring system at the Schlema site will end the trip.  

Figure 3: Water treatment facility in Schlema-Alberoda, disposal site for treatment residues at H#371

Number of seats limited to 48.

Excursion 2 – The Wismut Uranium Tailings Remediation Project – Progress achieved with respect to diversifying legal requirements

Guidance:                    Ulf Barnekow (Wismut GmbH)

Date:                            September 5, 2018, 8:00 am – 6:00 pm

Short description:

In Eastern Germany uranium mining lasted from 1945 until 1990 leaving enormous environmental impacts. The former Soviet-German WISMUT company produced a total of about 216,000 t of uranium, mainly in two large mills located near Seelingstädt (Thuringia) and Crossen (Saxony). Nearby these former milling sites, Uranium mill tailings from soda-alkaline and from acid leaching processing schemes were discharged into tailings ponds erected in mined-out open pits or in ancient gravel quarries and valleys.

The four tailings management facilities (TMF) Culmitzsch (Fig. 1) and Trünzig near Seelingstädt and Helmsdorf and Dänkritz 1 near Crossen (Fig. 2) cover a total area of about 580 ha and contain more than 160 million m3 of uranium mill tailings. Since 1991 these tailings objects are under remediation.

Figure  1: Aerial view of Culmitzsch TMF (view from SE to NW), Oct. 2017

Figure  2: Aerial view of Helmsdorf/Dänkritz 1 TMF including replacement waters for avifauna (view from S to N, Oct. 2017)

Dry in-situ decommissioning is the preferred remediation option for all of Wismut´s tailings ponds. The field trip will familiarize the participants with the remediation approach, the main remediation steps and the progress achieved to date. During the field trip we will visit all of Wismut´s large tailings ponds. The trip will present more or less the follow-up of the main remediation steps including for example the installation of a water collection and water treatment system, interim covering of tailings beaches, dam reshaping, re-contouring of pond areas, final covering, and revegetation of the tailings sites.

The field trip will draw particular attention to the challenges of remediation regarding geotechnical stability, water treatment and management as well as nature conservation restrictions. The latter aspect will be illustrated on the basis of the planned tailings remediation object Dänkritz 2 and its created replacement waters for birds (Fig. 3).

Figure  3: Dänkritz 2 tailings pond to be remediated: Biotope and breeding habitat of strongly protected birds [left], Helmsdorf replacement waters for avifauna [right] (Sept./Oct. 2017)

Number of seats limited to 48.

Excursion 3 – Lignite Mining Boat and Bus Tour:

The conference participants take a boat trip on a quarry lake. A bus will take you from the conference venue to the lake markkleeberg, starts at 9.00 am. There, the various and special tasks of lignite mining remediation are explained by LMBV mbH on a guided boat tour. Afterwards, the bus will take you to further mineclosure sites of abandoned and active lignite mining. MIBRAG mbH allows site visits to their reclamation and remidiation work.

Mine Schleenhain

Markkleeberg Lake